Soybean germination limits the role of cell wall integrity in controlling protein physicochemical changes during cooking and improves protein digestibility

Effects of germination on the digestibility of instant soybean powders based on an in vitro digestion model of the aged static gastrointestinal tract

Germination and heat processing can improve the digestibility of soybean protein, so for the elderly and people with gastrointestinal dysfunction, instant soybean powder is an ideal source for protein intake. In this study, the changes in protein and anti-nutritional factors in the instant germinating soybean powders were investigated systematically, and the aged gastrointestinal digestion model analyzed the digestive characteristics of instant germinating soybean powders. The results showed that during processing, particle size, disulfide bond, and β-sheets decreased, free sulfhydryl and α-helix increased. The change resulted in the decrease of proteolysis degree and particle size of gastrointestinal digestive products, and the increase of surface hydrophobic index. At the same time, anti-nutritional factors decreased by about 30 % to 60 %. The above reasons are combined with the protein digestibility of S72 5.88 % higher than Y0. This study proved that instant soybean powder is more conducive to the digestion and absorption of the elderly.

Enhancing the Nutritional Composition and Phenolic Compound Content of Sprouted Chickpeas Using Sucrose and Chitosan as Elicitors

The use of elicitors during germination is a strategy to enhance the nutritional quality and biofunctional properties of various legumes, such as chickpeas, which are important sources of proteins and bioactive compounds. The objective of this study was to evaluate the effect of the use of chitosan (CH) and sucrose (SU) during sprouting on protein content, in vitro protein digestibility (IVPD), total phenolic content (TPC), and antioxidant activity (AOX). For this purpose, soaking time, elicitor concentration (CH or SU), and sprouting time were optimized to obtain maximum values for the response variables. The results showed that the optimal conditions for achieving increases in nutritional and biofunctional properties were 1 h of soaking, 0.35% w/v, and 5 days of sprouting for CH, and 2.55 h of soaking, 1% w/v, and 5 days of sprouting for SU. Under these conditions, protein content increased by 7-12%, IVPD by 78-86%, TPC by 379-327%, and AOX by 115% for CH and SU, respectively. Additionally, morphological changes were observed in the cellular structure of chickpea cotyledons, but no changes were detected in the crystalline structure of starch. These results contribute to the understanding of the effect of CH and SU in modifying the nutritional and biofunctional properties of chickpeas.

Germination affects structural and techno-functional properties of proteins from quinoa seeds with increased realease of antioxidant peptides by gastrointestinal digestion

This study investigated the impact of germination on quinoa protein (QP) composition, techno-functional properties, and the release of antioxidant peptides during gastrointestinal digestion. Germinated QP (GQP) at 36 and 48 h showed significant degradation of storage proteins. GQP12 and GQP24 exhibited increased surface hydrophobicity but decreased solubility, foaming, and emulsifying properties, while that of GQP60 and GQP72 were improved. Both QP and GQP demonstrated good digestibility, with over 90 % of their gastrointestinal digests smaller than 1 kDa. Gastrointestinal digests of GQP12 (QPGI12) exhibited excellent antioxidant activity, attributed to higher hydrophobic amino acid content of GQP12 and peptides of QPGI12 digests. Eight antioxidant peptides with strong binding affinity to Keap1 were identified, with peptides FGDL, FGGL, and FDGL interacting through hydrogen bonding and hydrophobic interactions. Findings gained in this study indicated that germination might serve as an efficient strategy for improving techno-functionality and bioactivity of QP for antioxidant peptides production.

Impact of bio-processing treatments on the nutritional and anti-diabetic enzyme inhibitory properties of black wheat, barnyard millet, and black soybean

Objective

The present study assessed the impact of different bio-processing treatments on the in vitro protein digestibility (IVPD) and inhibitory properties against α-amylase and α-glucosidase of whole grains viz. black wheat (BW), barnyard millet (BM), and black soybean (BS) using at initial optimized conditions including soaking and germination.

Method

Nutritional analysis of grains was done using standard AOAC methods and in vitro models were used for assessing the anti-diabetic properties.

Results

Nutritional analysis of the grains revealed significant differences in various parameters. BS having higher levels of moisture, ash, crude protein, crude fat, and physiological energy value compared to BM and BW. Optimization of soaking (0-24 h) and germination (0-72 h) times showed significant improvements in in-vitro protein digestibility (IVPD), trypsin inhibitory activity (TIU/mg), and glycemic index (GI) across all samples. Considering the management of hyperglycemia, BW and BM do not require any prior processing to be utilized for the development of food products. However, for BS, soaking followed by germination for 48 h proved to be an effective processing, that resulted in an IVPD of 68.706% and a GI of 51.03, with a TIU/mg of 23.166. Soaking reduced α-amylase and α-glucosidase inhibition, while germination increased inhibitory activity significantly (p < 0.05).

Conclusion

These findings highlighted the potential benefits of incorporating BW, BM, and BS into the diet for enhanced nutrient intake and better management of hyperglycemia considering the GI and inhibitory activity of α-amylase, α-glucosidase, and trypsin enzymes.

A comparative study on the protein digestion of four different soy beverages: effects of the composition, microstructure, and protein digestibility evaluation method

The increased consumption of soy-based products leads to the incentive for more sustainable soybean processing and more accurate nutritional evaluation. The protein structures and aggregation states of different components vary with different soy products, but their relationship with digestibility is unclear. In order to study the digestion of soy protein in complex food matrices, four soy-based beverages were carefully prepared, including whole component soy beverage (WS), soy beverage with insoluble soybean residue removed (DO-WS), soy beverage with lipids removed (DL-WS), and soy protein isolate beverage (HSPI). During digestion, the microstructure revealed that particles of all soy beverages were reduced and more evenly distributed, but striated fibres (in WS and DL-WS) still remained after digestion. Tricine-SDS-PAGE profiles showed that after in vitro gastrointestinal digestion of the four beverages, almost all the bands corresponding to the complete proteins from soy disappeared, leaving fewer visible bands with a low MW - below 12 kDa. In vitro protein digestibility analyzed by TCA precipitation (strategy B), which ranged from 64.24% to 68.70%, was more accurate, with peptides of MW <1 kDa accounting for over 84% for all the four digested fractions. Moreover, the highest values of in vitro DIAAS (96/80) and digestible protein (29.40/24.41 g per 100 g of soybeans) were achieved by WS. Characterization of the insoluble digesta further elucidated that peptides with a smaller MW (below 12 kDa) and a higher amount of hydrophobic amino acids aggregated more easily, resulting in the occurrence of precipitates and the relatively lower in vitro protein digestibility. This research contributes to the understanding of protein digestibility in whole legume-based diets, which in turn could aid in the development of new whole legume products and more efficient utilization of proteins.

Effect of Chinese-Yam-Based Emulsion Gel on Beef Emulsification Characteristics

Addressing the prevalent issue of excessive fat consumption in contemporary diets, a novel method has been devised for the preparation of an emulsion gel enriched with healthful fatty acids which possesses superior emulsification characteristics. This innovative approach aims to serve as a viable substitute for the fat content in beef mince. This paper aims to evaluate the effect of emulsion gels, formulated primarily with Chinese yam as the key ingredient, on the emulsification properties and microstructural characteristics of beef mince. The findings indicate that, when the proportion of fat substituted by the emulsion gel reaches 50%, the surface hydrophobicity of the beef mince attains a value of 37.34%, which approximates that of beef tallow. Furthermore, the water retention capacity of this formulation is significantly superior to that of the other test groups (p < 0.05). Additionally, when the fat replacement with emulsion gel is increased to 75%, the protein solubility is observed to be 22.85 mg/mL. As the quantity of emulsion gel increases, the gel structure of the beef mince undergoes a gradual densification. This alteration is accompanied by a statistically significant upward trend in the overall α-helix content (p < 0.05), whereas the β-turn angle exhibits an opposite trend and the β-sheet content demonstrates a biphasic pattern, initially increasing and subsequently decreasing. Notably, the random coil of the emulsion gel reaches its minimum when the fat content is at 50%, corresponding to a state of maximal stability in the beef mince. This study provides a basis for developing research into meat products with a healthier fat profile.

Impact of Simultaneous Nutrient Priming and Biopriming on Soybean Seed Quality and Health

In soybean production, numerous strategies are utilized to enhance seed quality and mitigate the effects of biotic and abiotic stressors. Zn-based nutrient priming has been shown to be effective for field crops, and biopriming is a strategy that is becoming increasingly important for sustainable agriculture. On the other hand, there is a lack of information about the effect of comprehensive nutrient priming and biopriming techniques on soybean seed quality and viability and seed health. This study was performed to assess the benefits of nutrient priming with Zn, biopriming with Bacillus megaterium and Bradyrhizobium japonicum (single and co-inoculation), and combination of nutrient priming and biopriming on the seed quality and viability, as well as seed infection caused by Alternaria spp. and Fusarium spp. Three different laboratory tests were employed: germination test, accelerated aging test, and seed health test. The results revealed that all tested priming treatments have a beneficial effect on seed germination, initial plant growth, and reduction of seed infection in normal and aged seeds. Additionally, comprehensive priming with Zn, Bacillus megaterium, and Bradyrhizobium japonicum reduced the occurrence of Alternaria spp. (-84% and -75%) and Fusarium spp. (-91% and -88%) on soybean seeds in the germination and accelerated aging tests, respectively, as compared to the control, which proved to be the most effective treatment in both optimal and stressful conditions.

Effect of Germination on the Digestion of Legume Proteins

As one of the main sources of plant protein, it is important to improve the protein digestibility of legumes. Faced with population growth and increasing environmental pressures, it is essential to find a green approach. Germination meets this requirement, and in the process of natural growth, some enzymes are activated to make dynamic changes in the protein itself; at the same time, other substances (especially anti-nutrient factors) can also be degraded by enzymes or their properties (water solubility, etc.), thereby reducing the binding with protein, and finally improving the protein digestibility of beans under the combined influence of these factors The whole process is low-carbon, environmentally friendly and safe. Therefore, this paper summarizes this process to provide a reference for the subsequent development of soybean functional food, especially the germination of soybean functional food.

Transformation profiles of the isoflavones in germinated soybean based on UPLC-DAD quantification and LC-QTOF-MS/MS confirmation

Germinated soybean is one kind of food and a medicine. In the actual process of producing a large amount of naturally germinated soybean, it is difficult to strictly control the germination process conditions. However, sprout length may be more suitable as the terminal judgment indicator for naturally germinated soybean. An UPLC-DAD method was developed and validated to explore the transformation profiles of soybean isoflavones in germinated yellow or black soybean with different sprout lengths. Moreover, an LC - QTOF-MS/MS method was used to avoid false positive results. The contents of daidzein, glycitein, and genistein almost reached their corresponding maximum values when the sprout length ranged from 1.0 cm to 1.5 cm (P < 0.05). Therefore, yellow soybean is suggested to be the processing raw material with higher contents of those isoflavones, and the optimal sprout length for germinated soybean may be in the range of 1.0-1.5 cm.

Refrigerated storage stimulates isoflavone and γ-aminobutyric acid accumulation in germinated soybeans

This study aims to investigate the quality changes of germinated soybeans during refrigerated storage (4 °C), with an emphasis on the stimulatory effect of refrigeration on their special functional compounds. After germinating for two days, germinated soybeans were stored at 4 °C for seven days, while the germinated soybeans stored at 25 °C served as control group. The results showed that refrigerated storage significantly affected the physiological changes in germinated soybeans. The weight loss rate, browning rate, malondialdehyde (MDA) content and H2O2 content all decreased dramatically during refrigerated storage compared to the control group. The total phenolic and total flavonoid contents of germinated soybeans under refrigeration exhibited a trend of increasing and then decreasing over time. Additionally, during refrigerated storage, the total isoflavone content reached a peak of 8.72 g/kg on the fifth day, in which the content of daidzein and glycitin increased by 45% and 49% respectively, when compared with the control group. Moreover, the content of γ-aminobutyric acid (GABA) peaked on the first day, and kept a high level during storage. In which, the refrigerated group was 2.35-, 2.88-, 1.67-fold respectively after storage for three to seven days. These results indicated that refrigeration stimulated the biosynthesis of isoflavones and GABA in germinated soybeans during storage. More importantly, there was a sequential difference in the timing of the stimulation of the two functional components under refrigeration.

Germination effects on the physicochemical properties and sensory profiles of velvet bean (Mucuna pruriens) and soybean tempe

Introduction

Previous studies have shown that the velvet bean, an indigenous legume in Indonesia, possesses high protein content and bioactive compounds. However, the utilization of velvet beans in tempe production remains underexplored.

Methods

This study aims to address this research gap by investigating the physicochemical properties and sensory profiles of tempe made from velvet beans, both individually and in combination with soybean. The study involved the production of tempe using germinated and non-germinated velvet bean, soybean, and a soy-velvet bean combination (61:39% ratio). Physicochemical analyses, including hardness, firmness, colour, antioxidant capacity, proximate, pH, and titratable acidity, were conducted. Hedonic rating and Check-All-That-Apply (CATA) tests were also performed to assess the sensory attributes of fresh and fried tempe.

Results and discussion

Germination treatment of velvet bean resulted in tempe with reduced hardness, firmness, antioxidant capacity, and pH levels compared to non-germinated velvet bean tempe. However, velvet bean tempe exhibited a darker colour, higher antioxidant capacity, higher pH levels, and lower titratable acidity compared to soybean tempe and soy-velvet bean combination tempe. The protein content in velvet bean tempe was found to be below the required threshold of 15%. Hedonic rating tests revealed that fresh and fried velvet bean tempe received lower scores than other samples. CATA tests identified specific sensory attributes essential for fresh and fried tempe, including beany aroma, white colour, nutty aroma, golden brown colour, solid and crunchy texture, umami taste, and nutty aftertaste. These findings provide valuable insights into the potential applications of velvet beans in tempe production and emphasize the significance of considering germination as a factor affecting the quality and sensory attributes of tempe.

Tempeh fermentation improves the nutritional and functional characteristics of Jack beans (Canavalia ensiformis (L.) DC)

The effect of two processing methods of Jack beans (i.e. cooked bean (CB) and cooked tempeh (CT)) on the in vitro digestibility of protein and starch, as well as the production of short chain fatty acids (SCFAs), γ-aminobutyric acid (GABA), and tryptophan (Trp) metabolites after in vitro colonic fermentation, was investigated. CT was obtained by fungal fermentation after cooking under acidic conditions. CT had significantly higher protein, lower digestible starch, lower total fiber, higher free phenolic compounds, and higher ash content compared to CB. CT exhibited better in vitro protein digestibility than CB and less glucose release during in vitro digestion than CB. A comparable concentration of total SCFAs and GABA was produced after in vitro fermentation of CB and CT, but CB produced more indole than CT, resulting in higher amounts of total Trp metabolites. In summary, our findings show that tempeh fermentation improves the nutritional quality of Jack beans and describe the impact of fermentation on the digestibility of nutrients and the formation of metabolites during colonic fermentation.

Exploring the binding mechanisms of thermally and ultrasonically induced molten globule-like β-lactoglobulin with heptanal as revealed by multi-spectroscopic techniques and molecular simulation

This work employed the model protein β-lactoglobulin (BLG) to investigate the contribution of microstructural changes to regulating the interaction patterns between protein and flavor compounds through employing computer simulation and multi-spectroscopic techniques. The formation of molten globule (MG) state-like protein during the conformational evolution of BLG, in response to ultrasonic (UC) and heat (HT) treatments, was revealed through multi-spectroscopic characterization. Differential MG structures were distinguished by variations in surface hydrophobicity and the microenvironment of tryptophan residues. Fluorescence quenching measurements indicated that the formation of MG enhanced the binding affinity of heptanal to protein. LC-MS/MS and NMR revealed the covalent bonding between heptanal and BLG formed by Michael addition and Schiff-base reactions, and MG-like BLG exhibited fewer chemical shift residues. Molecular docking and molecular dynamics simulation confirmed the synergistic involvement of hydrophobic interactions and hydrogen bonds in shaping BLG-heptanal complexes thus promoting the stability of BLG structures. These findings indicated that the production of BLG-heptanal complexes was driven synergistically by non-covalent and covalent bonds, and their interaction processes were influenced by processes-induced formation of MG potentially tuning the release and retention behaviors of flavor compounds.

Plant-based proteins: advances in their sources, digestive profiles in vitro and potential health benefits

Plant-based proteins (PBPs), which are environmentally friendly and sustainable sources of nutrition, can address the emerging challenges facing the global food supply due to the rapidly increasing population. PBPs have received much attention in recent decades as a result of high nutritional values, good functional properties, and potential health effects. This review aims to summarize the nutritional, functional and digestive profiles of PBPs, the health effects of their hydrolysates, as well as processing methods to improve the digestibility of PBPs. The diversity of plant protein sources plays an important role in improving the PBPs quality. Several types of models such as in vitro (the static and semi-dynamic INFOGEST) and in silico models have been proposed and used in simulating the digestion of PBPs. Processing methods including germination, fermentation, thermal and non-thermal treatment can be applied to improve the digestibility of PBPs. PBPs and their hydrolysates show potential health effects including antioxidant, anti-inflammatory, anti-diabetic, anti-hypertensive and anti-cancer activities. Based on the literature, diverse PBPs are ideal protein sources, and exhibit favorable digestive properties and health benefits that could be further improved by different processing technologies. Future research should explore the molecular mechanisms underlying the bioactivity of PBPs and their hydrolysates.

Different source of commercial soy protein isolates: Structural, compositional, and physicochemical characteristics in relation to protein functionalities

This study aimed to illustrate the relationship among physicochemical properties, subunit composition and protein functionalities in a broad collection of commercial soy protein isolates (SPIs) from China and the EU. The results indicated that SPIs had large variations in glycinin/β-conglycinin composition, protein denaturation, and water- and oil-binding capacity (WBC and OBC) and solubility. These SPIs could be roughly divided into pre-denatured SPI, partially hydrolyzed SPI, and less modified SPI. The pre-denatured SPI with high surface hydrophobicity and large particle sizes showed reduced WBC and OBC due to increased protein aggregation, and partially hydrolyzed SPI showed high protein solubility owing to the exposure of hydrophilic regions and reduction in molecular size. The processing-induced physicochemical changes played a pivotal role in determining protein functionalities, whereas subunit composition affected protein functionality less. Overall, this study highlighted the obvious difference in raw material quality of commercial SPI, and provided promising methods for SPI categorization.

How germination time affects protein hydrolysis of lupins during gastroduodenal digestion and generation of resistant bioactive peptides

Germination time is a critical factor that influences the digestibility and bioactivity of proteins in pulses. The objective was to understand the effect of sprouting time on protein hydrolysis (PH) and the release of bioactive peptides during digestion of lupin (Lupinus angustifolius L.) to provide recommendations on the optimum germination time for maximum nutritional and health benefits. Protein hydrolysis was monitored during germination and digestion by gel electrophoresis, size exclusion chromatography, and the analysis of soluble protein (SP), peptides (PEP), free amino acids (FAA) and free amino groups. The anti-inflammatory activity of intestinal digests was investigated in cell culture assays. Peptidomic and in silico analyses of intestinal digesta were conducted to identify digestion-resistant bioactive fragments. Germination time increased SP, PEP, and FAA. During digestion, the PH and release of small peptides was higher in sprouted lupin than control flour. Intestinal digests from sprouted lupin flour for 7 days exhibited the highest anti-inflammatory activity. In this sample, 11 potential bioactive peptides were identified. These findings open the exploration of novel food formulations based on sprouted lupins with higher protein digestibility and health-promoting potential.

Modification of Physiochemical and Techno-Functional Properties of Stink Bean (Parkia speciosa) by Germination and Hydrothermal Cooking Treatment

Stink bean, Parkia speciosa, is recognized as a significantly underutilized legume with versatile utility and diverse benefits. However, information on the impact of different processing methods, such as germination and hydrothermal cooking, is scarce on stink beans (SBs). Therefore, the current research aimed to explore the efficacy of germination (G) and hydrothermal cooking (HTC) on the physiochemical properties, proximate composition, techno-functional properties, and antioxidant potential of SB flour. Furthermore, Fourier transform infrared spectroscopy (FTIR) and field emission scanning electron microscopy (FESEM) were employed to assess structural and morphological changes. The results revealed that the physiochemical properties of SB were significantly enhanced through processing, with more pronounced improvements observed during germination. Additionally, SBG exhibited a significantly higher protein content and lower fat content compared to SBHTC and stink bean raw (SBR). Moreover, techno-functional properties such as color intensity, least gelation concentration, and pasting properties were significantly improved in SBG compared to SBHTC and SBR. FTIR analysis of SBG and SBHTC indicated structural modifications in the lipid, protein, and carbohydrate molecules. FESEM examination revealed morphological changes in SBG and SBHTC when compared to SBR. Importantly, SBG exhibited higher antioxidant activity and total phenolic content in comparison to SBHTC and SBR. Therefore, processed SB flour can be incorporated and utilized in product development, highlighting its potential as a plant-based protein source for protein-rich breakfast bars and cookies.

Use of natural biotechnological processes to modify the nutritional properties of bean-based and lentil-based beverages

The market for plant-based beverages (PBBs) is relatively new; hence, to enable its further development, it is important to use new raw materials and improve production technology. The use of natural biotechnological processes can diversify the segment of PBBs, which may offer products with better functionality than those available in the market. Therefore, the present study aimed to determine the effects of fermentation and germination on the nutritional properties of bean-based beverages (BBs) and lentil-based beverages (LBs). The applied processes significantly (p ≤ 0.05) influenced the characteristics of PBBs. Fermentation improved the antioxidant properties (e.g., by increasing the level of 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity by 2-6% and 3-7% for BBs and LBs, respectively) and modified the fatty acid (FA) profile of PBBs. This process increased the share of polyunsaturated FAs in the sn2 position in triacylglycerols, which may promote its absorption in the intestine. The simultaneous use of germination and fermentation was most effective in decreasing oligosaccharide content (< 1.55 mg/kg), which may reduce digestive discomfort after consuming PBBs. We recommend that the designing of innovative legume-based beverages should include the application of fermentation and germination to obtain products with probiotic bacteria and improved nutritional properties.

Development of technology for producing wheat bread enriched with soy ingredient

Nutritional supplements produced from soy and being rich in protein, fat and many other valuable substances have become a promising source of fortification of bakery products. This study aimed to develop a technology for producing wheat bread enriched with a protein-vitamin-mineral ingredient (PVMI) obtained from germinated soybeans. When kneading the dough, PVMI was added together with wheat flour and other dry components. Mathematical modeling of the wheat bread sensory evaluation showed the optimal content of PVMI in the recipe was 20% of the weight of wheat flour. As a result of the correlation-regression analysis, the most rational production characteristics for obtaining bread enriched with BVMI have been established. The amount of protein in the bread sample increased by 71.9%, dietary fiber - by 40.9%, vitamin E - by 34.7%, vitamin B1 - by 190%, vitamin B2 - by 80%, choline - by 186%. The fat quantity was 4.1 times more. At the same time, the total carbohydrate content decreased by 18.1% compared to the control sample. The improved chemical composition makes it possible to classify wheat bread with PVMI as an enriched food product.

Nutrient transfer and antioxidant effect of adzuki bean before and after GABA enrichment

In order to study the nutritional changes of γ-aminobutyric acid (GABA) enrichment in adzuki bean germination, vacuum combined with monosodium glutamate (MSG) was used as the germination stress of adzuki bean. The nutrient transfer before and after GABA enrichment in adzuki bean germination under vacuum combined with MSG stress were studied by means of chromatography and scanning electron microscope (SEM). The antioxidant activity and hypoglycemic effect of different solvent extracts before and after germination of adzuki bean were evaluated by experiments in vitro. The results showed that the nutritional characteristics of adzuki bean rich in GABA changed significantly (P < 0.05), the total fatty acids decreased significantly (P < 0.05), and the 21 amino acids detected increased significantly. After germination, the starch granules of adzuki bean became smaller and the surface was rough Germination stress significantly increased the antioxidant and hypoglycemic activities of the extracts from different solvents (P < 0.05), and the water extracts had the best effect on DPPH and ⋅OH radical scavenging rates of 88.52 and 83.56%, respectively. The results indicated that the germinated adzuki bean rich in GABA was more nutritious than the raw adzuki bean and had good antioxidant activity. It hoped to provide technical reference for rich food containing GABA.

The value of dietary plant protein in older people

PURPOSE OF REVIEW

The current review provides an update on recent research regarding plant-based protein and their nutritional quality for older people.

RECENT FINDINGS

There is growing evidence that plant-based proteins may be a valuable strategy for older people to prevent the health risks associated with consuming animal products and to promote better protein intake, as plant-based protein sources are rich in fibres and micronutrients. Although plant-based proteins are less anabolic than animal-derived proteins due to lower digestibility and deficiencies in some essential amino acids, several innovations in food processing and nutritional strategies have been developed to improve the quality of plant-based proteins. For example, the use of protein blends or green-processes as fermentation or germination could improve the nutritional qualities of plant-based foods that could be beneficial for older people, especially to prevent sarcopenia or metabolic disorders such as diabetes, obesity and cardiovascular diseases.

SUMMARY

The use of plant-based protein sources could help older people diversify their protein sources and more easily meet recommended nutritional intake. Recent literature highlights several health benefits associated with increased consumption of vegetable foods. However, their efficiency on postprandial muscle protein synthesis remains to be evaluated and long-term studies are needed.

Effect of Hydrothermal Cooking and Germination Treatment on Functional and Physicochemical Properties of Parkia timoriana Bean Flours: An Underexplored Legume Species of Parkia Genera

The present study was undertaken to analyze the impact of germination (NBG) and hydrothermal cooking (NBHTC) on the nutritional profile and physicochemical, functional and microstructural properties of Nitta bean (Parkia timoriana) (NBR) seeds. Results demonstrated that the highest crude protein and fat content could be found in NBG and NBHTC, whereas the ash content was significantly higher in NBG. Compared to NBHTC and NBR, NBG has higher emulsion capacity and stability, with values determined to be 58.33 ± 1.67 and 63.89 ± 2.67, respectively. In addition, the highest color intensity was also reported for NBG, followed by NBHTC and NBR. Likewise, NBG showed complete gel formation at a lower concentration (12 g/100 mL) than NBR flour (18 g/100 mL). Furthermore, structural changes in the lipid, protein, and carbohydrate molecules of NBG and NBHTC were evidenced by FTIR studies. Morphological changes were noticed in different samples during microscopic observations subjected to germination and hydrothermal treatment. In contrast to NBR and NBHTC, NBG showed the highest total polyphenol content, ORAC antioxidant, and DPPH radical scavenging activity, which demonstrated the potential utilization of Nitta bean flour as a natural plant-based protein source in food security product formulations.

The Impact of Dehulling and Germination on the Physiochemical, Protein Solubility and Water and Oil Holding Capacities of Yellow Eye Bean (Phaseolus vulgaris L.) Protein Concentrates

Pulse varieties including Yellow Eye (YE) beans (Phaseolus vulgaris L.) are a rich source of protein (~26.5%) that can be utilized to create value-added protein concentrates. Pre-treatments including dehulling and germination have been shown to be effective at improving the nutritional and functional properties of extracted protein concentrates. However, the composition and functionality of these protein concentrates can vary depending on the pre-treatments and the method of extraction used (salt vs. alkaline). Furthermore, little is known about the impact of combining these different processing methods on the properties of YE bean protein concentrates. The objective of this study was to evaluate how germination and dehulling pre-treatments individually and when combined influence protein extraction efficiency, physiochemical properties (surface hydrophobicity and intrinsic fluorescence), and the functionality (solubility, oil and water holding capacities) of salt and alkaline extracted protein concentrates. Compared to the salt extracted concentrates, the alkaline protein concentrates exhibited higher protein recovery yields (16–23% vs. 43–56%) respectively. Conversely, the salt extracted protein concentrates exhibited superior functional properties as observed by improved water holding capacities and less variation in their solubilities at different pH values (4 to 10). When the pre-treatments were combined, the salt extracted concentrates exhibited improved extraction efficiencies and improved hydrophobicity and intrinsic fluorescence, whereas the opposite trend was observed in the alkaline protein concentrates. These observations were attributed to differences in the protein content and composition of the salt vs. alkaline protein concentrates. Overall, these findings suggest that dehulling and germination are potential processing methods that may be used to improve the physiochemical characteristics of salt extracted protein concentrates from yellow eye beans. Future research may investigate the potential application of these ingredients in different food formulations.

Effects of heat treatment on protein molecular structure and in vitro digestion in whole soybeans with different moisture content

The effects of heat treatment on protein structure and in vitro digestibility in whole soybeans with different moisture content (10.68%, 29.70%, 46.29%, and 62.05% wet basis) were investigated. Scanning electronic microscopy presented that thermal treatment destroyed the subcellular structure of soybean seeds and resulted in formation of protein aggregates. When β-conglycinin (7S) was heat-denatured, the protein aggregates were maintained mainly by hydrogen bonds and hydrophobic interactions (non-covalent) for each moisture content. Also, the decrease of the protein solubility and increase of in vitro digestibility were observed. However, when glycinin (11S) was denatured in soybeans with 10.68% and 29.70% moisture content, the insoluble and indigestible protein aggregates with protein oxidation-induced crosslinking and high content of β-sheet were presented; in contrast, for 46.29% and 62.05% moisture content, mild protein oxidation, low content of β-sheet, non-covalent interactions and increased protein digestibility were shown. Non-covalent interactions were shown a positive correlation with gastrointestinal digestibility (r = 0.59, p < 0.05). Meanwhile, protein oxidation or β-sheet content was significantly negatively correlated with in vitro protein digestibility (r = -0.69 and -0.61, respectively, p < 0.05). Protein structure rather than solubility contributed to difference of in vitro digestibility. The optimum thermal conditions to obtain high-quality digestible protein in whole soybeans are 160 °C for 10.68%, 145 °C for 29.70%, 160 °C for 46.29% and 115 °C/140 °C for 62.05% moisture content.

Lentil and Fava Bean With Contrasting Germination Kinetics: A Focus on Digestion of Proteins and Bioactivity of Resistant Peptides

Germination offers advantages to improve legume protein digestibility as it disintegrates seed structure and hydrolyzes proteins and anti-nutrients. Seed permeability (related to polyphenol content of seed coats) is an important factor affecting the duration of seed germination and its impact on protein digestibility and bioactivity. The objective was to compare the effect of seed germination on protease activity, structure, and proteolysis of four selected legumes with contrasting seed coat polyphenol profiles (gray zero-tannin lentil [GZL], beluga lentil [BL], and dehulled red lentil [DL]; and zero tannin/low vicine-convicine fava bean [ZF]). Protein hydrolysis was characterized during germination and digestion with respect to proteins, peptides, and free amino acids (FAAs). In vitro antihypertensive and antioxidant activities of digests were investigated, and the peptidomic characterization [high-performance liquid chromatography coupled to tandem mass spectrometry (HPLC-MS/MS)] and identification of bioactive fragments in intestinal digests were performed. Regardless of the seed type, germination increased protease activity and reduced the levels of phytic acid, trypsin inhibitors, and tannins (only in BL). A significant proteolysis of the 7S and 11S globulins and a concomitant increase of peptides and FAAs were observed in all sprouted legumes. Digestion kinetics in sprouts revealed a faster generation of FAAs and peptides than in dry seeds, with changes being more evident for DL, associated with a faster imbibition, germination, and sprout growth. In contrast, BL sprouts showed the lowest protein digestibility, likely due to a lower protease activity, seed structure disintegration, and higher anti-nutrient levels in comparison to GZL, DL, and ZF. Moreover, the digestion of sprouts resulted in a higher number of resistant peptides in DL and ZF that matched with previously reported bioactive sequences, suggesting a promising health potential of legume sprouts that was confirmed in vitro. The results suggested that the germination process improved protein digestibility and the health-promoting potential of lentil and fava bean proteins although these changes were more evident in DL due to its rapid imbibition, faster germination, and sprout development. This study will provide important information for either plant breeders to develop legume varieties with permeable seed coats or food producers that could use dehulled seeds for efficient production of sprouts as sustainable food sources of plant proteins with improved nutritional and healthy properties.