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Although total carbon (TC) is an important component of fine particulate matter (PM 2.5 : particulate matter with aerodynamic diameter of <2.5 μm); its sources remain partially unidentified, especially in coastal urban areas. With ongoing development of the global economy and maritime activities, ship-generated TC emissions in port areas cannot be neglected. In this study, from September 11, 2017 to August 31, 2018, we collected 355 p.m. 2.5 samples in Qingdao, China, to determine the water-soluble ion concentrations, TC concentrations, and stable carbon isotopes (δ13C TC). During the open fishing season (OFS; September 11, 2017 to April 30, 2018) and the closed fishing season (CFS; May 1, 2018 to August 31, 2018), the TC concentrations were 9.30 ± 5.38 μg/m3 and 3.36 ± 2.10 μg/m3 respectively, and the corresponding δ13C TC values were −24.53‰ ± 1.17‰ and −27.03‰ ± 0.91‰, respectively, indicating significant differences (p < 0.05) between the two periods. The differences in TC concentrations and the δ13C TC values between the OFS and CFS reflect changes in the source of contamination. Bayesian model was used to quantify the contributions of different TC sources, revealing that ship emissions accounted for approximately 35.3% of the total, which was close to the contribution from the largest source, i.e., motor vehicles (39%). Using the ship emission inventory, Qingdao's ship emissions were further quantified at 455 metric tons, representing 35%–40% of the total TC emissions around Qingdao. Notably, fishing ships contributed approximately 40% of the total ship emissions. These findings underscore the considerable impact of ship emissions, particularly those from fishing ships, on TC concentrations in coastal urban areas. [Display omitted] • Motor vehicle exhaust is the most important source for total carbon throughout the year. • Ship emissions accounted for up to 41% of TC during the non-closed fishing season. • The fishing ship emissions contributed about 40% of TC of total ship emissions. [ABSTRACT FROM AUTHOR]

With the increase in global population, environmental hazards, climate change, energy limitations, and a decrease in agricultural land, emerging techniques are critical to raising and enhancing food production and quality. This review aims to draw attention to the latest developments in technology that guarantee the quality and safety of food. It is devoted to highlighting several key materials-based derivatives, extraction methods, chemistry, mechanisms of action, safety considerations, and various other uses. The review discusses the utilization of cutting-edge food materials, including aerogels, C -dots, nanoparticles, nanoemulsions, and conjugates, in several areas of food processing and preservation. These materials offer unique properties that contribute to improving food quality, safety, and shelf life. The review also addresses research challenges and identifies future trends in this field. These challenges may involve optimising synthesis processes, understanding the long-term effects of these materials on human health and the environment, and developing sustainable production methods. By addressing these challenges, researchers can unlock the full potential of advanced food materials. In conclusion, this review underscores the significance of emerging techniques and materials in ensuring food quality and safety. The integration of science and engineering in the development of advanced food materials opens up new possibilities for sustainable food production and preservation. By addressing current challenges and focusing on future trends, researchers can contribute to the advancement of this field and meet growing global food demands. • Integrating interdisciplinary scientific knowledge is key to the development of engineered materials. • Various engineered materials used to ensure food safety and quality were summarized. • Engineered materials can serve as both food ingredients and protective agents. • Engineered materials can be used in food and feed processing at any stage. [ABSTRACT FROM AUTHOR]

Abstract The marine aerosols is mainly produced primary sea salt and secondary form of non-sea salt (nss) sulfate and organic species from marine emission, but get modified significantly by the anthropogenic and terrestrial materials, such as total carbon (TC) and total nitrogen (TN), which transported by the atmospheric circulation from land to the ocean. Rarely studies focus on the TC and TN in marine aerosol in the open ocean due to the sampling difficulty, let alone the annual observation. Concentrations of TC and TN, and their isotope compositions (δ13C-TC and δ15N-TN) were measured in total suspended particulate (TSP) which sampled at Yongxing Island over the South China Sea from March 2014 to February 2015, and coastal mega-city Guangzhou in April/May and October/November 2014. The annual average concentrations of TC and TN at Yongxing Island were 4.20 ± 2.38 μg m−3 and 0.77 ± 0.47 μg m−3, respectively. Much higher concentration of TC and TN were observed at Guangzhou. Contributions of NO 3 − and NH 4 + (inorganic nitrogen, IN) to TN at Yongxing Island averaged 55.7% and 6.8%, respectively, while they averaged 27.4% and 12.2% at Guangzhou, respectively. The average values of δ15N in TN were +0.7 ± 3.3‰, +6.8 ± 6.3‰ and −0.7 ± 2.7‰ during winter, transitional and warm seasons, respectively, with an annual average value of +1.1 ± 4.3‰. The δ13C of TC varied from −16.2 to −26.8‰, with an annual average value of −22.7‰. The average of values of δ13C were −22.9 ± 1.7‰, −22.9 ± 1.4‰, and −22.4 ± 2.6‰ during winter, transitional and warm seasons, respectively. The average values of δ15N in TN and δ13C of TC were +13.2 ± 0.9‰ and −25.8 ± 0.4‰ in winter season, +13.6 ± 0.8‰ and - 26.5 ± 0.3‰ in warm season at Guangzhou, respectively. Based on aerosol δ15N and δ13C values, the marine realm may be an important source of aerosol TN, while aerosol TC may dominantly contributed by the combustion of fossil fuels and biomass burning from continental mass over the South China Sea. The secondary aerosol formation and long-range transport on aerosol chemistry also varied the concentrations and isotopic composition of TN and TC at Yongxing Island. Highlights • δ13C-TC and δ15N-TN of 1-year aerosol at Yongxing Island over the South China Sea were investigated. • NO 3 −, and ON (organic nitrogen) were major components of TN, accounted for 55.7% and 37.5%, respectively. • Marine emission and fixed nitrogen were important sources for TN. • Combustion of fossil fuels from continent was an important common source for both TN and TC. [ABSTRACT FROM AUTHOR]

To constrain sources of anthropogenic nitrogen (N) deposition is critical for effective reduction of reactive N emissions and better evaluation of N deposition effects. This study measured δ 15 N signatures of nitrate (NO 3 − ), ammonium (NH 4 + ) and total dissolved N (TDN) in precipitation at Guiyang, southwestern China and estimated contributions of dominant N sources using a Bayesian isotope mixing model. For NO 3 − , the contribution of non-fossil N oxides (NO x , mainly from biomass burning (24 ± 12%) and microbial N cycle (26 ± 5%)) equals that of fossil NO x , to which vehicle exhausts (31 ± 19%) contributed more than coal combustion (19 ± 9%). For NH 4 + , ammonia (NH 3 ) from volatilization sources (mainly animal wastes (22 ± 12%) and fertilizers (22 ± 10%)) contributed less than NH 3 from combustion sources (mainly biomass burning (17 ± 8%), vehicle exhausts (19 ± 11%) and coal combustions (19 ± 12%)). Dissolved organic N (DON) accounted for 41% in precipitation TDN deposition during the study period. Precipitation DON had higher δ 15 N values in cooler months (13.1‰) than in warmer months (−7.0‰), indicating the dominance of primary and secondary ON sources, respectively. These results newly underscored the importance of non-fossil NO x , fossil NH 3 and organic N in precipitation N inputs of urban environments. [ABSTRACT FROM AUTHOR]

Black Pepper (Piper nigrum) also known as black gold is one of the most traded spices in the world. Recent instances have reflected increased numbers of export rejections due to the presence of Escherichia coli , Salmonella and a high load of microbes. This study presents the potential of a novel combination of microwave-vacuum–steam treatment that is capable of bringing down the high microbial load in the product at relatively low temperatures. The treatment has resulted in 7.59 log reduction for E. coli, 9.25 log reduction in Salmonella and around 3.28 log reduction in total mesophilic plate count. The optimized condition was found to be 4.19 W/g MW power density, 3 s steam time and 134 s process time. The process optimized and developed in this study with low microwave power density has the potential to be used industrially for bulk decontamination of spices. • The potential of the novel combination of microwave steam vacuum for decontamination was evaluated. • More than 7 log reductions in E. coli and Salmonella were obtained. • In total mesophilic plate count, 3.28 log reduction was obtained. [ABSTRACT FROM AUTHOR]

Black carbon (BC) aerosols emitted from incomplete combustion of fossil fuels, biofuels, and biomass have significant effects on the environment and human health. Combustion-derived BC aerosols are an important component in haze pollution. High concentrations of BC aerosols were found in fine particulate matter (PM 2.5) in China, and source apportionment was the strategy underpinning targeted mitigation actions. Here, we present a Bayesian statistical model, a three-dimensional array of a stable carbon isotope (δ13C) and the ratios of non-sea-salt K+ to BC (nss-K+/BC) and ΔBC/ΔCO that is a reasonably inexpensive and rapid way to constrain BC source apportionments. This study analyzed 551 daily PM 2.5 samples collected in January 2018 in 18 large cities and at 1 remote site scattered across China. The results show that BC concentrations were generally higher in cities in northern China than they were in cities in southern China. Source apportionments indicate that BC in 44% of cities was mainly from liquid fuel combustion. In other sites, including 39% of cities, one suburban site, and one remote site, BC was mainly from biomass burning. These findings suggest that to improve air quality, the Chinese government should further strengthen controls on liquid fuel combustion and consider controlling biomass burning. • Using δ13C, K+/BC, and ΔBC/ΔCO, to identify black carbon sources across China. • Black carbon was mainly from liquid fuel combustion in 44% of the large cities in China. • Biomass burning was also an important source of black carbon. [ABSTRACT FROM AUTHOR]

NO 3 − concentration, nitrogen and oxygen isotopic compositions (δ 15 N and δ 18 O) of NO 3 − were measured in total suspended particulates (TSP) at Yongxing Island in the South China Sea (SCS) between Feb. 2013 and Jan. 2014, as well as on two cruises in the northern South China Sea (NSCS). Measurements aimed to identify NO 3 − sources, and possible chemical formation processes of NO 3 − . The δ 15 N and δ 18 O of NO 3 − in TSP at Yongxing Island ranged from −2.5 to +4.9‰, and +48.1 to +99.0‰, with annual weighted averages of +1.5‰ and +83.2‰, respectively. Both δ 15 N and δ 18 O had higher values in cool months, indicating that NO x sources and oxidants were different between seasons. In cool months, NO x was mainly from anthropogenic sources, particularly from coal combustion in South China, resulting in high nitrogen deposition that was oxidized by O 3 to NO 3 − . In warm months, natural emissions were an important source of NO x . TSP samples in the NSCS had higher NO 3 − concentrations, higher δ 15 N and lower δ 18 O values than samples from Yongxing Island over the same period. This suggests that atmospheric processes caused a decrease in NO 3 − concentrations and δ 15 N but increase in δ 18 O from coast to remote marine. Assuming to oxygen atoms were derived from O 3 during transport in cool months, the mean ratio of NO 3 − formed by NO x to total NO 3 − was calculated to be 47.9%. This suggests the mean loss ratio of NO x was 89% while the loss ratio of NO 3 − was 87% during transport between Chinese coastal areas and Yongxing Island in Nov., 2013. [ABSTRACT FROM AUTHOR]

It is generally difficult to measure atmospheric gaseous ammonia concentration and to identify its sources by isotopic technique due to the isotopic fractionation after it enters the atmosphere. In this study, Rayleigh model was successfully used to quantify atmospheric concentration and isotopic composition of gaseous ammonia based on sampling of 20 rain events from October 1st, 2008 to September 30, 2009 in Guiyang, southwest China. The estimated gaseous ammonia concentration was 25.7 ± 36.3 μg/m 3 and estimated isotopic composition was − 16.8 ± 4.9‰ in Guiyang. The study also showed that estimated enrichment factor was + 10.4 ± 4.3‰, inferring that large nitrogen isotopic fractionation occurred during exchange reactions in most of the rain events. The atmospheric ammonium deposition was further estimated to be 38.1 kg/ha/year. However, there is no validation for the approach from an actual gas phase NH 3 measurement to examine the model in this study. [ABSTRACT FROM AUTHOR]

Sulfate concentrations and sulfur isotopic compositions were measured in rainwater in Guiyang city in Southwest China between October 2008 and September 2009 to identify sulfur sources and their impacts on sulfur isotopic composition. The δ 34 S values of 1235 samples collected during this period ranged from − 12.0 to + 9.4‰, with a volume-weighted mean of − 2.8 ± 9.8‰, suggesting that rainwater sulfate in Guiyang was mainly derived from SO 2 produced during coal combustion. The δ 34 S values of rainwater sulfate increased from 1987 to 2009, with an increment of about + 0.16‰ per year, reflecting a gradual reduction in 34 S-depleted SO 2 emitted during coal combustion. Seasonal variations in δ 34 S values were pronounced, with higher values in winter than in summer. Long-distance transport of SO 2 from coal burned in northern cities (which was higher than the component from southern cities), and more importantly, the aqueous oxidation of SO 2 during transport affected the seasonal variation of rainwater δ 34 S values in Guiyang. Temperature-dependent aqueous oxidation of SO 2 suggested that lower rainwater δ 34 S coincides with higher temperature. [ABSTRACT FROM AUTHOR]

Highlights: [•] Polyphenol oxidase activity in grapes was analyzed with different SSIB treatment. [•] SSIB treatment could significantly decrease the drying time to less than 20h. [•] Green–yellow raisins could be obtained without any chemical treatment. [•] The effect of SSIB time on drying behavior is more significant than temperature. [•] Most favorable conditions were proposed by reviewing drying kinetics and color. [Copyright &y& Elsevier]

Abstract: Nitrogen isotopes of ammonium (δ15N–NH4 +) in precipitation have been analyzed, to study their monthly variations, from Oct. 2008 to Sep. 2009 at Guiyang, Southwest China. δ15N–NH4 + values were higher in winter and lower in summer showing a strong sine curve. In summer (rainy season), raindrop may remove more light ammonia by washout process, because raindrop incorporated 15NH3 preferentially while left the 14N in the atmosphere. At the same time, longer sunshine times imply more hv for producing H2SO4 of SO2 to H2SO4, which accelerates gaseous to particle conversion of NH3 to (NH4)2SO4 by unidirectional reactions for isotopic enriched 14N. The above two aspects can somewhat cause the seasonal variation of nitrogen isotopic composition, but are not the main or direct reasons. The temperature has an opposite trend with seasonal variation of δ15N values. The temperature not only causes seasonal variation of δ15N values, but also increases the volatilization rate of NH3 and microbial activities. And there is a robust linear relationship between temperature and δ15N, showing that the temperature is the main factor to decide the monthly variation of δ15N–NH4 +. [Copyright &y& Elsevier]

Epilithic mosses are characterized by insulation from substratum N and hence meet their N demand only by deposited N. This study investigated tissue C, total Chl and δ 13C of epilithic mosses along 2 transects across Guiyang urban (SW China), aiming at testing their responses to N deposition. Tissue C and total Chl decreased from the urban to rural, but δ 13Cmoss became less negative. With measurements of atmospheric CO2 and δ 13CO2, elevated N deposition was inferred as a primary factor for changes in moss C and isotopic signatures. Correlations between total Chl, tissue C and N signals indicated a nutritional effect on C fixation of epilithic mosses, but the response of δ 13Cmoss to N deposition could not be clearly differentiated from effects of other factors. Collective evidences suggest that C signals of epilithic mosses are useful proxies for N deposition but further works on physiological mechanisms are still needed. [Copyright &y& Elsevier]

In urban cities in Southern China, the tissue S/N ratios of epilithic mosses (Haplocladium microphyllum), varied widely from 0.11 to 0.19, are strongly related to some atmospheric chemical parameters (e.g. rainwater SO4 2−/NH4 + ratios, each people SO2 emission). If tissue S/N ratios in the healthy moss species tend to maintain a constant ratio of 0.15 in unpolluted area, our study cities can be divided into two classes: class I (S/N > 0.15, S excess) and class II (S/N < 0.15, N excess), possibly indicative of stronger industrial activity and higher density of population, respectively. Mosses in all these cities obtained S and N from rainwater at a similar ratio. Sulphur and N isotope ratios in mosses are found significantly linearly correlated with local coal δ 34S and NH4 +–N wet deposition, respectively, indicating that local coal and animal NH3 are the major atmospheric S and N sources. [Copyright &y& Elsevier]

The application of geochemical signals in mosses is more and more popular to investigate the deposition of atmospheric pollutants, but it is unclear whether records of atmospheric sulfur in mosses differ between their diverse habitats. This study aimed to investigate the influence of growing condition on tissue sulfur and δ 34S of Haplocladium microphyllum. Epilithic and terricolous mosses in open fields, mosses under different canopy conditions were considered. We found that tissue sulfur and δ 34S of mosses under different habitats were not consistent and could not be compared for atmospheric sulfur research with each other even collected at the same site, moss sulfur and δ 34S records would be distorted by subsoil and upper canopies in different degrees, which possibly mislead the interpretation of atmospheric sulfur level and sources. Consequently, mosses on open rocks can be used reliably to assess atmospheric-derived sulfur in view of their identical sulfur and δ 34S evidences. [Copyright &y& Elsevier]

Abstract: Nitrogen concentration and δ 15N in 175 epilithic moss samples were investigated along four directions from urban to rural sites in Guiyang, SW China. The spatial variations of moss N concentration and δ 15N revealed that atmospheric N deposition is dominated by NH x -N from two major sources (urban sewage NH3 and agricultural NH3), the deposition of urban-derived NH x followed a point source pattern characterized by an exponential decline with distance from the urban center, while the agricultural-derived NH x was shown to be a non-point source. The relationship between moss N concentration and distance (y =1.5e−0.13x +1.26) indicated that the maximum transporting distance of urban-derived NH x averaged 41km from the urban center, and it could be determined from the relationship between moss δ 15N and distance [y =2.54ln(x)−12.227] that urban-derived NH x was proportionally lower than agricultural-derived NH x in N deposition at sites beyond 17.2km from the urban center. Consequently, the variation of urban-derived NH x with distance from the urban center could be modeled as y =56.272e−0.116x −0.481 in the Guiyang area. [Copyright &y& Elsevier]

Atmospheric ambient gaseous ammonia (NH 3), the most abundant alkaline gas, affects public health and climate change through its key role in the formation of secondary aerosols via reactions with acidic gases. Estimation of the contributions of ammonia sources is very challenging in the urban atmosphere. Stable nitrogen isotope ratio (δ15N) measurements have shown that urban aerosol NH 4 + and gaseous NH 3 are derived from fossil fuel combustion-related (FF) sources, such as coal combustion, NH 3 slip, and vehicle exhaust, and volatilization-related sources, such as agriculture and urban water volatilization. Biomass burning (BB) sources, especially residential biofuel, can produce vast quantities of NH 3 and other pollutants and may greatly influence air quality and contribute to increased urban NH 3 emissions. In the present study, we continually collected PM 2.5 samples at three urban sites in Central China during autumn and analyzed the major water-soluble ions and δ15N values of aerosol NH 4 +. The concentrations of NH 4 + increased as the temperature decreased close to winter, whereas the δ15N values did not show this pattern. According to the Bayesian model after isotope fractionation correction, FF sources contributed to 56.4 ± 17.1%, 46.4 ± 18.2%, and 51.8 ± 14.9% of aerosol NH 4 + in Nanchang, Wuhan, and Changsha, respectively, throughout autumn. The contributions from BB sources were 34.5 ± 20.4%, 46.4 ± 21.4%, and 40.4 ± 17.4% for Nanchang, Wuhan, and Changsha, respectively. We also found the fraction of aerosol NH 4 + from BB increased in all three cities from September to November 2017, which was likely caused by increased heating demands with the decrease in temperature during the season. Furthermore, BB was responsible for a severe haze event (maximum PM 2.5 of 205.69 μg/m3) in Nanchang. These findings suggest government controls to improve air quality should include BB sources in addition to FF sources. Image 1 • Aerosol NH 4 + was mainly derived from fossil fuel combustion-related sources. • Biomass burning's contribution to aerosol NH 4 + increased as the temperature decreased. • Biomass burning greatly contributed to a severe haze event in Nanchang. [ABSTRACT FROM AUTHOR]

The mechanism of ionic wind and electric field of electrohydrodynamic (EHD) drying dehydration stress on the biochemical and molecular basis of bee pollen is still unclear. In this study, metabolomics and proteomics were employed to analyze the changes in biochemicals and small-molecule metabolic compounds of bee pollen during the drying process using needle-to-plate and plate-to-plate electrode system. The results show that ionic wind and electric field contributed 85.0% and 15.0% respectively to the dehydration characteristics, with the electric field having a greater effect on the quality parameters. As compared to ionic wind, the ribosome, the citric acid cycle (TCA cycle), and proteasome pathway played a positive role in regulating the abiotic and biochemical responses of electric field dehydration. Both ionic wind and electric field changed the expression of functional proteins related to amino acid metabolism pathways, resulting in a decrease in the expression of characteristic metabolites such as L-phenylalanine, L-aspartic acid, and L-pyroglutamic acid from 114.27 × 107, 5.31 × 107, and 142.55 × 107 in fresh rape bee pollen to 57.46 × 107, 3.32 × 107, and 57.46 × 107 in needle-to-plate (N-P) electrode treated and 61.25 × 107, 2.47 × 107, as well as 33.82 × 107 in plate-to-plate (P-P) electrode treated samples. Additionally, the differential expression of proteasome pathway and the destruction of the structural integrity of the cell wall storing phenolic compounds resulted in the further interaction of protein-phenolic supercomplexes, which in turn changed the content of free phenolic acids in rape bee pollen. These findings elucidated the biochemical regulation strategy and protein-phenolic compound interaction mechanism of rape bee pollen during EHD drying processing, and further emphasized the synergistic mechanism of ionic wind and electric field. [Display omitted] • Separate the respective roles of electric field and ionic wind. • Ionic wind has a greater influence on the drying characteristic parameters. • Electric field has significant effect on pathways related to protein denaturation. • Electrohydrodynamic drying affected the protein-phenolic acid interactions. • Combined metabolomics and proteomics study on the phytochemicals formation. [ABSTRACT FROM AUTHOR]

• Based on the diffuse interface theory, a simple wetting immersed-boundary scheme for curved boundaries is developed. • The scheme performs well in dealing with the binary and ternary flows on both stationary and moving curved boundaries. • Case studies show the proposed scheme has good accuracy and mass conservation. In this paper, a simple diffuse interface immersed-boundary scheme is developed for multiphase flows with curved boundaries. With this method, the wetting boundary conditions (WBC) for stationary and moving curved boundaries can also be dealt in a similar manner as the flat boundaries. The main idea is cultivated by considering two virtual layers of Lagrangian grid points to interpolate the actual solid curved boundary. This scheme has the advantage of simple implication, it can successfully accommodate both the stationery and complex moving curved boundaries along with good accuracy and mass conservation property. A lattice Boltzmann method (LBM) framework is developed to incorporate the proposed immersed-boundary scheme. To test the present method, several binary and multiphase flow problems are simulated. The numerical results are compared with theoretical and experimental results from literature which showed that the method can easily and efficiently simulate the ternary flows and two-phase flows on the curved surfaces with high accuracy and mass conservation. [ABSTRACT FROM AUTHOR]

This study evaluated the effects of postharvest ripening (0–6 days, D0–6) on cell wall pectin profile, infrared-assisted hot air-drying characteristics, and sugar content. Results showed that during postharvest ripening progress, the content of water-soluble pectin (WSP) and chelate-soluble pectin (CSP) increased while the content of Na 2 CO 3 -soluble pectin (NSP) and hemicellulose (HC) decreased. In addition, the average molecular weight of WSP increased while the average molecular weight of NSP decreased. Secondly, the drying time of plums with different postharvest ripening periods was in the order: D3 < D4 < D2 < D1 < D0 < D5 < D6. Furthermore, the sugar content of dried plums was mainly influenced by drying time, with three stages of sugar changes observed, tied to moisture content: (1) Sucrose hydrolyzes (50–85%); (2) Fructose and glucose degrade (15–50%); (3) Sorbitol degrades (15–42%). These findings indicate that the transformation of cell wall pectin profile during the postharvest ripening process alters drying behavior and regulates the sugar content of dried plums. Galacturonic acid (PubChem CID: 439215); Acetone (PubChem CID: 180); Distilled water (PubChem CID: 962); Trans-1,2-Diaminocyclohexane-N, N, N, N′-tetraacetic acid (PubChem CID: 2723845); Na 2 CO 3 (PubChem CID: 10340); Glucose (PubChem CID: 5793); fructose (PubChem CID: 2723872) sucrose (PubChem CID: 5988) sorbitol (PubChem CID: 5780) and Sodium borohydride (PubChem CID: 4311764). [Display omitted] • Postharvest ripening affects plum's drying characteristics and dried plum's sugar content. • Postharvest ripening process alters cell wall polysaccharide content. • Molecular weight of pectin and microstructure were used to explore quality changes. • Postharvest ripening process affects the water distribution status of plums. • Plum drying has three sugar change stages tied to moisture content. [ABSTRACT FROM AUTHOR]

This work aims to develop an evacuated tube solar-electric hybrid drying setup and enhance its performance using evacuated collector and photovoltaic systems. The setup performance was evaluated by dehydration of lotus bee pollen using two different strategies inducing solar heating drying and mixed heating drying at three different temperatures (40, 50, and 60 °C). The system was also compared with open sun drying. Compared with open sun drying, about 45%, 23%, 30%, and 41% reduction in the process time was induced by solar heating drying and mixed heating drying (40, 50, and 60 °C), respectively. For both solar heating and mixed heating drying, the mechanical energy, thermal energy generated by electric heating tubes, and radiation thermal energy accounted for were in the range of 12.2–38.5%, 0.0–15.3%, and 60.5–87.8%, respectively. From the perspective of drying efficiency and energy consumption, the developed evacuated tube solar-electric hybrid drying setup was more beneficial under mixed heating drying at 40 and 50 °C. The dryer efficiencies under the cases of mixed heating drying at 40, 50 °C were 48% and 34% higher than that of solar heating drying, while mixed heating drying had lower total energy consumption, specific energy consumption and specific electric energy consumption. The developed equipment can effectively reduce greenhouse gas emissions and has a short payback period of 1.24 years. Based on the findings of this research, it could be concluded that, resulting in decreased drying time, GHG emissions and enhanced energy efficiency, the developed equipment is a promising drying technology. • The developed hybrid dryer had good drying performance and economic benefits. • The mixed heating mode had higher drying efficiency and lower energy consumption. • Collector, heating tube and auto-sunshade cooperated to achieve constant temperature. • The intervention of heating tube on total heat energy didn't exceed 10%. [ABSTRACT FROM AUTHOR]

Crystallization degrades the physicochemical properties of honey and reduces consumer acceptance. To address this issue, radiofrequency was developed to investigate the decrystallization efficiency and quality impact mechanism of rape honey. The results showed that radiofrequency significantly decreased the number and size of crystals, leading to shortening the decrystallization time to less than 10 min. The response surface optimization methodology further indicated that the highest decrystallization rate (98.72 ± 0.34 %) and lower 5-Hydroxymethylfurfural (2.45 ± 0.12 mg/kg) contents were obtained. Furthermore, radiofrequency changed the honey from a pseudoplastic into a Newtonian fluid efficiently due to the volumetric heating feature. It is worth noting that the inactivation of glucose oxidase reduced the antibacterial capacity, while the increase in total phenolic and flavonoid contents improved the antioxidant capacity of rape honey. In summary, current findings indicated that radiofrequency is a potential alternative decrystallization technology for water baths. [Display omitted] • Radiofrequency heating shortens the decrystallisation time to less than 10 min. • Radiofrequency heating changed the honey from a pseudoplastic into a Newtonian fluid. • The increase of total phenols and flavonoids improves the antioxidant capacity. • The inactivation of glucose oxidase reduced the antibacterial capacity. [ABSTRACT FROM AUTHOR]

• The method can be applied to both miscible and immiscible ternary flow problems. • The method can deal with ternary flows with reduction consistency and conservation of mass. • The method can effectively simulate the ternary flows with a large density ratio up to 1200. In this paper, a generalized conservative phase-field simplified lattice Boltzmann method is proposed, which is suitable for both miscible and immiscible ternary flow problems. This method extends our earlier simplified multiphase lattice Boltzmann method (SMLBM) (Chen et al., 2018a) for two-phase flows to the ternary flows by using a generalized conservative equation with Lagrange multiplier to control the evolution of the interface and ensures the conservations of the volume and total mass of each phase. Moreover, the good stability of the SMLBM is utilized for solving the interface problems with large gradients induced by large density ratios between different fluid components. To validate the present method, several ternary flow examples are simulated. The numerical results show that the method can effectively simulate the ternary flows with a density ratio up to 1200 and can be applied to accurately simulate the miscible ternary flows with satisfying the reduction consistency conditions. [ABSTRACT FROM AUTHOR]

[Display omitted] • Effect of ripening on pulsed vacuum drying behavior of goji berry was explored. • Ripening stage changes goji's phytochemicals, ultrastructure and moisture status. • Ripening stage influences goji drying characteristics and physicochemical quality. • Lower maturity samples hold shorter drying time, while suffer more severe browning. • PVD promoted rupture and transformation of pectin and by thus enhanced browning. In current work, the effect of ripening stages (I, II, and III) on pulsed vacuum drying (PVD) behavior of goji berry was explored. The shortest drying time of goji berry was observed at stage I (6.99 h) which was 13.95 %, and 28.85 % shorter than those at stages II, and III, respectively. This phenomenon was closely associated with the ripening stage, as contributed by the initial physiochemical differences, ultrastructure alterations, and moisture distribution. In addition, lower maturity suffered more severe browning, primarily due to the enzymatic and non-enzymatic reactions of phenolics, followed by pigment degradation and the Maillard reaction. Additionally, the PVD process promoted the rupture and transformation of the pectin fractions, also causing browning either directly or indirectly through participation in other chemical reactions. These findings suggest that the appropriate ripening stage of goji berry should be considered as having a significant impact on drying behaviors and quality attributes. [ABSTRACT FROM AUTHOR]

• Effectiveness of geothermal/solar drying system for onion in cloudy and rainy weather is studied. • Energy, exergy and environmental analysis of the drying system have been determined. • Solar fraction and geothermal fraction have been verified. • Average payback period of the system was found to be 0.74 years. • Low total color change of dried onion was observed. Preservation of onion surplus during rainy and cloudy days is a big challenge for farmers in the so-far area in northern Sahara of Algeria. Thus, available renewable energies such as geo-exchange and solar energy could be an effective solution. In the current study, an insulated north wall solar dryer (INWSD) integrated with geo-exchange heat exchanger (GHE) with inlet temperature of 80 °C was tested for drying onion slices under cloudy and rainy weather. Solar radiation and ambient temperature were in the range of 0–447 W m−2 and 9.65–26.53 °C, respectively. Drying process took 28 consecutive hours. Average diffusivity was found to be 2.81 × 10−10 m2 s−1 by considering the variation of relative humidity and temperature inside the drying chamber. Specific energy consumption varied between 0.66 and 1.75 kWh/kg with an average of 1.71 kWh/kg. Thermal efficiency was in the range of 1.48%–48.90%, with an average value of 9.52%. The low CO 2 emissions of 46.69 kg/year and average payback period of 0.74 year were obtained using the INWSD. Dried onion was with low total color change at 3.79 compared to fresh samples. Therefore, INWSD is a promising technique by comprehensively considering the 3E (energy, economic, economic-environmental) and color analysis. [ABSTRACT FROM AUTHOR]

Seedless grapes blanched by high-humidity hot air impingement blanching (HHAIB) at different temperatures (90, 100, 110, and 120°C) and several durations (30, 60, 90, and 120s) were air-dried at temperatures ranging from 55 to 70°C. The PPO activity, drying kinetics, and the product color parameters were investigated to evaluate the effect of HHAIB on drying kinetics and color of seedless grapes. The results clearly show that HHAIB not only extensively decreases the drying time but also effectively inhibits enzymatic browning and results in desirable green–yellow or green raisins. In view of the PPO residual activity, drying kinetics and color attributes, HHAIB at 110°C for 90s followed by air drying at 60°C are proposed as the most favorable conditions for drying grapes. These findings indicate a new pretreatment method to try to enhance both the drying kinetics and quality of seedless grapes. Industrial relevance: Drying grapes into raisins is a major processing method in almost all grape-growing countries. Drying grapes is more difficult than some other biological materials, since a thin-layer of wax covers on its surface peel. Currently, chemical pre-treatment methods are used frequently to dissolve the wax layer and accelerate dry rate. However, the chemical additive residue in the raisins may cause food safety problems and how to deal with larger quantities of corrosive chemicals is a serious problem. HHAIB is a new and effective thermal treatment technology with advantages such as minimum solids loss, uniform, rapid and energy-efficient blanching process. The current work indicates that HHAIB may be a useful non-chemical pretreatment technology for seedless grape drying, which can not only accelerate drying kinetics but also improve color parameters of seedless grape. [ABSTRACT FROM AUTHOR]

Abstract: Elemental (S and N) and isotopic (δ 34S and δ 15N) contents in the moss Haplocladium microphyllum at urban, rural and forested sites in acid rain area of South China have been analyzed for comparisons to show whether they are different and can be effectively used to identify S and N sources of atmospheric deposition. Average moss S content at rural sites (0.29 ± 0.06%) was found to be in between those at urban (0.35 ± 0.05%) and forested (0.25 ± 0.04%) sites, which are significantly different. Average N contents of urban (2.60 ± 0.56%) and rural mosses (2.84 ± 0.77%) are not significantly different, while both are significantly different to that of forested mosses at most areas, indicating that the atmosphere over rural sites has been polluted by N as seriously as that over urban sites. Nitrogen supply, relative to S supply, was in excess of the requirement for protein synthesis, especially at rural and forested sites. Moss stable isotope signatures have been proven to be effective tools for deciphering atmospheric S and N sources at these sites. Through moss δ 34S signatures, we found that atmospheric S at urban and forested sites was mainly from local coal combustion and domestic biomass burning, respectively, whereas northerly air masses contributed more S to forested sites. The relatively negative moss δ 15N values (−7.5 ± 3.0, −3.4 ± 2.1 and −0.8 ± 2.1‰) demonstrated that the main form in the N deposition was NHx in these sites. More negative δ 15N signatures in urban mosses (−7.5 ± 3.0‰) indicated the contribution of NH3 released from untreated city sewage and wastes, while relatively less negative δ 15N for rural and forested mosses (3.4 ± 2.1 and −0.8 ± 2.1‰) was largely derived from agricultural NH3. [Copyright &y& Elsevier]

Moisturizing strategy that controls the water evaporation rate of the wet material and thus the relative humidity in the drying chamber was proposed for hot air drying of mushroom slices for the first time. To assess the effectiveness of moisturizing strategy, drying kinetics, moisture diffusivities, mass transfer coefficients, surface color and rehydration capacity of dried products, energy and exergy efficiencies were evaluated. Mushroom slices were dried at constant drying temperature of 60 °C and air velocity of 3 m/s. The strategies of moisturizing for 0, 15, 30, and 45 min were applied in the initial drying stage. Compared to the continuous dehumidifying strategy (moisturizing time is 0 min), the strategies of moisturizing for 15 and 30 min reduced drying time by 5% and 15%, respectively. The proper moisturizing time (30 min) enhanced the heat transfer by increasing the enthalpy of the drying air, improved surface color, and increased rehydration capacity of dried mushroom slices by reducing cell shrinkage. The energy utilization and energy utilization ratio of drying process varied from 0.16 to 3.48 kJ/s and 0.065 to 0.572, respectively, while the exergy efficiency varied from 8.04% to 84.66%. The strategy of moisturizing for 30 min reduced 23.4% total energy utilization compared to continuous dehumidifying strategy. Both the highest average energy utilization ratio, i.e. 0.156 and average exergy efficiency, i.e. 70.19% were obtained for moisturizing time of 30 min. The increase of moisturizing time from 30 to 45 min showed an adverse impact on drying time, energy utilization ratio, exergy loss, and exergy efficiency due to the inhibition of water evaporation. This study shows that moisturizing strategy can be considered as a promising method to enhance energy and exergy efficiency of hot air dryer with the improvement of products quality and sustainability of drying systems. [Display omitted] • Moisturizing strategy was proposed for convective drying of mushroom slices. • The strategy of moisturizing for 30 min resulted in the shortest drying time. • The strategy of moisturizing for 30 min consumed the lowest energy. • Moisturizing strategy improved the quality of dried products. • The strategy of moisturizing for 30 min obtained the highest exergy efficiency. [ABSTRACT FROM AUTHOR]

Low-moisture foods (LMFs) are generally considered "lower risk" in terms of food safety, however, the frequent foodborne illnesses involved in the consumption of LMFs has heightened the public concern. The low a w environments also offer considerable protection against microorganisms. Meanwhile, the relatively high contamination risk of mycotoxins in low-moisture foods is a challenge for the food industry. Thermal decontamination techniques usually destroy heat-sensitive nutrients and lower product quality, and they are not adequate for mycotoxins detoxification. Therefore, developing non-thermal decontamination technologies to improve the safety of LMFs is of great interest in both of economics and public health. This review discusses the effects of non-thermal decontamination technologies, including ultraviolet and pulsed light, ionizing irradiation, cold plasma, and ozone, on microbial population and mycotoxin contents on LMFs. Furthermore, the working principles, applications, factors affecting processing efficacy and limitations of these decontamination technologies are summarized. The further research opportunities in commercialization are identified and discussed. Non-thermal decontamination technologies like UV and pulsed light, ionizing irradiation, cold plasma, and ozone have high potential as promising technologies for microbial inactivation and mycotoxin degradation for improving the safety and quality of LMFs. The operating conditions of the treatment, food property, species of microorganisms and mycotoxins are the major determinants affecting the processing efficacy. Further studies are recommended to evaluate the degradant toxicology and its interaction with food components, and particularly scaling-up the technology for commercial applications should be given more attention. Image 1 • Microorganisms and mycotoxins are frequently detected in low-moisture foods. • Non-thermal technologies have been emerged for promisingly improving the safety and quality of foods. • Pulsed light has higher decontamination efficiency than UV light. • Ionizing irradiation and ozone have been widely used for microorganism and mycotoxin decontamination. • Cold plasma processing is a promising decontamination strategy of microorganism and mycotoxin. [ABSTRACT FROM AUTHOR]

[Display omitted] • Electrohydrodynamic (EHD) drying was suitable for the dehydration of citrus peel. • Electric field type (AC vs. DC) affected drying characteristics and physicochemical quality. • Applied voltages led to different EHD drying behaviors and quality attributes of citrus peel. • EHD drying significantly affected the phytochemical components and volatile profiles. Based on the concept of circular economy, citrus peel was considered a valuable source of bioactive compounds for high-value foods. Electrohydrodynamic (EHD) drying is a novel technology appropriated for the dehydration of heat-sensitive products such as citrus peel. In current work, EHD drying of citrus peel was performed based on alternating current (AC) or direct current (DC) sources at various voltage levels (9, 18, 27, 36, and 45 kV). The effect of EHD on drying characteristics, water retention capacity, enzyme inactivation, phytochemical contents (phenolic compounds and carotenoids), and volatile compounds of citrus peel were evaluated and compared. Results showed that the drying time in the AC electric field was shorter compared to DC electric field at the same applied voltages due to the polarization layer formed by unipolar charges. The applied voltage determined electric field strength as well as the degree of tissue collapse and cell membrane rupture. EHD elucidated the transformation and degradation of phytochemicals including phenolic compounds, carotenoids, and volatile composition in proportion to the applied voltage. The findings indicate that EHD drying with AC improves drying behaviors, inactivates enzymes, and retains the phytochemical properties of citrus peel. [ABSTRACT FROM AUTHOR]

Abstract Effects of high-humidity hot air impingement blanching (HHAIB) on peroxidase (POD) and polyphenol oxidase (PPO) activities, ultrastructure, water distribution, drying time, and key quality attributes of apricots were investigated under air temperature of 110 °C and relative humidity of 35%–40% for various exposure times ranging from 30 to 150 s. HHAIB inactivated POD and PPO fully within 120 s, induced alteration of cellular structure and resulted in redistribution of water among the cell compartments. Compared to the untreated sample, HHAIB reduced the drying time by 19.36%–36.40%. Optimal pretreatment (120 s) resulted in dried apricots with higher total phenolics (TP) and total carotenoids (TC) along with enhanced antioxidant capacity, as well as better color. The TP, TC and antioxidant capacity were observed to be significantly correlated to POD and PPO activities, water distribution and drying time. Over-blanching (150 s) prolonged drying time, induced higher degradation of TP, TC, antioxidant capacity and color compared to dried products pre-blanched for 120 s. Hence, proper HHAIB pretreatment enhances drying process and improves the quality attributes of dried apricots. Graphical abstract Image 1 Highlights • High-humidity hot air impingement blanching improved the quality of dried apricots. • The blanching efficiently denatured PPO and POD, and reduced drying time of apricots. • The blanching induced cellular structure alteration and water redistribution. [ABSTRACT FROM AUTHOR]

Abstract Chili pepper is difficult to dry as the outermost surface is covered with an epicuticular wax layer, which hinders moisture transfer. Chemical dipping pretreatments and thermal blanching methods are often employed to enhance its drying process. However, chemical pretreatments hold the issues of chemical additives residue and thermal blanching methods tend to result in a high loss of bioactive compounds. Cold plasma is an ionized gas that contains different electrons, ions, and reactive neutral species. In current work, the feasibility of cold plasma as a non-thermal pretreatment technology for chili pepper drying is explored. The effects of different cold plasma pretreatment time (15, 30, 45, 60 s) on hot air drying kinetics and quality attributes of chili pepper, such as colour, red pigment retention, antioxidant activity, and microstructure were investigated. Results indicate that cold plasma can enhance the drying rate and the exposure time of 30 s achieves the optimum result. Microstructure observations show the existence of micro-holes, which explain how plasma treatment can enhance the drying kinetics. Quality attributes showed that the colour parameters had no significant changes under various treatment times. The retention of red pigment content was improved by plasma treatment of 30 s, whereas longer exposure times had a negative effect. The antioxidant activity of samples increased with the increase of cold plasma exposure time. Results indicate that cold plasma is a promising pretreatment technology for chili peppers as it enhances drying kinetics and quality attributes of chili pepper. Highlights • Cold plasma effectively enhances drying process of chili peppers. • Pigment extraction was improved for cold plasma exposure time up to 30 s. • Micro-holes generated in surface of pretreated chili pepper. • Colour profile had no significant changes under various treatment times. • Antioxidant activity increased with increase of cold plasma exposure time. [ABSTRACT FROM AUTHOR]

The effects of high humidity hot air impingement blanching (HHAIB) over a range of application times (30, 60, 90, and 120 s) on drying characteristics, hardness, cell wall pectin fractions contents and nanostructure, as well ultrastructure of apricot were investigated. Results showed that HHAIB reduced drying time and decreased the hardness of apricot by 20.7%–34.5% and 46.57%–71.89%, respectively. The water-soluble pectin (WSP) contents increased after blanching, while the contents of chelate-soluble pectin (CSP) and sodium-carbonate-soluble pectin (NSP) decreased significantly ( P  < 0.05). The hardness and drying time were found to correlate inversely with the WSP content, but positively with CSP and NSP contents. Atomic force microscopy (AFM) detection showed the decomposition and degradation of pectin fractions during blanching. Additionally, transmission electron microscopy (TEM) observation indicated that the cell wall structure was degraded and middle lamella integrity was destroyed by blanching. [ABSTRACT FROM AUTHOR]

Effect of high-humidity hot air impingement blanching on photochemical degradation kinetics (red pigments and ascorbic acid) and antioxidant capacity changes (2,2-diphenyl-1-picrylhydracyl, DPPH and total antioxidant capacity) of red pepper during 6-month storage at ambient temperature in dark was investigated. Ultrastructure of raw and blanched samples was also observed using a transmission electron microscope (TEM). Blanching followed by drying resulted in 63–85% and 33–59% reduction in red pigment and ascorbic acid content, respectively. The antioxidant capacity of samples was found to increase after drying. After 6-month storage, further breakdown of red pigment and ascorbic acid was observed. The red pigment degradation followed the first-order reaction kinetics; untreated samples displayed the most red pigment loss, while the Weibull model described well the ascorbic acid degradation kinetics. Ultrastructure observations explained why over-blanching can cause serious phytochemical degradation. The current findings indicate proper blanching pretreatment prevents phytochemicals degradation of dried pepper during storage. [ABSTRACT FROM AUTHOR]