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关键词： Food waste recycling   citrus waste   pyrolysis   biochar   sandy soil   water retention  

摘要： The citrus industry is considered one of the main contributors to agricultural waste. Peels are commonly used in the food industry or as feedstock in biorefining. In this study, the potential of waste orange peel biochar for agricultural applications in sandy soil was investigated. This will not only increase the percentage of agricultural waste recycling, but also lead to more sustainable agriculture with environmental benefits such as carbon sequestration. Biochar was produced through slow pyrolysis in the temperature range 300-600 degrees C and at two holding durations (10 min and 60 min). Both factors had a significant impact on the physicochemical characteristics of biochar in the heating region 300-450 degrees C. However, varying the holding time for pyrolysis temperatures beyond 450 degrees C had a diminishing effect on biochar properties compared with the impact of increasing pyrolysis temperature. The study also looked at certain properties that are specific to agricultural application not previously reported for orange peel. Very high cation exchange capacities of 70 cmol kg(-1) were achieved at 300 degrees C, whereas water holding capacity was not strongly influenced by pyrolysis conditions. Preliminary planting tests indicate potential for improving agricultural sustainability in sandy soils. The technoeconomic analysis of biochar showed that the pyrolysis process can be profitable with sufficient plant capacity.

ISBN: (纸本)9787122392367

关键词： Fires  

摘要： The physicochemical characteristics and chemical safety of two categories of grilled meat from Niger were assessed, using sun drying and optionally wood fire grilling processes. Contamination factors associated with the critical unit operations were identified and the technological parameters were monitored through these processes. Sixty samples were analyzed for dry matter, pH, and water activity. Polycyclic aromatic hydrocarbons were assessed using HPLC-FLD technique. No effect of the process on the duration of kilichi production was observed, whereas the yield of kilichi was significantly (p = .015) dependent on the process and kilichi category. Production of kilichi leads to losses of dry matter (yield <90%). All wood fire grilled samples were highly contaminated with BaP and PAH4, with concentrations exceeding up to 10 times the EU maximum limits set at 2 and 12 mu g/kg, respectively. Kiln type, fire wood species, and processing practices were the critical factors for an improved quality of kilichi. Novelty impact statement The two main traditional processes of grilled meat production identified in Niger are characterized for one process, by sun drying and wood fire grilling of beef meat and for the second process by sun drying only, without wood fire grilling. Grilled meat obtained through the process not involving wood fire grilling has a level of PAHs contamination lower than the maximal limits for BaP (2 mu g/kg) and PAH4 (12 mu g/kg), whatever the category of grilled meat. All the wood fire grilled meat samples are highly contaminated with BaP and PAH4, exceeding up to 10 times the EU maximum limits for both BaP and PAH4.

关键词： alternate wetting and drying   AWD   chalkiness   grain quality   rice functional properties  

摘要： Background and objectives Declining irrigation resources and warming cropping seasons present challenges to rice production. The alternate wetting and drying (AWD) management system conserve water, but its impact on rice grain quality is not well understood. To determine the effects of AWD irrigation management and varying seasonal temperatures on rice grain quality, a field experiment with two AWD irrigation methods and continuous flood (CF), as a control, was conducted in one year. Two environmental temperatures were observed as a result of two plating dates, one month apart. Findings Results revealed that AWD relative to CF, at either planting date, had minimum effect on grain quality traits of seven US varieties having diverse physicochemical and functional properties. On the other hand, mild warmer air temperatures that occurred during the grainfill period of the first planting were associated with lower head rice yield and higher chalkiness in brown and milled rice of some US varieties. The functional traits of apparent amylose content of low amylose varieties, Tp of a high gelatinization temperature variety, and total carbon were sensitive to air temperature changes during grain development. Conclusions AWD had no significant impact on rice grain quality, while some US varieties were more resilient to warmer temperature during grainfill on milling yield, chalk, and functional traits. Significance and novelty This study demonstrated that rice varieties can withstand moderate soil moisture stress from AWD management with minimum negative effects on grain appearance traits and functional properties.

关键词： storage quark cheese   transglutaminase   lipase  

摘要： In this study, the addition of microbial & nbsp;transglutaminase & nbsp;(MTG) and & nbsp;lipase & nbsp;in quark cheese samples was studied during storage (21 d). Four types of cheese were made using 3 different levels of MTG (T1, 0.1 g/L;T2, 0.2 g/L;T3, 0.3 g/L) and lipase (T1, 0.02 g/L;T2, 0.04 g/L;T3, 0.06 g/L), and one cheese was made without any treatment as a control sample. The physicochemical, textural, microbial, and & nbsp;sensory properties & nbsp;of cheese samples were monitored at 1, 7, 14, and 21 d of storage period. The results showed that the treated samples had higher & nbsp;proteolysis & nbsp;and & nbsp;lipolysis & nbsp;activities during storage than the control sample. The textural analysis indicated an insignificant increase in the hardness value of the enzyme-treated sample. Also, the sensory analysis exhibited that the treated samples had higher texture acceptability. The higher concentration of enzymes resulted in lower color, odor, taste, and overall acceptability, and higher microbial population. Finally, the addition of microbial MTG and lipase in preparation of quark cheese samples could be recommended for a short storage time.

关键词： detoxification   aflatoxins   Zea mays   corn grains   Aspergillus  

摘要： BACKGROUND Corn grains are commonly contaminated with mycotoxins and fungi. The purpose of this study was to evaluate the reduction of aflatoxins B-1, B-2, G(1), and G(2) and the inhibition of Aspergillus niger in corn grains using ultrasound, ultraviolet (UV) radiation, electrolyzed water, and sodium bicarbonate. The determination of aflatoxins was performed by high-performance liquid chromatography with fluorescence detection and postcolumn derivatization, and analysis of A. niger was performed by evaluating mycelial growth in potato dextrose agar. The best treatment for reducing aflatoxins and inhibiting mycelial growth was evaluated in corn contaminated with A. niger. RESULTS The results show a significant reduction in aflatoxins in the following order: sodium bicarbonate > ultrasound > UV > electrolyzed water for aflatoxins B-1, B-2, and G(2). For aflatoxin G(1), the order of reduction was sodium bicarbonate > ultrasound > electrolyzed water > UV, with maximum values between 70.50% and 87.03% reached with sodium bicarbonate;for the other treatments, the reduction was between 51.51% and 65.44%. Regarding the fungus, the order of inhibition in the control of mycelial growth was sodium bicarbonate > ultrasound > electrolyzed water > UV in corn grains, and inhibition of mycelial growth was obtained at a sodium bicarbonate concentration of 3.0 g L-1. CONCLUSION Sodium bicarbonate, electrolyzed water, ultrasound, and UV radiation inhibited the growth of A. niger on potato dextrose agar and reduced the contents of aflatoxins B-1, B-2, G(1), and G(2) in vitro. Sodium bicarbonate showed an ability to inhibit mycelial growth in corn grains. (c) 2020 Society of Chemical Industry

关键词： Chitosan   beta-Acids   Physicochemical property   Antibacterial   Release modeling  

摘要： beta-Acids are natural antibacterial and antioxidant ingredients, obtained from supercritical CO2 hop extract. In this study, beta-acids/chitosan complex films were prepared using the casting method. Complex films were characterized using scanning electron microscopy (SEM), atomic force microscope (AFM), Fourier transform infrared spectroscopy (FTIR), and X-ray diffraction analysis (XRD). Structure analysis revealed that beta-acids can be successfully combined with the chitosan matrix. Mechanical tests demonstrated that the tensile strength of the films showed a significant upward trend (1.9 MPa to 9.6 MPa) with increase in beta-acids content (0.1%-03%). Interestingly, the chitosan-based films showed excellent UV barrier capability below 400 nm. The release of beta-acids from the film followed Fickian diffusion (n < 0.45). In addition, the complex films inhibited the growth of five food-borne pathogens (Escherichia coli, Staphylococcus aureus, Bacillus subtilis, Salmonella enteritidis and Listeria mortocytogenes). This study highlights the promising nature of composite film as a desirable alternative for active packaging. (C) 2021 Elsevier B.V. All rights reserved.

关键词： Functional properties   Hydrocolloid   Starch  

摘要： In this paper, the impact of different substitution levels of cress seed gum (CSG, 0, 5, 10, and 15%) and sucrose (SUC, 0, 5, and 10%) on the rheological properties, textural attributes, syneresis, FTIR and microstructure of native wheat starch (NWS, 4%) gel was investigated. According to the rheological tests, the NWS-CSG and NWS-CSGSUC gels showed thixotropic behavior and all the samples exhibited shear-thinning flow behavior. Increasing the CSG substitution level up to 15% elevated the apparent viscosity, consistency coefficient whereas the SUC substitution with NWS reduced these values. The higher apparent viscosity, consistency coefficient, and stronger pseudoplastic behavior were obtained for NWS-CSG-SUC gel than NWS gel. The addition of CSG greatly decreased hardness and consistency from 140 to 55.5 g and from 6.9 to 3.0 mJ, respectively during storage at 4 degrees C for 14 days;while in the presence of SUC these values slightly decreased. After storage, syneresis of NWS and NWS10%SUC gels increased by 46.78% and 32.11%, respectively;whereas it decreased 19.88% for NWS-15%CSG gel. The SEM images showed that the mixed gels had a denser structure with a smaller pore size. The results indicated that CSG had positive effect in modifying the properties of NWS-SUC mixed gels. (c) 2021 Elsevier B.V. All rights reserved.

关键词： Potato steamed bread   Wheat steamed bread   Saprophytic microorganisms   Flavor compounds   Electronic nose and tongue   Storage properties  

摘要： Due to its nutritional value and no gluten, potato flour has recently been used as a new type of material to make steamed bread. However, compared to traditional wheat steamed bread, its shelf life is considerably shorter, the dominant microorganisms and storage properties also differ. High-throughput sequencing combined with molecular biology assay revealed that Bacillus methylotrophic and Bacillus subtilis were the dominant bacteria in the crumb of potato and wheat steamed bread, respectively. Moreover, Meyerozyma, Penicillium chrysogenum, Penicillium citrinum, and Aspergillus parasiticus were the main fungi in the crusts. Ethanol was the most volatile compound in fresh potato and wheat steamed bread. Following storage for 48 h, 2,3-butanediol and 3-hydroxy-2butanone were established as the most volatile compounds. Although decreased sourness was observed, the specific volume, brightness, and nutritional composition remained nearly unchanged. These findings provide a valuable theoretical basis for the development of potato and wheat steamed bread preservation technologies.

关键词： Heartwood   sapwood   lignin   phenolic hydroxyl groups   dielectric permittivity  

摘要： Lignin polymers are among the main components of the cell wall and characterized by the highest reactivity due to their polyfunctional nature, the presence of reactive centers and a conjugated polymolecular aromatic structure. Investigation of differences in functional composition, macromolecular, reaction and electrophysical properties of slightly altered preparations of dioxane lignin extracted from the heartwood and sapwood of pine was carried out in this paper. The increased content of carboxyl groups in the heartwood lignins leads to a decrease in the reaction (acid-base and redox) properties and specific electrical conductivity. Changes in the physicochemical properties of lignins in the wood matrix indicate the continuous transformation of the natural polymer during the life cycle of plants.