Soy Protein: Molecular Structure Revisited and Recent Advances in Processing Technologies

Acceleration of soy protein amyloid fibrils formation: Homologous seeding mechanism

Adding prefabricated seeds to the fibril formation solution can accelerate the process of fibrillation. Various variants of soy protein amyloid fibrils (SAFs) (oligomers, short fibrils, long fibrils and mature long fibrils) were employed as seeds (OL, SF, LF and MLF). These fibrils were then introduced into a solution using a homologous seeding approach. We conducted a comprehensive analysis of various aspects, including morphological characteristics, surface hydrophobicity, secondary structures, fibril conversion rate and rheological properties. The results indicated that the addition of seeds, particularly those composed of longer and more mature fibrils, played a pivotal role in accelerating the formation of rigid and extended fibrils. Mature long fibrils as seeds can shorten the formation time of long fibrils (fibril length ≥ 600 nm) from 12 to 3 h. The seeding significantly shortens the formation time of SAFs, meanwhile, this study provides insights into the intricate dynamics of amyloid fibril at homologous seeding.

Gelling ability and gel structure of soy protein isolate influenced by heating in the presence of various acids

This study investigated the influence of acids on gelation of soy protein isolate (SPI) under heating. Specifically, the SPI solution was acidified to pH 2.5 using hydrochloric acid (HA), acetic acid (AA), tartaric acid (TA) and citric acid (CA), respectively, and then heated at 85 °C. It was found that the SPI gel with the anisotropic structure was formed, which suggested that the gel resulted from the organized arrangement of the SPI fibril. Subsequently, it was confirmed by several techniques such as atomic force microscopy that the above acidic-thermal treatment induced fibrillation of SPI. Furthermore, the ability of these acids to promote gelation and fibrillation of SPI was in the order of CA > TA > HA > AA. In summary, these results suggested that heating at pH 2.5 resulted in SPI fibrillation, thus promoting SPI gelation, and the acidity regulator type had a profound effect.

Enhancement of soy protein functionality by conjugation or complexation with polysaccharides or polyphenols: A review

Soy proteins have good nutritional quality and exhibit a range of useful functional attributes, making them a viable option for replacing animal proteins in the development of more sustainable and eco-friendly plant-based food products. Nevertheless, soy proteins are prone to denaturation and/or aggregation under conditions they encounter in some food and beverage products (including certain pH, ionic, and thermal conditions), which adversely impact their functional performance. This problem can often be overcome by covalently (conjugation) or noncovalently (complexation) linking the soy proteins to polysaccharides or polyphenols, thereby expanding their application scope. Compared to soy proteins alone, these conjugates or complexes exhibit enhanced technofunctional performance, including improved solubility, emulsification, foaming, gelling, antimicrobial properties, and antioxidant capacities. Conjugates are typically more stable than complexes, which may be an advantage for some food applications. However, complexes do not require additional regulatory approval, which makes them more suitable for most food applications. This review aims to comprehensively examine the enhancement of soy protein functionality through conjugation or complexation with polysaccharides or polyphenols. The research focuses on how these modifications enhance solubility, emulsification potential, foaming, gelling, and antioxidant properties, reduce the allergenicity of soy proteins, and enable their potential applications in plant-based food development, 3D food printing, fat substitutes, functional food carriers, and hypoallergenic foods.

The structure-function relationships and techno-functions of β-conglycinin

β-conglycinin (β-CG) is a prominent storage protein belonging to the globulin family in soybean (Glycine max) seeds. Along with other soybean proteins, it serves as an important source of essential amino acids and high-quality nutrition. However, the digestibility and nutritional value of β-CG are key factors affecting the nutritional profile of soy-based foods. The heterotrimeric, secondary, and quaternary structures of β-CG, particularly the spatial arrangement of its α, α', and β subunits, influence its functional properties. Considering these aspects, β-CG emerges as a significant protein with diverse applications in the food and health sectors. Therefore, this review explores β-CG's composition, structure, function, health implications, and industrial uses. Salient discussions are presented on its molecular structure, nutrition, digestibility, allergenicity, and techno-functions including emulsification, solubility, gelling, and structure-function complexities. Overall, the multifaceted potential of β-CG in the healthcare sector and the food industry is evident.

Structural characteristics, techno-functionalities, innovation applications and future prospects of soybean β-conglycinin/glycinin: a comprehensive review

The structural molecules and conformational variations of soybean β-conglycinin/glycinin are crucial in defining the characteristics of protein-based foods. Recently, significant attention has been focused on the characteristics of soybean β-conglycinin/glycinin across various fields, particularly their structure and application. The research contributes to expanding the application fields of soybean protein-related component in food industry. This research generally concerned on, but not limited to, the novel substitution of animal-originated foods based on globulins and the deeper precising protein nutrition support. Furthermore, the innovative applications and future development of soybean globulins are presented, focusing on plant-based substitutes and advanced materials. This paper provides a comprehensive review of soybean β-conglycinin/glycinin, focusing on structural characteristics, techno-functionalities, innovation applications, and future prospects, supported by diverse citation and analyses. Additionally, the article introduces various methods for modifying soybean globulins, including physical, chemical, and biological treatments. Furthermore, the innovative applications and future development of soybean globulins are presented, focusing on plant-based substitutes and advanced materials. Despite extensive discussion on globulin applications in diverse food forms, the discourse on their flavor and safety is insufficient. Addressing these limitations is essential for a comprehensive understanding and effective utilization of soybean globulins.

Protein blend extrusion: Crafting meat analogues with varied textural structures and characteristics

With an increasing emphasis on health and environmental consciousness, there is a growing inclination toward plant protein-based meat substitutes as viable alternatives to animal meat. In the pursuit of creating diverse and functional plant protein-based substitutes, innovative plant proteins have been introduced in conjunction with soy protein isolate (SPI), encompassing pea protein isolate (PPI), rice bran protein (RBP), fava bean protein isolate (FPI), and spirulina protein isolate (SPPI). Notably, SPI-WG extrudates and SPI-PPI extrudates exhibited superior fiber structures (fiber degrees were 1.72 and 1.88, respectively), with coarse fibers in SPI-WG extrudates and fine, dense fibers in SPI-PPI extrudates. The addition of RBP, FPI and SPPI had minimal effect on fiber structure. Fresh SPI-FPI displayed the slowest rate of water loss, losing about 7.11% of their total weight in 5 h. Different plant proteins can be selected for the preparation of plant protein-based meat substitutes according to practical needs.

Tailoring soy protein/corn zein mixture by limited enzymatic hydrolysis to improve digestibility and functionality

This study aimed to modify plant protein mixture to improve their functionality and digestibility by limited hydrolysis. Soy protein isolate and corn zein were mixed at the ratio of 5:1 (w/w), followed by limited hydrolysis using papain from 15 to 30 min. The structural characteristics, in vitro digestibility, and functional properties were evaluated. Also, DPPH radical scavenging activity was determined. The results indicated that the molecular weight of different modified samples was largely reduced by limited hydrolysis, and the proportion of random coil was significantly increased. Furthermore, the solubility, foaming, emulsifying and water-holding capacity of hydrolyzed protein mixture were significantly improved, which were close to those of whey protein isolate. In vitro digestibility after 30-min limited hydrolysis was remarkably elevated. In addition, the hydrolyzed protein mixture exhibited a higher antioxidant activity than those of untreated proteins. Overall, limited hydrolysis of protein mixture led to improved digestibility, functionality and antioxidant activity.

Effect of protease hydrolysis on the structure of acidic heating-induced soy protein amyloid fibrils

The effectiveness of using amyloid fibrillation to improve the functional qualities of soy protein had drawn growing attention. However, the relationship between protein subunits and the structural polymorphism of soy protein-derived amyloid fibrils (SAFs) was not yet completely understood. In this study, soy protein subunits were hydrolyzed to different degrees according to the different action sites of different proteases (Pepsin, Papain and Alcalase). The impact of subunits on the amyloid fibrillation of soy protein was investigated through various techniques including atomic force microscopy, thioflavin T fluorescence, 1-anililo-naphthalene-8-sulfonate, and Fourier transform infrared spectrometer. The findings showed that the α and α' subunits were associated with the formation of fibril branch chains. The degree of hydrolysis of β subunits was found to be proportional to the number of fibrils. The presence of the 11S component was identified as a necessary condition for the formation of long-rigid fibrils. Furthermore, enzymatic hydrolysis unfolded the protein structure, exposing hydrophobic groups, loosening the protein structure, and altering the proportion of parallel and antiparallel β-sheet structures. This promoted the formation of amyloid fibrils and accelerated the development of stable SAFs gel. This study advances the knowledge of the function of subunits in amyloid fibrillation.

Synergistic enhancement of anthocyanin stability and techno-functionality of colored wheat during the steamed bread processing by selectively hydrolyzed soy protein

To improve the stability of anthocyanins and techno-functionality of purple and blue wheat, the selectively hydrolyzed soy protein (reduced glycinin, RG) and β-conglycinin (7S) were prepared and their enhanced effects were comparatively investigated. The anthocyanins in purple wheat showed higher stability compared to that of the blue wheat during breadmaking. The cyanidin-3-O-glucoside and cyanidin-3-O-rutincoside in purple wheat and delphinidin-3-O-rutinoside and delphinidin-3-O-glucoside in blue wheat were better preserved by RG. Addition of RG and 7S enhanced the quality of steamed bread made from colored and common wheat, with RG exhibited a more prominent effect. RG and 7S suppressed the gelatinization of starch and improved the thermal stability. Both RG and 7S promoted the unfolding process of gluten proteins and facilitated the subsequent crosslinking of glutenins and gliadins by disulfide bonds. Polymerization of α- and γ-gliadin into glutenin were more evidently promoted by RG, which contributed to the improved steamed bread quality.

Exogenous Amyloid Fibrils Can Cause Significant Upregulation of Neurodegenerative Disease Proteins

Neurodegenerative diseases, such as Alzheimer's disease and Parkinson's disease, are associated with the formation of amyloid fibrils. In familial cases, the mutant causative genes accentuate disease progression through overexpression or misfolding of amyloidogenic proteins. Besides, considerable amyloidosis cases arise from external factors, but their origin and mechanisms are not yet fully understood. Herein, we found that amyloid fibrils generated from egg and milk proteins, in addition to their nutritional effects to intestinal cells, can selectively reduce the viability of nervous cells as well as pancreatic islet cells. In contrast, soy protein amyloid fibrils lacked cytotoxicity to the aforementioned cells. This protein source and cell type-dependent cytotoxicity are demonstrated to be associated with the significant upregulation of amyloidogenic proteins. The finding was also confirmed by the vein injection of beta-lactoglobulin fibrils to mice, exhibiting the pronounced upregulations of amyloid beta1-42 (Aβ1-42) and islet amyloid polypeptide in vivo. The study therefore provides insight into the health implications of exogenous amyloid fibrils.

Toward Diverse Plant Proteins for Food Innovation

This review highlights the development of plant proteins from a wide variety of sources, as most of the research and development efforts to date have been limited to a few sources including soy, chickpea, wheat, and pea. The native structure of plant proteins during production and their impact on food colloids including emulsions, foams, and gels are considered in relation to their fundamental properties, while highlighting the recent developments in the production and processing technologies with regard to their impacts on the molecular properties and aggregation of the proteins. The ability to quantify structural, morphological, and rheological properties can provide a better understanding of the roles of plant proteins in food systems. The applications of plant proteins as dairy and meat alternatives are discussed from the perspective of food structure formation. Future directions on the processing of plant proteins and potential applications are outlined to encourage the generation of more diverse plant-based products.

Soy proteins modified using cavitation jet technology

Soy proteins are seen as a promising alternative food source for meat with environmentally friendly properties. The problem is that the functional properties of soy proteins do not meet the needs of the food industry, and some existing modification technologies have adverse effects. Recently, cavitation jet technology (CJT) has been studied because it generates high heat, high pressure, strong shear and strong shock waves. This review summarizes the history and mechanism of cavitation jets. The energy generated during the cavitation jet process can open molecular structures, and the shock waves and microjets generated can pulverize the materials by erosion. The impact of the CJT on the morphology, structure, and functionality of soy proteins is discussed. The impact of combining CJT with other techniques on the production of soy proteins was also reviewed. The modification of proteins using two or more methods with complementary strengths, avoiding the disadvantages of certain techniques, makes the modification of proteins more effective. One of the most prominent effects is the combined treatment of cavitation jets with physical techniques. Finally, the review provides a comprehensive analysis of the application of modified soy proteins in the food industry and highlights promising avenues for future research.

Effect of transglutaminase on gelation and functional proteins of mung bean protein isolate

This study aimed to improve mung bean protein's gelation qualities via microbial transglutaminase (mTGase) cross-linking. The mTGase treatment significantly improved gel hardness and storage modulus (G') at higher enzyme levels (2 IU/g), peaking hardness at 3 h. The scanning electron microscopy imaging demonstrated more cross-linked structures at 2 IU/g, evolving into a dense network by 3 h. The water-holding capacity for mTGase-treated samples (2 IU/g, 3 h, 55 °C) tripled to 3.77 ± 0.06 g/g versus control (1.24 ± 0.02 g/g), alongside a 15 % decrease in zeta potential (-30.84 ± 0.901 mV versus control's -26.63 ± 0.497 mV) and an increase in emulsifying activity index to 4.519 ± 0.004 m2/g from 3.79 ± 0.01 m2/g (control). The confocal images showed a more uniform lipid droplet distribution in mTGase-treated samples, suggesting enhanced emulsifying activity. Thus, mTGase treatment significantly improved gel strength and emulsifying properties, making it ideal for plant-based seafood products.

Complexes of soybean protein fibrils and chlorogenic acid: Interaction mechanism and antibacterial activity

This study explored the mechanism of interaction between chlorogenic acid (CA) and protein fibrils (PF) as well as the effects of varying the CA/PF concentration ratio on antibacterial activity. Analysis of various parameters, such as ζ-potential, thioflavin T fluorescence intensity, surface hydrophobicity, and free sulfhydryl groups, revealed that the interaction between PF and CA altered the structure of PF. Fluorescence analysis revealed that hydrogen bonding and hydrophobic interactions were the primary interaction forces causing conformational rearrangement, resulting in a shorter, more flexible, and thicker fibril structure, as observed through transmission electron microscopy. Fourier-transform infrared spectroscopy, small-angle X-ray scattering, and X-ray diffraction analyses revealed that the characteristic fibril structure was destroyed when the CA/PF ratio exceeded 0.05. Notably, the CA-PF complexes inhibited the growth of Escherichia coli and Staphylococcus aureus and also exhibited antioxidant activity. Overall, this study expands the application prospects of CA and PF in the food industry.

Effects of zein extractions on the structural properties of SPI-zein composite gels: Implications for gluten-free plant-based products

The growing global interest in physical and environmental health has led to the development of plant-based products. Although soy protein and wheat gluten are commonly utilized, concerns regarding gluten-related health issues have driven exploration into alternative proteins. Zein has emerged as a promising option. This research investigated the impact of extraction methods on zein characteristics and the structures of SPI-zein composite gels. Different extraction methods yielded zein with protein contents ranging from 48.12 % to 64.34 %. Ethanol-extracted Z1 and Z3, obtained at different pH conditions, exhibited zeta potential of -3.25 and 5.43 mV, respectively. They displayed similar characteristics to commercial zein and interacted comparably in composite gels. Conversely, alkaline-extracted Z2 had a zeta potential of -2.37 mV and formed distinct gels when combined with SPI. These results indicated that extraction methods influence zein behaviour in composite gels, offering possibilities for tailored formulations and expanding zein's applications, particularly in gluten-free plant-based products.

Synergistic effect of gellan gum and guar gum on improving the foaming properties of soy protein isolate-based complexes: Interaction mechanism and interfacial behavior

Interactions among multi-component play a critical role in modulating the foaming properties of aerated foods. This study evaluated the mechanisms of synergistic improvement of gellan gum (GEG) and guar gum (GUG) on the foaming properties of soy protein isolate (SPI)-based complex. The results showed that the GEG/GUG ratio was closely related to the intermolecular interactions of SPI-based ternary complex and the dynamical changing of its foaming properties. The SPI/GEG/GUG ternary complex with a GEG/GUG ratio of 2/3 exhibited the highest foamability (195 %) and comparable foam stability (99.17 %), which were 32.95 % and 2.99 % higher than that of SPI/GEG binary complex. At this ratio, GUG promoted the interactions between SPI and GEG, and bound to complex's surface through hydrogen bonding, resulting in the increase of particle size and surface charge, and the decrease of surface hydrophobicity. Although this reduced the diffusion of complex onto the air/water interface, it increased permeation rate and molecular rearrangement behavior, which were the potential mechanisms to improve the foaming properties. Additionally, the synergistic effect of GEG and GUG also enhanced the elastic strength and solid characteristics of foam systems. This study provided a theoretical guidance for the targeted modulation of foaming properties of multi-component aerated foods.

Advancements in plant based meat analogs enhancing sensory and nutritional attributes

The burgeoning demand for plant-based meat analogs (PBMAs) stems from environmental, health, and ethical concerns, yet replicating the sensory attributes of animal meat remains challenging. This comprehensive review explores recent innovations in PBMA ingredients and methodologies, emphasizing advancements in texture, flavor, and nutritional profiles. It chronicles the transition from soy-based first-generation products to more diversified second- and third-generation PBMAs, showcasing the utilization of various plant proteins and advanced processing techniques to enrich sensory experiences. The review underscores the crucial role of proteins, polysaccharides, and fats in mimicking meat's texture and flavor and emphasizes research on new plant-based sources to improve product quality. Addressing challenges like production costs, taste, texture, and nutritional adequacy is vital for enhancing consumer acceptance and fostering a more sustainable food system.

Plant-based proteins: clinical and technological importance

Healthy and sustainable diets have seen a surge in popularity in recent years, driven by a desire to consume foods that not only help health but also have a favorable influence on the environment, such as plant-based proteins. This has created controversy because plant-based proteins may not always contain all the amino acids required by the organism. However, protein extraction methods have been developed due to technological advancements to boost their nutritional worth. Furthermore, certain chemicals, such as bioactive peptides, have been identified and linked to favorable health effects. As a result, the current analysis focuses on the primary plant-based protein sources, their chemical composition, and the molecular mechanism activated by the amino acid types of present. It also discusses plant protein extraction techniques, bioactive substances derived from these sources, product development using plant protein, and the therapeutic benefits of these plant-based proteins in clinical research.

Fabrication of soy protein nanoparticles based on metal-phenolic networks for stabilization of nano-emulsions delivery system

The use of soy protein isolate (SPI) nanoparticles as a stabilizer in nano-emulsion systems has garnered significant interest. While metal-phenolic networks (MPNs) have been explored for their multifunctional surface modification capabilities, their integration with food protein-based delivery systems remains less explored. In this study, we attempt to develop a novel strategy to encapsulate cinnamaldehyde using MPNs (EGCG-Fe3+) with self-assembling soy protein nanoparticles (SE-Fe NPs) as a stabilizer for nano-emulsions. UV, Raman, and X-ray photoelectron spectroscopy analyses demonstrated that SE-Fe NPs were generated through metal-phenolic coordination and covalent interactions. SE-Fe NPs had a narrower particle size distribution and enhanced radical scavenging (up to 3.35-fold), as well as thermal stability. Furthermore, the smaller droplet size, higher modulus, higher cinnamaldehyde encapsulation efficiency (from 63.5% to 84.2%), and improved bio-accessibility of SE-Fe NPs stabilized nano-emulsions delivery system demonstrated in this study shows promising future applications in the food industry.

Establishing a novel ternary complex of soybean protein isolated-tannic acid-magnesium ion and its properties

A ternary complex composed of soybean protein isolated (SPI), tannic acid (TA) and magnesium ion (M) was established to enhance the capability of protein carriers for TA delivery. SPI was firstly covalently bind with TA (TA-SPI) and then M was employed to form the ternary complex (M-TA-SPI). Their structures, gel and digestion properties were further investigated. TA was observed to covalently bind with SPI. TA-SPI and M-TA-SPI complexes showed different molecule size and spatial structures after binding with M and TA. The increasing of TA amount changed the intramolecular interactions, microstructure and texture properties of M-TA-SPI gels. Compared with TA-SPI, M retarded the gastric digestion of M-TA-SPI and caused higher TA release amount in intestinal tract. In this study, M-TA-SPI was determined to be a good carrier to protect and release TA in gastrointestinal digestion. This kind of complex may have potential applications for loading polyphenols in nutraceuticals.

A Comprehensive Review on Harnessing Soy Proteins in the Manufacture of Healthy Foods through Extrusion

The global development of livestock production systems, accelerated by the growing demand for animal products, has greatly contributed to land-use change, greenhouse gas emissions, and pollution of the local environment. Further, excessive consumption of animal products has been linked with cardiovascular diseases, digestive system diseases, diabetes, and cancer. On the other hand, snacks, pasta, and bread available on the market are made from wheat, fat, salt, and sugar, which contribute to the risk of cardiovascular diseases. To counter these issues, a range of plant protein-based food products have been developed using different processing techniques, such as extrusion. Given the easy scalability, low cost of extrusion technology, and health benefits of soy proteins, this review focuses on the extrusion of soy protein and the potential application of soy protein-based extrudates in the manufacture of healthy, nutritious, and sustainable meat analogs, snacks, pasta products, and breakfast cereals. This review discusses the addition of soy protein to reformulate hypercaloric foods through extrusion technology. It also explores physical and chemical changes of soy proteins/soy protein blends during low and high moisture extrusion. Hydrogen bonds, disulfide bonds, and hydrophobic interactions influence the properties of the extrudates. Adding soy protein to snacks, pasta, breakfast cereals, and meat analogs affects their nutritional value, physicochemical properties, and sensory characteristics. The use of soy proteins in the production of low-calorie food could be an excellent opportunity for the future development of the soybean processing industry.

Impact of pilot-scale microfluidization on soybean protein structure in powder and solution

The effect of microfluidization treatment on the primary, secondary, and tertiary structure of soybean protein isolate (SPI) was investigated. The samples were treated with and without controlling the temperature and circulated in the system 1, 3, and 5 times at high pressure (137 MPa). Then, the treated samples were freeze-dried and reconstituted in water to check the impact of the microfluidization on two different states: powder and solution. Regarding the primary structure, the SDS-PAGE analysis under reducing conditions showed that the protein bands remained unchanged when exposed to microfluidization treatment. When the temperature was controlled for the samples in their powder state, a significant decrease in the quantities of β-sheet and random coil and a slight reduction in α-helix content was noticed. The observed decrease in β-sheet and the increase in β-turns in treated samples indicated that microfluidization may lead to protein unfolding, opening the hydrophobic regions. Additionally, a lower amount of α-helix suggests a higher protein flexibility. After reconstitution in water, a significant difference was observed only in α-helix, β-sheet and β-turn. Related to the tertiary structure, microfluidization increases the surface hydrophobicity. Among all the conditions tested, the samples where the temperature is controlled seem the most suitable.

Proteins from Legumes, Cereals, and Pseudo-Cereals: Composition, Modification, Bioactivities, and Applications

This review presents a comprehensive analysis of plant-based proteins from soybeans, pulses, cereals, and pseudo-cereals by examining their structural properties, modification techniques, bioactivities, and applicability in food systems. It addresses the critical need for a proper utilization strategy of proteins from various plant sources amidst the rising environmental footprint of animal protein production. The inherent composition diversity among plant proteins, their nutritional profiles, digestibility, environmental impacts, and consumer acceptance are compared. The innovative modification techniques to enhance the functional properties of plant proteins are also discussed. The review also investigates the bioactive properties of plant proteins, including their antioxidant, antimicrobial, and antitumoral activities, and their role in developing meat analogs, dairy alternatives, baked goods, and 3D-printed foods. It underscores the consideration parameters of using plant proteins as sustainable, nutritious, and functional ingredients and advocates for research to overcome sensory and functional challenges for improved consumer acceptance and marketability.

Microencapsule delivery systems of functional substances for precision nutrition

Microencapsulation, a typical core-shell structure technology, encapsulates functional active ingredients for protection, controlled release, and targeted delivery. In precise nutrition, the focus is on utilizing microcapsule delivery systems for personalized dietary supplements and disease intervention. This chapter outlines the morphological structure of microcapsules, common wall materials, and preparation techniques. It discusses the characteristics of different hydrophilic and lipophilic functional factors and their function as dietary supplements. The role of microencapsulation on the controlled release, odor masking, and enhanced bioavailability of functional factors is explored. Additionally, the application of microcapsule delivery systems in nutritional interventions for diseases like inflammatory bowel disease, alcoholic/fatty liver disease, diabetes, and cancer is introduced in detail. Lastly, the chapter proposes the future developments of anticipation in responsive wall materials for precise nutrition interventions, including both challenges and opportunities.

Study on the quality of soybean proteins fermented by Bacillus subtilis BSNK-5: Insights into nutritional, functional, safety, and flavor properties

Microbial fermentation emerges as a promising strategy to elevate the quality of soybean proteins in food industry. This study conducted a comprehensive assessment of the biotransformation of four types of soybean proteins by Bacillus subtilis BSNK-5, a proteinase-rich bacterium. BSNK-5 had good adaptability to each protein. Soluble protein, peptides and free amino acids increased in fermented soybean proteins (FSPs) and dominant after 48-84 h fermentation, enhancing nutritional value. Extensive proteolysis of BSNK-5 also improved antioxidant and antihypertensive activities, reaching peak level after 48 h fermentation. Furthermore, excessive proteolysis effectively enhanced the generation of beneficial spermidine without producing toxic histamine after fermentation, and formed the flavor profile with 56 volatiles in 48 h FSPs. Further degradation of amino acids showed a positive correlation with off-flavors, particularly the enrichment of 3-methylbutanoic acid. These findings establish a theoretical foundation for regulating moderate fermentation by BSNK-5 to enabling the high-value utilization of soybean protein.

Research Progress on the Extraction and Purification of Anthocyanins and Their Interactions with Proteins

Anthocyanins, as the most critical water-soluble pigments in nature, are widely present in roots, stems, leaves, flowers, fruits, and fruit peels. Many studies have indicated that anthocyanins exhibit various biological activities including antioxidant, anti-inflammatory, anti-tumor, hypoglycemic, vision protection, and anti-aging. Hence, anthocyanins are widely used in food, medicine, and cosmetics. The green and efficient extraction and purification of anthocyanins are an important prerequisite for their further development and utilization. However, the poor stability and low bioavailability of anthocyanins limit their application. Protein, one of the three essential nutrients for the human body, has good biocompatibility and biodegradability. Proteins are commonly used in food processing, but their functional properties need to be improved. Notably, anthocyanins can interact with proteins through covalent and non-covalent means during food processing, which can effectively improve the stability of anthocyanins and enhance their bioavailability. Moreover, the interactions between proteins and anthocyanins can also improve the functional characteristics and enhance the nutritional quality of proteins. Hence, this article systematically reviews the extraction and purification methods for anthocyanins. Moreover, this review also systematically summarizes the effect of the interactions between anthocyanins and proteins on the bioavailability of anthocyanins and their impact on protein properties. Furthermore, we also introduce the application of the interaction between anthocyanins and proteins. The findings can provide a theoretical reference for the application of anthocyanins and proteins in food deep processing.

Effect of Thermal Treatment on Gelling and Emulsifying Properties of Soy β-Conglycinin and Glycinin

This study investigated the impact of different preheat treatments on the emulsifying and gel textural properties of soy protein with varying 11S/7S ratios. A mixture of 7S and 11S globulins, obtained from defatted soybean meal, was prepared at different ratios. The mixed proteins were subjected to preheating (75 °C, 85 °C, and 95 °C for 5 min) or non-preheating, followed by spray drying or non-spray drying. The solubility of protein mixtures rich in the 7S fraction tended to decrease significantly after heating at 85 °C, while protein mixtures rich in the 11S fraction showed a significant decrease after heating at 95 °C. Surprisingly, the emulsion stability index (ESI) of protein mixtures rich in the 7S fraction significantly improved twofold during processing at 75 °C. This study revealed a negative correlation between the emulsifying ability of soy protein and the 11S/7S ratio. For protein mixtures rich in either the 7S or the 11S fractions, gelling proprieties as well as emulsion activity index (EAI) and ESI showed no significant changes after spray drying; however, surface hydrophobicity was significantly enhanced following heating at 85 °C post-spray drying treatment. These findings provide insights into the alterations in gelling and emulsifying properties during various heating processes, offering great potential for producing soy protein ingredients with enhanced emulsifying ability and gelling property. They also contribute to establishing a theoretical basis for the standardized production of soy protein isolate with specific functional characteristics.

High-Moisture Extrusion of Plant Proteins: Fundamentals of Texturization and Applications

The growing demand for sustainable and healthy food alternatives has led to a significant increase in interest in plant-based protein products. Among the various techniques used in creating meat analogs, high-moisture extrusion (HME) stands out as a promising technology for developing plant-based protein products that possess desirable texture and mouthfeel. During the extrusion process, plant proteins undergo a state transition, causing their rheological properties to change, thereby influencing the quality of the final extrudates. This review aims to delve into the fundamental aspects of texturizing plant proteins using HME, with a specific focus on the rheological behavior exhibited by these proteins throughout the process. Additionally, the review explores the future of HME from the perspective of novel raw materials and technologies. In summary, the objective of this review is to provide a comprehensive understanding of the potential of HME technology in the development of sustainable and nutritious plant-based protein products.

Dietary supplements: clinical cholesterol-lowering efficacy and potential mechanisms of action

This review aims to analyse the efficacy of dietary supplements in reducing plasma cholesterol levels. Focusing on evidence from meta-analyses of randomised controlled clinical trials, with an emphasis on potential mechanisms of action as supported by human, animal, and cell studies. Certain dietary supplements including phytosterols, berberine, viscous soluble dietary fibres, garlic supplements, soy protein, specific probiotic strains, and certain polyphenol extracts could significantly reduce plasma total and low-density lipoprotein (LDL) cholesterol levels by 3-25% in hypercholesterolemic patients depending on the type of supplement. They tended to be more effective in reducing plasma LDL cholesterol level in hypercholesterolemic individuals than in normocholesterolemic individuals. These supplements worked by various mechanisms, such as enhancing the excretion of bile acids, inhibiting the absorption of cholesterol in the intestines, increasing the expression of hepatic LDL receptors, suppressing the activity of enzymes involved in cholesterol synthesis, and activating the adenosine monophosphate-activated protein kinase signalling pathway.

Remodeling mechanism of gel network structure of soy protein isolate amyloid fibrils mediated by cellulose nanocrystals

The differences in the gelling properties of soy protein isolate (SPI) and soy protein isolate amyloid fibrils (SAFs) as well as the role of cellulose nanocrystals (CNC) in regulating their gel behaviors were investigated in this study. The binding of CNC to β-conglycinin (7S), glycinin (11S), and SAFs was predominantly driven by non-covalent interactions. CNC addition reduced the particle size, turbidity, subunit segments, and crystallinity of SPI and SAFs, promoted the conversion of α-helix to β-sheet, improved the thermal stability, exposed more tyrosine and tryptophan residues, and enhanced the intermolecular interactions. A more regular and ordered lamellar network structure was formed in the SAFs-CNC composite gel, which could be conducive to the improvement of gel quality. This study would provide theoretical reference for the understanding of the regulatory mechanism of protein amyloid fibrils gelation as well as the high-value utilization of SAFs-CNC complex as a functional protein-based material or food ingredient in food field.

A Review of Bioactive Compound Effects from Primary Legume Protein Sources in Human and Animal Health

The global demand for sustainable and nutritious food sources has catalyzed interest in legumes, known for their rich repertoire of health-promoting compounds. This review delves into the diverse array of bioactive peptides, protein subunits, isoflavones, antinutritional factors, and saponins found in the primary legume protein sources-soybeans, peas, chickpeas, and mung beans. The current state of research on these compounds is critically evaluated, with an emphasis on the potential health benefits, ranging from antioxidant and anticancer properties to the management of chronic diseases such as diabetes and hypertension. The extensively studied soybean is highlighted and the relatively unexplored potential of other legumes is also included, pointing to a significant, underutilized resource for developing health-enhancing foods. The review advocates for future interdisciplinary research to further unravel the mechanisms of action of these bioactive compounds and to explore their synergistic effects. The ultimate goal is to leverage the full spectrum of benefits offered by legumes, not only to advance human health but also to contribute to the sustainability of food systems. By providing a comprehensive overview of the nutraceutical potential of legumes, this manuscript sets a foundation for future investigations aimed at optimizing the use of legumes in the global pursuit of health and nutritional security.

Biofabrication's Contribution to the Evolution of Cultured Meat

Cultured Meat (CM) is a growing field in cellular agriculture, driven by the environmental impact of conventional meat production, which contributes to climate change and occupies ≈70% of arable land. As demand for meat alternatives rises, research in this area expands. CM production relies on tissue engineering techniques, where a limited number of animal cells are cultured in vitro and processed to create meat-like tissue comprising muscle and adipose components. Currently, CM is primarily produced on a small scale in pilot facilities. Producing a large cell mass based on suitable cell sources and bioreactors remains challenging. Advanced manufacturing methods and innovative materials are required to subsequently process this cell mass into CM products on a large scale. Consequently, CM is closely linked with biofabrication, a suite of technologies for precisely arranging cellular aggregates and cell-material composites to construct specific structures, often using robotics. This review provides insights into contemporary biomedical biofabrication technologies, focusing on significant advancements in muscle and adipose tissue biofabrication for CM production. Novel materials for biofabricating CM are also discussed, emphasizing their edibility and incorporation of healthful components. Finally, initial studies on biofabricated CM are examined, addressing current limitations and future challenges for large-scale production.

Soy protein isolate-sodium alginate colloidal particles for improving the stability of high internal phase Pickering emulsions: Effects of mass ratios

The potential of sodium alginate (SA) at different mass ratios to improve the emulsifying ability of soy protein isolate (SPI) in high internal phase Pickering emulsions (HIPPEs) was evaluated in this work. SPI-SA particles were used as a natural particle stabilizer of HIPPEs with 80 % oil phase. The properties of particles with varying SPI to SA ratios (10:0, 10:1, 10:3, 10:5, 10:10, and 10:15 w/w) were evaluated. HIPPEs with a 10:10 SPI to SA ratio exhibited the smallest droplet sizes. Both the storage modulus and loss modulus of the HIPPEs increased with increasing SA addition ratios, implying that HIPPEs with higher SA addition have stronger gel characteristics. In addition, super-resolution microscopy and cryogenic scanning electron microscopy indicated that SA addition strengthened the compactness of the interface film and increased the distribution uniformity of HIPPEs. In conclusion, the combination of SPI and SA is beneficial for improving the performance of HIPPEs.

Research progress on plant-based protein Pickering particles: Stabilization mechanisms, preparation methods, and application prospects in the food industry

At present, there have been many research articles reporting that plant-based protein Pickering particles from different sources are used to stabilize Pickering emulsions, but the reports of corresponding review articles are still far from sufficient. This study focuses on the research hotspots and related progress on plant-based protein Pickering particles in the past five years. First, the article describes the mechanism by which Pickering emulsions are stabilized by different types of plant-based protein Pickering particles. Then, the extraction, preparation, and modification methods of various plant-based protein Pickering particles are highlighted to provide a reference for the development of greener and more efficient plant-based protein Pickering particles. The article also introduces some of the most promising applications of Pickering emulsions stabilized by plant-based protein Pickering particles in the food field. Finally, the paper also discusses the potential applications and challenges of plant-based protein Pickering particles in the food industry.

Protein-Based Rechargeable and Replaceable Antimicrobial and Antifouling Coatings on Hydrophobic Food-Contact Surfaces

The growing concerns regarding foodborne illnesses related to fresh produce accentuate the necessity for innovative material solutions, particularly on surfaces that come into close contact with foods. This study introduces a sustainable, efficient, and removable antimicrobial and antifouling coating ideally suited for hydrophobic food-contact surfaces such as low-density polyethylene (LDPE). Developed through a crosslinking reaction involving tannic acid, gelatin, and soy protein hydrolysate, these coatings exhibit proper stability in aqueous washing solutions and effectively combat bacterial contamination and prevent biofilm formation. The unique surface architecture promotes the formation of halamine structures, enhancing antimicrobial efficacy with a rapid contact killing effect and reducing microbial contamination by up to 5 log10 cfu·cm-2 against both Escherichia coli (Gram-negative) and Listeria innocua (Gram-positive). Notably, the coatings are designed for at least five recharging cycles under mild conditions (pH6, 20 ppm free active chlorine) and can be easily removed with hot water or steam to refresh the depositions. This removal process not only conveniently aligns with existing sanitation protocols in the fresh produce industry but also facilitates the complete eradication of potential developed biofilms, outperforming uncoated LDPE coupons. Overall, these coatings represent sustainable, cost-effective, and practical advancements in food safety and are promising candidates for widespread adoption in food processing environments.

Electron beam irradiation induced aggregation, structural and functional changes of soybean 11S globulin

This study investigated the effects of different irradiation doses of an electron beam (e-beam) (0, 2, 4, 6, 8, and 10 kGy) on the structure, emulsification, foaming, and rheological and gel properties of soybean 11S globulin. The irradiation treatment at 4 and 6 kGy significantly increased the solubility, surface hydrophobicity, disulfide bonding, and ζ-potential of 11S globulin, decreased the particle size of the protein solution, and effectively improved the emulsifying activity and foaming stability of the protein solution. Moreover, irradiation induced moderate cross-linking and aggregation of the proteins, thereby increasing the apparent viscosity and shear stress of the protein solution. In addition, the low-field NMR and microstructure analysis results revealed that protein gels formed a dense and homogeneous three-dimensional mesh structure after irradiation (6 kGy), along with increased content of bound water (T2b) and water not readily flowable (T21) and a decrease content of free water (T22). Overall, our results confirmed that e-beam irradiation could significantly improve the physicochemical properties of soybean 11S globulin. Our study thus provides a new technical means for the application of electron beam irradiation technology toward protein modification and broadens the high-value utilization of soybean 11S globulin in the food processing industry.

Quantitative profiling of supersulfides naturally occurring in dietary meats and beans

Sulfur is essential in the inception of life and crucial for maintaining human health. This mineral is primarily supplied through the intake of proteins and is used for synthesizing various sulfur-containing biomolecules. Recent research has highlighted the biological significance of endogenous supersulfides, which include reactive persulfide species and sulfur catenated residues in thiol and proteins. Ingestion of exogenous sulfur compounds is essential for endogenous supersulfide production. However, the content and composition of supersulfides in foods remain unclear. This study investigated the supersulfide profiles of protein-rich foods, including edible animal meat and beans. Quantification of the supersulfide content revealed that natto, chicken liver, and bean sprouts contained abundant supersulfides. In general, the supersulfide content in beans and their derivatives was higher than that in animal meat. The highest proportion (2.15 %) was detected in natto, a traditional Japanese fermented soybean dish. These results suggest that the abundance of supersulfides, especially in foods like natto and bean sprouts, may contribute to their health-promoting properties. Our findings may have significant biological implications and warrant developing novel dietary intervention for the human health-promoting effects of dietary supersulfides abundantly present in protein-rich foods such as natto and bean sprouts.

A SERS-based immune-nanoprobe for ultrasensitive detection of glycinin via a lateral flow assay

Glycinin is one of the most nutritious ingredients in soybean, but it is also an allergen that can cause allergic reactions in humans and animals, and even endanger life in severe cases. Therefore, it is imperative to develop a rapid and ultrasensitive detection method for glycinin. In order to achieve this goal, this experiment combined surface-enhanced Raman spectroscopy (SERS) technology with an economical, simple, fast and easy-to-carry immunochromatographic test strip, and successfully constructed an efficient sandwich immunochromatographic test strip. The immunoprobe of the test strip was covalently coupled by gold nanostars (AuNSs), Raman molecule 4-aminothiophenol (4-PATP) and rabbit polyclonal antibody. In this experiment, a gold nanostar immunochromatographic test strip for detecting glycinin was established. The detection limit of the test strip was 0.23 ng / mL, the recovery rate was 91.5-96.6 %, and the coefficient of variation was 1.61-6.15 %. In addition, the test strip had no cross reaction with whey protein, wheat protein, peanut protein, sesame protein and β-conglycinin, indicating that the detection method had good specificity and the ability to avoid false positive results. Hence, this experiment successfully prepared a rapid and sensitive test strip for glycinin.

The structure of anthocyanins and the copigmentation by common micromolecular copigments: A review

Under natural physiological conditions, anthocyanins can keep bright and stable color for a long time due to the relatively stable acid-base environment of plant vacuoles and the copigmentation from various copigment substances, such as polyphenols, nucleotides, metallic ions and other substances. Therefore, the copigmentation caused by copigments is considered an effective way to stabilize anthocyanins against adverse environmental conditions. This is attributed to the covalent and noncovalent interactions between colored forms of anthocyanins (flavylium ions and quinoidal bases) and colorless or pale yellow organic molecules (copigments). These interactions are usually manifested in both hyperchromic effect and bathochromic shifts. In addition to making anthocyanins more stable, the copigmentation also could make an important contribution to the diversification of their tone. Based on the molecular structure of anthocyanins, this review focuses on the interaction mode of auxochrome groups or copigments with anthocyanins and their effects on the chemical and color stability of anthocyanins.

Regulation of interfacial mechanics of soy protein via co-extraction with flaxseed protein for efficient fabrication of foams and emulsions

Enrichment of plant proteins with functionality is of great importance for expanding their application in food formulations. This study proposed an innovation to co-enrich soy protein and flaxseed protein to act as efficient interfacial stabilizers for generating foams and emulsions. The structure, interfacial properties, and functionalities of the soy protein-flaxseed protein natural nanoparticles (SFNPs) obtained by alkali extraction-isoelectric precipitation (AE) and salt extraction-dialysis (SE) methods were investigated. Overall, the foamability of AE-SFNPs (194.67 %) was 1.45-fold that of SE-SFNPs, due to their more flexible structure, smaller particle size, and suitable surface wettability, promoting diffusion and adsorption at the air-water interface. AE-SFNPs showed higher emulsion stability (140.89 min), probably because the adsorbed AE-SFNPs with smaller size displayed soft particle-like properties and stronger interfacial flexibility, and therefore could densely and evenly arrange at the interface, facilitating the formation of a stiff and solid-like interfacial layer, beneficial for more stable emulsion formation. The findings may innovatively expand the applications of SFNPs as food ingredients.

Chitin nanocrystals as natural gel modifier for yielding stronger acid-induced soy protein isolate gel

This study aimed to enhance the rheological properties and thermal stability of acid-induced soy protein isolate (SPI) gels by incorporating chitin nanocrystals (ChNCs) and proposing a gelation mechanism. SPI gels exhibited pseudo-plastic behavior. Increasing ChNCs concentration from 0.00 % to 1.00 % improved G' values, recovery rate, and initial degradation temperature: from 75.6 Pa to 1024.3 Pa, 80.27 % to 85.47 %, and 261.5 °C to 275.8 °C, respectively. FTIR analysis confirmed electrostatic and hydrogen bonding interactions between SPI and ChNCs. Adding 1.00 % ChNCs reduced α-helix content from 19.7 % to 12.1 % while increasing β-sheet content from 46.5 % to 52.6 %. This led to protein unfolding, exposure of Trp residues, and orderly aggregation, forming a dense cross-linked gel network. Gel particle size increased from 185.5 nm (no ChNCs) to 504.4 nm (1.00 % ChNCs), with reduced surface charges. Hydrophobic and electrostatic interactions were key forces stabilizing SPI-ChNCs gels. These findings offer a practical approach to enhancing traditional acid-induced protein gel-based functional foods using naturally sourced chitin nanocrystals.

Benefits of Soybean in the Era of Precision Medicine: A Review of Clinical Evidence

Soybean (Glycine max) is an important ingredient of cuisines worldwide. While there is a wealth of evidence that soybean could be a good source of macronutrients and phytochemicals with health-promoting effects, concerns regarding adverse effects have been raised. In this work, we reviewed the current clinical evidence focusing on the benefits and risks of soybean ingredients. In breast, prostate, colorectal, ovarian, and lung cancer, epidemiological studies showed an inverse association between soybean food intake and cancer risks. Soybean intake was inversely correlated with risks of type 2 diabetes mellitus (T2DM), and soy isoflavones ameliorated osteoporosis and hot flashes. Notably, soybean was one of the dietary protein sources that may reduce the risk of breast cancer and T2DM. However, soybean had adverse effects on certain types of drug treatment and caused allergies. In sum, this work provides useful considerations for planning clinical soybean research and selecting dietary protein sources for human health.

Effects of the soy protein to wheat gluten ratio on the physicochemical and structural properties of Alaska pollock surimi-based meat analogs by high moisture extrusion

Surimi products have attracted much attention and are widely used in the food industry. Currently, the processing and exploitation of surimi products are mostly based on their gel characteristics. However, the abundant protein in surimi can be rearranged and integrated by high-temperature melting to generate a new surimi product with fibrous structures. In this study, meat analogs (new surimi product) were produced by high moisture extrusion (HME) using Alaska pollock surimi and plant protein (8:2), where the plant protein consisted of different ratios of soy protein and wheat gluten (9:1, 7:3, 5:5, 3:7 and 1:9). The product was marked as SSG because it was composed of Alaska pollock surimi, soy protein and wheat gluten. The structure and color results showed that the hardness and ΔE of SSG decreased, while the fibrous degree and lightness increased with increasing WG content. The observation of the macrostructure and microstructure also showed that the skeleton structure of SSG was more obvious with increasing WG addition, but the viscosity reflected a decreasing trend. Furthermore, an increase in the WG content raised the free water ratio and the total content of β-sheets, whereas the appropriate plant protein ratio reduced the SSG's thermal stability. In conclusion, Alaskan pollock surimi and the appropriate proportion of plant protein can form structurally stable meat analogs by high moisture extrusion.

The influence of ionic polysaccharides on the physicochemical and techno-functional properties of soy proteins; a comprehensive review

Since the world's population has surged in recent decades, the need for sustainable as well as environmentally friendly protein sources is growing. However, there are daunting challenges in utilizing these protein sources in the food industry due to their poor techno-functional properties compared with animal proteins. Numerous procedures have been introduced to improve plant protein functionalities with related pros and cons. Among them, complexation with polysaccharides is considered a safe and effective process for modulating plant proteins' technological and industrial applications. Notwithstanding the nutritional value of soy protein (SP) as a "complete protein," it is a crucial protein commercially because of its rank as the highest-traded plant-based protein worldwide. The current review deals with SP complexation with ionic polysaccharides, including chitosan, alginate, carrageenan, and xanthan gum, and their effects on the physicochemical and techno-functional properties of SP. Accordingly, the structure of SP and the abovementioned polysaccharides have been considered for a better understanding of the possible interactions. Then, the changes in the physicochemical and functional properties of SP and their potential applications in the formulation of plant-based food products have been discussed. Overall, ionic polysaccharides at optimum conditions would improve the functional properties of SP by altering its secondary structure, making it suitable for a wide range of applications in the food industry.

Evaluation of sono-physico-chemical and processing effects in the mixed sarcoplasmic protein/soy protein isolate system

Since it may be employed to guide the production of high-quality plant protein as a partial substitute for animal protein using sono-physico-chemical effects, it is important to investigate the mixing of animal and plant protein in ultrasound (UID)-assisted processing systems. A study group of sono-physico-chemical processing with five distinct soy protein isolate (SPI)/ sarcoplasmic protein (SPN) ratios was developed in this work. The results showed that adding additional SPN to the mixed protein can increase its sono-physico-chemical impact, and this effect is greatest when the ratio of SPI to SPN is 1:3. The high SPN group's grafting rate rose from 39.13% to 55.26% in comparison to the high SPI content group. Quercetin (Que) may more readily modify SPN than SPI in the "dual protein" system used in this work, highlighting the critical function of plant protein in controlling the effects of UID-assisted processing in the "dual protein" system. Changes in apparent viscosity and microstructure are the primary parameters that affect the severity of sono-physico-chemical effects in SPI/SPN mixed protein systems, in addition to structural variables.

Yellow Field Pea Protein (Pisum sativum L.): Extraction Technologies, Functionalities, and Applications

Yellow field peas (Pisum sativum L.) hold significant value for producers, researchers, and ingredient manufacturers due to their wealthy composition of protein, starch, and micronutrients. The protein quality in peas is influenced by both intrinsic factors like amino acid composition and spatial conformations and extrinsic factors including growth and processing conditions. The existing literature substantiates that the structural modulation and optimization of functional, organoleptic, and nutritional attributes of pea proteins can be obtained through a combination of chemical, physical, and enzymatic approaches, resulting in superior protein ingredients. This review underscores recent methodologies in pea protein extraction aimed at enhancing yield and functionality for diverse food systems and also delineates existing research gaps related to mitigating off-flavor issues in pea proteins. A comprehensive examination of conventional dry and wet methods is provided, in conjunction with environmentally friendly approaches like ultrafiltration and enzyme-assisted techniques. Additionally, the innovative application of hydrodynamic cavitation technology in protein extraction is explored, focusing on its prospective role in flavor amelioration. This overview offers a nuanced understanding of the advancements in pea protein extraction methods, catering to the interests of varied stakeholders in the field.

Effects of Processing Technology on Protein Separation, Quality, and Functional Characteristics

Proteins provide the material foundation of all life activities and play an important role in the physiological and biochemical metabolism of the human body [...].

High moisture extrusion of plant proteins: advances, challenges, and opportunities

High moisture extrusion is a widely used technology for producing fibrous meat analogues in an efficient and scalable manner. Extrusion of soy, wheat gluten, and pea is well-documented and related products are already available in the market. There has been growing interest to diversify the protein sources used for meat analogues due to concerns over food waste, monocropping and allergenicity. Optimizing the extrusion process for plant proteins (e.g., hemp, mung bean, fava bean) tends to be time consuming and relies on the operators' intuition and experience to control the process well. Simulating the extrusion process has been challenging so far due to the diverse inputs and configurations involved during extrusion. This review details the mechanism for fibrous structure formation and provides an overview of the extrusion parameters used for texturizing a broad range of plant protein sources. Referring to these data reduces the resources needed for optimizing the extrusion process for novel proteins and may be useful for future extrusion modeling efforts. The review also highlights potential challenges and opportunities for extruding plant proteins, which may help to accelerate the development and commercialization of related products.

Biomacromolecule assembly of soy glycinin-potato starch complexes: Focus on structure, function, and applications

The effect of the cross-linking mechanism and functional properties of soy glycinin (11S)-potato starch (PS) complexes was investigated in this study. The results showed that the binding effecting and spatial network structure of 11S-PS complexes via heated-induced cross-linking were adjusted by biopolymer ratios. In particular, 11S-PS complexes with the biopolymer ratios of 2:15, had a strongest intermolecular interaction through hydrogen bonds and hydrophobic force. Moreover, 11S-PS complexes at the biopolymer ratios of 2:15 exhibited a finer three-dimensional network structure, which was used as film-forming solution to enhance the barrier performance and mitigate the exposure to the environment. In addition, the 11S-PS complexes coating was effective in moderating the loss of nutrients, thereby extending their storage life in truss tomato preservation experiments. This study provides helpful to insights into the cross-linking mechanism of the 11S-PS complexes and the potential application of food-grade biopolymer composite coatings in food preservation.

MicroRNA-223 Inhibits Soybean Glycinin- and β-Conglycinin-Induced Apoptosis of IPEC-J2 Cells by Targeting NLRP-3 in the IEL/IPEC-J2 Co-culture System

The apoptosis of intestinal porcine epithelial cells induced by soybean antigen protein allergy is one of the most important mechanisms responsible for enteritis. MicroRNAs (miRNAs) affect the cellular and physiological functions of all multicellular organisms. We hypothesize that microRNA-223 inhibits soybean glycinin- and β-conglycinin-induced apoptosis of intestinal porcine enterocytes (IPEC-J2) by targeting the NLR family pyrin domain containing 3 (NLRP-3). Using the intestinal interepithelial lymphocyte (IEL)/IPEC-J2 co-culture system as an in vitro model, we investigate the role of microRNA-223 in the regulation of soybean glycinin- and β-conglycinin-induced apoptosis. In co-cultured IEL/IPEC-J2 cells incubated with glycinin or β-conglycinin, microRNA-223 decreased NLRP-3, ASC, caspase-1, caspase-3, FAS, BCL-2, and APAF-1 expressions in IPEC-J2 cells; decreased cytokine and cyclooxygenase-2 levels; significantly increased cell activity; and inhibited apoptosis. These data supported a novel antiallergic mechanism to mitigate the sensitization of soybean antigenic protein, which involves the upregulation of microRNA-223-targeting NLRP-3.