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Background: Acid and thermal stabilities are important properties for the preparation of acidic protein beverage. It is an important method for enzymatic modification to improve the functional properties of protein. Irpex lacteus protease showed a selective hydrolysis to soy proteins. The purpose of this study was to investigate the mechanism of enzymatic hydrolysis and its effects on acid and thermal stabilities of soy proteins., Results: The I. lacteus protease selectively hydrolyzed the α and α' subunits of the native soybean β-conglycinin (7S globulin) to produce products that presented as the 55 kDa band upon sodium dodecyl sulfate polyacrylamide gel electrophoresis. The amino acid sequences of 55 kDa polypeptides were analyzed in gel multi-enzyme digestion followed by liquid chromatography-mass spectrometry. By matching the multi-enzyme digestion peptides with the published polypeptide chain sequences of the α and α' subunits, it was confirmed that the 55 kDa polypeptides were formed by eliminating amino acid residues on both sides of the N- and C-terminals. From the published protein structure database (https://www.uniprot.org/), it is known that the cleaved peptide bonds were in extension regions. Non-selective enzyme hydrolysis of both β-conglycinin (7S globulin) and glycinin (11S globulin), with corresponding drastic increases in the degree of hydrolysis, was observed when the substrates were preheated to the denaturation degree of 40% and above. However, 55 kDa hydrolyzed products and B polypeptides showed some extent of resistance to the proteolysis by I. lacteus protease even if denaturation degree was 100%. Both selective and non-selective hydrolysis of soy proteins by I. lacteus protease improved the acid and heat stabilities under the same hydrolysis conditions (enzyme/substrate ratio, time, and temperature)., Conclusion: Enzymatic hydrolysis of soybean proteins by the I. lacteus protease can effectively improve the acid and thermal stabilities of proteins. This discovery is significant to avoid aggregation during processing in the beverage industry. In the near future, the protease has potential application value for modification of other proteins. © 2022 Society of Chemical Industry., (© 2022 Society of Chemical Industry.)

Background: Soybean meal (SBM) is the most common protein source used in the poultry and livestock industries. It has high-quality protein, an excellent amino acid (AA) profile, and positive isoflavone properties. However, the antigen proteins in SBM are unsuitable for young animals. The objective of this study was to identify a Bacillus strain that can degrade soybean antigen proteins, and to evaluate the feasibility of its application in SBM fermentation., Results: Bacillus velezensis DP-2 was isolated from Douchi, a fermented Chinese food. It degraded 96.14% and 66.51% of glycinin and β-conglycinin, and increased the trichloroacetic acid-soluble protein (TCAN) content by 5.46 times in the SBM medium. DP-2 could secrete alkaline protease and neutral protease, with productivities of 5.85 and 5.99 U mL -1 . It had broad-spectrum, antibacterial activities against Rhizopus nigricans HR, Fusarium oxysporum ACCC37404, Penicillium digitatum SQ2, Aspergillus flavus C1, Aspergillus niger ACCC30005, Trichoderma viride YZ1, Candida tropicalis CICC1630, and Salmonella sp. ZY. For SBM fermentation, the optimal inoculum rate, temperature, and fermentation time of DP-2 were 2.21 × 10 7 CFU g -1 , 37 °C, and 48 h, respectively. The fermented soybean meal (FSBM) was cream-colored and glutinous. Its crude protein (CP), soluble protein, and TCA-N content were improved by 13.45%, 12.53%, and 6.37 times, respectively. The glycinin and β-conglycinin content were reduced by 78.00% and 43.07%, respectively, compared with raw SBM., Conclusions: Bacillus velezensis DP-2 has potential as a starter culture for SBM fermentation. © 2020 Society of Chemical Industry., (© 2020 Society of Chemical Industry.)

Background: Selenium (Se) is an essential element for humans and animals. Rice is one of the most commonly consumed cereals in the world, so the agronomic biofortification of cereals with Se may be a good strategy to increase the levels of daily intake of Se by the population. This study evaluated the agronomic biofortification of rice genotypes with Se and its effects on grain nutritional quality. Five rates of Se (0, 10, 25, 50, and 100 g ha -1 ) were applied as selenate via the soil to three rice genotypes under field conditions., Results: Selenium concentrations in the leaves and polished grains increased linearly in response to Se application rates. A highly significant correlation was observed between the Se rates and the Se concentration in the leaves and grains, indicating high translocation of Se. The application of Se also increased the concentration of albumin, globulin, prolamin, and glutelin in polished grains., Conclusion: Biofortifying rice genotypes using 25 g Se ha -1 could increase the average daily Se intake from 4.64 to 66 μg day -1 . Considering that the recommended daily intake of Se by adults is 55 μg day -1 , this agronomic strategy could contribute to alleviating widespread Se malnutrition. © 2019 Society of Chemical Industry., (© 2019 Society of Chemical Industry.)

Background: Lupin-based food, due to the high content of functional proteins and phenolic compounds, are widely used in human nutrition. Unfortunately, proteins and phenolic compounds can easily interact with each other which results in formation of complexes that affect properties of both components. Therefore, in this study, composition of the seeds storage proteins isolated from Lupinus albus and L. angustifolius and their interactions with native flavonoids were investigated., Results: Based on the chromatographic separations, six proteins fractions of lupin seeds storage proteins were identified. The results indicate that two dominant fractions, α-conglutin and β-conglutin, constitute up to 80% of all proteins present in the seeds. Three flavonoids interacting with the proteins were identified as apigenin C-glycosides. The lowest flavonoids content was noted in the main storage proteins while in both lupin seeds species over 90% of flavonoids interacted with the proteins present in late-embryogenesis abundant (LEA) protein fraction., Conclusions: Protein-phenolic compound complexes can affect the digestibility of proteins and bioavailability of phenolic compounds, and thus the functional and nutritional properties of products derived from lupin seeds can be changed. Therefore, a better understanding of factors affecting the nutritional value of lupin seeds proteins and flavonoids is necessary to optimize the biological use of this plant for human nutrition. © 2019 Society of Chemical Industry., (© 2019 Society of Chemical Industry.)

Background: Rice structure is important to rice grain and starch breakdown during digestion. The objective of this study was to determine the gastric emptying and rice composition during gastric digestion of cooked brown and white medium-grain (Calrose variety) rice using the growing pig as a model for the adult human., Results: Brown and white rice did not show significantly different gastric emptying rates of dry matter or starch, but brown rice had slower protein emptying (P < 0.05). Moisture content was greater and pH was lower in the distal stomach compared to the proximal stomach (P < 0.0001), and varied with time (P < 0.0001). The mechanism of physical breakdown for brown and white rice varied. Brown rice exhibited an accumulation of bran layer fragments in the distal stomach, quantified by lower starch and higher protein content., Conclusion: The quantity of gastric secretions observed after a brown or white rice meal may be related to the meal buffering capacity, and are accumulated in the distal stomach. The delayed rate of protein emptying in brown rice compared to white rice was most likely due to the accumulation of bran layers in the stomach., (© 2013 Society of Chemical Industry.)

Background: During traditional cocoa processing, the end of fermentation is empirically determined by the workers; consequently, a high variability on the quality of fermented cocoa beans is observed. Some physicochemical properties (such as fermentation index) have been used to measure the degree of fermentation and changes in quality, but only after the fermentation process has concluded, using dried cocoa beans. This would suggest that it is necessary to establish a relationship between the chemical changes inside the cocoa bean and the fermentation conditions during the fermentation in order to standardize the process., Results: Cocoa beans were traditionally fermented inside wooden boxes, sampled every 24 h and analyzed to evaluate fermentation changes in complete bean, cotyledon and dried beans. The value of the fermentation index suggested as the minimal adequate (≥1) was observed at 72 h in all bean parts analyzed. At this time, values of pH, spectral absorption, total protein hydrolysis and vicilin-class globulins of fermented beans suggested that they were well fermented., Conclusion: Since no difference was found between the types of samples, the pH value could be used as a first indicator of the end of the fermentation and confirmed by evaluation of the fermentation index using undried samples, during the process., (© 2013 Society of Chemical Industry.)

Background: Consumers expect organic produce to have higher environmental, health and sensory related qualities than conventional produce. In order to test sensory differences between bio-dynamically, bio-organically and conventionally grown winter wheat (Triticum aestivum L., cv. Runal), we performed double-blinded triangle tests with two panels on dry wholemeal flour from the harvest years 2006, 2007 and 2009 and from two field replicates of the 'DOK' long-term farming system comparison field trial near Basel, Switzerland. Yield and quality parameters were also assessed., Results: Significant farming system effects were found for yield (up to 42% reduction in the organic system), thousand kernel weight, hectolitre weight and crude protein content across the three years. In the triangle tests one out of 12 pair-wise farming system comparisons (PFSCs) on wholemeal flour made from the different wheat samples showed significant sensory differentiation (between bio-dynamically and conventionally grown wheat). When all data from the three harvest years and two panels were aggregated, a statistically significant effect (P = 0.045) of PFSCs on the number of correct answers became evident., Conclusions: Although testing of dry wholemeal flour was very challenging for panellists, we were able to show that sensory differences between farming systems can occur., (Copyright © 2012 Society of Chemical Industry.)

Background: This study evaluated the effects on lamb growth, carcass traits and meat quality of replacing conventional soybean meal in the diet with alternative legume grains., Results: Twenty-eight male lambs of Comisana breed weighing 16.9 ± 2.7 kg at weaning (66 ± 6 days old) were assigned to one of four diets. Until slaughter at 129 ± 6 days of age, each group received ad libitum pelleted alfalfa hay and concentrates differing in the source of protein: chickpea, faba bean, pea or soybean meal. Lambs fed chickpea showed higher dry matter and protein intakes from concentrate than those fed soybean. Lambs' growth, carcass weight and net dressing percentage did not vary by protein source, although chickpea lambs had more perirenal and pelvic fat than those in the soybean group. Diet did not affect chemical composition, colour, thawing and cooking losses, tenderness, and sensory properties of meat. Chickpea increased trans-vaccenic and linoleic acid, and chickpea and faba bean increased the isomers of conjugated linoleic acid., Conclusions: Legume grains can completely replace soybean meal in concentrate, resulting in lamb carcasses and meat of comparable quality. Chickpea leads to an increase in feed intake of lambs and in fat depots in the carcass, and a more beneficial fatty acid profile., (Copyright © 2012 Society of Chemical Industry.)

Background: Many research studies have investigated the impact of agronomical factors on the protein content of pea (Pisum sativum). This study aimed to establish if a correlation exists between protein content and legumin/vicilin (L/V) ratio in pea seeds and to identify agronomical factors that have an impact on this ratio., Results: The L/V ratio was positively correlated with protein content (r = 0.58, P ≤ 0.01), but no linear regression was applicable (adjusted R(2) = 0.31). Both variety and cultivation year had a highly significant effect on the ratio (P < 0.001). The interaction between these two factors was also highly significant (P < 0.001), some varieties being less sensitive to climatic conditions than others. Cultivation location had a highly significant effect (P < 0.01). There was no interaction between variety and location. Seeding density had a highly significant effect on the ratio (P < 0.01), with a saturation effect above 60 seeds m(-2)., Conclusion: Further studies should establish if a linear regression model can be applied to pea varieties independently. Varieties with a stable L/V ratio can prove to be useful in the food industry. Other agronomical factors (soil type and seeding density) should be considered for the production of pea seeds with a specific L/V ratio., (Copyright © 2011 Society of Chemical Industry.)

Background: Baru (Dipteryx alata Vog.) is a fruit distributed throughout the Brazilian savanna and contains a seed with a high protein content, whose properties have been rarely explored. The purpose of this study was to characterize this protein, especially by isolation and quantifying its fractions and measuring some of its molecular properties., Results: Baru seeds contain 244 g kg(-1) protein on a dry weight basis. Solubility profiles showed a preponderance of globulins. This fraction dominated the seed composition, with 61.7 wt% of the total soluble proteins. Albumins and glutelins accounted for 14 and 3.3 wt%, respectively. SDS-PAGE resolution of albumin and globulin showed main bands with molecular weights of 84 kDa and 64, 66 and 73 kDa, respectively. The total protein of the flour and the globulin showed values of in vitro digestibility of 85.59% and 90.54%, relative to casein. Total globulin produced only one chromatographic peak, both on Sepharose CL-6B gel filtration and on DEAE-cellulose ion-exchange columns, eluted at a concentration of 0.12 mol L(-1) NaCl., Conclusion: The baru seed had high protein content with large quantities of storage proteins. The chromatographic and solubility profiles indicate the predominance of a fraction with characteristics of a legumin-type protein., (Copyright © 2011 Society of Chemical Industry.)