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Digestate liquid fraction derived from four biogas plants fed with different organic sources (animal manure, mixed waste, agricultural waste and urban sewage sludge) was treated using a series of processes that were integrated on a mobile platform. These processes included microfiltration and ultrafiltration for the removal of solids and large organic molecules, selective electrodialysis for the recovery of nutrients, UV ozonation to selectively oxidize pharmaceuticals and reverse osmosis for clean water production. Results showed that 48–58% of the digestate could be recovered as water that can be used for irrigation or process needs, while 51–67.8% of nitrogen could be recovered by the selective electrodialysis process and used for fertilizer production tailored to farmers' soil and crop requirements, aiming to replace fertilizers from non-renewable minerals. Applying UV ozonation for the oxidation of pharmaceuticals before the nutrient recovery step was found to be twice as effective as applying it after nutrient recovery. The solid fractions of various digestates were applied as fertilizers for lettuce grown in pots, with the digestate from agricultural and food waste origins giving some of the best yields with the lowest GHG emissions. The solid fraction from sewage sludge digestate produced the highest yields in lettuce growing, but also resulted in much higher GHG emissions than the other fertilizers. A business model for the implementation of the developed technology in three operational scenarios concluded that a mobile solution shared between small anaerobic digestion plants in a region could have a five-year return on investment of 41.6% and a payback period of 1.96 years. • Mobile process for digestate refining and volume reduction. • NOMAD technology reclaimed up to 58% of water from digestate. • Achieved over 90% antibiotic removal within 2 h using UVOX technology. • Produced fertilizers were at least as effective as commercial organic ones. • Five-year 41.6% return on investment and 1.96 payback period calculated. [ABSTRACT FROM AUTHOR]

The carboxylic platform via mixed culture anaerobic fermentation holds significant potential for biorefinery applications. However, effective and economical methanogenesis inhibition remains crucial for maximizing production efficiency. This study investigates the use of biomass tar, derived from the pyrolysis of rice husk, as a methanogenesis inhibitor to enhance the anaerobic fermentation of food waste and boost the production of reduced fatty acids. The experimental results demonstrated that adding 5.0 g/L of tar achieved the highest hydrogen production, reaching 65.0 mL/g VS. Furthermore, increasing tar concentrations led to higher yields of reduced and longer-chain fatty acids, with butyrate production peaking at 726.8 mg COD (chemical oxygen demand)/g VS (volatile solid) with 30.0 g/L tar, and caproate at 128.6 mg COD/g VS with 10.0 g/L tar. GC-MS analysis identified phenolic compounds and furan derivatives as the primary inhibitory agents, which gradually degraded during fermentation. Microbial community analysis revealed that the tar-based inhibitors effectively suppressed dominant methanogenic archaea, including Methanothrix , Methanobacterium , and Methanosarcina , while promoting the enrichment of chain-elongating bacteria such as Clostridium_sensu_stricto and Clostridium_IV. This study suggests that integrating biomass tar from pyrolysis with anaerobic fermentation can serve as a highly efficient biorefinery approach, fully utilizing diverse organic wastes for sustainable energy production. [Display omitted] • Biomass tar (5.0 g/L) inhibited methanogenesis, boosting hydrogen production to 65.0 mL/g VS. • Tar supplemented in the range of 5.0 g/L to 10 g/L enhanced the production of hydrogen and VFAs. • Phenolic compounds and furan derivatives were key inhibitors, enhancing carboxylic acid production. • Tar addition enriched Clostridium species and suppressed methanogenic archaea like Methanothrix and Methanosarcina. [ABSTRACT FROM AUTHOR]

The successful upscaling of anaerobic fermentation (AF) still relies on ensuring the stable production of volatile fatty acids (VFAs) in high concentrations and yields. The unforeseen events taking place at industrial scale can compromise the AF stability, thereby decreasing the cost-effectiveness of the process. To assess process stability against disturbances and identify AF failure indicators, this investigation explored the effect of starvation and pH control failure in a continuous reactor. The starvation disturbance did not affect AF performance and methanogenesis was not restored, confirming the relevance of selecting proper conditions (25 °C and pH 6.5) to ensure methanogenesis suppression. By contrast, the uncontrolled pH provoked a pH drop to 4.5, limiting the acidogenesis metabolisms and modifying the metabolites profile due to microbiome reshape. Lactobacillus , and members of Lactobacillaceae, Lactobacillales, and Bifidobacteriaceae dominated the microbiome in the pH disturbance, revealing lactic, succinic and oxalic acids as warning indicators of the acidogenesis failure. Nevertheless, the AF was completely recovered after the disturbances evidencing the microbiome robustness against pH range between 4.5 and 5. • 25 °C and pH 6.5 suppressed methanogenic activity at long hydraulic retention time. • Starvation period shorter than hydraulic retention time did not alter process yield. • pH drop limited acidogenesis while hydrolysis remained highly efficient. • Lactic, succinic and oxalic acids indicated the level of process damage. • Metabolic plasticity enabled microbiota recovery after disturbances. [ABSTRACT FROM AUTHOR]

Radical-induced polymerization in persulfate (PS)-based advanced oxidation process (AOP) is attracting attention in water decontamination. Herein, we revealed its new role in rapid recycling of perishable food wastes using KOH activated PS. A glucose (Glu) solution of 250 g C/L was applied to mimic the carbohydrate-rich raw material with 50–60% moisture in conventional composting, wherein boosted humification occurred after addition of solid KOH/PS. Intense heat release (from 25 to 79.4 °C), mainly generated from KOH dissolving and exothermic radical chain polymerization, was observed within 2 min. Solid KOH addition contributed to synergistic PS activation by base and self-heating, realizing complete PS decomposition and fulvic like acid (FLA, 210.8 g C/L) formation within 10 min. Extracted FLA promoted cucumber seed germination and fresh weight of chickweeds by 40.0% and 128.3%, respectively. Identified •OH and SO 4 •- played primary roles in FLA formation through aromatization, carboxylation, and polymerization, wherein several key reactive intermediates such as 5-hydroxymethylfurfural and aromatic radicals (i.e. 1,2,4-benzenetriol radical) were formed. Moreover, the humification process simultaneously produced K 2 SO 4 (i.e. the end product of PS decomposition) which could be used as a typical K/S fertilizer. Scaling-up humification of waste cooked rice and fertilization results further supported the potential of solid KOH/PS in efficiently converting food wastes into FLA and K+-rich compound fertilizer. • Persulfate/KOH realized glucose's fast humification by radical-induced polymerization. • Temperature rose from 25 to 79 °C in 2 min due to KOH dissolving and polymerization. • Base and self-heating synergistically activated persulfate (PS). • Product containing fulvic-like acid and K+ could be used as a compound fertilizer. • Waste cooked rice as a model food waste verified KOH/PS-induced humification. [ABSTRACT FROM AUTHOR]

This study explores a novel integration of electro-physicochemical technologies to generate energy and treat water from combined food waste (FW) and blackwater (FW-BW), with BW containing waste activated sludge with simulated flush water. The FW-BW substrate was gravity-separated and pretreated with hydrodynamic cavitation (HDC). Solids from gravity separation were used for energy generation via anaerobic digestion (AD) alone or integrated with microbial electrolysis cells (AD-MEC). HDC pretreatment had 51.6% more CH 4 production in 5 days (266 mL CH 4 /g VS) and 63% more in 30 days compared to AD without HDC. The CH 4 production after 5 days of digestion with HDC pretreatment (266 mL CH 4 /g VS) was similar to the amount produced without HDC over 30 days (263 mL CH 4 /g VS). Using MEC increased CH 4 production by 12.7% compared to AD-only. The liquids from gravity separation were treated with electrocoagulation (EC) at 15 V (90 min), which removed 96.2% of the chemical oxygen demand (COD) and 100% of the total suspended solids. The pilot scale design indicates that the AD-MEC and EC units would generate 1.4 times more energy than energy consumed through applying these novel technologies. These findings demonstration the applications of four technologies (HDC, AD, MEC, and EC) in an energy-efficient waste management approach, producing bioenergy and cleaner water for low-tier use, especially in areas lacking traditional waste treatment options. [Display omitted] • Novel technologies for energy and water treatment of food waste + blackwater. • HDC pretreatment had 51.6% more CH 4 production in 5 days than AD-only. • AD-MEC integration increased energy production by 12.7% compared AD-only. • Electrocoagulation at 15 V for 90 min removed 96.2% COD and 100% of solids. • A pilot scale AD-MEC design showed 1.4x more energy generated than energy input. [ABSTRACT FROM AUTHOR]

The Beijing-Tianjin-Hebei (BTH) mega-large urban agglomeration of China (CMUA) has significantly contributed to Chinese socioeconomic development. However, it faces severe shortages in the supply to meet the increasing demand of water, energy, and food resources (WEF). In order to safeguard the resource security of CMUA-BTH and the synergistic development of cities, and to compensate for the lack of dynamic analysis between urban agglomerations and WEF in previous studies. In this study, a coupled CMUA-WEF simulation model is developed based on the system dynamics approach. The model not only studies the three elements of WEF, supply and demand, but also conducts a comparative analysis of the three regions of BTH, and designs a total of four scenarios based on the possibility of future development, so as to facilitate the depiction of the trend of the WEF supply and demand system under different scenarios, and to provide theoretical basis for the government to formulate effective policy. The results show that: (1) Regarding demand, the aggregate demand for energy, food and water in the BTH will increase by about 3–5 times, 3 times, and 2 times, respectively, from 2000 to 2050, among which the total demand for energy will increase most significantly. In contrast, the variation of local resource supply side is small, which leads to the deterioration of resource security. (2) The risk of water shortage is the greatest in resource security, with less than 30% self-sufficiency in water security in all three regions. (3) Scenario analysis for CMUA-BTH indicates that "choking flow" (S3) yields more pronounced effects compared to "open source" (S2), and therefore adhering to the reduction of food waste, promoting energy-saving technologies, and intensifying water-saving measures can effectively reduce the risk of water shortages in the three regions. Optimal resource security in S4 increases Hebei's water pressure by 1.5%, alleviates Beijing's pressure by 7.3%, and the implementation of the Xiongan New Area and the new energy development policy can help realize the synergistic development of BTH and the inter-regional linkage. [ABSTRACT FROM AUTHOR]

In recent years, there has been an increased focus on researching food waste in the hospitality industry, which is crucial for helping industry to meet the Sustainable Development Goal (SDG) 12.3, which aims to halve food waste by 2030. This study identifies circular practices as a potential pathway to mitigate food waste, as these have a regenerative aim to prevent and reduce waste, preserve resources and protect the environment. A systematic literature review was conducted to identify, analyse, and summarise research on circular practices in the hospitality sector regarding food waste. The review identified 51 published articles. The study examined various aspects of the studies, including publication year, journals, geographical scope, type of establishment studied, research design, and research type. The review identified eight themes through conventional content analysis, which provided an overview of the current state of research on circular practices in the hospitality sector regarding food waste. The findings show that using different circular practices reduces food waste and encourages sustainable behaviours among customers. Further research is necessary to comprehend what drives and hinders customer engagement with circular practices related to food waste in the hospitality sector. To guide future research, we outline a research agenda highlighting opportunities and challenges in waste prevention in the hospitality sector. We also present implications for practice and research. • A systematic literature review was conducted to examine research on circular practices in the hospitality sector regarding food waste. • Most studies regarding circular practices and food waste focus on preventing, minimising, and recycling goals. • Further research is necessary to comprehend customer engagement with circular practices. • Insights for managers seeking to address food waste are presented, guided by the food waste hierarchy. [ABSTRACT FROM AUTHOR]

Biofuels and chemicals derived from wet food waste (FW) can serve as a strategy to significantly reduce emissions and mitigate environmental pollution while preventing the loss of valuable resources. Hydrothermal liquefaction (HTL) is one of the most promising thermochemical techniques for converting wet waste into crude oil-like products (biocrude). In this study, catalytic HTL of FW was carried out using cobalt (Co), magnesium (Mg), and cobalt-magnesium (Co–Mg) supported on ZSM-5 to produce high-quality biocrude. The impact of key operating parameters, such as reaction solvent, temperature, reaction holding time, and catalyst amount, was investigated. In comparison to non-catalytic liquefaction, catalytic liquefaction significantly improved the biocrude yield. The maximum biocrude yield (60.89 wt%) was achieved with bimetallic Co–Mg/ZSM-5 catalysts at 280 °C with 10 wt% of catalyst at a reaction time of 15 min. Various analytical methods, including GC-MS, FT-IR, CHNS, TGA, and NMR, were employed to identify the composition and quality of the biocrudes. Catalytic liquefaction with Co–Mg/ZSM-5 in an ethanol solvent resulted in a higher percentage of ester compounds (74.15%, area percentage). The biocrude obtained through the catalytic process had lower oxygen and nitrogen content, which led to a higher heating value (HHV). Biocrude quantification revealed the presence of 12.16 wt% of linoleic ester compounds. The concentration of total nitrogen (TN) in the catalytic aqueous phase was as high as 2.44 g/L, significantly greater than the 0.32 g/L found in the non-catalytic aqueous phase. Furthermore, the optimum Co–Mg/ZSM-5 catalyst demonstrated excellent reusability and stability in FW liquefaction. [Display omitted] • Co, Mg and Co–Mg/ZSM-5 metal catalytic effects were investigated on FW hydrothermal liquefaction. • Maximum biocrude yield (60.89 wt%) was found with Co–Mg/ZSM-5 catalyst. • Higher amount of ester compound (74.15%) was produced with catalytic HTL of FW. • Possible catalytic esterification reaction mechanism was illustrated. [ABSTRACT FROM AUTHOR]

Based on the high volume of research pertaining to household food waste (FW) generation, a significant proportion of existing studies present findings that lack comparability and general transferability, largely due to their confinement to individual countries or regions. Likewise, results frequently exhibit considerable variability and cross-study incongruities. Merging individual studies into broader scoping reviews can elucidate the underlying reasons for this variability between studies, enhance overall comparability and generalizability of findings, and subsequently expand overall applicability. The current scoping review and pooled analysis examined household FW generation data from high-income countries using the Population Concept Context (PCC) framework, identifying and analyzing empirical studies from 2010 to 2022. Overall, 56 studies from 24 countries were identified, resulting in a pooled mean FW volume of 42.86 kg/cap/yr. The Asia-Pacific region exhibited the highest mean FW volume (70.28 kg/cap/yr), while Europe had the lowest (34.45 kg/cap/yr). Within Europe, non-EU countries reported higher mean volumes (56.88 kg/cap/yr) than EU member states (34.33 kg/cap/yr). Methods involving self-measurement by householders recorded lower FW volumes compared to those measured by third parties (FW researchers). Fruits and vegetables were the most frequently discarded items, with a mean volume of 18.75 kg/cap/yr and 32.34% of total FW volumes. The presented review highlights the importance of considering study methodology, location, and FW composition when interpreting household FW data. It also serves a useful tool for designing household FW studies and improving the quality of data going forward. [ABSTRACT FROM AUTHOR]

Bread, the most consumed floury product in the world, is one of the most wasted food products across the food supply chain. Yet, there is a paucity of research examining the magnitude of bread waste and behavioural drivers associated with it at the household level. This study analyses the incidence, behavioural drivers and disposal pathways of bread waste using a sample of 1462 households in Australia and a 7-day electronic diary method. Behavioural drivers related to bread waste were modelled using logistic regression models. The findings suggest that bread rolls, sliced bread and flat bread are the three most wasted bread products in Australian households. Higher grocery shopping frequency, 'just-in-case' buying, family households with young children and takeaway meal ordering are associated with higher bread waste. Bread disposal pathway analysis revealed that 55% of bread and bakery products are discarded through general waste bins, highlighting the immense potential of utilising bread waste in industrial processes such as biofuel production. Addressing bread and bakery waste can significantly contribute to achieving the SDG12.3 goal of halving the per capita food waste by 2030. • Household bread waste behaviours and disposal pathways analysed. • Bread and bakery waste represent 12% of total edible food wasted. • Sliced bread, bread rolls and flatbread are the most commonly discarded breads. • Just-in-case buying, and family households are associated with high bread waste. • 55% of bread and bakery waste is discarded through general waste bins. [ABSTRACT FROM AUTHOR]

Biohythane, the promising gaseous biofuel, can be produced by the recirculated two-phase anaerobic digestion (R-TPAD). The effect of hydraulic retention time (HRT) as 30, 20 and 10 days on biohythane production via R-TPAD (recirculation ratio = 0.4) was investigated with co-digestion of food waste and paper waste. The results showed that HRTs of 30 and 20 days maintained stable performance for R-TPAD but HRT of 10 days led to the final decrease in biogas production. The failure in the end was attributed to the wash-out of microbes. The removal efficiencies for COD and carbohydrates were decreased by short HRTs while for VS it remained relatively stable at about 75.7 ± 4.0%. All through the operation, acidogenic phase and methanogenic phase were separated stably and butyrate pathway was the dominant pathway for hydrogen fermentation in the first stage. The microbial community in the first stage reached the highest diversity when total HRT was 20 days, where the hydrogen production rate was the highest. The genera Lactobacillus and Caproiciproducens kept dominating the dark fermentation in the acidogenic phase, and Ruminococcus and Methanosarcina were decreasing in the methanogenic phase. The biohythane yields were 411 mL/g-VS fed , 332 mL/g-VS fed and 253 mL/g-VS fed , respectively, where the H 2 contents were 18.4%, 14.7% and 8.8%, respectively. [Display omitted] • The R-TPAD system (R = 0.4) was operated for biohythane production. • R-TPAD operated under HRTs of 30 and 20 maintained stable performance. • Organic removals and biohythane yields were lowered by short HRTs. • Different microbial communities were identified by co-occurrence network. • Biohythane yields affected by different parameters were discussed. [ABSTRACT FROM AUTHOR]

In the present work, the effect of pure lactonic sophorolipids (SL) on the anaerobic digestion of biowaste was investigated. For this purpose, crude SL were produced from organic waste (a mixture of molasses and winterization oil cake) through solid-state fermentation (SSF) in a 22L pilot-scale aerobic bioreactor using the yeast Starmerella bombicola as SL-producing microorganism. The crude material extracted from the SSF exhaust solid contained several forms of SL and it was purified using High-Performance Liquid Chromatography (HPLC) and characterized by means of Liquid Chromatography-Mass Spectrometry (LC-MS) yielding a high-purity C18 lactonic SL (>99%). This pure SL was used to enhance the batch anaerobic digestion of source-selected biowaste, mainly composed by kitchen waste. The best dosage of SL was in the range of 0.02–0.04 g SL/g TS, with an increment of methane yield of 41% in NmL/g VS. The presence of SL did not significantly alter the structure of the microbial community or general biodiversity. In summary, we propose a circular approach for waste valorisation in which different organic waste streams are combined in a biorefinery-like configuration, where the solid-state fermentation is used to produce SL and results in an enhanced bioenergy production. [Display omitted] • Sophorolipids were obtained from solid-state fermentation of molasses and oily waste. • Starmerella bombicola was used as yeast to produce sophorolipids in a 22L bioreactor. • The mixture of produced sophorolipids contained several configurations. • A lactonic form of sophorolipid (C18:1) was purified (>99%) from the crude extract. • This form increased up to 40% the methane yield in the biowaste anaerobic digestion. [ABSTRACT FROM AUTHOR]

Wasted food (WF) and the associated waste derived from young adults have gained increased attention due to their rising quantity and negative environmental impacts; however, WF reduction measures are still scare. To address this gap, we conducted a case study (Wuhan) targeted at typical young adults (e.g., university students) using the direct weighing method (1872 samples), field investigation (195990 samples), and a questionnaire survey (799 samples). Owing to the low "Clean your plate" (CYP) rate (48 ± 36% per meal) and the high canteen takeout rate (43 ± 22% per meal) generated by the surveyed students, the investigated canteens in Wuhan produced 63 thousand metric tons (TMt) of canteen waste and 198 TMt CO 2 e during the life cycle stage in 2022. Food was primarily wasted due to food quantity (e.g., over-purchase of food) and quality (e.g., poor taste), and packaging waste was generated due to canteen takeout (PW_CT). We suggest the adoption of an online waste reduction platform to effectively reduce WF and PW_CT, which was designed with two mitigation solutions (CYP, "Over-Purchasing Reminder" [OPR], and "Canceling Packaging Option" [CPO] modules for SI; CYP, OPR, and "Sharing Tableware Option" [STO] modules for SII). When in operation, the platform helped consumers prevent the generation of approximately 42 and 43 TMt of canteen waste generated for SI and SII, respectively. This was accompanied by the maximal economic value (saving 73 million USD for SI) and the maximal climate benefits (143 TMt CO 2 e mitigation for SII). [Display omitted] • A considerably amount of wasted food generated by university students accompanied by low "Clean your plate" rate. • The high canteen takeout rate generated by students led to a large amount of packaging waste. • Online waste reduction (OWR) platform was targeted wasted food and packaging waste from university canteens. • The significance of OWR platform was proved by its environmental benefit and economical values. [ABSTRACT FROM AUTHOR]

Polystyrene (PS) is an important raw material of food packages, and its induced microplastics (MPs) inevitably enter into the food waste (FW) with mechanical or hydrothermal pretreatment, which may affect the FW anaerobic digestion (AD). However, the different microbial responses to PS MPs in AD system have rarely been reported at varying PS MPs levels. In this study, the trade-off between positive and negative effects of PS MPs on syntrophic methanogenesis in AD for FW treatment was investigated when the dosage varied from 10 to 200 mg/L. The results showed that methane (CH 4) yield was upgraded by 4.72% at a lower PS MPs concentration (25 mg/L) compared with the control reactor without PS MPs dosing. In contrast, it would be inhibited by 10.13% when PS MPs concentration increased to 100 mg/L. More secretion of extracellular polymeric substances was the main reason for methanogenic metabolism enhancement at lower dosages of PS MPs due to its characteristics of cell-protection and electron transfer facilitation. Furthermore, the higher abundance of genes regarding superoxide dismutase and catalase in the reactor with PS MPs of 25 mg/L could impede reactive oxygen species formation and alleviate its toxicity. The findings of the study provide a comprehensive understanding of the promotion and inhibition mechamisms of syntrophic metabolism in the AD process by PS MPs and their released substances at varying concentrations. [Display omitted] • The CH 4 yield of food waste was improved by 4.72% at PS MPs of 25 mg/L. • ROS induced by PS MPs at 100 mg/L led to methanogenesis inhibition. • PS MPs promoted electroactivity of EPS and interspecies electron transfer capacity. • PS MPs at 25 mg/L increased enzymatic antioxidants (SOD and CAT) to neutralize ROS. [ABSTRACT FROM AUTHOR]

Repurposing of food waste (FW) affords an alternate waste management strategy and sustainable product yield. Thus, this study proposed an integrated biorefinery approach, repurposing pretreated FW hydrolysate for microalgae cultivation and utilizing residual solids for biomethane recovery. FW biomass with different solubilization ranging from (10–15 to 60–65%) obtained during surfactant coupled disperser pretreatment was used as a substrate for microalgae (Chlorella vulgaris) cultivation. A higher microalgae biomass productivity of 0.87 ± 0.003 g/g substrate was obtained from the FW hydrolysate with 40–45% solubilization. The microalgae cultivated in FW hydrolysate with 40–45% solubilization yielded a higher protein, carbohydrate, and lipid accumulation of 380 ± 20 mg/g, 480 ± 30 mg/g and 360 ± 15 mg/g. Besides, the methanogenesis process showed a higher methane yield of 0.294 ± 0.003 L/g COD utilizing residual solids of pretreated food waste as substrate. This integrated biorefinery provides a sustainable platform for completely valorizing food waste biomass and recovery of multiple products. [Display omitted] • Repurposing of food waste is an alternate sustainable waste management strategy. • Algal biomass of 0.87 ± 0.003 g/g was obtained from 40 to 45% solubilized food waste. • More biopolymer was noted in microalgae cultivated in 40–45% solubilized food waste. • Higher methane of 0.294 ± 0.003 L/g COD was obtained in 40–45% solubilized residues. [ABSTRACT FROM AUTHOR]

The technological advancements in the bio-conversion of food waste (FW) into biogas signify substantial advancements in the field of waste management. However, persistent operational challenges like rapid acidification and difficulties in maintaining the C/N ratio in mono-digestion remain, despite extensive research efforts. The present study aims to evaluate the reactor performance in co-digestion, specifically using a 1:1 ratio of unavoidable food waste (UAFW) and avoidable food waste (AFW), with the addition of calcined eggshells as an additive. Further, the study employs Ordinary Least Square (OLS) regression modeling to predict the biogas production from the co-digestion process. The experimental process involves ultrasonication pretreatment, focusing on calcined eggshells for their ability to preserve carbohydrates via Ca(OH) 2 , an alkaline material. The semi-continuous operation of the reactor spanned for 120 days and was divided into three phases with varying Organic Loading Rates (OLR) from 0.6 to 2.2 gVS/l/d. Characterization studies such as SEM, FTIR and TGA-DTA were performed to validate the pretreatment method and addition of egg-shells. Results indicated increased OLR led to higher Volatile Solids (VS) reduction. This was attributed to the calcined eggshells' role in adsorbing NH 4 + and NO 3 − ions while maintaining pH levels, resulting in significantly higher biogas production. The multiple regression models used in the study yielded promising results, surpassing simple linear regression, with an adjusted R-squared value > 0.9 and p-value <0.05. The model effectively anticipated the specific methane yield, demonstrating the capability to improve energy production by co-digesting AFW and UAFW. The study presents an opportunity to divert organic waste from landfills, reduce greenhouse gas emissions, and promote sustainable waste management by using bio-waste additives, reducing reliance upon synthetic chemicals. [Display omitted] [ABSTRACT FROM AUTHOR]

Food redistribution is increasingly recognized as a key strategy for tackling food waste and improving food security. However, a comprehensive assessment of its environmental impacts remains a challenge. This study fills this gap by investigating the role of food redistribution in minimizing waste, reducing production pressures, and mitigating the environmental impacts of the agri-food chain. In particular, this research focuses on mapping the flow of recovered food within the Ortomercato system, Italy's largest fruit and vegetable wholesale market, by third sector associations. A comprehensive cradle-to-grave life cycle assessment was conducted to quantify the recovered fruit and vegetable products, assess their environmental impact, and estimate the associated environmental credits through the prevention of food waste. The findings indicate that the production phase has the largest environmental impact, accounting on average for 63% of the total impact. The study employs a net balance approach to demonstrate the success of food recovery efforts, which have saved over 136 tonnes of food from the market over a 49-day period and generated environmental credits equivalent to 169 tonnes of CO 2 eq. per year. These results highlight the environmental impact of food redistribution and provide insights for operational optimization and the establishment of an environmental budget for the system. Furthermore, the potential for regulating these environmental credits and promoting the benefits of food redistribution through public channels is highlighted. While the research addresses the mapping of food flows and their environmental impacts, there is a significant gap in the assessment of the socio-economic impacts associated with food redistribution. Further research is needed to understand how this practice affects local communities, economies and social dynamics, and to contribute to a more comprehensive assessment of its effectiveness. • LCA was conducted on intercepted surpluses of fruits and vegetables. • The key flows defining the Third Sector operations in Ortomercato were outlined. • RECUP saved 136.84 tons of fresh produce in 49 days of operation in Ortomercato. • Environmental Impact Balance predicts credits from surplus redistribution. • RECUP's activity generated 169 tons of CO 2 eq environmental carbon credits annually. [ABSTRACT FROM AUTHOR]

Hydrothermal conversion technology is a promising technique for resource utilization. In this study, the influence of reaction conditions on the distribution of hydrothermal conversion products was investigated, and the resource utilization methods of all components of hydrothermal conversion products were discussed. The results showed that the highest bio-oil yield was obtained at 310 °C, which was 36.75 %. The higher heating value and energy recovery rate of bio-oil can reach 39.68 MJ/kg and 78.55 % respectively. And it had great potential as an alternative fuel. When wheat seeds cultured by aqueous were diluted 100 times at 310 °C with GI ≥ 80 %, the phytotoxicity disappears. At this time, the contents of total nitrogen, total phosphorus, and total potassium were 1234.80, 150.34, and 1640.36 mg/L respectively, and the heavy metal content was lower than the national standard for foliar fertilizer. The optimal conditions for biochar to adsorb methylene blue were adsorbent dose 2 g/L, 180 rpm, temperature 70 °C, and time 120 min; The gas phase yield increased with the increase of temperature (0.15–7.45 %). The yield at 310 °C was 2.76 %. The main component of the gas phase was CO 2 , accounting for 93.71–97.92 %. The innovation of this study was that food waste can be converted into bio-oil through high-temperature hydrothermal reaction, achieving energy recovery. The aqueous phase product of hydrothermal conversion was used as water-soluble liquid fertilizer, achieving resource utilization. At the same time, the reaction was carried out under high temperature and pressure, which can completely kill pathogens in food waste and has extremely high biological safety. [Display omitted] • Comprehensive resource utilization of the hydrothermal conversion of food waste. • The fractions in the low boiling point range (<343 °C) can reach up to 66.98 %. • The aqueous phase has potential fertilizer value for wheat seeds culture. • The biochar can be used as an adsorbent of BM. [ABSTRACT FROM AUTHOR]

Hydrochar aging may mitigate the adverse effects of direct hydrochar application on plant growth. However, little is known about the strategies for accelerating aging process and the microbiological mechanisms involved. This study explored the effects of three aging strategies, including the addition of straw and efficient-degrading microorganisms, on the aging processes of food waste-derived hydrochar, and identified the key microbial drivers. The bacterial and fungal sequencing was performed to estimate the species composition in hydrochar at different aging periods (i.e., day 1, 7, 14 and 35). The results showed that the addition of straw and microbial inoculum improved the maximum reaction temperature by 13%, and shortened the aging time by ∼30%. Three bacterial guilds, mainly including Bacillus -like species, were identified that showed significant correlations with the nitrogen and phosphorus dynamics during aging. This study demonstrates the feasibility of manipulating key microbial guilds artificially to achieve efficient harmless-treatment of hydrochar. [Display omitted] • Straw and microbial inoculum addition reduced aging duration by 30%. • Microbial inoculum addition increases the aging reaction temperature by 13%. • Bacteria, rather than fungi, play the critical role in hydrochar aging. • Bacillus and related species drive nitrogen and phosphorus cycles of aging. [ABSTRACT FROM AUTHOR]

Reduction of food waste is an important element of the sustainable transformation of food systems. This study focused on food waste quantification, its causes, and perception in 5 territories: North Hessia (Germany), Cilento Bio-District (Italy), Kenitra (Morocco), Warsaw (Poland), Copenhagen (Denmark) with the main objective of assessing whether different cultures affected the levels and the profiles of household food waste. A validated questionnaire was used to assess the quantities and typologies of food waste (completely unused, partially used, meal leftovers, leftovers after storing). In addition, the reasons for food waste and how food waste was perceived were investigated. In a sample of 2154 respondents, the level of still edible food that was wasted amounted to 399 g per family per week, equivalent to 153 g per capita. Kenitra showed the highest amount of FW per household (539 g), but the lowest amount of food waste per capita (125 g). Citizens of rural communities, e.g., Cilento Bio-District (136 g), North Hessia Federal State (132 g), and Kenitra (125 g), had more effective food waste prevention practices than citizens of urban areas, e.g., Copenhagen (201 g) and Warsaw (179 g). Family size was identified as a significant factor in FW generation, with households having 5 or more members showing lower FW per capita (85 g) than single-member families (309 g). The study underscores the need for tailored strategies to reduce FW considering the above-reported territorial differences. [Display omitted] • The food waste regional differences demonstrated the need for targeted actions. • Rural areas (Cilento Bio-District,136g; North Hessia,132g; Kenitra,125g) waste less than urban (Copenhagen,201g; Warsaw,179g). • Families with 5 or more members wasted less food per capita (85 g) than 1-member families (309 g). • Awareness of food waste consequences was a motivating factor for reducing waste. • Difficulties in reusing leftovers and managing food were barriers to waste reduction. [ABSTRACT FROM AUTHOR]

Convenience foods have wide-reaching impacts on various areas of sustainability. However, research typically focuses on environmental issues, often overlooking other sustainability issues. Design research, specifically Food-to-Go design research, focuses solely on specific environmental behaviours, such as users' packaging use, food waste, and overall circular behaviours regarding food. This study aims to define areas of Food-to-Go-style convenience foods that have a significant correlation with human issues, to develop a future design research agenda that looks at and integrates the variety of sustainability issues associated with Food-to-Go. The study accomplishes this through a literature review and meta-analysis synthesising the various impacts of convenience food across areas, such as environmental sustainability, human health, and sociological studies of food consumption. This paper concludes that although current research includes many of the areas mentioned above, there is also a previously unidentified opportunity for psychological wellbeing investigation. • There is not enough research into the social sustainability impacts of convenience food. • Convenience food research is often siloed into discrete aspects of sustainability. • There is evidence both for and against convenience food being associated with the likelihood of obesity. • The odds of experiencing several health issues are positively associated with different types of convenience food. [ABSTRACT FROM AUTHOR]

Food loss and waste (FLW) reduction presents a major opportunity for enhancing the sustainability and resilience of the food supply chain. However, the lack of evidence regarding the scale and origins of FLW hinder determination of its environmental impact and prioritisation of mitigation action. We herein conducted a study to quantify FLW in the UK horticulture supply chain, and estimate its environmental impact as assessed through CO 2 equivalent (CO 2 e) emissions. Through a metanalysis of existing literature supplemented with stakeholder engagement, we estimated that 2.4 Mt of fresh produce FLW is generated annually between farm gate and retail for home-grown and imported produce, representing 36% of total supply. FLW was perceived as an inevitable economic risk rather than a sustainability issue, driven by economic factors (e.g. labour shortage, price protectionism). The lack of economic incentives for FLW recovery (e.g. alternative processing) further compound FLW. Our results reveal that FLW contributes 1.7 Mt CO 2 e annually, constituting 27.2% of the total emissions of the fresh produce supply chain. Resource-intensive production, prolonged storage and complex handling needs generates substantial energy demand and concordant environmental impacts. The current over-reliance on cold chain management should be re-examined to disentangle the FLW-energy-environment nexus, especially given that the effects of global warming on the horticulture supply chain has yet to be examined. To effectively mitigate FLW, a holistic approach is imperative, encompassing policy and consumer-level changes alongside development of novel postharvest management strategies. [ABSTRACT FROM AUTHOR]

In Malaysia, the challenge of managing the burgeoning volume of food waste in an environmentally sustainable manner is critical, given the country's rapid urbanization and the resulting increase in waste. This review article critically examines contemporary efforts and technologies in food waste management, focusing on anaerobic digestion (AD), incineration, and the emerging Hydrothermal Carbonization (HTC) technology, emphasizing their application within the Malaysian context. It is observed that landfills, currently the predominant method for waste disposal, contribute significantly to environmental degradation, highlighting an urgent need for sustainable alternatives. AD is identified as a beneficial approach, offering the dual advantages of waste volume reduction and biogas production; however, it is hindered by technical and economic challenges. Incineration, while effective in waste reduction and energy recovery, raises concerns regarding potential emissions of carcinogenic substances and its economic feasibility. The novel HTC technology, on the other hand, presents a promising avenue for converting food waste into Hydrochar, a carbon-rich product, demonstrating the potential for environmental sustainability and economic viability. The review underscores the imperative of optimizing these technologies to suit Malaysia's specific conditions, suggesting that future research should focus on enhancing HTC's application. This comprehensive evaluation aims to contribute to advancing sustainable food waste management practices, advocating for integrated solutions that are environmentally responsible, economically feasible, and socially acceptable. [Display omitted] • Malaysia's food waste at 16688 t/day; 80% landfill reliance. • Anaerobic digestion: potential vs. high investment. • Incineration reduces waste but raises cost, emissions. • Hydrothermal Carbonization (HTC) emerges as future solution. • Need for tailored solutions in Malaysia's unique context. [ABSTRACT FROM AUTHOR]

Volatile organic compounds (VOCs) and pathogens that are generated during fermentation of food waste by microorganisms have caused odor annoyance and health risks. In this work, the evolution profiles of them during aerobic decomposition of inter-type and intra-type food waste were compared in laboratory-controlled reactors for three months. The emission fluxes of VOCs reached peak on the 10th day (except fish waste), then decreased sharply until leveled off. For vegetable waste, watercress emitted higher concentrations (2.5 × 104−2.4 × 106 μg/m3) and emission fluxes of VOCs (5.4−508 μg kg−1·h−1) than pepper and onion. While for meat waste, the emitted VOCs from fish (1.4 × 105−8.4 × 106 μg/m3 and 68.4–4.3 × 103 μg kg−1·h−1) were higher than chicken and pork. Dimethyl trisulfide (DMTS) and ethyl acetate as well as DMTS and methyl methacrylate were dominant oxygenated VOCs and volatile organic sulfur compounds in vegetable and meat wastes, respectively. The odor from the leachate was attributed to the emitted sulfur-containing compounds. The main fermented bacteria in intra-type food waste were highly similar, but differed greatly between the inter-type food waste with Lactobacillus and Comamonas as well as Peptoniphilus and Wohlfahrtiimonas as the major fermented bacteria in vegetable and meat wastes, respectively. Significant correlations between microbial community and VOCs including ethyl acetate, DMDS and 2-butanone were observed. As predicted by functional annotation of prokaryotic taxa (FAPROTAX), Lactobacillus and Bacteroides were correlated with the respiration of sulfur-containing compounds and hydrocarbon degradation, respectively, suggesting that production of VOCs was contributed mainly by bacteria communities. Pathogenicity of food waste was mainly due to Enterococcus , Proteobacteria , Mycobacterium and Salmonella. Our results are conductive to develop countermeasures to reduce VOC emission during food waste decomposition. [Display omitted] • VOSCs and OVOCs were the dominant VOCs emitted from food waste fermentation. • The released unpleasant odor was attributed to the sulfur-containing compounds. • Intra-type and inter-type food waste had similar and different bacterial communities. • Ethyl acetate, 2-butanone, VOSCs were correlated with microbial communities. • Enterococcus, Proteobacteria, Mycobacterium , and Salmonella were the main pathogens. [ABSTRACT FROM AUTHOR]

Lipid content is an essential indicator which affects the operation performance and efficiency of an anaerobic digestion system. This study investigated the relationship between system stability and lipid degradation during mesophilic anaerobic digestion process of lipid-rich food waste. As the experiment designed, the hydraulic retention time was 30 days and influent total solid (TS) concentration of the substrates was kept at 10 %, in which lipid content gradually increased from 10 % to 60 % (on the TS basis). The anaerobic digestion process proceeded successfully, achieving a methane yield of 587 mL/g-VS (volatile solids) at lipid/TS ratio of 50 %. However, the system collapsed after the lipid/TS ratio exceeded 50 %. It was found that the accumulation of long-chain fatty acid was not the primary factor leading to system failure, as the total concentration remained below 500 mg/L even at lipid/TS ratio of 60 %. Instead, the C/N ratios resulting from different lipid contents significantly impacted system stability. As lipid/TS ratio increased to 60 %, the C/N ratio of substrate reached 45.47, causing system failure due to an efficiency imbalance between alkalinity production and VFAs accumulation. The mechanism was illustrated by carbon and nitrogen distributions. Additionally, the synergistic effect between lipids and food waste was also discussed, peaking at lipid/TS ratio of 40 %. These results highlighted that the C/N ratio had more prominent impacts on system stability than long-chain fatty acids accumulation during the designed lipid-rich food waste anaerobic digestion process. [Display omitted] • Food waste anaerobic digestion was conducted with lipids content up to 50%. • Long-chain fatty acids were not accumulated during the long-term operation process. • A carbon/nitrogen ratio of 45.47 led to alkalinity deficiency and system failure. • Synergistic effect was clarified by carbon and nitrogen distributions. [ABSTRACT FROM AUTHOR]

Interventions on consumer food waste behaviours are an effective way to reduce food waste as well as negative environmental impacts. Informational interventions are currently popular. However, the effectiveness of informational interventions is controversial and has not been evaluated on a large scale in practice. This study tested an 11-week randomized controlled trial in the food service industry covering 11 types of food waste and consumption, using a propensity score matching method between experimental (N = 712) and control groups (N = 591) to assess the effectiveness of different types of information (instructive VS guilt-based VS coupled) interventions. It was found that there was a significant reduction of 10.69g (10%) in the total amount of food waste after the informational intervention. Instructive information had a significant impact on food waste reduction, reducing 20% of waste at the consumption stage, followed by guilt-based (4%) and coupled (3%) information. The instructive-type intervention was found to be the most effective for reducing waste in pork, roots and tubers, cereals, and legumes, while the guilt-type intervention was found to be the most effective for reducing waste in eggs. Differences in terms of consumers' gender, education, weight, and amount spent were confirmed. In addition, the informational intervention had a spillover effect on food consumption, with instructive information significantly increasing food consumption by 23.82g (37%). This study shows that informational interventions, especially instructive information, are effective and reveals differences between segments. It also emphasizes the significance of considering the type of information and food categories for both the food service industry and national interventions. • Confirmation that informational interventions are effective. • Instructive information is more effective than guilt-based information. • Instructive information significantly increased food consumption. • Informational intervention had the different effect on different consumers. [ABSTRACT FROM AUTHOR]

In the current global landscape, food loss and waste (FLW) persist as a significant challenge, accounting for one-third of global food production and directly impacting 700 million individuals. Beyond its social ramifications, FLW incurs substantial economic costs and raises environmental and ethical concerns. To address this issue, our paper presents a comprehensive systematic overview within operations management, offering a framework that delineates diverse supply chain types, defines FLW, examines its multifaceted impacts, and outlines reduction strategies. Emphasizing a holistic perspective, we utilize various case study approaches to shed light on the global implications of FLW, aiming to contribute to ongoing research endeavors. In exploring the depth of FLW, we build upon two foundational premises: the actions taken by rational actors towards FLW reduction hinge on the balance between benefits and costs, guiding policy formulation. Effective policies necessitate a thorough understanding of synergies, potential unintended consequences and trade-offs. The absence of comprehensive information on FLW leads to both excessive and insufficient rates of FLW. Justifying public intervention lies in its potential to enhance food security, efficiency, and environmental sustainability, albeit quantifying these effects poses challenges. Our overview paper identifies key challenges in FLW policies, encompassing measurement, quantification, interdependencies within the and trade-offs, and value chain in food policy objectives. Despite these challenges, the paper guides the enhancement of loss measurement for targeted interventions, emphasizing investments in policies that foster a conducive business environment and government-led initiatives in awareness and incentive modification. The study also sheds light on crucial gaps in knowledge, including data deficiencies and variability in estimates, calling for standardized data collection methodologies and targeted research initiatives. By addressing these gaps and emphasizing collaborative efforts, this research contributes to a nuanced understanding of FLW, advocating for improved strategies to tackle this multifaceted issue. • Comprehensive Ops Framework: Presents systematic framework for FLW reduction in supply chains. • Multifaceted FLW Impacts: Explores economic, environmental, and social impacts. • Urgent Data Gaps: Emphasizes need for current data on FLW, especially in BRICS nations. • Culture-Specific Solutions: Highlights importance of tailored innovations for waste reduction. • Climate Nexus and Renewable Energy Integration: Explores FLW, climate change, and renewable energy synergy for sustainable, low-carbon paths. [ABSTRACT FROM AUTHOR]

The world is evolving towards sustainability and optimum resource management, with a rapid evolution towards a circular economy (CE). The focus on sustainability in the food and beverage (FoodBev) sector is a priority due to the close association and dependency on natural resources. The evolution of digitalization has accelerated sustainable development of the FoodBev sector and helped preserve sectorial natural resources dependencies. Digital skills are a key component of sustainable development, as skills are used to identify and implement sustainable solutions. Digitalization and the CE in the FoodBev sector are considered critical solutions for food waste and food loss, and potential drivers of sustainability. This study seeks to deploy a smart value chain tool for food waste and food loss management, and a digital mechanism for the sustainability of the FoodBev sector. The research team designs, develops, and demonstrates a python-enabled digital toolset, configured to construct a specific global search for sustainable alternates for waste and other streams of the FoodBev industry. The toolset adopts a combination of Artificial Intelligence techniques including data analytics and Natural Language Processing. The results provide for rapid technological alternatives identification for the sector. The paper provides technological alternatives for 18 FoodBev value streams. [ABSTRACT FROM AUTHOR]

Understanding how municipal solid waste (MSW) classification influences the physiochemical properties and incineration emission characteristics of MSW is imperative for sustainable waste management. To investigate how long-term changes in the composition and physical properties of MSW resulting from MSW classification affect the emissions of polychlorinated dibenzo-p-dioxins/dibenzofurans (PCDD/Fs) and multiple flue gas pollutants, a five-year experiment (2018–2022) was conducted in a full-scale MSW incinerator in Shenzhen City, China. After MSW classification, the food waste in MSW was substantially reduced while the paper, textile, and wood components were notably increased. MSW classification also remarkably decreased the water and chlorine contents of MSW while concomitantly increasing the wet-based calorific value, sulfur content, and nitrogen content. Consequently, the PCDD/Fs emissions declined from 106.7 ng I-TEQ/t MSW in 2018 to 26.0 ng I-TEQ/t MSW in 2022. Moreover, a process-tracing experiment demonstrated noticeable decreases in PCDD/F synthesis in the post-combustion area, with mass-reduction efficiencies of 23.6 %–95.4 %. In a correlation analysis, the PCDD/F emissions were significantly positively correlated with food waste, water content, and chlorine and negatively correlated with the wet-based calorific value and nitrogen content. Furthermore, MSW classification reduced the emissions of conventional flue gas pollutants (SO 2 , CO, and HCl) and multiple heavy metals (total sum of Sb, As, Pb, Cr, Co, Cu, Mn, and Ni). In summary, the long-term study demonstrated that MSW classification can feasibly separate incombustible waste, improve combustion quality, and reduce pollutant emissions from sources. These findings offer practical guidance for promoting MSW classification. [Display omitted] • MSW classification remarkably changes composition and physical properties of MSW. • MSW classification mitigates PCDD/F emission from 106.7 to 26.0 ng I-TEQ/t MSW. • MSW classification effectively reduces the emission of various flue gas pollutants. • The long-term experiment demonstrated the feasibility of MSW classification. [ABSTRACT FROM AUTHOR]

One of the very promising ways to improve a restaurant's eco-efficiency consists of implementing food waste reduction strategies (FWRSs) to reduce the costs and environmental impacts associated with food waste (FW). However, several factors can hamper the implementation of FWRSs, limiting a restaurant's ability to become more sustainable. Hence, the aim of this study is to identify the factors that facilitate or limit the implementation of FWRSs in independent restaurants. This will enable restaurateurs to choose the most appropriate FWRSs to implement, not only in terms of the potential economic and environmental benefits that can be achieved but also in terms of implementation feasibility, to ensure their sustainability. To achieve this, semi-structured interviews were conducted with owners, managers and chefs of independent restaurants in Quebec, Canada. They were questioned on several topics related to their perception of FW, eco-efficiency and FWRSs as well as their experiences in implementing FWRSs. The results allowed the identification of 12 factors affecting the implementation of FWRSs, which were analyzed and categorized according to social practice theory. These factors include consumer perception, management, planning and organizational skills as well as labor and food costs. Then, the factors were linked to the characteristics of the restaurants studied to identify the most promising ways to operationalize the reduction of FW according to the restaurant type. To this end, two approaches were raised: a preventive approach aimed at reducing FW at source, by adopting a limited fixed-time menu for example, and a corrective approach aimed at reusing FW to give it a second life. • The adoption of suitable FW reduction strategies maximizes restaurants' eco-efficiency • 12 factors affecting FW reduction strategies implementation were raised • These factors differ according to restaurants' characteristics • A preventive approach to reduce FW is to be favored for family/casual restaurant • Both a preventive and corrective approach can be adopted in fine dining restaurants [ABSTRACT FROM AUTHOR]

Short-term high-temperature pretreatment helps accelerate the composting process and improve compost product quality. The aim of this research was to clarify the role of high-temperature pretreatment compost (PHC) on soil and plant growth. We conducted an experiment in which PHC, traditional compost (PTC), and high-temperature pretreatment food waste (PFW) were used as organic amendments (OA). Each type of compost was mixed into purple soil at mass ratios of 3, 5, 10, and 20% to establish a soil-compost mixture; they were then used in pot experiments with Lolium perenne L. Plant growth-promoting effects were stronger in the three experimental groups with 10% OA than in groups with other mixing ratios (p < 0.05). Plant growth-promoting effects were strongest in the experimental group with 10% PHC, and Lolium perenne L. biomass, the chlorophyll content, and plant height were 1.1–1.3 times higher in this group than in the PTC and PFW groups. Soil physicochemical analyses revealed that OA at various mixing ratios could enhance soil nutrient levels, the humification degree, and enzyme activity, and the strength of the positive effects increased with the mixing ratio. The most pronounced soil amendment effects were observed in the PHC group at all mixing ratios (p < 0.05). Microbial analysis revealed that both the microbial diversity and relative abundances of unclassified_f_Rhizobiaceae and Terrimonas were significantly higher in the 10% PHC group than in the 10% PTC and PFW groups (p < 0.01). Correlation analyses indicated that urease, peroxidase, and sucrase activities were positively correlated with plant growth indexes. The correlation coefficients of unclassified_f_Rhizobiaceae with urease and Terrimonas with peroxidase and sucrase were 0.997, 0.878, and 0.863, respectively. PHC can promote plant growth by altering the dominant microbial communities and enzyme activity in the soil. This study provides a theoretical basis for the application of high-temperature pretreated compost products. [Display omitted] • The effects of organic amendments on soil properties and plant growth were compared. • High-temperature pretreatment compost most favored soil health and plant growth. • Soil nutrient content was positively related to the organic amendment blending ratio. • Plant growth was optimized at a 10% organic amendment blending ratio. • Plant growth was affected by dominant microflora and soil enzyme activity variation. [ABSTRACT FROM AUTHOR]

Addressing the global challenge of food waste, this research delves into the assessment of an on-site food waste treatment solution through a full-scale decentralized anaerobic digester (AD) system, specifically deployed at a Singapore hawker centre. Demonstrating efficiency in Singapore's tropical climate (29 °C) without external heating, the 10.8 m³ digester exhibited resilience over 234 days, navigating through real-world fluctuations in average organic loading rates ranging from 0.07 ± 0.02 to 0.81 ± 0.38 kgVS/(m3d). The normalized specific biogas production averaged 0.70 ± 0.48 m3/kgVS, accompanied by a methane concentration of 56.9 ± 2.9%. During peak performance, with an organic loading rate of 1.1 kgVS/(m3d), the system achieved an impressive volumetric biogas production rate of 1.18 m3biogas/m3reactor, equivalent to 1.1 m3/kgVS of specific biogas production per day. The energy assessment revealed consumption rates of 0.57–0.97 m3/kWh, positioning it comparably with commercialized biogas technologies in China and Taiwan. In the realm of microbiome composition, the prevalence of hydrogenotrophic methanogens, including Methanomicrobia, Thermoplasmata , and Nanoarchaeia , is notable. These methanogens showcase a remarkable tolerance to acetate, surpassing common aceticlastic methanogens by 11 times, thereby playing a pivotal role in enhancing the stability of the AD system over extended periods. On the economic front, the present AD system yielded losses ranging from SG$552,434 to SG$742,919, primarily due to a low payback period and substantial investment costs. Profitability becomes a possibility if there are significant reductions in capital costs and operator salaries. The challenges encountered during the operation of this decentralized system, along with the corresponding mitigation measures, are thoroughly discussed. Positioned as a promising test-bedding model, this application underscores its technical feasibility potential for sustainable food waste management through AD technology in Singapore. It stands as a replicable prototype, contributing to closing the food waste loop and advancing the bioeconomy. [Display omitted] • A decentralized AD system was set up to convert food waste to energy in Singapore. • The AD system was operated on a long-term basis, 234 days of real operational data. • The AD system produced an average of 0.70 m3biogas/kgVS with 56.9% CH 4 content. • Best operational state energy balance attained 0.57–0.97 m3/kWh consumption rate. [ABSTRACT FROM AUTHOR]

Food waste has a significant impact on the environment, national economies, and food security, necessitating appropriate action by policymakers. Food waste is prevalent among the young generation, so it becomes prudent to understand their food waste behaviour, involving the identification and evaluation of significant variables. This study seeks to comprehend their food waste behaviour as well as their intent to engage in such behaviour. An extended theory of planned behaviour was utilized to achieve the objectives, and a conceptual model and hypotheses were formulated accordingly. Some extensive constructs were incorporated with the theory of planned behaviour's major constructs. Data was collected via a questionnaire survey from a sample of 345 students at the University of Kashmir, Srinagar, India to identify relevant factors. Correlation analysis and regression analysis (linear regression model) were used to better understand the relationship between various variables. The intention of students not to waste food was successfully predicted using the extended theory of planned behaviour. Our study's findings revealed that several factors, such as one's attitude, behavioural control, knowledge about food waste, moral standards, eating habits, and leftover reuse routine, have a significant influence (p < 0.01) on students' desire to avoid food waste and explain 68.6% of the variance in intention to not waste food. Knowledge about food waste was by far the most significant factor associated (with max. β coefficient) with the desire not to waste food. Subjective norms did not reach statistical significance (p > 0.01) and could therefore not be used to predict intentions. The research highlights effective strategies to reduce food waste among youth by outlining the most impactful factors that explain the intention to waste less food and thus contribute to addressing the global issue of food waste. [Display omitted] [ABSTRACT FROM AUTHOR]

In a linear economy, consumers typically dispose end-of-life products which are eventually incinerated or landfilled. Digital platforms could unlock rich waste reutilization opportunities and economic benefits by connecting the waste producers with potential waste buyers in online marketplaces. While previous studies mostly focus on input-output matching, this study proposes a decision support system that can be incorporated to an online marketplace to optimize the waste trading based on economic considerations. Moreover, the decision support system could facilitate higher level decisions such as capacity planning and incentive design. Based on a case study on Singapore's organic waste streams, the waste trading platform presents economic benefits for agents that sell their waste. Additionally, enforcing waste reutilization targets would require relevant policy support in terms of incentives or levies, where the levies can be implemented as co-payment rate for the agents. For instance, results showed that when the food waste reutilization target is set as 6 t/d, increasing the co-payment rate from 0 to 20% allows the waste trading network to be self-sustaining without external funding. Finally, sensitivity analyses show that collecting more waste records in the database helps in optimizing the investment decisions, preferably when the number of records exceeds 64. [ABSTRACT FROM AUTHOR]

Medium-chain carboxylates such as caproic acid, have a plethora of applications, ranging from food additives to bioplastics, and can be produced via microbial chain elongation (CE), a process that can be more sustainable than conventional production routes. During CE short fatty acids accept electrons from donors as lactate or ethanol elongating into medium-chain carboxylates with higher economic value and easier recoverability. Nowadays, waste activated sludge (WAS) and food waste (FW) are the most abundant waste steams generated in European cities impacting dramatically on environment, society, and economic sectors. A novel sustainable biotechnology is here proposed to produce marketable caproic acid from mixed WAS and FW with in-situ self-formed lactate without buffering agents addition. Different mix ratios between WAS and FW, and thermal pretreatment strategies were compared by fermentation batch tests. The production of lactate as electron donor (ED), together with acetate and butyrate, and hydrogen assured high production of caproate only in presence of thermal pretreated WAS, able to reduce the potential risk of lactate accumulation and drop in pH. The findings of this study demonstrate that the initial soluble carboydrate/protein ratio significantly affected the pH of the fermentation broth in the first hours of fermentation, and that only using FW and pretreated WAS mixed using a ratio of 60/40 in terms of volatile solids, CE pathway and lactate utilization as ED were promoted obtaining the highest percentage of caproate (about 21% of the total produced carboxylic acids; 2 gCOD/L). [Display omitted] • This strategy enables biowaste conversion targeted to marketable platform. • Chain elongation to caproate with in situ generated lactate as electron donor. • Thermal pretreatment of sludge promoted the natural buffering of the system. • The 60:40 ratio of FW and pretreated WAS resulted in the highest caproic yield. [ABSTRACT FROM AUTHOR]

Sustainable development goal (SDG) 12.3 urges reducing food waste to half at retail and consumer level and minimizing the losses along food supply chains by 2030. This study contributes to achieving these targets by incorporating a secondary supply chain with primary food chain, where food waste is controlled through IoT enabled preservation mechanism at retail level, and the yet created food waste along food chain is recycled through a secondary supply chain. Food waste at retail and consumer level is collected at a collection center by incentivizing the waste returns and recycled into secondary product at recycling plant. This study develops a mathematical model, integrating primary food chain with secondary supply chain, targeting waste control and recycling, material recovery, and economic benefits. Integrating IoT technology, product's lifetime-dependent deterioration rate is controlled by adjusting preservation conditions. This technology facilitates online inventory inspections and removal of expired items. Supply chain decisions are optimized for preservation cost and cycle time. Results of numerical experiments reveal the secondary supply chain consumes all the food waste, conserves 62% of material resources, reduces preservation costs by 65.8%, and enhances profits by 49%. IoT enabled preservation strategy extends the food product's lifespan and inventory cycle time, thus, controlling the causes of food waste creation. Finally, this study offers crucial insights for decision-making in food circular supply chains. [ABSTRACT FROM AUTHOR]

Food waste is responsible for severe environmental, social, and economic issues and therefore it is imperative to prevent or at least minimize its generation. The main cause of food waste is poor demand forecasting and so it is essential to improve the accuracy of the tools tasked with these forecasts. The present work proposes four models meant to help food catering services predict food demand accurately and thus avoid overproducing or underproducing. Each model is based on a different machine learning technique. Two baseline models are also proposed to mimic how food catering services estimate future demand and to infer the added value of employing machine learning in this context. To verify the impact of the proposed models, they were tested on data from the three different canteens chosen as case studies. The results show that the models based on the random forest algorithm and the long short-term memory neural network produced the best forecasts, which would lead to a 14% to 52% reduction in the number of wasted meals. Furthermore, by basing their decisions on these forecasts, the food catering services would be able to reduce unmet demand by 3% to 16% when compared with the forecasts of the baseline models. Thus, employing machine learning to forecast future demand can be very beneficial to food catering services. These forecasts can increase the service level of food services and reduce food waste, mitigating its environmental, social, and economic consequences. • Application of machine learning algorithms to prevent food waste. • Real daily data from three catering services with a time horizon of 3 to 9 years. • Comparison between demand forecasts and real demand. • Contrast between model predictions and catering services' estimates of demand. • Reduction of food waste between 14 and 52%. [ABSTRACT FROM AUTHOR]

Currently, China's municipal solid waste (MSW) management system has been changing from mixed collection and treatment system into separated collection and treatment system. Therefore, the source separated ability of MSW, the relevant policies of MSW classification and the MSW management system are still in the stage of exploration and improvement. This study chooses to integrate waste pickers (WPs) from the informal sector into the MSW management system, so that they can conduct secondary sorting of waste as a supplement to source separation. However, the existing research does not provide a method that allows the evaluation of integrated WPs from a dynamic and long-term perspective. In this paper, the system dynamics model of MSW management is improved to provide the ability to analyze the long-term evolution of social economic benefits of integrating WPs for secondary sorting. Taking Tianjin as an example, the scenario analysis is carried out. The results show that, on the basis of the existing mixed management mode, integrating WPs for secondary sorting (80% separated rate) can reduce the waste management cost per ton by 55 yuan in 2030. Under the current situation in Tianjin where the source separation rate of food waste is 20% and the source separation rate of recyclable waste is 60%, integrating WPs can reduce the social economic cost of Tianjin's urban MSW management system by 422.45 million yuan per year from 2022 to 2030. In addition, the results show that even if the source separated rate of food and recyclable waste increases, there is still room for 20%–80% increase in wages based on giving WPs a salary higher than the national per capita disposable income in 2022. This study provides a basis for integrating WPs into Tianjin MSW management system, as well as methods and quantitative tools to integrate WPs for cities in developing countries. • Dynamics model was developed to analyze the contribution of secondary sorting of WPs. • MSW generation and disposal as well as social economic benefits in Tianjin were simulated. • WPs reduce the social economic cost 422.45 million yuan per year in Tianjin's MSW. • Even with rising labor costs, the social economic benefits of WPs are significant. [ABSTRACT FROM AUTHOR]

Upcycling agroindustry residues into new valuable products is a strategy for mitigating environmental impacts while increasing material circularity. In this study, two sizes of eggshell particles (D 90 = 7.1 μm (ESAJ) and D 90 = 16.3 μm (ESBU)) were obtained and their incorporation as fillers into biodegradable pectin/starch film was evaluated. The effect of the presence of eggshell particles (2–8 w/w%) on the structural and morphological aspects, water barrier, and mechanical, optical, and thermal properties of the biocomposites was evaluated and then the reinforced film was applied on the surface of kraft paper. The release of calcium in an acidic solution was inverse to the size and concentration of particles and the released íon may contribute to the crosslinking of pectin. The incorporation of only 2 % eggshell resulted in 42% lower solubility of the film. The eggshell-reinforced films proved to be more opaque and rigid. The addition of 6% ESAJ significantly improved the tensile strength (an increase of 32%), modulus of elasticity (an increase of 29.7%), and water vapor barrier (59% of improvement). DSC analysis suggests that the calcium from the eggshell interacts with the pectin polymeric structure, reducing the sites available for water molecules, which may have caused more mobility of the chains through the matrix. The reinforced pectin/starch film was very well adhered to the kraft paper in the application test by continuous casting, but the coated paper showed no improvement in oil and water resistance, which means that other coating processes need to be explored. • Eggshell was used as a reinforcing filler material in pectin/starch film. • Eggshell particles were well adhered to the matrix. • The eggshell powder had improved the water resistance of the pectin/starch film. • The addition of 6% eggshell had increased the film's tensile strength in 32%. [ABSTRACT FROM AUTHOR]

Food loss and waste become the sever problem in the modern society. This paper studies the carbon emissions related to different circulation forms of lychee，which is a typical perishable fruit in China. First, we construct a kinetic model of lychee by using the Arrhenius equation. And then, we propose a carbon emission measurement with the unit effective carbon emission and the comprehensive carbon emission utility by using life cycle assessment. With this measurement, we measure the rate of loss and life cycle carbon emissions of four lychee's circulation scenarios, including: cold chain, room temperature, cold chain broken at the beginning and cold chain broken at the end. The results show that with the traditional carbon emission measurement, the carbon emissions generated by the cold chain circulation scenario are the highest in total carbon emissions under the four scenarios. But using the unit effective carbon emissions measurement, the total carbon emissions under the cold chain circulation situation is 34.84 % less than those of the room temperature circulation. Under the cold chain circulation scenario, the unit effective carbon emission and comprehensive carbon emission utility are 0.38 kgCO 2 /kg and 85.33 %, respectively. Improving the rate of cold chain circulation can improve the comprehensive carbon emission utility and achieve land-saving. Comparing with the cold chain circulation rate in China in today, when it increases to 95 %, the comprehensive carbon emission utility of lychee supply chain increases to 81.65 %, and the required land is reduced by 54.84 %. • The unit effective carbon emission and the comprehensive carbon emission utility are proposed. • A kinetic model of lychee is developed to measure the loss rate of lychee. • A life-cycle carbon emissions model is developed to estimate lychee carbon emissions with different scenarios. [ABSTRACT FROM AUTHOR]

Anaerobic digestion is promising in both food waste reduction and energy upgrading. However, the intermediates in anaerobic digestion of such an oily food waste, long chain fatty acids, not only have low bioavailability but also significantly threaten operation stability. Temperature-phased anaerobic digestion is an emerging technology in recent years, expected to overcome those issues. Given significance of the first stage of the two-stage process, continuous thermophilic digestion of oily food waste was conducted, with mesophilic digestion operated in parallel as control, to determine practical operational parameters from operation performance and stability. The feeding concentration at approximately 4.50 % of volatile solids was identified to be applicative for a relatively stable operation. Due to slow β-oxidation for long chain fatty acids, hydraulic retention time for the first stage needed longer than 10 d to maintain anaerobes' survival so that they were not inhibited. In addition to the risk from inhibition, readily acidified risk still existed, and instant pH control was demonstrated to be efficient in maintaining the habitat of microbial metabolism. Compared with no viable bacteria detected under uncontrolled pH, 36.7 % live cells could still be detected under controlled pH. Overall, thermophilic digestion obviously achieved advantages in higher substance degradation and methane production with lower stability risk. The genera Methanosarcina and Methanothermobacter played a significant role, with the ratio at about 2:1. While bacterial viability was not reduced remarkably in preliminary period of inhibition, long-term operation under high lipid loading resulted in its loss. • A 55 °C–35 °C temperature-phased two-stage system was used to treat oily food waste. • Volatile solid at approximately 4.50% was determined to be appropriate. • Retention time of thermophilic stage needed at least 10 d for stable operation. • pH control was necessary to prevent pH drop and maintain methanogens' survival. • Methanosarcinales dominated acetoclastic methanogens, at above 60.0% in archaea. [ABSTRACT FROM AUTHOR]

Mapping and monitoring the process of pre-consumer food waste generation in the foodservice sector is needed to fully understand food waste, identify hotspots, and strengthen the evidence-base in this sector of the food supply chain. The purpose of this study was to validate a tool for separation and quantifying pre-consumer food waste in a quick service restaurant (QSR) setting, and to map the food waste generation process using statistical process control methodology. This included consideration of food waste categories and edible versus inedible waste. The study also explored key foodservice and menu practices which may impact food waste production. Food waste audits were undertaken in two food outlets (FOs) in an Australian university campus over a two-week operating period for each outlet using a direct weighing method. Foodservice operation and menu practices occurring in the outlets during the audit period were also recorded. These observations validated practices reported by the owner-manager of the FOs during interviews. The amount of waste collected separately from each outlet was analysed using statistical process control methodology. While each FO was treated as a separate case study, the same methodology was applied to each, allowing some comparison between outlets. Despite differences in foodservice style and menus, the average daily pre-consumer food waste produced from all food waste categories was approximately 25 kg for both outlets, with about 60% from inedible waste. This equated to approximately 5.5–6.1 kg of pre-consumer waste per full-time-equivalent employee (FTE) per day. Used coffee grounds was the largest single contributor of total pre-consumer waste for both FOs. Both FOs demonstrated compliance with Australian best practice in foodservice operations and menu design. The study concludes that the method used to separate pre-consumer food waste into different categories and quantify this waste was a practical tool for these QSRs and allowed researchers to validate both the separation process and the amount of waste collected. Analysis of data using statistical process control allowed differentiation between common and special cause of variations. These findings can help inform processes which generate food waste in these types of foodservice settings and assist with the development of food waste reduction initiatives. • Separating food waste types and direct weighing is a valid tool for QSR audits. • Statistical process control can demonstrate volatility in food waste production. • Pre-consumer food waste audits can identify food waste hotspots in QSRs. • More than 60% of pre-consumer food waste generated by QSRs was inedible waste. • Used (spent) coffee grounds were the major contributor to food waste from the QSRs. [ABSTRACT FROM AUTHOR]

Emission of volatile organic compounds (VOCs) from food waste is a key trouble for surrounding residents. Herein, the VOC emission patterns from headspace (gaseous) and produced leachate (aqueous) during decomposition of cooked milk cabbage, tilapia fish, and their mixture (Mix) were investigated in self-made reactors. The average amount of gaseous VOCs from fish (2888.7 mg/kg dry matter (DM)) was higher than Mix (2152.9 mg/kg DM) and cabbage (374.2 mg/kg DM). The dominant VOCs were volatile organic sulfur compounds (VOSCs) and oxygenated VOCs, accounting for 65.8 and 32.5 %, 71.8 and 25.2 %, 39.0 and 36.7 % of total VOC yields in fish, Mix, and cabbage, respectively. From leachate, average leaching fluxes of VOCs followed the order of: Mix (2487.9 μg/(L kg) DM) > fish (2374.7 μg/(L kg) DM) > cabbage (368.7 μg/(L kg) DM). VOSCs were also the major VOCs from leachate, accounting for 87.9, 98.6, and 98.5 % of total VOCs in leachate, respectively. Lactobacillus and Weissella were the dominant genera in cabbage, while Bacteroides were dominant in fish and Mix. Physicochemical factors were significantly related to bacterial composition shifts over time. Furthermore, Lysinibacillus and Vibro were positively correlated with gaseous dimethyl disulfide, while Lactobacillus , Weissella , Savagea, Ignatzschineria , Acinetobacter , and Pseudomonas showed strong relationship with dominant gaseous and aqueous VOCs. These findings provide significant references for understanding distribution and controlling of VOCs released during cooked food waste fermentation. [Display omitted] • VOCs in air released from cooked fish were 7.7 times higher than that of cabbage. • Sulfur compounds were dominant VOCs emitted from wastes and produced leachates. • VOCs tend to volatilize from food waste to air. • Cooked fish and mixture have similar bacteria community, but different from cabbage. • Dominant bacteria were significantly correlated with VOCs in air and leachate. [ABSTRACT FROM AUTHOR]

To address the pressing need for reducing carbon emissions linked to fossil fuels, there is an urgent requirement to explore cleaner fuel options as substitutes for traditional fossil energy sources. This study introduces an innovative experimental comparative method where corn stover (CS) is used as an external additive to create three types of samples: mixed feedstocks, mixed-hydrochar (MHC), and co-hydrochar (CHC), in conjunction with food waste (FW). By comparing CHC with MHC, the influence of co-hydrothermal carbonization (co-HTC) synergy on their physicochemical properties and combustion performance has been confirmed. The research results indicate that CHC demonstrates superior attributes in terms of physical and chemical properties, energy output, and combustion behavior. Furthermore, dynamic parameters were determined using the Flynn-Wall-Ozawa (FWO) and Friedman methods. According to the FWO and Friedman calculations, the average activation energy for CHC is 128.5 kJ/mol and 114.3 kJ/mol, which is lower than that of mixed feedstocks and MHC. These research findings suggest that utilizing FW and biomass for the synthesis of CHC results in a lower activation energy, making it more suitable for energy applications. In summary, CHC derived from FW and biomass presents a promising approach for renewable energy production. [Display omitted] • Co-hydrochar exhibits greater energy output and carbon preservation. • Both mixed-hydrochar and co-hydrochar share resemblances with the properties of lignite. • Co-hydrochar displays an elevated level of aromatic ring formation. • Kinetic models support co-hydrochar's superior combustion due to its lower activation energy. [ABSTRACT FROM AUTHOR]

The healthcare sector greatly impacts the environment through energy, transport, product use, disposal and food service. This requires significant interventions to reduce energy consumption and waste generation and increase customer satisfaction simultaneously. Considering the need to investigate food waste amounts and energy consumption in hospitals, the present research has a triple goal. First, it evaluates energy consumption and efficiency by comparing cook-hold and cook-chill catering. Second, it estimates the customer satisfaction of the served meals and third, it assesses the food waste quantities at lunch and dinner among hospital patients. Specifically, the research combines (a) the evaluation of the energy consumption, based on primary data collected in a cooking center with a production capacity of 1590 meals per production cycle; (b) the investigation of the consumers' behavior among 984 patients located in nine different hospital units in Southern Italy; (c) the measurement of food waste based on questionnaire-survey data. Results highlight the reduction in diesel consumption (– 42%) and in electricity consumption (– 93%), as well as the reduction in food waste (– 85%) when comparing cook-hold with cook-chill catering. This research illustrates a guideline in the field of efficient catering. It helps identify sustainable pathways and interventions toward energy efficiency, customer satisfaction, and food waste minimization for policymakers, healthcare professionals, catering companies or patients. [ABSTRACT FROM AUTHOR]

Halving food loss and waste is the target of the UN's Sustainability Development Goal 12.3, and household food waste constitutes a substantial part of global food waste. Effective interventions that decrease household food waste are urgently needed, and these could target various underlying behaviours such as planning, storing, preparing and consuming. There is a lack of studies that develop interventions based on theory and that compare different intervention options. Moreover, in testing the effectiveness of such interventions, possible influences caused by the measurement method need to be assessed. The current study explores two interventions, based on the Motivation-Opportunity-Ability framework, to test if combining a tool package (containing various waste-reducing tools such as a measuring cup, stickers, leaflets, recipes) with a motivational message based on social norms is more effective than the tool package alone. Additionally, it examines the effects of using a self-reported survey measurement for household food waste, to ensure that results are not caused by increased consumer awareness of food waste due to measurement alone. Findings show that the tool package significantly improves waste-preventing behaviours, and decreases self-reported food waste by 39.2% (experiment 1) and 23.0% (experiment 2). Effects on waste-preventing behaviours are stronger when social norm elements are added in the intervention. Results of the second experiment indicate that effects of self-reported measurement are minimal, which provides initial support for the use of self-reported food waste measurement in intervention testing albeit that underreporting remains an issue and more research is needed. • A tool kit for food management (measuring cup, stickers, etc) diminished food waste. • Effects on waste-preventing behaviours were stronger with added social norm messages. • In this study, effects of using self-reported food measurement appeared minimal. [ABSTRACT FROM AUTHOR]

Households are responsible for more than 50% of food waste in the European Union. Although attention on household food waste has been growing, progress in reducing it has been slow. It is therefore important to understand what influences household food waste to provide guidelines for communication strategies that promote food waste reductions. This study proposes a new conceptual model linking the amount of food waste with its causes, guiding effective communication strategies. To validate the conceptual model, data was collected through an online survey with 376 valid responses. The results reveal that motivations and behaviors have moderate correlations with the amount of food wasted. These two variables, along with age, gender and number of people and children in the household were used to form clusters, which represent four types of urban consumers in relation to motivations and behaviors towards food waste generation (impulsive waster (17%), planner (26%), young waster (27%) and fan of leftovers (30%)). Driven by the results, guidance for tailored communication strategies for each cluster is proposed. Those strategies foster not only promoting anti-food waste behaviors through tips related to shopping, storage, and cooking, but also emphasizing the social inequalities stemming from food insecurity and the risks associated with poverty. Policymakers, researchers, and practitioners should incentivize shopping and planning strategies that mitigate food waste, tailed to young and impulsive wasters. The conceptual model can be used in other countries after adaptations to reflect cultural differences. • A conceptual model linking the amount of food waste with its causes is created. • Food waste can be influenced by information, knowledge, motivations and behaviors. • Cluster analysis is a useful tool to propose tailored communication strategies. • Strategies to reduce food waste should focus on promoting anti-food waste behaviors. • Highlighting social inequalities related to poverty may help reduce food waste. [ABSTRACT FROM AUTHOR]

Eco-friendly delivery carrier of trace metals is very significant to appropriate metal supplementation to improve metal bioavailability and prevent metal precipitation in anaerobic digesters. A novel encapsulated form of dry water (DW) additive was synthesized by the high-speed mixing of nickel ions solution with hydrophobic silica nanoparticles and was characterized using scanning electron microscope (SEM), nuclear magnetic resonance (NMR) and particle size analyzer. Nickel (Ni) was chosen as a model trace element. The encapsulated structure of DW additive and the feasibility of controlled release of Ni ions from DW additive in pure water and anaerobic digesters were verified. The optimal mixing speed for the highest methane yield of digesters with DW additive was determined as 800–1000 rpm. By varying stirring speed, controlled release of trace metal element (Ni) into digester was easily achieved during anaerobic digestion of food waste. The results showed that nickel ions delivery via DW additive significantly enhanced the metal bioavailability by 18.9–42.6% and process stability during 59 days of operation, resulting in an increase of 11.6–31.8% in methane yields compared to the controls. Pyrosequencing analysis indicated that bacterial communities were dominated by phyla Firmicutes , Bacteroidetes , Proteobacteria , Chloroflexi and Spirochaetes while methanogenic genus Methanolinea , Methanoculleus , Methanothrix , Methanomassiliicoccus and Methanospirillum were more abundant in archaea communities. Further, phyla Bacteroidetes , Proteobacteria and Methanoculleus were selectively enriched by the DW additive. Results indicated that it was feasible to apply the method of DW additive supplementation to enhance anaerobic digestion of food waste for biogas production by improving metal bioavailability. Image 100004 • An encapsulated dry water (DW) additive was developed for trace element delivery. • Shear stress-based controlled release of Ni2+ was achieved by varying stirring rate. • Bioavailability of nickel ions was enhanced by 19–43% via DW additive for delivery. • Methane yield increased by 12–32% due to DW additive compared to the controls. • Phyla Bacteroidetes , Proteobacteria and Methanoculleus were enriched by DW additive. [ABSTRACT FROM AUTHOR]

Sustainable approaches for the anaerobic digestion treatment of food waste to minimize environmental challenges and recover energy are some economic goals receiving global attention. Meeting global bio-energy demand from food waste and associated waste residues requires exploring alternative optimization routes. Pyrolysis process for the treatment and recycling of difficult biodegradable fractions in food waste processing facility, and the subsequent utilization of real syngas in anaerobic digestion as a food waste treatment were investigated to evaluate their effects on biofuel production via bio-methanation. Different proportions of syngas that are transformed into methane show that the carbon monoxide content in the reactors (G21, G23, G61, and G63) was completely degraded on 195, 195, 95, and 145 h. The higher hydrogen concentration in the simulated syngas expedites the carbon monoxide degradation rate. Application of two-stage pyrolysis to difficult biodegradable fractions treatment generated real syngas (Hydrogen 60: Carbon monoxide 20 vol%) for improved bio-methanation (100% methane) compared to the blank. The simulated syngas from the anaerobic digestion treatment of food waste generated methane (75–80%) than the control (45%). Results from both the simulated and real syngas show that high volume percent of hydrogen in the syngas positively influenced the degradation and transformation of carbon monoxide and promoted a higher rate of bio-methanation. Further study showed that pH values in the range 7.21–7.78, and low concentrations of volatile fatty acids and ammonia nitrogen indicated no toxicity from syngas bio-methanation with anaerobic digestion. This route is beneficial for enhancing the value of resources recovered from difficult biodegradable fractions pyrolysis, achieving a higher bio-methanation rate, and improving sludge stabilization with anaerobic digestion treatment of food waste. • Difficult biodegradable fractions were pyrolyzed to produce hydrogen rich syngas. • Increase in carbon monoxide concentrations prolonged its degradation rate. • Sufficient hydrogen (60 vol%) in real syngas has no inhibitory effect. • Real syngas bio-methanation generates almost 100% methane. • Bio-methanation performance and sludge stabilization was enhanced. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate respondent's attitudes and reasons related to food waste and to estimate the weekly amounts of discarded food waste and food packaging waste in Serbia. A total of 494 citizens of Belgrade, capital of Serbia, were interviewed. They had the option to rate their degree of agreement related to 28 food waste statements as well as to recall the quantities of discarded food waste and food packaging waste. In parallel, a Monte Carlo simulation was performed to estimate CO 2 emission of food waste and food packaging waste. Our research revealed that citizens of Serbia feel guilty and have a bad conscience when they waste food. The main two reasons for throwing away food comes from food with expired dates and observed rotten smells and tastes. Bread and bakery products are types of food mostly discarded in Serbia while plastic bags are types of food packaging mostly discarded. Regarding food waste quantities, it is estimated that households dispose around 1.54 kg of food waste every week and about 65 different pieces of food packaging. The global warming impact of food waste and food packaging waste was quantified around 3.46 kg CO 2 e/household a week and 0.16 kg CO 2 e/household a week, respectively. Learning from this and previous studies, we believe our research contributes to the overall perspective of food waste in Europe as its based on collecting data on food waste and food packaging waste joint with comparing statements of interviewees on food waste. • A total of 494 citizens of Serbia were interviewed regarding food waste. • Citizens of Serbia feel guilty and have a bad conscience when they waste food. • Households discard 1.5 kg of food waste and 65 different pieces of food packaging a week. • Global warming potential of food waste is 3.46 kg CO 2 e/household a week. • Global warming potential of food packaging waste is 0.16 kg CO 2 e/household a week. [ABSTRACT FROM AUTHOR]