Tofu Whey Permeate Is an Efficient Source To Enzymatically Produce Prebiotic Fructooligosaccharides and Novel Fructosylated α-Galactosides

Tofu Whey Wastewater as a Beneficial Supplement to Poultry Farming: Improving Production Performance and Protecting against Salmonella Infection

Tofu whey wastewater (TWW) is a by-product of the tofu production process, and contains high amounts of organic products and Lactobacillus ap. However, no studies have been reported on whether naturally fermented TWW can be used as a beneficial additive for poultry production. This study analyzed the main nutritional components and microbial flora of naturally fermented TWW from rural tofu processing plants and their effect on chick production performance, role in modulating the biochemical and immune parameters, and protection against Salmonella enteritidis (S. enteritidis) infection. It was observed that the average pH of TWW was 4.08; therefore, the total viable count was 3.00 × 10⁹ CFU/mL and the abundance of Lactobacillus was 92.50%. Moreover, TWW supplementation increased the total weight gain and feed intake, reduced the feed/gain ratio, increased the length and relative weight of the gut, and reduced the colonization and excretion of S. enteritidis in chickens. Additionally, TWW decreased oxidative damage and pro-inflammatory cytokine secretion caused by S. enteritidis infection. In addition, TWW supplementation ensured the structure of the intestine remained relatively intact in S. enteritidis-infected chicken. Furthermore, TWW markedly promoted the intestinal barrier integrity and up-regulated the relative abundance of Lactobacillus, counteracting the changes in gut microbiota caused by S. enteritidis infection in chicken. In conclusion, our data demonstrated that TWW could be used as a beneficial addition to poultry production, providing a research basis for the further development of TWW as a health care application in in food-producing animal.

Development of an alternative medium via completely replaces the medium components by mixed wastewater and crude glycerol for efficient production of docosahexaenoic acid by Schizochytrium sp

Exorbitant substrates for Schizochytrium culture result in the high cost of docosahexaenoic acid (DHA) production. In order to develop a feasible approach that is expected to reduce DHA production cost, Schizochytrium sp. S31 cultivation with a mixture of saline wastewater (SWW) and tofu whey wastewater (TWW) was investigated in this study. Using glucose as the carbon source, the maximum biomass and DHA yield in cultures using mixed wastewater containing 5% SWW reached 19.08 and 2.66 g/L, respectively, which were 2.29 and 2.66 times higher than those of cultures using control medium. Moreover, a good wastewater treatment performance was achieved as approximately 60% of the COD, TN, and TP were reduced in the cultures using mixed wastewater with a SWW ratio of 5%. The mixed wastewater presented better performance on DHA production than control medium using all tested carbon sources including glucose, fructose, and pure and crude glycerol. The components of control medium can be completely replaced by the mixed wastewater and crude glycerol. It is expected to effectively decrease the medium cost for DHA production and reduce the environmental risk of food processing wastewater.

Quality indicators in lactose hydrolyzed milks and soy beverages from Colombia

Worldwide there is great interest in producing low lactose milk and drinks, such as soy beverages, suitable for consumption by lactose-intolerant people. These products have different carbohydrate compositions, which affect quality indicators derived from Maillard reaction (furosine and 5-hydroxyl-methyl furfural, HMF). In this study, quality parameters have been determined in 11 commercial samples (8 lactose-hydrolyzed milks and 3 soy beverages). Presence of β-galactooligosaccharides in milks (22.2-458.1 mg/100 mL) correlating roughly with the remaining lactose content (1.9-357.7 mg/100 mL). Soy beverages contained α-galactosides in concentrations of 30-75 mg/100 mL. HMF and furosine were detected in all milk samples. In addition, powdered milks subjected to controlled storage (40 °C, a_w 0.44) showed a furosine increase up to 88%. In conclusion, a great composition diversity was observed in the different products, probably favored by the lack of regulation and underline the importance of controlling processing and storage conditions to preserve product quality.

Impact of environmental stresses on the stability of acidic oil-in-water emulsions prepared with tofu whey concentrates

The emulsifying properties of tofu-whey concentrates (TWCs) at pH 3.0, 4.0, and 5.0, and the stability of the resultant oil-in-water emulsions against freeze-thawing (24 h, −20 °C) and controlled or mechanical stress (orbital stirring at 275 rpm, 40 min) were addressed. TWCs were prepared from tofu-whey by heating at 50 °C (8.0 kPa) or 80 °C (24.0 kPa), dialysis (4 °C, 48 h), and freeze-drying, giving the samples TWC50 and TWC80, respectively. The particle size and interfacial properties at the oil/water interface were measured. Emulsions were prepared by mixing the TWC aqueous dispersions (1.0% protein w/w) and refined sunflower oil (25.0% w/w) by high-speed and ultrasound homogenization. The preparation of TWCs at higher temperatures (80 °C) promoted the formation of species of larger particle size, a slight decrease of interfacial activity, and the adsorption of more rigid biopolymer structures associated with an increase of film viscoelasticity in interfacial rheology measurements. The emulsifying properties of both concentrates were enhanced with decreasing pH (5.0–3.0), through a significant decrease of particle size (D_4,3) and flocculation degree (FD), but only those prepared with TWC80 exhibited higher stability to freeze-thawing and mechanical stress at pH 3.0. This could be ascribed to a combination of low initial D_4,3 and FD values, high protein load, and the presence of rigid species that impart high viscoelasticity to the oil/water interface. These results would be of great importance for the utilization of TWCs as food emulsifiers in acidic systems to impart high stability to environmental stresses.

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Tofu whey concentrates (TWCs) were prepared by heating (50 °C, 80 °C) at reduced pressure.

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The emulsifying properties of TWC50 and TWC80 were evaluated at pH 3.0, 4.0 and 5.0.

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The emulsifying properties of TWC50 and TWC80 were enhanced at pH 3.0.

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For TWC80 emulsions, the freeze-thaw stability was enhanced at pH 3.0.

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TWC80 emulsions showed a high stability to mechanical stress at pH 3.0.

Metabolite dynamics and phytochemistry of a soy whey-based beverage bio-transformed by water kefir consortium

Integrated metabolomic and metagenomic techniques were used to study the metabolite dynamics and phytochemistry of a soy whey-based beverage bio-transformed by water kefir consortium. The UPLC- MS/MS and HPLC-ESI-MS metabolite quantification and the OPLS-DA result showed that the kefir consortium induced a significant change in the metabolite composition and altered the phytochemistry of the fermented beverage. Bioactive peptide analogues, flavonoids, and glycerophospholipids including N-acetyl-L-phenylalanine, acetyl-DL-leucine; tephcalostan, wogonin, pelargonin, genistein, daidzein, and glycerophosphoserines (PS), glycerophosphoethanolamines (PE) respectively were synthesized while flavonoid glycosides and soyasaponins were degraded in the novel beverage. Furthermore, the beverage showed high ACE inhibitory and DPPH radical scavenging activity of 92.31% and 87.51% respectively. Lactobacillus, Saccharomyces cerevisiae, and Pichia membranifaciens were the predominant microbial groups in the new beverage as revealed by the metagenomic sequence analysis. The study thus provides discrete data evidence that kefir consortium is a viable starter for transforming soy whey into a bioactive beverage.

The strategies to reduce cost and improve productivity in DHA production by Aurantiochytrium sp.: from biochemical to genetic respects

The marine oleaginous protist Aurantiochytrium sp. (Schizochytrium sp.) is a well-known docosahexaenoic acid (DHA) producer and its different DHA products are the ideal substitute for the traditional fish oil resource. However, the cost of the DHA products derived from Aurantiochytrium sp. (Schizochytrium sp.) is still high, limiting their wide applications. In order to reduce the cost or improve the productivity of DHA from the microbial resource, many researches are focusing on exploring the renewable and low-cost materials as feedbacks, and/or the stimulators for biomass and DHA production. In addition, the genetic engineering is also being used in the Aurantiochytrium sp. (Schizochytrium sp.) system for further improvement. These break the bottleneck of the DHA production by Aurantiochytrium sp. (Schizochytrium sp.) in some degree. In this review, the strategies used currently to reduce cost and improve DHA productivity, mainly from the utilizations of low-cost materials and effective stimulators to the genetic engineering perspectives, are summarized, and the availabilities from the cost perspective are also evaluated. This review provides an overview about the strategies to revolve the production cost and yield of the DHA by Aurantiochytrium sp. (Schizochytrium sp.), a theoretical basis for genetic modification of Aurantiochytrium sp. (Schizochytrium sp.), and a practical basis for the development of DHA industry. KEY POINTS : • Utilizations of various low-cost materials for DHA production • Inducing the growth and DHA biosynthesis by the effective stimulators • Reducing cost and improving DHA productivity by genetic modification • The availability from cost perspective is evaluated.

Nutrient recovery from tofu whey wastewater for the economical production of docosahexaenoic acid by Schizochytrium sp. S31

Docosahexaenoic acid plays a vital role in human health as it is essential for the proper function of the nervous system and for visual functions. To decrease the cost of docosahexaenoic acid production by Schizochytrium, the cost of the medium should be further decreased. In this study, the use of tofu whey wastewater to culture Schizochytrium sp. for docosahexaenoic acid production was tested, with the goal of reducing the medium cost. The results indicated that tofu whey wastewater presented a better culture performance with respect to biomass, lipid, and docosahexaenoic acid production compared with three traditional media. Through simple pH adjustment, the biomass and docosahexaenoic acid productivity reached 1.89 and 0.24 g/L/day, respectively, which were much higher than those obtained using traditional medium. The removal efficiency of chemical oxygen demand, total nitrogen, and total phosphorus reached 64.7, 66.0, and 59.3%, respectively. Due to the rich nutrients in tofu whey wastewater, the use of extra nitrogen source was avoided and the total medium cost for docosahexaenoic acid production in cultures using tofu whey wastewater was <1/3 of that of traditional media. This result indicated that tofu whey wastewater is an effective and economic basal medium for docosahexaenoic acid production by Schizochytrium sp.

Naturally Fermented Acid Slurry of Soy Whey: High-Throughput Sequencing-Based Characterization of Microbial Flora and Mechanism of Tofu Coagulation

Tofu processing generates large quantities of whey as waste water. Although naturally fermented whey serves as a coagulant, the critical constituents remain unknown. High-throughput sequencing identified predominant Lactobacillus in the naturally fermented acid slurry. Lactobacillus casei YQ336 with high coagulating ability and lactic acid production was isolated and its soy protein coagulating mechanism was determined. The acid in YQ336 fermented acid slurry lowered soy milk pH and reduced negatively charged groups of denatured soy protein, leading to coagulation. Acid slurry metal ions also promoted pH decline; moreover, YQ336-produced protease might partially hydrolyse soy protein, further promoting coagulation. Thus, organic acids, metal ions, and enzymes together promote coagulation, with the former acting as the main contributing factor. This study will pave the way for future industrial application of L. casei YQ336 in acid slurry tofu processing and food manufacturing, thereby potentially reducing resource waste and environmental pollution.

Influence of the Maillard Reaction on the Allergenicity of Food Proteins and the Development of Allergic Inflammation

PURPOSE OF REVIEW

The Maillard reaction (MR) is a non-enzymatic reaction between reducing sugars and compounds with free amino groups such as proteins and takes place during thermal processing and storage of foods. This review aims to discuss potential effects of dietary MR products on the pathological mechanisms of allergic diseases.

RECENT FINDINGS

Since the MR leads to modification of proteins with various types of glycation structures, the impact of the MR on the immunogenicity and potential allergenicity of food proteins in many allergenic foods has been assessed. In addition, recent studies have suggested that the MR products, in particular "advanced glycation end products (AGEs)," contained in the diet may be involved in the development of chronic inflammation by acting as inflammatory components and affecting the gut microbiome. This review found that the biological, immunological, and allergic properties of dietary MR products are diverse due to the complexity of the MR.

Evaluation of five commercial non-Saccharomyces yeasts in fermentation of soy (tofu) whey into an alcoholic beverage

Soy (tofu) whey is a nutritious liquid substrate that is often discarded by tofu manufacturers. Recent research has shown that tofu whey can be converted into a soy alcoholic beverage using Saccharomyces yeasts. In this study, five commercially available non-Saccharomyces yeasts (Torulaspora delbrueckii; Lachancea thermotolerans; Metschnikowia pulcherrima; Pichia kluyveri and Williopsis saturnus) were evaluated in tofu whey fermentation and each of the yeasts showed different growth kinetics and fermentation performance. T. delbrueckii and L. thermotolerans consumed the supplemented sucrose and produced 6-7% (v/v) ethanol, while M. pulcherrima, P. kluyveri and W. saturnus only utilized the endogenous fructose and glucose, producing trace levels of ethanol. Besides, different yeasts showed different β-glucosidase activities with 22-97% reduction in isoflavone glucosides; T. delbrueckii, L. thermotolerans and W. saturnus also decreased the level of GABA in tofu whey. Endogenous volatile compounds (mainly short-chain aldehydes) in tofu whey were reduced to trace levels, but different volatile compounds were produced by different yeasts at varying levels that can contribute to the different aroma profiles of the beverages. Therefore, selection of appropriate non-Saccharomyces yeasts can serve as a new strategy to valorize tofu whey and alter the aroma profile of the beverage.

Composition and metabolism of fecal microbiota from normal and overweight children are differentially affected by melibiose, raffinose and raffinose-derived fructans

The aim of the study was to investigate the metabolism of non-digestible oligo- and polysaccharides by fecal microbiota, using isothermal microcalorimetry. The five tested substrates were raffinose, melibiose, a mixture of oligo- and polysaccharides produced from raffinose by levansucrase, levan synthesized from raffinose, and levan from timothy grass. Two inocula were comprised of pooled fecal samples from overweight or normal-weight children, from healthy adult volunteers and a pure culture of Bacteroides thetaiotaomicron as a reference bacterium for colon microbiota. The growth was analyzed based on the heat evolution curves, and the production of organic acids and gases. Taxonomic profiles of the microbiota were assessed by 16S rDNA sequencing. Raffinose and melibiose promoted the growth of bifidobacteria in all fecal pools. Several pool-specific substrate-related responses to raffinose and melibiose were revealed. Lactate-producing bacteria (Streptococcus and Enterococcus) became enriched in the pool of overweight children resulting in lactic acid as the major fermentation product on short saccharides. Acetic and butyric acids were prevalent at fermentation in the normal-weight pool coinciding with the enrichment of Catenibacterium. In the adult pool, the specific promotion of Bacteroides and Lachnospiraceae by levans was disclosed. In the fecal pool of normal-weight children, levans stimulated the growth of Senegalimassilia and Lachnoclostridium and this particular pool also showed the highest maximum heat production rate at levan fermentation. Levans and raffinose-derived oligosaccharides, but not raffinose and melibiose were completely fermented by a pure culture of Bacteroides thetaiotaomicron. The main conclusion from the study is that fecal microbiota of normal and overweight children have different compositions and they respond in specific manners to non-digestible oligo- and polysaccharides: raffinose, melibiose, raffinose-derived oligosaccharides and levans. The potential of the tested saccharides to support a healthy balance of colon microbiota requires further studies.