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Every year, a great production of food waste is generated. These wastes have a negative effect on economic and environmental aspects even though they include a considerable quantity of phenolic compounds. Thus, in recent years, there has been much research about the recovery of phenolic compounds from food waste. Emerging technologies such as ultrasound, microwave, high hydrostatic pressure, supercritical fluid, pressurized liquid, and pulsed electric field have been accepted as alternative extraction techniques to conventional extraction techniques because of increasing extraction yield and reducing hazardous chemicals, time, and energy. This comprehensive review aims to analyze the ongoing research on applying emerging techniques in the valorization of food waste based on recent research. Also, this gives general extraction mechanisms of these techniques and compares them with each other. The findings discussed through this comprehensive review may be a valuable tool for industry to integrate economical and efficient extraction methods, converting food waste to a high-added value functional product. [ABSTRACT FROM AUTHOR]

Abstract Background Recycling nutrients and organic matter available as waste in urban areas may close nutrient gaps and improve soil quality, but the concentrations of potentially toxic elements (PTEs) are commonly higher than in mineral fertilisers. How quickly may the limits for soil quality be exceeded, and for which elements, if such materials are applied intensively? For a rough answer to this question, we used soil data from ten case farms near Oslo and Bergen (Norway) to estimate how PTE concentrations increased when the demand for nitrogen (N), phosphorus (P) and potassium (K) in a theoretical carrot crop produced every year was covered by compost or digestate from source-separated food waste, or composted garden waste, compared with manure from horses and poultry which are often kept in peri-urban areas. Results With the intensive fertilisation assumed here, the Norwegian soil quality limits for PTEs were reached within 20–85 years, and faster for soil with more organic matter since regulatory limits set by weight discriminate soils with low bulk density. The limits were reached first for Cu and Zn, which are both essential micronutrients for crop plants. The concentrations of macronutrients in the urban waste-based fertilisers were not well balanced. Rates covering the K demand would lead to high surpluses of P and N. In peri-urban vegetable growing, high applications of compost are not unusual, but more balanced fertilisation is required. Conclusions The Norwegian regulations for PTEs in organic soil amendments and agricultural soil are stricter than in the EU, and do not support recycling of organic matter and nutrients from urban waste. Many materials which can only be applied with restricted amounts to Norwegian agricultural soil, may be applied according to crop demand in the EU. Growers utilising urban waste-based fertilisers intensively should monitor the soil regularly, including PTE analyses. Soil sampling should occur on fixed sampling points to reveal changes in concentrations over time. Norwegian authorities should consider a revision of the organic fertiliser regulation to support recycling of valuable organic materials. There is a need for more data on the PTE concentrations in agricultural soil and organic fertiliser materials.

Background: Recycling nutrients and organic matter available as waste in urban areas may close nutrient gaps and improve soil quality, but the concentrations of potentially toxic elements (PTEs) are commonly higher than in mineral fertilisers. How quickly may the limits for soil quality be exceeded, and for which elements, if such materials are applied intensively? For a rough answer to this question, we used soil data from ten case farms near Oslo and Bergen (Norway) to estimate how PTE concentrations increased when the demand for nitrogen (N), phosphorus (P) and potassium (K) in a theoretical carrot crop produced every year was covered by compost or digestate from source-separated food waste, or composted garden waste, compared with manure from horses and poultry which are often kept in peri-urban areas. Results: With the intensive fertilisation assumed here, the Norwegian soil quality limits for PTEs were reached within 20–85 years, and faster for soil with more organic matter since regulatory limits set by weight discriminate soils with low bulk density. The limits were reached first for Cu and Zn, which are both essential micronutrients for crop plants. The concentrations of macronutrients in the urban waste-based fertilisers were not well balanced. Rates covering the K demand would lead to high surpluses of P and N. In peri-urban vegetable growing, high applications of compost are not unusual, but more balanced fertilisation is required. Conclusions: The Norwegian regulations for PTEs in organic soil amendments and agricultural soil are stricter than in the EU, and do not support recycling of organic matter and nutrients from urban waste. Many materials which can only be applied with restricted amounts to Norwegian agricultural soil, may be applied according to crop demand in the EU. Growers utilising urban waste-based fertilisers intensively should monitor the soil regularly, including PTE analyses. Soil sampling should occur on fixed sampling points to reveal changes in concentrations over time. Norwegian authorities should consider a revision of the organic fertiliser regulation to support recycling of valuable organic materials. There is a need for more data on the PTE concentrations in agricultural soil and organic fertiliser materials. [ABSTRACT FROM AUTHOR]

The purpose of this study was to explore effects of different types of food wastes on the growth and body composition of Hermetia illucens L. three treatment groups were set, namely the rice group, the mixture group (rice and offal), and the offal group. A total of 7 200 larvae aged 7 days (initial weight 7.84 mg, body length 5.87 mm) were selected and randomly assigned to 9 boxes of uniform size, 800 larvae per box, with three duplicates for each treatment group. During the experiment, the breeding room temperature was 28 ℃ and the relative humidity was 65%. The growth indicators of larvae were measured every 3 days, and the activity and death of larvae were recorded. When the pupation rate of offal group was 5%, the test was finished, and the contents of conventional components and fatty acids in the objects were examined. The results showed that Hermetia illucens L. had the best growth performance and development in the mixture group, and the growth indexes of this group were significantly higher than those of the other 2 groups (P<0.05). In the offal group, the body were rich in crude protein and linoleic acid, while its growth rate and pupation rate were significantly lower than those of the other 2 groups (P<0.05). Hermetia illucens L. in rice group had a higher tendency of intaking lauric acid (C12∶ 0), while the Omega-3 fatty acids contained in the body of the mixutre group were significantly higher than that of the offal group. Therefore, food waste, such as offal which contains high animal protein, produces better performance when matched with rice. [ABSTRACT FROM AUTHOR]

The mycelium makes up the thallus, or undifferentiated body of a fungus such as brackets, mushrooms, puffballs, rhizomorphs, sclerotia, stinkhorns, toadstools, and truffles. Mushrooms are fleshy fungi and there are edible or poisonous types. The edible mushrooms are consumed as food in different part of the world and are recognized for their ability to convert waste products into a protein-rich-food. In this study, different agro-allied wastes materials were used as substrates to grow Pleurotus ostreatus (White Oyster). The substrates include top forest humus, sawdust, ground nut shell, corn cobs, raphia inflorescence, cassava peel and fermented cassava chaff. Sawdust had the highest single mycelia yield of White Oyster producing 491.67±12.583g with Biological Efficiency of 49.167±1.2583% followed by top forest humus 426.67±20.8117g with Biological Efficiency of 42.667±2.081%. Ground nut shell, raphia inflorescence, cassava peel and fermented cassava chaff demonstrated low mycelia yield of mushroom with Biological Efficiency of 34.00±0.5%, 12.00±0.50%, 15.10±0.36% and 16.167±0.47% respectively. A 1:1 combination of corn cobs and sawdust has the highest yield of 495±10.00g. The study showed sawdust is the most suitable for oyster mushroom cultivation and should be encouraged to be employed for commercial production of mushrooms. Furthermore, the combination of Sawdust and top forest humus, sawdust and corn cobs substrates demonstrated high mycelia yield of mushroom. [ABSTRACT FROM AUTHOR]

The compound 5-(hydroxymethyl)furfural (HMF) has emerged as a versatile intermediate with the ability to undergo conversion into both fuel and a variety of platform chemicals. Lignocellulosic biomass, such as hazelnut shells and tea processing residues, was employed in this study for HMF production through two distinct methods. In the first method, cellulose from biomass was converted to sugars using a 4% acid solution, followed by catalytic conversion with NaCl/CrCl3.6H2O. After a 1-h reaction at 131 °C in a high-pressure system, HMF was obtained from tea processing waste and hazelnut shells with yields of 8.6% (82.3 mg/g) and 6.7% (66.7 mg/g), respectively. The second method involved LiCl/NaCl-doped N,N-dimethylacetamide (DMA) as an ionic solvent system for HMF production. After a 2-h reaction at 131 °C in the DMA-NaCl/[EMIM]Cl ionic solvent system, HMF was obtained from tea processing waste and hazelnut shell celluloses with yields of 5.7% (57.5 mg/g) and 3.1% (31.3 mg/g), respectively. This study contributes to the economic conversion of various food wastes into valuable chemicals, highlighting the potential of lignocellulosic biomass in sustainable chemical production.

The compound 5-(hydroxymethyl)furfural (HMF) has emerged as a versatile intermediate with the ability to undergo conversion into both fuel and a variety of platform chemicals. Lignocellulosic biomass, such as hazelnut shells and tea processing residues, was employed in this study for HMF production through two distinct methods. In the first method, cellulose from biomass was converted to sugars using a 4% acid solution, followed by catalytic conversion with NaCl/CrCl3.6H2O. After a 1-h reaction at 131 °C in a high-pressure system, HMF was obtained from tea processing waste and hazelnut shells with yields of 8.6% (82.3 mg/g) and 6.7% (66.7 mg/g), respectively. The second method involved LiCl/NaCldoped N,N-dimethylacetamide (DMA) as an ionic solvent system for HMF production. After a 2-h reaction at 131 °C in the DMA-NaCl/[EMIM]Cl ionic solvent system, HMF was obtained from tea processing waste and hazelnut shell celluloses with yields of 5.7% (57.5 mg/g) and 3.1% (31.3 mg/g), respectively. This study contributes to the economic conversion of various food wastes into valuable chemicals, highlighting the potential of lignocellulosic biomass in sustainable chemical production. [ABSTRACT FROM AUTHOR]

The overuse of chemical fertilizers degrades the soil ecosystem and restricts the natural development of plants. Various byproducts are produced throughout the production and consumption of coffee within the coffee industry, and they are significant in terms of environmental waste. Spent coffee grounds (SCGs) contains various bioactive compounds that have demonstrated potential applications in various fields. These compounds can enhance soil quality by improving its physicochemical properties and biological fertility, ultimately leading to improved plant growth and reducing food waste and contamination at the same time. This current study examined the impact of chemical fertilizer, vermicompost, SCGs with percentage fertilizer (SCGPF), and SCGs on the top dressing fertilizer (SCGTDF) on red radish (Raphanus sativus) growth and soil quality. This greenhouse experiment tested various concentrations of SCGPF (5%, 10%, 25%, and 50%) and different doses of SCGTDF (0.5 g, 1 g, and 2.5 g). The results showed that the 0.5 g SCGTDF treatment yielded the highest mean plant length (18.47 cm) and fresh weight (27.54 g), while the vermicompost at a 50% concentration produced the highest mean leaf surface area (58.32 cm2). These findings suggest the potential of SCGs as a sustainable fertilizer alternative, contributing to improved plant growth and soil quality, thus supporting sustainable agricultural practices and a circular economy. [ABSTRACT FROM AUTHOR]

The current study investigated the methane generation potential from the anaerobic bio-digestion of fruits and vegetables wastes (FVW) generated in a food supply center in Brazil. This study used the ensiling process as a pre-treatment for this lignocellulosic biomass aiming to improve the methane yield. FVW were mixed in the same proportion (0.2 g on a volatile solid basis per residue) and ensiled at room temperature (≈25 °C) for 30 and 55 days (samples Ensil-30 and Ensil-55). The ensiled and untreated waste samples were inoculated with industrial granular sludge and incubated at 37 °C (mesophilic conditions) until there was no more significant biogas generation. The experimental data were fitted to the First-order, Cone, and Modified Gompertz kinetic models. The methane yield of the ensiled samples was ≈21% higher than the methane yield of the untreated sample. Considering the ensiled samples, the methane generation was statistically the same (52.0 and 51.3 NmL/gvs for samples Ensil-30 and Ensil-55, respectively), that is, duplication of the storage period failed to increase the methane volume. Although the results indicated that the ensiling of FVW could be a viable strategy to improve the biodegradability of the lignocellulosic biomass and promote its valorization as an energy source, a preselection of the agricultural residues that will feed the biodigesters is suggested. Considering the process conditions and the residues used, the substrate characteristics were shown to carry out a key role in the bio-digestion processes and consequently in methane generation. [ABSTRACT FROM AUTHOR]

The demand for energy resources is constantly increasing. That means need more fossil fuels to provide them. People consume a lot of food and this produces many wastes. Microbial fuel cells (MFCs) represent a new technological method with the potential to generate bioelectricity by the action of electrogenic bacteria on food wastes while reducing the amount of food wastes. This study investigated the possibility of usage of real restaurant wastewater as a fuel (substrate) for microbial fuel cell and its effects on the bacterial consortium attached to the electrodes. Mathematical (R2 > 0.96) and statistical (R2 > 0.99) models were conducted for the MFC performance focusing on the polarization curves. The study demonstrated that the highest COD removal (88.69%) in the semi-batch mode and (99.64%) in continuous mode, and power density (10.9 mW/m2) and (56.8 mW/m2) in semi-batch and continuous mode, respectively. The Bacterial diagnosis for anodophilic biofilm showed important differences in distribution and density of a heavy growth consortium after operation. This research offers restaurants an eco-friendly solution. This is because it demonstrates the benefits of using their own wastewater for power generation, reducing costs and saving the environment. [ABSTRACT FROM AUTHOR]

The mycelium makes up the thallus, or undifferentiated body of a fungus such as brackets, mushrooms, puffballs, rhizomorphs, sclerotia, stinkhorns, toadstools, and truffles. Mushrooms are fleshy fungi and there are edible or poisonous types. The edible mushrooms are consumed as food in different part of the world and are recognized for their ability to convert waste products into a protein-rich-food. In this study, different agro-allied wastes materials were used as substrates to grow Pleurotus ostreatus (White Oyster). The substrates include top forest humus, sawdust, ground nut shell, corn cobs, raphia inflorescence, cassava peel and fermented cassava chaff. Sawdust had the highest single mycelia yield of White Oyster producing 491.67±12.583g with Biological Efficiency of 49.167±1.2583% followed by top forest humus 426.67±20.8117g with Biological Efficiency of 42.667±2.081%. Ground nut shell, raphia inflorescence, cassava peel and fermented cassava chaff demonstrated low mycelia yield of mushroom with Biological Efficiency of 34.00±0.5%, 12.00±0.50%, 15.10±0.36% and 16.167±0.47% respectively. A 1:1 combination of corn cobs and sawdust has the highest yield of 495±10.00g. The study showed sawdust is the most suitable for oyster mushroom cultivation and should be encouraged to be employed for commercial production of mushrooms. Furthermore, the combination of Sawdust and top forest humus, sawdust and corn cobs substrates demonstrated high mycelia yield of mushroom.

Natural gas, coal, and oil account for over 84 % of the world’s energy demand. Greenhouse gases, including carbon dioxide, methane, and oxides of nitrogen and sulphur, are released during the combustion of fossil fuels, leading to substantial climate changes and environmental damage. Therefore, harnessing energy from alternative sustainable resources without the emission of harmful waste products is vital for the ecosystem’s health. By 2050, global food waste production will reach 3.4 billion metric tons. Although widely recognized as a substantial energy resource, its value is underutilized throughout sub-Saharan Africa (SSA). Therefore, understanding and exploiting the potential value of food waste as a biofuel can result in net-zero emissions, reducing significant environmental pollution while conserving natural resources. Furthermore, this paper reviews how effective management of food waste will have the potential to contribute to the development of waste-to-energy resources in SSA countries, as well as help improve global ecosystems.

The development of eco-friendly polymer composites with multifunctional properties aligns with the goals of the circular economy agenda, which aims to minimize waste and promote the sustainable use of resources by closing the loop of product life cycles. Eco-friendly polymer composites play a crucial role in achieving these objectives. The present work focuses on the preparation of fully biobased blends obtained by melt mixing a bio-polyester, poly(butylene succinate- co -adipate) (PBSA), with orange peels up to 20 wt%, to yield active polymer composites. Orange peels, employed here as natural filler, are largely available from food wastes, they are rich in phenolic compounds and possess antioxidant activity as shown by the experimental tests carried out. The thermal stability of the formulated composites is almost unchanged by the filler addition, showing only a slight decrease of the crystallization temperatures and crystalline fraction within the composites. The mechanical properties of the compounds evidence an increase in the elastic modulus together with a decrease in the tensile strength, while the elongation at break remains almost constant. The incorporation of the natural filler enabled the integration of antioxidant and antibacterial properties, which were absent in the original pristine polymer. • PBSA containing up to 20 wt% of orange peels have good antioxidant and antibacterial properties. • Biocomposites formulated with orange peels are found to retain good mechanical properties in terms of elongation at break. • The thermoplastic material produced can be used in the packaging industry or in the organic or integrated farming sector application. [ABSTRACT FROM AUTHOR]

This study investigated the effect of using some food industry wastes such as broken rice (BR), broken pasta (BP), and broken faba bean (BFB) on the physicochemical, textural, microstructure, and sensory properties of processed cheese spread (PCS). The BR, BP, and BFB were converted into flour (BRF, BPF, and BFBF, respectively) and added to processed cheese formulas at levels of 5, 10 and 15%. The results showed an increase in the values of total solids, fat, protein, ash, carbohydrates, fiber, and acidity in the processed cheese by adding the obtained flours, and these values were increased with increasing the addition level. The PCS containing BFBF had the highest values of protein, ash, and fiber compared to all the other treatments. The texture parameters (hardness, adhesiveness, cohesiveness, gumminess and chewiness) were increased by increasing the rate of addition of BRF, BPF, and BFBF compared to the control treatment. Also, it was found that the BRF and BPF improved the microstructure properties of the PCS samples. The sensory evaluation results showed that the highest degree of acceptance was with samples made using BPF at levels of 10% and 15%., while with BRF and BFBF the most acceptable values were observed with an addition level of 10% compared to the control. [ABSTRACT FROM AUTHOR]

Background: Food and agricultural wastes are produced in huge amounts yearly, putting extra effort into their removal or valorization. One of these wastes is the zucchini heads (ZH) which, in this study, was used as a source to isolate peroxidase using three-phase portioning (TPP). Results: Different parameters of TPP were optimized to ensure obtaining the maximal activity recovery and purity of the enzyme. The purity of the isolated enzyme was performed using the protein homogeneity module of dynamic light scattering. This was followed by the determination of the optimal pH and temperature of the isolated ZH peroxidase. It was found that sodium citrate at a concentration of 15%, pH 8, 1-butanol as the upper alcoholic phase, and an alcohol/crude extract ratio of 0.75:1 were the best conditions for ZH peroxidase isolation. The obtained activity recovery and purification fold were 159% and 10.05, respectively. The isolated ZH peroxidase displayed a high purity as emphasized via dynamic light scattering. The optimum pH and temperature were 8 and 25°C. Conclusions: The present study was the first to isolate and purify peroxidase from ZH using TPP in one step.How to cite: Al-Madhagi H, Yazbik V, Abdelwahed W. One-step isolation and purification of peroxidase from zucchini heads. Electron J Biotechnol 2023. https://doi.org/10.1016/j.ejbt.2023.08.002.

In this paper the oven drying process was applied on olive pomace to obtain material useful for food and cosmetic applications. Two-phase olive oil mill, WOP (Wet Olive Pomace) and three-phase olive oil mill, SOP (Solid Olive Pomace) obtained in Veneto region were considered. Materials were dried in a thermostatic oven in three different conditions, 50 ° for 48 h, 75 °C for 24 h and 100 °C for 12 h. Dried pomaces were analysed for their content in fibres, sugars, fatty acids, total protein and minerals showing their nutritional value. Furthermore, determination of polyphenols, secoiridoids, triterpene acids, tocopherols were obtained. The dried samples presented 17–21% of lipids, being oleic acid the 50% of total. Protein content ranged from 5–10% while total dietary fiber ranged from 45–66%. Antioxidant and enzyme inhibition assays were performed. Dried olive pomaces presented similar activities compared to OL on the ability to inhibit enzymes. WOP exhibited stronger antioxidant abilities than SOP, but still less efficient than OL. Significant inhibitory activities on tyrosinase suggest potential usefulness in cosmetic applications. In conclusion our data shown that the dried olive pomace thanks to their composition and properties can be developed with further studies for feed, food, nutraceutical and cosmetic applications. [Display omitted] • Different oven drying process for olive pomace was performed. • Dried samples were examined for chemical profiles and biological activities. • Antioxidant and enzyme inhibitory effects were determined. • Wet olive pomace was found to be the strongest for antioxidant properties. • Olive pomace can be useful for preparing novel functional applications. [ABSTRACT FROM AUTHOR]

The last decade has witnessed a steady transition from the linear economic model to a restorative system that drives substantial and lasting improvements of the global resource productivity. In this scenario, the blue economy encompasses all industries and sectors related to oceans, seas and coasts. The blue economy model promotes a series of actions towards sustainability, which include minimization of food waste production through the re-utilization of the marine by-products. Within the food chain, the large amount of waste generated by the tuna fishery industry represents a rich pool of bioactive molecules, including polyunsaturated fatty acids, vitamins, amino acids (AAs) and peptides. Specifically, small- and medium-size peptides are emerging as a more convenient alternative to conventional antibiotic agents, against a variety of bacteria, fungi and viruses. This study focused on the retrieval of the protein fractions contained in the discards from the yellowfin tuna (Thunnus albacares) cannery industry. Protein hydrolysates obtained by enzymatic digestion were characterized by a peptidomic strategy based on reversed-phase ultra-high–pressure liquid chromatography followed by quadrupole-time-of-flight tandem mass spectrometry detection (data dependent analysis). A total of 196 AAs sequences were identified by matching MASCOT database, and their activity was predicted by support vector machine–based computational tools. As a result, significant antimicrobial scores were obtained for 22% of the identified peptides. Specifically, antibacterial, antifungal and antiviral properties were predicted based on compositional features (pseudo AA compositions and normalized AA compositions) and physicochemical properties (isoelectric point, hydrophobicity and net-charge). [ABSTRACT FROM AUTHOR]

The overuse of chemical fertilizers degrades the soil ecosystem and restricts the natural development of plants. Various byproducts are produced throughout the production and consumption of coffee within the coffee industry, and they are significant in terms of environmental waste. Spent coffee grounds (SCGs) contains various bioactive compounds that have demonstrated potential applications in various fields. These compounds can enhance soil quality by improving its physicochemical properties and biological fertility, ultimately leading to improved plant growth and reducing food waste and contamination at the same time. This current study examined the impact of chemical fertilizer, vermicompost, SCGs with percentage fertilizer (SCGPF), and SCGs on the top dressing fertilizer (SCGTDF) on red radish (Raphanus sativus) growth and soil quality. This greenhouse experiment tested various concentrations of SCGPF (5%, 10%, 25%, and 50%) and different doses of SCGTDF (0.5 g, 1 g, and 2.5 g). The results showed that the 0.5 g SCGTDF treatment yielded the highest mean plant length (18.47 cm) and fresh weight (27.54 g), while the vermicompost at a 50% concentration produced the highest mean leaf surface area (58.32 cm2). These findings suggest the potential of SCGs as a sustainable fertilizer alternative, contributing to improved plant growth and soil quality, thus supporting sustainable agricultural practices and a circular economy.

Food wastes can be hydrolyzed into soluble microbial substrates, contributing to sustainability. Halomonas spp.-based Next Generation Industrial Biotechnology (NGIB) allows open, unsterile fermentation, eliminating the need for sterilization to avoid the Maillard reaction that negatively affects cell growth. This is especially important for food waste hydrolysates, which have a high nutrient content but are unstable due to batch, sources, or storage conditions. These make them unsuitable for polyhydroxyalkanoate (PHA) production, which usually requires limitation on either nitrogen, phosphorous, or sulfur. In this study, H. bluephagenesis was constructed by overexpressing the PHA synthesis operon phaCAB Cn (cloned from Cupriavidus necator) controlled by the essential gene ompW (encoding outer membrane protein W) promoter and the constitutive porin promoter that are continuously expressed at high levels throughout the cell growth process, allowing poly(3-hydroxybutyrate) (PHB) production to proceed in nutrient-rich (also nitrogen-rich) food waste hydrolysates of various sources. The recombinant H. bluephagenesis termed WZY278 generated 22 g L−1 cell dry weight (CDW) containing 80 wt% PHB when cultured in food waste hydrolysates in shake flasks, and it was grown to 70 g L−1 CDW containing 80 wt% PHB in a 7-L bioreactor via fed-batch cultivation. Thus, unsterilizable food waste hydrolysates can become nutrient-rich substrates for PHB production by H. bluephagenesis able to be grown contamination-free under open conditions. • Expression of the operon phaCAB in tandem with the essential gene ompW allows PHB synthesis at all phases of cell growth. • The above recombinant Halomonas bluephagenesis produced PHB in nitrogen-rich media under open unsterile conditions. • The recombinant H. bluephagenesis accumulated PHB on thermally unsterilizable food waste hydrolysates with rich nutrients. [ABSTRACT FROM AUTHOR]

The current study investigates the feasibility of preparing Arabic bread from wheat flour, sweet potato flour, or peeled sweet potatoes based on the nutritional values, technological characteristics, and sensory properties of the final products. First, we analyzed the proximate, elemental, total and individual phytochemical compositions of the raw materials and bread samples. The analysis showed that potassium, calcium, and phosphorus were higher in peels than pulp, in the same manner to the total phenolics, flavonoids, and anti-radical scavenging activities. Phenolic acids and flavonols were quantified, where p-coumaric, feruloyl-D-glucose, eucomic, gallic, and ferulic acids were measured as major phenolic acids in either peels or pulp flours, and their quantities were higher in the peels. Furthermore, we evaluated the effects of wheat substitution on the properties of the dough blends and their final bakery. The results indicated that the fortified samples' nutritional and rheological properties were significantly improved, while their sensory qualities were comparable to those of the control. Thereby, the fortified dough blends presented higher dough stabilities, indicating a wider range of applications. Additionally, after the heat treatment, the fortified breads maintained significantly higher total phenolic, flavonoid, anthocyanin, and carotenoid contents, and total antioxidant activities, implying their accessibility for humans upon consumption. [ABSTRACT FROM AUTHOR]

Chlorophylls are a group of naturally occurring pigments that are responsible for the green color in plants. This pigment group could have numerous health benefits due to its high antioxidant activity, including anti-inflammatory, anti-cancer, and anti-obesity properties. Many food by-products contain a high level of chlorophyll content. These by-products are discarded and considered environmental pollutants if not used as a source of bioactive compounds. The recovery of chlorophylls from food by-products is an interesting approach for increasing the sustainability of food production. This paper provides insight into the properties of chlorophylls and the effect of different treatments on their stability, and then reviews the latest research on the extraction of chlorophylls from a sustainable perspective. [ABSTRACT FROM AUTHOR]

Bioactive compounds, including terpenoids, polyphenols, alkaloids and other nitrogen-containing constituents, exert various beneficial effects arising from their antioxidant and anti-inflammatory properties. These compounds can be found in vegetables, fruits, grains, spices and their derived foods and beverages such as tea, olive oil, fruit juices, wine, chocolate and beer. Agricultural production and the food supply chain are major sources of food wastes, which can become resources, as they are rich in bioactive compounds. The aim of this review is to highlight recent articles demonstrating the numerous potential uses of products and by-products of the agro-food supply chain, which can have various applications. [ABSTRACT FROM AUTHOR]

Food waste is a rich organic matter that can potentially be converted into biogas as a source of renewable energy. The limitation in energy production lies in the presence of volatile fatty acid (VFA) during the anaerobic digestion of food waste due to the high degradation rate. The accumulation of VFA leads to a decrease in pH that exceeds the optimal pH range of 6.8–7.6 for methanogens, thus inhibiting methanogenesis and affecting biogas production. In the present study, a symbiotic culture of bacteria and yeast (SCOBY) and kombucha mixed inoculum and compost was applied as an alternative treatment method to alleviate inhibition. The digestion efficiency was evaluated on pH, total alkalinity (TA), total volatile fatty acid (TVFA), total solid (TS), and volatile solid (VS) throughout the digestion period of 80 days to analyse the stability of the system. The results revealed that SCOBY and kombucha mixed inoculum caused system instability, inducing inhibition at TVFA of 12,874.1 mg/L, while the pH dropped to 5.23. The inhibition in the digestion system with only the SCOBY inoculum occurred at TVFA of 11,908.3 mg/L, and the pH dropped to 5.67. The biogas and methane yield quantified from the mixed inoculum is 8.792E−4 L/L d, comparatively lower than the ethanol pre-fermentation treatment method. These findings indicate that the addition of compost improved the pH, VS, and TVFA. [ABSTRACT FROM AUTHOR]

A significant amount of waste is annually generated worldwide by the supply chain of the food industry. Considering the population growth, the environmental concerns, and the economic opportunities, waste recovery is a promising solution to produce valuable and innovative ingredients for food and nonfood industries. Indeed, plant‐based wastes are rich in dietary fibers (DF), which have relevant technical functionalities such as water/oil holding capacity, swelling capacity, viscosity, texture, and physiological properties such as antioxidant activity, cholesterol, and glucose adsorption capacities. Different drying technologies could be applied to extend the shelf life of fresh DF. However, inappropriate drying technologies or process conditions could adversely affect the functionalities of DF via the hornification phenomenon. Hornification is related to the formation of irreversible hydrogen bindings, van der Waals interactions, and covalent lactone bridges between cellulose fibrils during drying. This review aims to capitalize on the knowledge developed in the wood industry to tackle the hornification phenomenon occurring in the food industry. The mechanisms and the parameters affecting hornification as well as the mitigation strategies used in the wood industry that could be successfully applied to foods are summarized. The application of conventional drying technologies such as air or spray‐drying increased the occurrence of hornification. In contrast, solvent exchange, supercritical drying, freeze‐drying, and spray‐freeze‐drying approaches were considered effective strategies to limit the consequences of this phenomenon. In addition, incorporating capping agents before drying attenuated the hornification. The knowledge summarized in this review can be used as a basis for process design in the valorization of plant‐based wastes and the production of functional DF that present relevant features for the food and packaging industries. [ABSTRACT FROM AUTHOR]

Abstract Background This study evaluated the antioxidant activities of avocado seed extract as affected by solvent for extraction and formulation of microcapsule from the extract. Avocado seed powder was extracted using ethanol, aqueous ethanol, and water as solvents. The extract with the highest bioactive activity was encapsulated using corn and cassava starches as cell wall materials. The antioxidant activity, storage stability, in vitro starch digestibility and Fourier-transform infrared spectroscopy (FTIR) of the microcapsules were evaluated. Results Results indicated that 100% ethanolic extract had the highest flavonoid and total phenolic contents and the highest antioxidant activity. Cassava starch was observed as a better cell wall material for the entrapment of phenolic and bioactive compounds as compared to corn starch. After 30 days of storage at room temperature, there was a significant reduction (p ≤ 0.05) in the DPPH and OH* of the microcapsules, while the total phenol contents increased significantly (p ≤ 0.05). The FTIR showed that the microcapsules contained primarily alcohol (O–H), carbonyl, (C=O,), alkyne (C≡C) and benzene ring functional groups. The microcapsules were able to retain the bioactive contents during storage. Conclusion Microcapsule produced could be used for the formulation of several functional food products and supplements.

Background: Food wastes are an abundant resource that can be effectively valorised by hydrothermal liquefaction to produce bio-fuels. The objective of the European project WASTE2ROAD is to demonstrate the complete value chain from waste collection to engine tests. The principle of hydrothermal liquefaction is well known but there are still many factors that make the science very empirical. Most experiments in the literature are performed on batch reactors. Comparison of results from batch reactors with experiments with continuous reactors are rare in the literature. Methods: Various food wastes were transformed by hydrothermal liquefaction. The resources used and the products from the experiments have been extensively analysed. Two different experimental reactors have been used, a batch reactor and a continuous reactor. This paper presents a dataset of fully documented experiments performed in this project, on food wastes with different compositions, conditions and solvents. The data set is extended with data from the literature. The data was analysed using machine learning analysis and regression techniques. Results: This paper presents experimental results on various food wastes as well as modelling and analysis with machine learning algorithms. The experimental results were used to attempt to establish a link between batch and continuous experiments. The molecular weight of bio-oil from continuous experiments appear higher than that of batch experiments. This may be due to the configuration of our reactor. Conclusions: This paper shows how the use of regression models help with understanding the results, and the importance of process variables and resource composition. A novel data analysis technique gives an insight on the accuracy that can be obtained from these models.

This paper proposes a new thermal, electrical, and water assisted reaction (TEAWAR) technique to convert PMMA and organic residues into graphene and carbonaceous materials. Graphene and other carbon based materials have attracted considerable research interest due to their unique and enhanced properties. Graphene is a particularly promising material for electronic and sensing applications, although preparation is cumbersome requiring high vacuum and other sophisticated facilities to produce quality graphene layers. Graphene and other carbon based materials are commonly prepared from organic and polymer precursors under high thermal conditions. This paper proposes a facile method to prepare graphene and other carbonaceous materials from poly(methyl methacrylate) (PMMA) polymer. PMMA is converted into graphene using a PMMA coated conducting substrate as one electrode in a two electrode electrochemical cell with water electrolyte, where conversion success depends on applied potential, time, temperature, and PMMA layer thickness. We converted PMMA coated on conducting substrates into graphene using 200 V potential for more than 1 h at 50 °C. This technique's suitability for organic residues conversion into carbon was also tested and found to be feasible to convert onion peel and other waste materials into carbon. Converted graphene was applied for photosensing and hydrogen evolution reaction (HER) applications. The formed graphene exhibited good catalytic property comparable to various graphene related materials. [ABSTRACT FROM AUTHOR]

The production of biofuels from microalgae has gained considerable attention due to the rapid diminution of fossil fuels. Despite major advantages, microalgal biofuels deployment still faces obstacles associated with the cost of biomass production and waste disposal. The production could become more cost-effective and feasible if the wastes in the production processes are recycled/reused and the biofuels produced are co-produced with high-value co-products. The aim of this review is to discuss and analyze the importance of recycling/reusing wastes and co-producing high-value products to be implemented with biofuels from microalgal-based processes. Recent advances in circular economy/integration and polygeneration, as proper strategies, are discussed. Circular economy and integration entail the reuse of food wastes, waste biomass, and wastewater in microalgal conversion processes for producing biofuels. The main focus of the section of this review on circular economy is food waste reuse for microalgal production. Polygeneration is the production of multiple products, including a biofuel as the main product and multiple co-products to ensure process cost reduction. The results reported in relevant studies have shown that microalgal growth and metabolite accumulation could be favored by mixotrophic cultivation using wastes from the conversion processes or reused food wastes. The co-production of high-value products, including pharmaceuticals, proteins, carbohydrates, pigments, bioplastics, pellets, and biofertilizers may also favor the sustainability of biofuel production from microalgae. [ABSTRACT FROM AUTHOR]

The consumption of fruits and vegetables involves the disposal of the inedible parts, conveying challenges such as waste management and environment pollution. In recent years, there have been multiple studies aimed at finding alternatives that reduce the negative impact of food/agricultural waste. Since most studies done with by-products recommend their careful selection, the aim of this study was to verify if discarded banana peels could be disinfected until microbiologically safe and to determine if they could still provide nutrients to formulate food products with sensory characteristics acceptable to a consumer market after disinfection. Banana peels were collected from markets, restaurants, and greengrocers. They were disinfected, dried, and pulverized to obtain a flour which was subjected to microbiological and proximal analysis. Once its microbial safety was assured, this flour was incorporated into bakery and pasta products, replacing wheat flour with 5–20% banana peel flour (BPF). The sensory evaluation of the different products was carried out and, after verifying that the products were sensory acceptable, the proximal analysis was implemented. The formulated products were suitable for the addition of BPF up to 10%, in which the Acceptability Index was higher than 80% and significant increases in fiber and fat were achieved. We conclude that waste banana peel flour can be incorporated into bread and pasta products for human consumption to provide nutrients which might contribute to reduce this type of waste and to recover nutrients from otherwise disposed banana peels.

In this research, the application of home composting system as an alternative approach for household organic waste management was investigated. A rotary drum home composter made of galvanized steel was designed and used for the composting process. It consists of two chambers of about 170 L each, and is equipped with sufficient holes to ensure aerobic conditions as well as valves for leachate drainage. Different parameters, including using waste to bulking agent ratio, co-composting using animal manure and introducing charcoal with the feedstock were investigated. The designed reactor proved its efficiency for composting purposes, according to the obtained results regarding the degradation of the organic waste with ease operation and monitoring. The highest reduction volume (85%) in the composted materials was in treatment of 1:0.5 waste to bulking agent, whereas co-composting using animal manure better enhanced the organic matter degradation, as the highest decrease in the C/N ratio (about 62%) was observed in this treatment. No significant effect of the charcoal war recorded regarding the degradation process, but was clear in reducing odors. [ABSTRACT FROM AUTHOR]

The study aimed to investigate the suitability of some food wastes for use in the production of herbal tea and to reveal their properties in terms of bioactive component content, some physical properties and sensory quality. Three new blends consisting of banana, pomegranate, mandarin, eggplant and red onion peels, walnut shell, cherry stalk and corn tassel were infused at different temperatures (70 and 100 °C) and time (3, 4 and 5 min). Corn tassel tea, which has a high phenolic component content (677.7 mg GAE/L), received less sensory acceptance due to its bitter aftertaste. Therefore, walnut shell tea containing moderate phenolic content was the most preferred tea blend. Significant effects of different infusion temperatures and times on the color indices of teas were also demonstrated. The sensory properties of samples infused for 3 min were more acceptable. The highest correlation coefficients were calculated between total phenolic compounds and subjective odor parameters. Utilization of mandarin, pomegranate, banana, eggplant and red onion peels, walnut shell, corn tassel and cherry stalk in formulating a functional and an alternative food product can be attractive to consumers and industrial producers due to their affordability and high bioactivity.

Featured Application: Several promising aqueous mixtures are selected for the fast extraction of functional antioxidant mixtures from apple and grape pomaces. Polyphenols have become a research target due to their antioxidant, anti-inflammatory and antimicrobial activity. Obtention via extraction from natural sources includes the revalorization of food wastes such as grape pomace (GP) or apple pomace (AP). In this work, GP and AP were submitted to a liquid–solid extraction using different solvents of industrial interest. Process kinetics were studied measuring the total phenolic content (TPC) and antioxidant capacity (AC), while the extraction liquor composition was analyzed employing chromatographic methods. Extraction processes using water-solvent mixtures stood out as the better options, with a particular preference for water 30%–ethanol 70% (v/v) at 90 °C, a mixture that quickly extracts up to 68.46 mg GAE/gds (Gallic Acid Equivalent per gram dry solid) and 122.67 TEAC/gds (TROLOX equivalent antioxidant capacity per gram dry solid) in case of GP, while ethylene water 10%–ethylene glycol 90% (v/v) at 70 °C allows to reach 27.19 mg GAE/gds and 27.45 TEAC/gds, in the case of AP. These extraction processes can be well-described by a second-order kinetic model that includes a solubility-related parameter for the first and fast-washing and two parameters for the slow mass transfer controlled second extraction phase. AP liquors were found to be rich in quercetin with different sugar moieties and GP extracts highlighted flavonols, cinnamic acids, and anthocyanins. Therefore, using identical extraction conditions for AP and GP and a comparative kinetic analysis of TPC and AC results for the first time, we concluded that ethanol/water mixtures are adequate solvents for polyphenols extraction due to their high efficiency and environmentally benign nature. [ABSTRACT FROM AUTHOR]