Raw Soy Research Articles

Effect of microwave heat processing on nutritional, antioxidant, antinutrient, and sensory indices of soy flour enriched functional noodles

Soybean is considered a plausible carrier of health-promising potential phytonutrients; the soybean also contains higher magnitudes of antinutrients like tannins, phytates, trypsin, protease, and oxalates. Therefore, the present study was carried out to reduce the load of antinutrients using microwave (Mw) heat processing at 0.9 kW for 1.5 min, also assessing its effect on soy flour's nutritional, antioxidant, and value-addition properties. Results for nutritional composition of raw soy flour (RSF), microwave heat processed soy flour (MwSF) and supplemented noodles delineated the presence of higher ash (3%), dietary fibers (6.1%), proteins (42%), Zn (3.5 mg/100g), Ca (238 mg/100g), Mg (208 mg/100g) and K (355 mg/100g) in MwSF then RSF. However, MwSF supplemented noodles prepared at 2-6% supplementation levels (T1-T3) elucidated significant (p<0.05) improvement in ash (0.7-1.1%), fiber (3.7-4.1%), crude protein (10-17%), Zn (3.6-3.8 mg/100g), Ca (39-50 mg/100g), Mg (134-139 mg/100g) and K (440-446 mg/100g). Processing of raw soy flour by microwave heating was observed to reduce tannins, phytates, trypsin, protease, and oxalates by 88, 87, 93, 95, and 90%, respectively. The maximum supplementation of MwSF at 6% in the supplemented noodles significantly (p<0.05) improved the total phenolic contents (TPC), total flavonoid contents (TFC), ferric reducing antioxidant power (FRAP), and 2,2-Diphenyl-1-picrylhydrazyl (DPPH) from 131-142 mg GAE/100g, 52-57 mg GAE/100g, 217-233 μmol/100g and 37-40%, respectively. Organoleptic evaluation of MwSF-supplemented noodles suggested the highest sensory acceptability at ≤4% supplementation level (T2). The study also suggests microwave heating as a viable approach to improve value-added goods' nutritional and antioxidant potential with the least safety concerns.

Enhanced creaminess of plant-based milk via enrichment of papain hydrolyzed oleosomes

There is an increased consumer demand for plant-based milk in substituting dairy milk due to the ethical, health concerns and environmentally-friendly choice. However, perceived creaminess as dominant attributes present a big challenge in consumer acceptance for those milk alternatives. In this study, we developed a novel and easily scalable strategy to enhance the creaminess of soy milk via enrichment of oleosomes. The soybean oleosome creams were extracted and hydrolyzed with papain, resulting in formation of oil droplets with more phospholipid and less protein at the surface, which significantly reduce friction coefficient in the presence of saliva (from 0.15 to 0.03 at a speed around 50 mm/s). Moreover, blending papain-hydrolyzed oleosome creams with raw soy milk enables the creation of a plant-based milk that matches the nutritional profile, lubrication properties, and creaminess of full-fat dairy milk. QCM-D and passive microrheology were employed to characterize hydration of oleosomes into the mucin layer and relevant viscosity change, suggesting that papain hydrolyzed oleosome might decrease friction coefficient via hydration lubrication mechanism. This approach could be applied to enhance the creaminess mouthfeel and nutritional profile of plant-based milk.

Pyrolysis of plasticized films based on soy protein, denatured by different substances

Polymer films based on soy protein isolate (SPI) were obtained using the thermo-pressing method. Plasticizers and denaturing agents were added to ensure better the film-forming properties and reduce the fragility of the resulting materials. Glycerol, sorbitol and their mixture were used for plasticization, while solutions of alkali (potassium hydroxide), surfactants of natural origin (sodium coco sulfate) and reducing agent (sodium sulfite) were used for denaturation. By combining different types of plasticization and denaturation, a series of samples were obtained and compared with a sample based on raw soy protein. In addition to the obvious differences in the appearance of the films, the processes of their thermal degradation, studied by pyrolysis mass spectrometry, also differed significantly. In fact, unprocessed soy protein has the highest thermal stability with the temperature of the most intensive decomposition equal to 270 °С, which can decrease to 200 °С under the conditions of denaturation and plasticization. Despite the increase in the number of film components, the amount of volatile decomposition products decreases (from 86 to 32), as well as the molecular weight of the heaviest of them (from 169 to 74). This is a sign of a change in the mechanism of soy protein degradation due to denaturation and plasticization caused by transformations in its supramolecular structure, such as unfolding and extension of macrochains with increased availability of functional groups. The pyrolytic behavior of some protein samples plasticized with sorbitol is closest to that of untreated soy protein, which may indicate a lower plasticizing efficiency of sorbitol with longer molecules than glycerol. The interpretation of the recorded mass spectra of the volatile pyrolysis products showed that the thermal degradation of protein materials is dominated by processes such as decarboxylation, dehydration, deamination and decarbonylation, while in the presence of plasticizers the splitting of their own molecules also becomes dominant. The characteristic mass spectra of protein films denatured by surfactants also contain ionic fragments of relatively high molecular weight, probably derived from sodium coco sulfate molecules.

Uncovering differences in the composition and function of phage communities and phage-bacterium interactions in raw soy sauce.

Although the composition and succession of microbial communities in soy sauce fermentation have been well-characterized, the understanding of phage communities in soy sauce remains limited. This study determined the diversity, taxonomic composition, and predicted function of phage communities and the phage-host interactions in two types of raw soy sauce (Cantonese-type fermentation, NJ; Japanese-type fermentation, PJ) using shotgun metagenomics. These two raw soy sauces showed differences in phage composition (121 viral operational taxonomic units (vOTUs) in NJ and 387 vOTUs in PJ), with a higher abundance of the family Siphoviridae (58.50%) in the NJ phage community and a higher abundance of Myoviridae (33.01%) in PJ. Auxiliary metabolic functional annotation analyses showed that phages in the raw soy sauces mostly encoded genes with unknown functions (accounting for 66.33% of COG profiles), but the NJ sample contained genes mostly annotated to conventional functions related to carbohydrate metabolism (0.74%) and lipid metabolism (0.84%), while the PJ sample presented a higher level of amino acid metabolism functions (0.12%). Thirty auxiliary metabolism genes (AMGs) were identified in phage genomes, which were associated with carbohydrate utilization, cysteine and methionine metabolism, and aspartic acid biosynthesis for the host. To identify phage-host interactions, 30 host genomes (affiliated with 22 genera) were also recruited from the metagenomic dataset. The phage-host interaction analysis revealed a wide range of phage hosts, for which a total of 57 phage contigs were associated with 17 host genomes, with Shewanella fodinae and Weissella cibaria infected by the most phages. This study provides a comprehensive understanding of the phage community composition, auxiliary metabolic functions, and interactions with hosts in two different types of raw soy sauce.

Co‐culture relationship between Zygosaccharomyces rouxii and Candida versatilis and its effect on the flavour of soy sauce

SummaryZygosaccharomyces rouxii and Candida versatilis are important flavour‐producing yeasts in soy sauce fermentation. In the present study, the interaction between Z. rouxii and C. versatilis co‐cultures in YPD and raw soy sauce medium was investigated and applied to soy sauce fermentation. The concentration of Z. rouxii in the co‐culture was 0.47 times that in the mono‐culture. This observation suggested that C. versatilis inhibited the growth of Z. rouxii, likely attributed to various factors, including the production of acids and heat‐ and protease‐sensitive substances by C. versatilis. Furthermore, we examined the physicochemical properties and characteristic volatile flavour components of soy sauce by adding varying ratios of Z. rouxii and C. versatilis at different stages of fermentation. The results showed that mixed fermentation of Z. rouxii and C. versatilis enhanced the total nitrogen, amino acid nitrogen, 4‐hydroxy‐2(5)‐ethyl‐5(2)‐methyl‐3(2H)‐furanone, and volatile compounds in soy sauce compared to single‐strain fermentation. Additionally, optimal soy sauce results were obtained when yeasts were added on day 45, with an inoculation ratio of 1:1. In conclusion, during the moromi fermentation stage, the appropriate selection of the inoculation ratio and time for Z. rouxii and C. versatilis addition can effectively enhance the physicochemical properties and flavour attributes of soy sauce.

Comparison of high-hydrostatic pressure and frozen treatments on raw freshwater clam marinated in soy sauce: Impact on microbiological and organoleptic qualities

The purpose of this study was to compare how the two different methods of food processing, high pressure processing (HPP) under 300–500 MPa for 3 min and freezing, affect the microbiological, chemical, and organoleptic qualities of soy sauce-marinated freshwater clams (Corbicula fluminea) during refrigeration. The aerobic plate count (APC), psychotropic bacteria count (PBC), Salmonella spp., and coliform of high pressure processed soy sauce-marinated clams (HPP marinated-clams) were obviously lower than conventionally frozen soy sauce-marinated clams (frozen marinated-clams), or were not detected. In addition, after all samples’ 15-day refrigeration period, HPP was found to significantly inhibit the growth of APC, PBC, Salmonella spp., and coliform, while the microbial counts of frozen marinated-clams increased gradually with time. However, the surface areas, moisture contents, and salt contents of all samples of both HPP marinated-clams and frozen marinated-clams slightly increased during refrigeration. Furthermore, the results of organoleptic analyses exhibited that the storage life of marinated clams can be increased from 9 days under freezing treatment to 15 days under HPP (300 MPa and 500 MPa). Using high-throughput sequencing, HPP treatment significantly changed the microbiota of marinated clam and delayed the spoilage process. Therefore, the study suggests using HPP at least 300 MPa for 3 min to effectively inhibit the microbial growth and significantly extend the storage life of the samples during the refrigeration period. This is a first study to use HPP technology to replace the traditional freezing technology in the application of raw soy sauce-marinated freshwater clam products, and at the same time, HTS was used to evaluate the changes of microbiota during refrigeration.

Evaluation of Nutrient Compositions and Heat Processing Factors of Raw Soy and Full-Fat Soybean Using Chemical and Spectrophotometric Methods

Bu çalışmada çiğ soya ve tam yağlı soyanın (TYS) besin madde içeriklerinin kimyasal ve spektrofotometrik analizlerle belirlenmesinin yanı sıra soya ve TYS örneklerinde ısıl işlem parametrelerinin spektrofotometrik metotla saptanması amaçlanmıştır. Dört farklı işletmeden alınan çiğ soya ve TYS yemlerinin her birinden 25 adet olmak üzere toplam 75 örnek üzerinde çalışılmıştır. Çiğ soya, normal (119-134°C) ve yüksek sıcaklıkla (135-141°C) işlenmiş tam yağlı soya grupları (TYS-NS ve TYS-YS) kendi aralarında değerlendirilmiştir. Örneklerin besin madde içeriği kimyasal metotlarla ve Yakın Kızılötesi Yansıma Spektrofotometre (NIRS) cihazı kullanılarak saptanmıştır. Ayrıca, spektrofotometrik olarak lizin ve metiyonin amino asit değerleri de ölçülmüştür. Bunların yanısıra, NIRS cihazıyla ısıl işlem parametrelerinden protein dağılım indeksi (PDİ), Potasyum hidroksit’de protein çözünürlüğü (KOH-PÇ), tripsin inhibitör aktivitesi (TİA), reaktif lizin (R-lizin) değerleri belirlenmiştir. Çiğ soyaya göre farklı ısıl işlem uygulanan TYS gruplarında PDİ, KOH-PÇ ve TİA değerleri düşerken (P

Structural and functional relationships of plant allergenic proteins: gastrointestinal metabolism and structural heterogeneity

The prevalence of food allergies has increased in recent decades and affects up to 5% of the population, frequently resulting in severe symptoms. Specific structures of the corresponding proteins, the epitopes, are recognized by T‐cell receptors or IgE antibodies, resulting in an immune response. Many food allergens and immunogenic proteins for various plant‐based foods have been investigated thoroughly on different levels. However, research into the gastrointestinal metabolism of plant‐based food allergens on the molecular level is scarce, so far. The aim of this thesis was to characterize the gastrointestinal metabolism of food allergens and proteins involved in celiac disease, and to derive global properties that account for the immunogenic and allergenic potential of these proteins. Raw walnut, raw and cooked soybeans, and wheat‐based bread have been chosen as representatives for tree nuts, legumes and cereals, in order to adress the given research question. The project is divided into three sub‐steps, which are as follows: Adaption of the in vitro digestion model to different matrices and comprehensive analysis of proteins and peptides Development of a data‐processing strategy to enable visualisation of the resulting data Interpretation of the data regarding the gastrointestinal metabolism of relevant proteins in different matrices The in vitro digestion model by Minekus et al. was successfully adapted to simulate gastrointestinal digestion of a variety of food matrices. The analytical approach at protein level by SDS‐PAGE analysis and in‐gel digestion, combined with mass spectrometry at peptide level, enabled comprehensive identification of degradation products. As an example, up to 7279 peptides were assigned to soy proteins over the course of gastral digestion of raw soy, and a further 1027 peptides for samples of simulated intestinal digestion. In order to deal with these huge amounts of data, various data processing steps have been designed. Peptide identification by PEAKS® was extended using scripts in Python, to perform label‐free quantification of mass spectrometry data and to compare the identified degradation products with known epitopes. The multistage preprocessing approach developed in Python provided the basis for a set of data visualisations to further interpret the behaviour of proteins during gastrointestinal digestion. Analysis at protein and peptide levels revealed that quantities of most of the analysed proteins for all matrices exhibited stability against gastrointestinal digestion. Analysis of the resulting sequence coverage over the course of gastrointestinal digestion, combined with label‐free quantification in 3D surface plots, allowed conclusions on the behaviour of distinct protein regions over time. This approach provided detailed insights into the multistage formation and degradation mechanisms of differently sized peptides. ‐gliadin‐assigned peptides covering epitopes related to food allergy, as well as eight peptides covering celiac disease related epitopes, was characterized by label‐free quantification, outlining enhanced resistance against gastrointestinal digestion. Bioinformatic tools were applied to provide further characteristics of all proteins of interest related to the amino acid sequence. Sequence alignment with secondary structure features. The given results of this thesis provide insight into the stability of the proteins involved in adverse reactions to food, such as allergy or celiac disease, throughout the process of gastrointestinal digestion.

Application of electronic tongue in umami detection and soy sauce refining process.

The article systematically investigated the response behaviors of lipid-film equipped umami taste sensor to various umami compounds, including typical umami substances (umami amino acids, GMP, IMP, disodium succinate) and novel umami chemicals (umami peptide and Amadori rearrangement product of umami amino acid). The umami taste sensor has great specificity to all umami substances. Relationships between output values and concentrations of umami substances in certain ranges were consistent with Weber-Fechner law. The umami synergistic effect detected by the sensor was in great agreement with human sensory results as well, fitting logarithm model. Moreover, the taste profile mixing model of raw soy sauce was established using five different taste sensors and principal component analysis, realizing the simplification of soy sauce blending and acceleration of the soy sauce refining process. Thus, flexible design of the experimental procedure and multi-analysis of the sensor data is essential.

Effect of Various Seasonings on Protease Activity in Raw Soy Sauce

Raw soy sauce, which is not sterilized, has a bright color and mild aroma, and possesses residual enzymatic activity to break down proteins and starch. Raw soy sauce is often used in combination with other seasonings. The enzymatic activity in raw soy sauce may be affected by the type of seasonings used in combination. In the present study, we examined the effect of cooking with other seasonings on the enzyme activity in raw soy sauce in a model experiment simulating actual cooking. In addition to raw soy sauce, we used white sugar, mirin (hon mirin, mirin-style seasoning, and boiled-down hon mirin), cooking sake, and grain vinegar as seasonings. Protease activity was measured under several heating conditions. When heated at 60&amp;deg;C, the degree of enzyme inactivation decreased as the ratio of the combination of white sugar, mirin-style seasoning, and boiled-down hon mirin increased. The results of the present study suggest that carbohydrate compounds commonly contained in each seasoning have a protective effect on the enzymes in raw soy sauce.

The effect of soy processing on its allergenicity: Discrepancy between IgE binding and basophil stimulation tests

Presently, many studies assess allergenicity via IgE immunoblotting and IgE binding tests; however, IgE detection does not always signal the manifestation of a clinical allergy. However, the capacity of food allergens to trigger basophils makes it possible to use the in vitro functional basophil activation test (BAT) to assess allergenicity. The effect of the Maillard reaction (MR) on the allergenic potential of processed soy proteins was evaluated by two IgE binding tests (Competitive ELISA and Inhibition ImmunoCAP), a Western Blot and a functional BAT; with the aim to analyze whether the sIgE binding results correspond to the functional assay results. The results between the IgE binding tests and the functional assay were in-line for 2 of the 6 studied patients. For one patient there was no correlation between any of the results. For the raw soy protein extract heated with glucose for 10 and 30 min (SH SPE + Glu and LH SPE + Glu, respectively), the results were in-line for only 3 out of the 6 patients. Thus, the present study shows a discrepancy between IgE binding tests and basophil stimulation when assessing the effect of soy processing on its allergenicity. Since IgE-binding capacity does not always correlate to IgE cross-linking capacity, the conclusions of the allergenic potential based on the IgE binding tests alone should be drawn with care and further studies on this matter would benefit from the inclusion of a functional assay such as the BAT.

Nutritional, Phytochemical, and In Vitro Antioxidant Activity Analysis of Different States of Soy Products.

Consumer demand for food nutritional content and quality is driving the design of plant-based foods that are enhanced with proteins. In this study, we aimed to reveal the nutrient compositional differences of various states of soy flours. We compared soy protein concentrate (SPC) with full fat (FF), raw soy flour (RSF), and defatted (DF) soy flour for investigating nutritional content, phytochemicals, and in vitro antioxidant activity. The results showed that the SPC contained significantly (p < 0.001) higher protein content (65.14%) and low-fat content (0.54%) than RSF, FF, and DF. Furthermore, the findings revealed that all products contain a significant (ANOVA, p < 0.001) amount of essential minerals. The RSF contains significantly higher (p < 0.001) potassium (1178.6 mg), calcium (216.77 mg), and magnesium (247 mg) per 100 g than FF, DF, and SPC. SPC contains essential amino acids, but we were unable to detect phenylalanine and tryptophan due to a limitation in the method. Furthermore, using methanolic and aqueous extracts of RSF, FF, DF, and SPC, the flavonoid, phenolics, and antioxidant capacity were also evaluated. According to the findings, soy products in methanolic extract had higher phenolic (about 12-34 mg/g) and flavonoid (about 63-150 mg/g) levels than aqueous extract. Results also demonstrated that FF had higher phenolic content, and SPC had higher flavonoid content than the other products. In vitro models such as phosphomolybdenum blue, FRAP, DPPH, and ABTS assays were used to study the total antioxidant and free radical scavenging potential of soy products, and results found that soy products contained a significant (p < 0.001) amount of antioxidant equivalent to gallic acid and vitamin C standard. In the DPPH and ABTS assays, the results also showed that soy products can reduce free radicals in different in vitro models. Altogether, these findings suggest that soy flours, particularly DF and SPC, could be a beneficial food ingredient in the formulation of functional foods.

Improving Soy Sauce Aroma Using High Hydrostatic Pressure and the Preliminary Mechanism.

Using high hydrostatic pressure (HHP) to treat liquid foods can improve their aroma; however, no information about the effects of HHP on soy sauce aroma has yet been reported. The effects of HHP on the aroma of soy sauce fermented for 30 d were investigated using quantitative descriptive analysis (QDA), SPME–GC–olfactometry/MS, hierarchical cluster analysis (HCA) and principal component analysis (PCA). Results showed that the pressure used during HHP treatment had a greater influence on soy sauce aroma than the duration of HHP. Compared to the control, soy sauce that was treated with HHP at 400 MPa for 30 min (HHP400–30) obtained the highest sensory score (33% higher) by increasing its sour (7%), malty (9%), floral (27%) and caramel-like (47%) aromas, while decreasing its alcoholic (6%), fruity (6%) and smoky (12%) aromas; moreover, the aroma of HHP400–30 soy sauce was comparable with that of soy sauce fermented for 180 d. Further investigation demonstrated that HHP (400 MPa/30 min) enhanced the OAVs of compounds with sour (19%), malty (37%), floral (37%), caramel-like (49%) and other aromas (118%), and lowered the OAVs of compounds with alcoholic (5%), fruity (12%) and smoky (17%) aromas. These results were consistent with the results of the QDA. HHP treatment positively regulated the Maillard, oxidation and hydrolysis reactions in raw soy sauce, which resulted in the improvement and accelerated formation of raw soy sauce aroma. HHP was capable of simultaneously improving raw soy sauce aroma while accelerating its aroma formation, and this could treatment become a new alternative process involved in the production of high-quality soy sauce.

Microbiota and Mycobiota of Soy Sauce-Supplied Lactic Acid Bacteria Treated with High Pressure

Background: Ethyl carbamate (EC), a byproduct that naturally forms in fermented foods, can cause tumors and cell death and is classified as a probable human carcinogen (Group 2A). EC is naturally formed through the alcoholysis reaction between ethanol and carbamyl compounds. The major precursors and dominantly emerging stages of EC differ with disparate food types, including soy sauce. This work aimed to clarify the formation of EC and its influence factors throughout the soy sauce production process with or without high-pressure process (HPP) treatment. Methods: Tetragenococcus halophilus, Pediococcus acidilactici, Zygosaccharomyces rouxii, and Candida versatilis were added to soy sauce. The levels of citrulline and EC were measured, and a 16S and ITS assay investigated the microbiota. Results: L-citrulline production was found in each group after fermentation for one month. In addition, L-citrulline levels were generated the most in group D (500 MPa treated raw soy sauce with 12% saltwater and mixed fermentation bacteria, including T. halophilus,P. acidilactici,Z. rouxii, and C. versatilis) and group E (soy sauce fermentation with 12% saltwater without HPP treatment) compared to group F (soy sauce fermentation with 18% saltwater without HPP treatment). Conclusions: These results indicated that salt concentration and mixed fermentation bacteria (T. halophilus,P. acidilactici,Z. rouxii,C. versatilis) might not be major factors for L-citrulline production.

Physicochemical and nutritional assessment of soy milk and soymilk products and comparative evaluation of their effects on blood gluco-lipid profile

This research work presents the physicochemical and nutritional evaluation of soymilk and soymilk based products like tofu and its by-product okhara and soy yoghurt and a comparative study of their effect on blood gluco-lipid profile in both animal models and Type 2 diabetic patient volunteers. Their nutritional effect were also assessed amongst children and young mothers. All products have significant protein, fat, carbohydrate and crude fiber content. Total polyphenolic content of soymilk was determined to be 2.26±1.02 mg GAE/g; the phytate content in raw soy milk ranged between 0.1-0.3%; trypsin inhibitory activity of soybean was found to be 46.52±0.98. Results have shown the significant nutritional potentials of soymilk and soymilk based products. The average baseline BMI of 16.5 and 19.1 for child and young mothers participants were improved to 18.1 and 19.8 after intake of soy milk and soymilk based products. Okhara significantly (p<0.001) reduced the escalated blood gluco-lipid parameters, followed by soymilk, soy yoghurt and tofu as evident both in animal and human studies. Thus soy milk and soy milk based products not only improve the nutritional status but also an effective nutraceutical adjunct therapy against hyperglycaemia.

Breeding of ‘DND358’: A new soybean cultivar for processing soy protein isolate with a hypocholesterolemic effect similar to that of fenofibrate

• ‘DND358’ is ideal raw soy material for producing hypocholesterolemic SPI powder. • Modify protein subunit compositions is useful strategy for hypocholesterolemic soy breeding. • DND358-SPI: a superior diet-therapy soy beverage to achieve cholesterol homeostasis. • Enrich α′ subunit of 7S can be strategized in hypocholesterolemic soybean breeding. Soy proteins have hypocholesterolemic effects (HCE). Here, we developed a soybean cultivar ‘DND358’, which is superior for processing hypocholesterolemic soy protein isolate beverage powder (DND358-SPI). ‘DND358’ carries four recessive null alleles for the α subunit of 7S globulin and the G1, G2, and G4 subunits of 11S globulin (tetra null), was selected from a population derived from a three-way cross. The tetra null mutation resulted in a compensatory increase in the α′ subunit level and arginine content. The oral administration (300 mg/kg/day) of DND358-SPI processed from ‘DND358’ significantly decreased the fatty liver symptoms and hepatic lipid accumulation; reduced the hepatic total cholesterol (TC), triacylglycerol (TG) levels and atherogenic index (AI) value, in rats fed a high-cholesterol diet. Conversely, DND358-SPI administration markedly elevated high-density lipoprotein cholesterol levels, to values significantly higher to those fed on fenofibrate (FF, 30 mg/kg/day), a hypocholesterolemic drug. The HCE of DND358-SPI were similar to that of FF.

Uticaj trajanja toplotne obrade i vrste bioloških koagulanta na mikrobiološka svojstva nigerijskog mekog sira od soje

The study examines the microbiological properties of cheese from soy milk as influenced by heat treatment durations and biological coagulant types. The soy milk was pasteurized at 65°C and subjected to further heat treatment for 15, 20, and 25 minutes with the addition of coagulants (lime juice, tamarind pulp and moringa seed paste) to respective samples and allowed to cool for 30 minutes before pressing out the whey. The initial properties of raw soy milk were determined to serve as control and the nine produced soy cheese samples were determined using a 3x3 factorial treatment design. The microbiological properties of the cheese were determined using standard methods. Results obtained were analyzed statistically to determine the influence of heat treatment duration and coagulant sample. The microbial analysis revealed that there was Coliform in soy cheese samples which were all less than 1.0 x 102 cfu/g except in F15, F20, and E25 which had 4.2 × 102 , 4.3 × 102 , and 2.1 × 102 cfu/g which are within the permissible limit of consumption. There were no Coliform bacteria in all samples except E15, F20, and F25 which had 1.6x103 , 1.4 x103 , and 4.0 x102 cfu/g, respectively which are also within the permissible limit of consumption. There was no yeast and mould growth on all the samples except E25 which is &lt;1.0x102 cfu/g. This study is initiated to determine the effect of heat treatment and local coagulants on the microbial properties of Nigerian soft soy cheese. Hence, investigating the hygienic quality and safety of consuming the food product.

Culinary Properties of Raw Versus Conventional Soy Sauce during Tuna Preparation

Soy sauce is a traditional Japanese seasoning made from fermented soybeans. As global demand grows, identifying novel soy sauce applications and benefits must become a priority. While conventional soy sauce undergoes heat-sterilization, filter-sterilization produces a lighter-colored (raw) soy sauce with preserved mold enzyme activities. As the impact of raw soy sauce during food (especially seafood) preparation remains unstudied, the present study compared the differential impact of raw and conventional soy sauce on tuna culinary properties. First, soy sauce color and protease activity were assessed. Next, tuna was marinated in soy sauce and non-alcoholic mirin for 0, 10, 35, or 60 min. Finally, marinated tuna properties (mass, salt content, surface salt penetration, color, rupture load, surface wetness, and protein content) were objectively assessed, and subjective sensory evaluation (appearance, aroma, wetness, softness, saltiness, umami, and overall taste) was performed by a blinded panel. Findings confirmed the lighter color of and the preservation of protease activity in raw soy sauce. Raw soy sauce significantly enhanced surface tenderization, salt penetration, and wetness, while both soy sauces increased surface firmness via salt-induced dehydration. Respondents significantly preferred the appearance and saltiness level of raw soy sauce-marinated tuna, and the umami and overall taste of tuna marinated in raw soy sauce for 60 min. The findings of this study, to our knowledge, demonstrate for the first time the potential culinary superiority of raw soy sauce in certain applications, and support future research to further define such applications.

A new sight on soy isoflavones during the whole soy sauce fermentation process by UPLC-MS/MS

Soy sauce fermentation process includes koji-making and moromi fermentation stages, with the moromi stage consisting of solid (okara) and liquid (raw soy sauce) phases. Evolution of soy isoflavones in koji, okara and raw soy sauce samples was analyzed systematically, and the rule regarding the formation of soy isoflavones during the whole fermentation process was firstly figured out. Fifteen kinds of soy isoflavones were detected by UPLC-MS/MS. Following the fermentation process, the soy isoflavones profiles changed dramatically in the initial moromi stage (1 d-15 d). The concentrations of glucosides, malonylglucosides and acetylglucosides decreased and disappeared around at okara-30 d, while the concentrations of aglycones and hydroxyl aglycones increased and attained the peak at 90 d of the moromi stage. Additionally, antioxidant capacities of samples were positively correlated with the concentrations of aglycones and hydroxyl aglycones. Interestingly, in each sample, the antioxidant contribution value of hydroxydaidzein was around 100–500 times higher than that of daidzein, which demonstrated that aglycones, especially hydroxyl aglycones, were the key isoflavones contributed to the antioxidant properties of soy sauce.

Production and Physicochemical Properties of Cake with Different Ratios of Soy Lecithin

This research was geared towards producing and evaluating the physicochemical properties of cake with different ratios of soy lecithin. Soy lecithin was produced by the degumming of raw soy oil by adding 2% water content to the oil and heating to 70oC. Soy oil yield was 31% while lecithin yield was 2.18%. The soy lecithin produced had a yellow-brownish colour. Mixture design was used for the experiment. The soy lecithin was used to replace 50% and 100% egg content in two different cake samples while a third sample had no lecithin. The first sample was made up of 250g wheat flour, 100g Margarine, 65g sugar, 5g baking powder, 2 eggs, 1.25g soy lecithin and 2g salt (MEL2), the second sample was made up of 250g wheat flour, 80g Margarine, 65g sugar, 5g baking powder, 2.5g soy lecithin and 2g salt (MEL3) while the third sample was made up of 250g wheat flour, 100g Margarine, 65g sugar, 5g baking powder, 4 eggs and 2g salt (MEL1). The margarine content of sample MEL3 was reduced by 20%. The physical properties of the cake samples were examined and sample MEL2 gave a better physical appeal than the other samples after baking. The specific volume of sample MEL2 (4.21cm3) was higher than those of samples MEL1 and MEL3. The proximate composition of the samples showed that the moisture content ranged from 32.9 – 34.1%, protein content 5.89 – 6.14%, ash content 1.61 – 1.64%, fat content 14.5 – 15.3% and carbohydrate 43.09 – 44.85%. Sensory evaluation was carried out on the samples to determine the most acceptable and analysis of variance was used to check for significant difference. Sample MEL2 was preferred in taste, colour, texture, flavour and general acceptability and was significantly different from samples MEL1 and MEL3 in general acceptability. It was observed that egg and some fat content in cakes could be replaced with soy lecithin. This study forms a basis for new product development for the pastry food industry.