Soybean Curd Residue Research Articles

Additives improve the fermentation quality, anthocyanin content, and biological activity of purple Napier grass silage.

Purple Napier grass (PNG), a widely used grass rich in anthocyanin, is commonly employed in the production of silage. However, there is currently limited research on the retention of anthocyanin with or without additives during ensiling. Therefore, this study aimed to investigate the effect of different additives (Lactiplantibacillus plantarum CCZZ1 (LP), glucose, acetic acid, and dried soybean curd residue) on fermentation quality, anthocyanin content, and microbial community structure of PNG silage. Ensiling PNG without additives led to poor fermentation quality and rapid degradation of anthocyanin, resulting in a decline in antioxidant activity and the persistence of harmful microorganisms with high relative abundance. The use of additives, especially LP, effectively increased the relative abundance of L. plantarum, enhancing fermentation quality, the retention of anthocyanin (up to 166% increase rate) and antioxidant activity, while reducing the relative abundance of harmful microorganisms during ensiling for 30 days. Additionally, prolonged ensiling negatively affected the preservation of anthocyanin. Based on both fermentation quality and bioactivity, PNG should be ensiled for 30 days with LP inoculation. The employment of additives, especially LP, improved the fermentation quality, anthocyanin retention, and microbial community structure in PNG silage. To optimize both fermentation quality and bioactivity, it is recommended that PNG be ensiled for 30 days with LP inoculation. © 2024 Society of Chemical Industry.

The potential of soybean curd residue and water fraction of dragon fruit peel in wet noodles formulation

The potential of agro-industrial by-products in food products development have been reported for their nutritional composition. Soybean curd residue (okara flour - OF) and dragon fruit peels (DFP) have been known as a source of protein, fiber, and antioxidant compounds. Their potential in wet noodle formulation has never been investigated. The study aimed to investigate the potential of soybean curd residue, OF, and water fraction of DFP in wet noodles formulation. Four different levels of OF (0, 10, 20, and 30 %) and four different levels of DFP (0, 7, 9, and 11 %) was incorporated in wheat-based wet noodles. Physicochemical properties, sensory acceptability and antioxidant properties were investigated. The study showed that most impact was given by different levels of OF. The higher level of OF declined the moisture content and protein content significantly (p < 0.05) from a range of 45–48 % to the lowest level at 31 % and from 6.7–8 % to 5 %, respectively. The ash content increased as the level of OF was higher from 0.27 % to the highest level at 0.63 %. All the formulated noodles had a desirable value of cooking loss (<10 %) although it increased from 6 % in control to 9 % in 30 % OF addition. Hedonic sensory acceptability revealed that up to 20 % OF addition generated the same level of acceptability as it was in control showing and the incorporation of 9 % DFP to the 20 % of OF addition had the highest score of sensory acceptability. Antioxidant activity revealed that the selected formula (20 % OF and 9 % DFP) had higher antioxidant capability against DPPH shown by the lower level of IC50. In conclusion, combination of OF and DFP can be expected as sustainable food ingredients in wet noodles formulation.

Cultivating black soldier fly (Hermetia illucens) larvae on coconut endosperm and soybean curd residue: Impact on growth performance, waste reduction efficiency and larval nutritional composition

AbstractBlack soldier fly larva (BSFL), Hermetia illucens (L.) (Diptera: Stratiomyidae), presents an attractive waste management solution that not only addresses the issue of waste but also generates alternative proteins and fats. Substrate quality and pre‐treatment by fermentation may play a crucial role in waste reduction efficiency and larval quality. The aim of this study was to investigate the growth performance, waste reduction efficiency and nutritional composition of BSFL rearing using different ratios of coconut endosperm (CE) and soybean curd residue (SC) with pre‐treatment by self‐fermentation (F), fermentation with baker's yeast (Y) and without pre‐treatment (C). Seven‐day‐old larvae were randomly separated into 15 experimental groups with three replicates. The experiment ended when the prepupae appeared. Based on the results, the larvae fed a diet with a high percentage of fresh SC exhibited the highest weight and growth rate, whereas the shortest development time was observed in larvae reared on Y. Pre‐treatment of the substrate with fermentation proved effective in waste reduction. The nutritional composition of the larvae showed that the highest crude protein was produced in larva reared on fresh 100% SC, and the highest ether extract was found when fed CE at 100% with pre‐treatment with F or Y. In conclusion, it is recommended to employ a fresh diet with a high SC content to optimise protein production, whereas a high level of CE with F or Y may be performed to obtain a high ether extract content. However, incorporating yeast fermentation with an SC content exceeding 25% provided high efficiency in waste reduction. Therefore, the selection of the ratio between CE and SC and of pre‐treatment techniques depends on the producer's objective.

Quality characteristics and volatile compounds of plant-based patties supplemented with biji powder

Biji (okara or soybean curd residue), a by-product of soybean processing, contains proteins. In this study, control plant-based patties were compared with patties supplemented with biji powder (5, 10, 15, and 20 g). Increasing the amount of biji added to patties was found to be favorably associated with increased water-holding capacity, decreased cooking loss, and reduced diameter and thickness. Texture profile analysis revealed trends of increased hardness, springiness, cohesiveness, and chewiness which were proportional to the inclusion of biji powder. The volatile compounds in plant-based patties supplemented with biji were analyzed using HS-SPME-Arrow-GC/MS. Notably, benzaldehyde, nonanal, and 2-heptanone, which are undesirable flavors, were detected at significantly lower levels in patties supplemented with biji. Therefore, biji can serve as a supplementary ingredient to enhance the texture and flavor of plant-based patties.

Larval biomass production from the co-digestion of mushroom root waste and soybean curd residues by black soldier fly larvae (Hermetia illucens L.).

People are increasingly using black soldier fly larvae (BSFL) as a sustainable waste management solution. They are high in protein and other essential nutrients, making them an ideal food source for livestock, poultry, and fish. Prior laboratory studies with BSFL developed on pure mushroom root waste (MRW) showed poor conversion efficiency compared to a regular artificial diet. Therefore, we mixed the nutrient-rich soybean curd residues (SCR) with MRW in different ratios (M2-M5). Pure mushroom root waste (M1, MRW 100%) had the lowest survival rate (86.2%), but it increased up to 96.9% with the SCR percentage increasing. M1 had the longest developmental period (31.1days) and the lowest BSFL weight (7.4g). However, the addition of SCR reduced the development time to 22.0 and 21.5days in M4 (MRW 40%, SCR 60%) and M5 (MRW 20%, SCR 80%), respectively, and improved the larval weight to 10.9g in M4 and 11.8g in M5. Other groups did not have as much feed conversion ratio (FCR) (8.4 for M4 and M5), bioconversion (M4 5.4%; M5 5.9%), or lipid content (M4 25.2%; M5 24.3%). These mixtures did.Compare this to M1. We observed better results, with no significant differences between the M4 and M5 groups and their parameters. In the present study, our main target was to utilize more MRW. Therefore, we preferred the M4 group in our nutritional and safety investigation and further compared it with the artificial diet (M7). The heavy metals and essential amino acids (histidine 3.6%, methionine 2.7%, and threonine 3.8%) required for human consumption compared to WHO/FAO levels showed satisfactory levels. Furthermore, fatty acids (capric acid 1.9%, palmitic acid 15.3%, oleic acid 17.3%, and arachidonic acid 0.3%) also showed higher levels in M4 than M7. The SEM images and FT-IR spectra from the residues showed that the BSFL in group M4 changed the structure of the compact fiber to crack and remove fibers, which made the co-conversion mixture better.

Anti-Diabetic Effect of Okara Noodles on Streptozotocin-Nicotinamide Induced Diabetic Rats

Okara is a by-product of soybean curd residue resulting from the processing of soy milk and tofu. Okara noodles were made from wheat flour (WF) and okara flour (OF) with a few modifications that consist of high dietary fiber. Therefore, okara can be considered as an effective functional component with health-promoting benefits, especially for diabetes mellitus. Albeit, the anti-diabetic effect has not been conscientiously investigated. The goal of the current research was to evaluate the anti-diabetic effect of okara noodles on Streptozotocin-Nicotinamide induced diabetes mellitus rats. In the experiment, the different ratios of OF was used to prepared 3 formulated noodles (F0, F1 and F2) where F0 (0 % OF; 100 % WF), F1 (25 % OF; 75 % WF) and F2 (45 % OF; 55 % WF). Twenty-four male wistar rats were randomly divided into 4 groups (6 rats/groups), normal group of rats fed with standard feed and 3 diabetics groups, respectively fed with standard feed and formulated noodles variety (F0, F1 and F2). In in vivo analysis, it indicated, diabetes mellitus rats fed okara noodles had lower blood glucose levels and HOMA-IR and higher serum insulin levels and HOMA-b index than those fed control noodles (F0) as well as body weight managing activity. These outcomes demonstrated okara noodles possess significant anti-diabetic activity, prompting the applicability of okara noodles as potential food for the diabetes mellitus food products. HIGHLIGHTS Diabetes mellitus (DM) rats fed okara noodles had lower BGLs and HOMA-IR DM rats fed okara noodles had higher serum insulin levels and HOMA-b index than those fed control noodles as well as body weight managing activity Okara can be considered as an effective functional component for the anti-diabetic effect on STZ-NA induced DM rats GRAPHICAL ABSTRACT

Green synthesis of highly pyrrolic nitrogen-doped biochar for enhanced tetracycline degradation: New insights from endogenous mineral components and organic nitrogen synergy

The synthesis of efficient and environmentally friendly persulfate (PS) catalysts is currently a prominent research focus. This study employs single-step carbonization to investigate the interactions between endogenous mineral components (EMCs) and N-doping of nitrogen-rich biomass, aiming to design efficient biochar-based catalysts for enhanced tetracycline (TC) degradation. Biochars (PBC and SBC) derived from peanut hulls (PH) and soybean curd residue (SCR) with similar EMCs (ash ratio 16:19) but varying nitrogen content (1 % vs 1.53 %) were achieved, along with melamine-N-doped PBC (PBCN) for comparison under identical conditions. Physicochemical and quantum-chemistry analyses were conducted to investigate the synergistic effects between EMCs and organic-nitrogen in terms of morphological structures, active sites, and catalytic persulfate (PS)-mediated degradation of TC. The findings revealed that the optimal synthesis temperature for the efficient biochar-based catalyst was 800 °C. In contrast to exogenous N-doping with higher N-content (7.81 %), organic-N accelerated lattice disruption, leading to enhanced interactions with EMCs and resulting in the formation of hierarchical structures and pyrrole-N (organic-N 43.44 % > exogenous-N 17.67 %). The SBC/PS system exhibited superior degradation capability, with rapid removal of 95 % in 100 mg·L-1 TC. Density functional theory (DFT) confirmed that the non-radical pathways including 1O2 and electron transfer, facilitated by the presence of CO and pyrrole-N, were responsible for binding PS and forming biochar-PS*. This study furnishes both experimental data and theoretical insights, supporting the targeted control and efficient advancement of eco-friendly, high-value biochar-based catalysts.

Upcycling of food waste generated from the fresh market by utilising black soldier fly larvae: Influence on growth, bioconversion, and nutritional composition

Innovative solutions are needed to limit environmental effect and optimise resource use as food waste generation rises worldwide. This study investigates the potential of upcycling food waste from fresh markets using Black Soldier Fly (Hermetia illucens) larvae (BSFL) as a sustainable approach. This study explored four fresh market food waste substrates for BSFL bioconversion: discarded fish waste (FI), slaughtered chicken waste (CHI), vegetable waste (VEG), and a 1:1:1 combination of all three (MIX). Soybean curd residue (SCR) was treated as the control substrate. The effects on larval growth, nutritional content, and waste bioconversion rates were examined. The larvae growth rate was strongly impacted by waste type, with BSF-fed CHI and MIX gaining 18.0 and 16.7 mg/d, respectively, followed by BSF-fed with SCR (12.2 mg/d), FI (8.9 mg/d) and VEG (7.6 mg/d). The waste type did not substantially alter BSFL length. The survival rate of the BSFL fed with the food waste studied ranges from 95 to 98.47%, with SCR being the highest. Our findings indicated that BSFL can effectively convert a variety of fresh market food waste into valuable biomass. CHI waste produced the highest larval biomass and bioconversion rate followed by MIX, SCR, FI and VEG. The different waste stream has a major influence on BSFL biomass nutrition. BSFL nutritional composition is independent of the substrate’s nutritional content, indicating no direct correlation between substrate and BSFL biomass nutritional composition. SCR waste produced the highest protein content of BSFL (50.49%), followed by VEG (32.61%), MIX (32.57%), FI (31.03%) and CHI (29.06%). SCR waste also produced BSFL biomass with lowest lipid content (26.55%) compared to other waste which resulted into BSFL with lipid levels ranging from 42.92% to 53.72%. BSFL-fed with SCR is the most suitable to be used as an alternative animal’s feed based on the protein and lipid levels, while defatting procedure is necessary for the other waste-fed BSFL to render it suitability as animal feed alternatives. Based on bioconversion rate, BSFL growth, and lipid content, the MIX and CHI waste might be viable substrates for future research.

Zero Waste Technology of Soybeans Processing

Soybean can be easily digested and is a valuable substitute for animal protein in various applications. That is why soy products are a very important component of a vegan and vegetarian diet. During soymilk processing, large quantities of by-products are generated. Hardly anyone knows that every kilogram of dried soybeans processed into soymilk or tofu gives about 1.2 kg of soybean curd residue, namely, okara, often regarded as a waste. Acting in the spirit of zero waste, a soybean processing technology has been developed that does not generate waste. The developed technology consists of obtaining soymilk followed by filtration to remove the insoluble residues (okara), preparing okara and fermenting to obtain vegan soft cheese. Samples analyzed for physical, chemical, and organoleptic properties. Also, the microbial quality of the obtained products was tested. Soy products produced with the proposed zero waste technology were assessed by the sensory panel and received very good marks. Fermented soy products are characterized with high levels of Lactobacillus spp. (105–108 cfu/mL), thus consuming them can bring health benefits. Cheese made from okara can be an alternative to cheeses currently obtained from soymilk.

Improving the quality and reducing harmful microbes of total mixed ration silage with dried soybean curd residue

The production of safe and high-quality silage has always been the main concern. This experiment aimed to investigate the impact of waste dried soybean curd residue (SR) and Lactobacillus plantarum CCZZ1 on the fermentation quality and microbial community of total mixed ration (TMR) silage based on Napier grass (Pennisetum purpureum). Napier grass was made into TMR, and SR at 3%, 6% or 9% on dry material basis was included, which replaced the equivalent amount of corn meal, then they were inoculated without or with Lactobacillus plantarum CCZZ1 (105 cfu g−1; LP). The research results showed that incorporating SR even at 3% resulted in significant reduction in ammonia nitrogen content (87.3 g kg−1 total nitrogen vs. 109.7 g kg−1 total nitrogen), increased lactic acid content (34.4 g kg−1 DM vs. 25.5 g kg−1 DM), and higher relative abundance of Lactobacillus (94.5% vs. 32.2%). Additionally, it led to decreased relative abundances of pathogenic microorganisms such as Escherichia coli (< 0.1% vs. 9.68%), Staphylococcus epidermidis (< 0.1% vs. 9.46%), and Streptococcus pneumoniae (< 0.1% vs. 8.53%) during the ensiling process. When SR was used together with LP inoculation, they were further improved. These findings suggest that the inclusion of SR, even at a 3% level without LP inoculation, can effectively improve the fermentation quality and microbial profile of TMR silage based on fresh Napier grass. This offers a promising technical approach to utilizing SR and producing safe and high-quality TMR silage based on fresh grass.Graphical

Incorporation of soybean curd residue (okara) and its effects on nutritional and organoleptic properties of cassava crisp (opak) for healthy snacking

Soybean curd residue (SCR) or okara is a by-product generated during the production of soy milk or tofu. It contains high dietary fiber and protein that are beneficial for the maintenance of normal bowel function and also for building and repairing body tissues. However, it is used as stock feed and fertilizer or dumped in landfills. Therefore, this study was conducted to incorporate the SCR into traditional cassava crisp (opak) to produce healthier snacks and add value to this nutritious waste. Thirteen formulations with different proportions of grated cassava/SCR powder/tapioca flour were generated by Doptimal Mixture Design. Dietary fiber, protein content and sensory scores were the responses. Higher proportions of SCR increased the protein and dietary fiber content but decreased the organoleptic scores. Thus, the optimum formulation (85% grated cassava, 6% SCR powder and 6% tapioca flour) was selected for the high dietary fiber content and the highest scores of sensory properties (taste, texture and overall acceptability). Incorporation of the SCR powder in the final product enhanced the dietary fiber and protein content of the traditional opak and reduced the fat content by approximately three, six and 1.5 times. Hence, this improved formulation of opak will be a better choice for consumers for their healthier snacking.

Two-stage preparation of highly mesoporous carbon for super-adsorption of paracetamol and tetracycline in water: Important contribution of pore filling and π-π interaction

This study aimed to develop an extremely highly porous activated carbon derived from soybean curd residues (SCB-AC) through two-step pyrolyzing coupled with KOH activating process and then apply it for removing paracetamol (PRC) and tetracycline (TCH) from water. The optimal conditions for chemical activation were 800 °C and the ratio of KOH to material (4/1; wt./wt.). SCB-AC adsorbents (before and after adsorption) were characterized by Brunauer-Emmet-Teller (BET) analyser, Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy, and Raman spectroscopy. Adsorption kinetics, isotherm, and thermodynamics were concluded under batch experiments. The effects of pH (2–10) and NaCl (0–1 M) on adsorption processes were investigated. Reusable properties of laden SCB-AC were evaluated by studying desorption and cycles of adsorption/desorption. Results indicated that SCB-AC exhibited a large specific surface area (3306 m2/g) and high total pore volume (2.307 cm3/g), with mesoporous volume accounting for 86.9%. Its porosity characteristics (average pore width: 2.725 nm) are very appropriate for adsorbing two pharmaceuticals through pore-filling mechanism. Adsorption processes were less affected by the parameters: pH, NaCl, and water matrixes. The kinetics for adsorbing PRC reached a faster equilibrium than that for TCH. The Langmuir maximum adsorption capacity of SCB-AC (pHeq 7.0 and 25 °C) was 1235 mg/g (for adsorbing TCH) and 646 mg/g (PRC). Pore filling (confirmed by BET analyser) and π-π interaction (confirmed by FTIR and Raman spectroscopy) were dominant adsorption mechanisms. Those mechanisms were physisorption (ΔH° = 13.71 and −21.04 kJ/mol for adsorbing TCH and PRC, respectively). SCB-AC can serve as an outstanding material for removing pharmaceuticals from water.

Bioconversion of Desiccated Coconut and Soybean Curd Residues for Enhanced Black Soldier Fly Larvae Biomass as a Circular Bioeconomy Approach

Bioconversion of Desiccated Coconut and Soybean Curd Residues for Enhanced Black Soldier Fly Larvae Biomass as a Circular Bioeconomy Approach

Food waste and soybean curd residue composting by black soldier fly

This study attempted to manage the food waste and soybean curd residue generated in Taiwan's National Ilan University by black soldier fly-aided co-composting. The food waste and soybean curd residue were co-composted with rice husk as a bulking agent in 4:1 ratio and 0.42 mg BSF/g waste. The higher organic matter degradation of 31.9% was found in Container B (black soldier flies aided food waste and rice husk co-composting) with a rate constant of 0.14 d−1. In Container D (black soldier flies aided soybean curd residue and rice husk co-composting), the organic matter degradation of 29.4% was found with a rate constant of 0.29 d−1. The matured compost of 6.02 kg was obtained from 20 kg of food waste, while 5.83 kg of matured compost was generated from 20 kg of soybean curd residue. The physico-chemical parameters of the final matured compost were in the favorable range of Taiwan's compost standards. The germination index was 188.6% and 194.78% in Containers B and D, respectively. The present study will expand the application of BSF at the institutional level which prove to be a feasible solution for rapid, clean, and efficient composting of post-consumer food wastes.

Enhanced Adsorption of Carbon Dioxide by Phosphoric Acid-Modified Soybean Curd Residue Biochar

Enhanced Adsorption of Carbon Dioxide by Phosphoric Acid-Modified Soybean Curd Residue Biochar

Black soldier fly, Hermetia illucens as a potential innovative and environmentally friendly tool for organic waste management: A mini-review.

The application of black soldier fly (BSF), Hermetia illucens based technology to process organic wastes presents a practical option for organic waste management by producing feed materials (protein, fat), biodiesel, chitin and biofertilizer. Therefore, BSF organic wastes recycling is a sustainable and cost-effective process that promotes resource recovery, and generates valuable products, thereby creating new economic opportunities for the industrial sector and entrepreneurs. Specifically, we discussed the significance of BSF larvae (BSFL) in the recycling of biowaste. Despite the fact that BSFL may consume a variety of wastes materials, whereas, certain lignocellulosic wastes, such as dairy manure, are deficient in nutrients, which might slow BSFL development. The nutritional value of larval feeding substrates may be improved by mixing in nutrient-rich substrates like chicken manure or soybean curd residue, for instance. Similarly, microbial fermentation may be used to digest lignocellulosic waste, releasing nutrients that are needed for the BSFL. In this mini-review, a thorough discussion has been conducted on the various waste biodegraded by the BSFL, their co-digestion and microbial fermentation of BSFL substrate, as well as the prospective applications and safety of the possible by-products that may be generated at the completion of the treatment process. Furthermore, this study examines the present gaps and challenges on the direction to the efficient application of BSF for waste management and the commercialization of its by-products.

Effects of aeration rate and feed on growth, productivity and nutrient composition of black soldier fly (Hermetia illucens L.) larvae

Black soldier fly larvae (Hermetia illucens L.) are widely cultivated as bioconversion agents. These larvae are known to be highly sensitive to changes in the external environment, such as temperature and relative humidity. Therefore, a rearing hive equipped with an instrumentation system known as the Modular Fly Hive was designed to cultivate black soldier larvae. This study aimed to determine the effects of aeration rate (0 – 0.84 m3/s.) and feed type (coconut endosperm waste and soybean curd) on growth and productivity of black soldier fly cultivated in Modular Fly Hives as well as well as feed digestibility and nutrient composition of the larval biomass. Increasing aeration rate decreased the average temperature and relative humidity within the hives. The results showed that the larvae demonstrated a sigmoidal growth curve for all types of feed and the type of feed significantly affects the average wet weight and length of the larvae. The greatest dry biomass productivity (52.85 ± 3.85 g/m2/day) was observed when the larvae were cultivated using soybean curd residue with an aeration rate of 0.84 m3/s, while the lowest dry biomass productivity (35.27 ± 9.72 g/m2/day) was observed when the larvae were cultivated using coconut endosperm waste without aeration. Proximate analysis revealed that the larval biomass had total protein, lipid, ash and carbohydrate content in the range of 37.20 – 48.60%, 9.61 – 20.02%, 4.80 – 6.40%, 33.86 – 38.70%, respectively. Amino acid in the biomass were dominated by glutamic acid (11.11–12.30%), aspartic acid (8.25 – 10.35%), leucine (8.09 – 8.57%), and lysine (6.74 – 8.14%). Lipid isolated from the larval biomass were mainly composed of lauric acid (28.35–61.68%), linoleic acid (6.27 – 30.29%), palmitic acid (7.62 – 15.23%), and myristic acid (5.05 – 14.34%).

Fermentation Quality and Microbial Community of Corn Stover or Rice Straw Silage Mixed with Soybean Curd Residue.

Simple SummarySoybean curd residue (SCR) is a potential ruminant feed, offering a rich source of fiber, protein, and lipids. However, the excessively high water content of SCR may lead to difficulty in its storage. For ruminants, corn stover and rice straw are common sources of roughage, but these are often restricted because of their low digestibility. Mixed ensiling of SCR with corn stover (CS) or rice straw (RS) may provide a solution to the problem of the SCR being difficult to preserve. This study aimed to evaluate the chemical constituents, fermentation quality, and microbial community of CS or RS silage mixed with SCR. Such mixing with SCR increased the lactic acid and protein contents and decreased the pH value, the content of neutral detergent fiber (NDF) and acid detergent fiber (ADF), ammonia nitrogen concentration, and bacterial diversity in both CS and RS silage mixtures and improved their nutritional value and fermentation quality as well.The objective of this study was to investigate the fermentation quality and microbial community of corn stover (CS) or rice straw (RS) silage mixed with soybean curd residue (SCR). In this study, SCR and CS or RS were mixed at ratios of 75:25, 70:30, and 65:35, respectively, and measured for nutrient content, fermentation indices, and bacterial diversity after 30 days of ensiling. The results showed an increase in lactic acid (LA) concentration (p < 0.01) and crude protein (CP) content (p < 0.0001), a decrease in pH value (p < 0.01), the content of NDF (p < 0.01) and ADF (p < 0.01), and ammonia nitrogen (AN) concentration (p < 0.01) as the proportion of SCR in raw materials (CS or RS) increased. The addition of SCR to silage led to a decrease in bacterial diversity and contributed to an increased relative abundance of beneficial microorganisms, such as Lactobacillus, and a corresponding decrease in the relative abundance of undesirable microorganisms, such as Clostridium and Enterobacter. Collectively, the mixed silage of soybean curd residue with corn stover or rice straw preserved more nutrients and helped improve fermentation quality.

Conversion of Mixtures of Soybean Curd Residue and Kitchen Waste by Black Soldier Fly Larvae (Hermetia illucens L.).

Simple SummaryThe black soldier fly (BSF) is a viable solution for food waste management and can provide a sustainable protein source to feed the growing global population. However, the growth performance of BSF larvae (BSFL) is greatly influenced by the rearing substrate. An imbalanced diet caused by the utilization of single substrate could be solved using a mix of different waste types and formulating a more balanced diet, which would provide a more reasonable nutritious and balanced energy feed for larval growth. This study focused on the effects of different proportions of mixtures of soybean curd residue (SCR) and kitchen waste (KW) on the performance of BSFL. The key findings of this study are: the highest larval biomass (30.32 g fresh and 11.38 g dry mass), bioconversion rate (18.54%) and larval crude lipid (45.91%), and the lowest feed conversion ratio (FCR) (2.51) were obtained when BSFL were fed with 30% SCR and 70% KW.The production of insect biomass from organic waste is a major challenge in terms of reducing the environmental impacts of waste and maintaining feed and food security. The feasibility of the co-conversion of soybean curd residue (SCR) and kitchen waste (KW) to breed black soldier fly (BSF, Hermetia illucens) larvae was evaluated so as to enhance biomass conversion efficiency and supply animal feed and allow it to be used in biodiesel production. Co-digestion was found to significantly increase larval yield, bioconversion rate, and bioaccumulation of lipid. Partial least squares regression showed that the conversion of 30% SCR with 70% KW is an appropriate proportion. The appropriate performance parameters of BSF were: survival rate (98.75%), prepupal rate (88.61%), larval biomass (30.32 g fresh and 11.38 g dry mass), bioconversion rate (18.45%), efficiency conversion of ingested food (ECI) (28.30%), and FCR (2.51). Our results show that conversion of mixtures (e.g., SCR with KW) by BSF larvae (BSFL) could play an important role in various organic materials management.

Dried soybean curd residue: A promising absorbent for cleaner production of high-quality silage

In humid and rainy regions, such as tropical and subtropical areas, forage crops have a high moisture content and are difficult to wilt after harvest, which can easily cause poor fermentation and effluent production of silage. In the present study, the best product, with a high moisture-absorbing capacity (MAC) and stable structure, was selected from 12 types of agricultural and sideline products and the effects of its addition to high-moisture Napier grass (Pennisetum purpureum) silage at 0%, 3%, 6%, or 9% of fresh grass weight were studied. The results showed that dried soybean curd residue (SR) not only had the strongest MAC but also had the most stable structure at different pH levels. Adding SR even at 3% significantly improved fermentation quality and reduced protein degradation and effluent production (38.3 vs. 107.5 ml kg−1 FM) during ensiling compared with those in the control (P < 0.01). The effluent production of control silage significantly increased in the first 30 days of ensiling (P < 0.01) and, thereafter, did not increase (P > 0.05). The dry matter and crude protein losses from the effluent in the control silage significantly increased (P < 0.01) during early ensiling (3–15 d), and there were no significant changes (30–60 d, P > 0.05). The addition of 6% SR completely prevented the production of effluent from the silage. These results demonstrate that SR is a promising and efficient moisture absorbent for cleaner production of high-quality silages without effluent.