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Plant‐based meat is projected to address world‐wide meat shortage and supply–demand imbalances, potentially promoting the growth of sustainable diet choices. Soybean is a key ingredient to produce this alternative food, but the off‐flavours that naturally occur in soy can hinder its widespread acceptance among consumers. This review extensively elaborates on the primary compounds responsible for off‐flavours, their formation mechanisms, and removal techniques. Lipoxygenase oxidation–reduction, oleosins removal, adjustment extrusion conditions, and β‐cyclodextrin treatment were discussed. Fermentation mechanisms, solvent extraction, enzymes hydrolysis, flavouring, and controlling storage conditions were summarised. The most crucial, safe, and effective techniques were enzyme restriction, β‐cyclodextrin treatment in conjugation with phospholipase A2, and modification of the extrusion condition. The reviews provide a systematic summary of the development and prevention methods for the undesirable flavour of soy protein isolate and soy‐based meat products. [ABSTRACT FROM AUTHOR]

Summary: To reduce the sodium salt content in protein gel‐based foods, this study investigated the effects of different Na‐K ratios on the gelation properties and structural changes of soy protein isolate (SPI) and potato protein isolate (PPI) composite gels. The results showed that the composite gel properties were further enhanced with increasing Na‐K ratio in the SPI/PPI gel system. Specifically, when the Na‐K ratio was 1:1, the SPI/PPI composite gel exhibited the highest gel strength, gel elasticity, WHC, storage modulus (G′), and β‐sheet content, whereas the α‐helix content and β‐turn content were the lowest. Scanning electron microscopy images revealed a dense and uniform network structure of the composite gel. The addition of low concentrations of Na+ and K+ improved the network structure and water‐holding capacity of the SPI/PPI gel during the heat‐induced gelation process. However, excessively high Na‐K ratios weakened the gel properties. [ABSTRACT FROM AUTHOR]

BACKGROUND: Recent studies have shown that the wettability of protein‐based emulsifiers is critical for emulsion stability. However, few studies have been conducted to investigate the effects of varying epigallocatechin gallate (EGCG) concentrations on the wettability of protein‐based emulsifiers. Additionally, limited studies have examined the effectiveness of soy protein–EGCG covalent complex nanoparticles with improved wettability as emulsifiers for stabilizing high‐oil‐phase (≥ 30%) curcumin emulsions. RESULTS: Soy protein isolate (SPI)–EGCG complex nanoparticles (SPIEn) with improved wettability were fabricated to stabilize high‐oil‐phase curcumin emulsions. The results showed that EGCG forms covalent bonds with SPI, which changes its secondary structure, enhances its surface charge, and improves its wettability. Moreover, SPIEn with 2.0 g L −1 EGCG (SPIEn‐2.0) exhibited a better three‐phase contact angle (56.8 ± 0.3o) and zeta potential (−27 mV) than SPI. SPIEn‐2.0 also facilitated the development of curcumin emulsion gels at an oil volume fraction of 0.5. Specifically, the enhanced network between droplets as a result of the packing effects and SPIEn‐2.0 with inherent antioxidant function was more effective at inhibiting curcumin degradation during long‐term storage and ultraviolet light exposure. CONCLUSION: The results of the present study indicate that SPIEn with 2.0 g L −1 EGCG (SPIEn‐2.0) comprises the optimum conditions for fabricating emulsifiers with improved wettability. Additionally, SPIEn‐0.2 can improve the physicochemical stability of high‐oil‐phase curcumin emulsions, suggesting a novel strategy to design and fabricate high‐oil‐phase emulsion for encapsulating bioactive compounds. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

In this study, the high‐moisture meat analogs (HmMAs) were developed by incorporating defatted sesame cake powder (DSP) in soy protein isolate (SyPI). The quality attributes of HmMA like visual appearance, specific mechanical energy (SME), mass flow rate (MFR), phenolic profile, textural and rheological properties were assessed after varying DSP concentrations (0%, 20%, 40%, and 60% w/w) and feed moisture (FM) levels (55% and 60%). The HmMA1 (derived solely from SyPI) exhibited higher hardness, chewiness, gumminess, cohesiveness, and springiness. The HmMA prepared from SyPI–DSP blends (HmMA2–8) demonstrated significant improvements in nutritional composition, and their visual characteristics indicated noticeable anisotropy. The interaction between SyPI and DSP influenced the quality of HmMA. The higher DSP concentration led to higher MFR and deeper curvatures of U‐shaped structures, whereas lower SMS, textural and rheological properties. The DSP incorporation and 55% FM adjustments allowed mimicking meat cuts with thick fiber, influenced color, and proved advantageous in developing white meat analogs with higher free phenolics. The findings of the study suggest avenues for exploring DSP at a suitable level in SyPI for the development of better quality meat analogs. [ABSTRACT FROM AUTHOR]

BACKGROUND: Food allergies are a growing concern worldwide, with soy proteins being important allergens that are widely used in various food products. This study investigated the potential of transglutaminase (TGase) and lactic acid bacteria (LAB) treatments to modify the allergenicity and structural properties of soy protein isolate (SPI), aiming to develop safer soy‐based food products. RESULTS: Treatment with TGase, LAB or their combination significantly reduced the antibody reactivity of β‐conglycinin and the immunoglobulin E (IgE) binding capacity of soy protein, indicating a decrease in allergenicity. TGase treatment led to the formation of high‐molecular‐weight aggregates, suggesting protein crosslinking, while LAB treatment resulted in partial protein hydrolysis. These structural changes were confirmed by Fourier transform infrared spectroscopy, which showed a decrease in β‐sheet content and an increase in random coil and β‐turn contents. In addition, changes in intrinsic fluorescence and ultraviolet spectroscopy were also observed. The alterations in protein interaction and the reduction in free sulfhydryl groups highlighted the extensive structural modifications induced by these treatments. CONCLUSION: The synergistic application of TGase and LAB treatments effectively reduced the allergenicity of SPI through significant structural modifications. This approach not only diminished antibody reactivity of β‐conglycinin and IgE binding capacity of soy protein but also altered the protein's primary, secondary and tertiary structures, suggesting a comprehensive alteration of SPI's allergenic potential. These findings provide a promising strategy for mitigating food allergy concerns and lay the foundation for future research on food‐processing techniques aimed at allergen reduction. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Summary: The effect of addition of cellulose (insoluble fibre), either with small or large particle size, pectin (soluble fibre), and combined cellulose and pectin (mimic and intact forms) on the textural anisotropy of soy protein isolate (SPI) high‐moisture meat analogue (HMMA) was investigated. Pure soy protein HMMA exhibited a dense and thick protein‐layered structure. Its texture was not affected upon adding cellulose. In contrast, the addition of pectin led to a softer texture that was susceptible to rupture. The HMMA showed improved textural anisotropy and integrity when incorporating the combined cellulose and pectin. Such an effect was more pronounced for the intact fibre form due to its higher water absorption capacity compared to that of the mimic one. Hence, the protein matrix was entrapped with swollen particles, leading to a significant reduction in extrusion pressure and a marked increase in its textural anisotropy. These findings highlight the advantages of combining insoluble and soluble fibres to produce HMMA with improved fibrous texture. [ABSTRACT FROM AUTHOR]

Summary: Feasibility of using konjac glucomannan hydrolysate (KGMH) as prebiotics and wall material for encapsulating probiotics was investigated. Prebiotic activity scores (PASs) were determined for KGMH, inulin, fructooligosaccharides and konjac glucomannan to assess their effectiveness in promoting growth of probiotics and inhibiting enteric mixture. Thermal tolerances of probiotics were also assessed. Lactobacillus rhamnosus L34 and L. acidophilus LA5 exhibited higher PASs and thermal tolerances and were selected for encapsulation; freeze drying and spray drying were used to form and dry encapsulated probiotics. Maltodextrin (MD), soy protein isolate (SPI) and KGMH, either individually or in combination, were comparatively used as wall materials. Freeze drying with SPI and KGMH resulted in highest survival rates for L. rhamnosus L34 (97.92%) and L. acidophilus LA5 (88.94%). In case of spray drying, MD, KGMH and combination of MD and KGMH resulted in drying yields of 55–71%; SPI‐containing formula resulted in lower yields (20–23%). Spray‐dried probiotics exhibited lower survival rates compared to their freeze‐dried counterpart. KGMH, particularly in combination with SPI, emerged as promising material for enhancing probiotics survival during encapsulation. [ABSTRACT FROM AUTHOR]

The overall goal of this research was to develop plant protein-based lipid composite films by examining the effect of shear (mechanical shear; MS vs. high pressure shear; HPS) and type of legume protein isolates (pea, lentil, soy, and faba bean). Compared to MS, HPS emulsions had smaller droplet size, and HPS emulsions from pea and lentil were more viscous than soy and faba bean. The HPS films were lighter and more green and yellow in colour compared to MS films. HPS also improved the mechanical properties of the films resulting in higher tensile and puncture strength for pea and soy and higher tensile elongation and puncture deformation for most of the legumes. There was an inverse relationship between legumes where overall stronger and less flexible films were prepared from pea and soy, and vice versa from lentil and faba bean. HPS resulted in pea and soy films with less swelling ability and higher water vapour permeability (WVP), indicative of a poorer moisture barrier when homogenized this way. The MS films had similar WVP regardless of legume type, while under HPS it was the lowest for faba bean and highest for soy, despite the high swelling ability for both legumes. In short, pea, lentil, and faba bean protein isolates prepared emulsion films with good mechanical properties and water resistance, suggesting the potential to replace soy as edible packaging materials. HSP films had better mechanical attributes but poorer vapor barrier properties then those produced using MS. [ABSTRACT FROM AUTHOR]

Incorporating plant protein isolates into milk can enhance probiotic culture growth by providing essential nutrients and altering the physicochemical properties of fermented milk. This study investigated the effects of adding 1.5% or 3.0% soy, pea, and whey protein isolates on the growth of Lacticaseibacillus casei and Lactobacillus johnsonii monocultures, as well as the physicochemical (acidity, syneresis, color) and organoleptic properties of fermented milk during 21 days of refrigerated storage. The results showed that 1.5% SPI and WPI did not significantly alter milk acidity compared to controls. Still, pH increased with 1.5% and 3.0% PPI. Storage time significantly affected pH in L. casei fermented milk. The initial addition of WPI at 1.5% and 3.0% reduced syneresis in L. casei fermented milk compared to other samples. Color components were significantly influenced by isolates. Initial L. casei cell counts were lower with SPI (LCS1.5 and LCS3) and 1.5% PPI (LCP1.5) compared to controls. Increasing isolate concentration from 1.5% to 3% enhanced L. johnsonii growth in WPI-milk but reduced L. casei in LCW3 compared to LCW1.5. Only increased pea protein concentration significantly increased L. casei growth. Probiotic populations generally were reduced during extended storage. Moreover, isolates impacted milk organoleptic evaluation. This research demonstrates the potential of protein isolates in creating health-promoting and diverse fermented products and offers insights into their interaction with probiotic cultures to advance functional food technologies. [ABSTRACT FROM AUTHOR]

Soy protein isolated (SPI) have a wide application in the food packaging, but their water resistance, mechanical properties and antibacterial properties are not ideal for directly use. In our study, we developed a series of SPI composite films loaded with cinnamaldehyde and titanium dioxide (TiO2). X‐ray diffraction (XRD), UV scanning spectra (UV) and spectro colorimeter were applied to indicate the structure of films. The incorporation of TiO2 (0.5%) caused a subsequent effect on the tensile property, UV blocking properties and water vapor properties (WVP). On the other hand, SPI film composed with a constant amount of TiO2 and different concentration of cinnamaldehyde showed an excellent synergistic effect to improve the tensile property, moisture content, UV blocking properties, water vapor properties and morphological characteristics. Furthermore, the composite films exhibited superior antibacterial activity when tested against both S. aureus and E. coli. The microstructure of the composite film become heterogeneous and rough after addition of TiO2 and cinnamaldehyde compare to control film. The findings of the present study may facilitate a re‐evaluation of the potential of using multiple compounds to prepare active edible films. [ABSTRACT FROM AUTHOR]

The gel properties and molecular conformation of Spanish mackerel myofibrillar protein (MP) induced by soy protein isolate–inulin conjugates (SPI–inulin conjugates) were investigated. The addition of SPI–inulin conjugates significantly enhanced the quality of the protein gel. An analysis of different additives was conducted to assess their impact on the gel strength, texture, water-holding capacity (WHC), water distribution, intermolecular force, dynamic rheology, Raman spectrum, fluorescence spectrum, and microstructure of MP. The results demonstrated a substantial improvement in the strength and water retention of the MP gel with the addition of the conjugate. Compared with the control group (MP), the gel strength increased from 35.18 g·cm to 41.90 g·cm, and WHC increased from 36.80% to 52.67% with the inclusion of SPI–inulin conjugates. The hydrogen bond content was notably higher than that of other groups, and hydrophobic interaction increased from 29.30% to 36.85% with the addition of SPI–inulin conjugates. Furthermore, the addition of the conjugate altered the secondary structure of the myofibrillar gel, with a decrease in α-helix content from 62.91% to 48.42% and an increase in β-sheet content from 13.40% to 24.65%. Additionally, the SPI–inulin conjugates led to a significant reduction in the endogenous fluorescence intensity of MP. Atomic force microscopy (AFM) results revealed a substantial increase in the Rq value from 8.21 nm to 20.21 nm. Adding SPI and inulin in the form of conjugates is an effective method to improve the gel properties of proteins, which provides important guidance for the study of adding conjugates to surimi products. It has potential application prospects in commercial surimi products. [ABSTRACT FROM AUTHOR]

BACKGROUND RESULTS CONCLUSION Encapsulation of bioactive compounds within protein‐based nanoparticles has garnered considerable attention in the food and pharmaceutical industries because of its potential to enhance stability and delivery. Soy protein isolate (SPI) has emerged as a promising candidate, prompting the present study aiming to modify its properties through controlled thermal and trypsin treatments for improved encapsulation efficiency (EE) of lutein and its storage stability.The EE of lutein nanoparticles encapsulated using SPI trypsin hydrolysates (SPIT) with three varying degrees of hydrolysis (4.11%, 6.91% and 10.61% for SPIT1, SPIT2 and SPIT3, respectively) increased by 12.00%, 15.78% and 18.59%, respectively, compared to SPI. Additionally, the photostability of SPIT2 showed a remarkable increase of 38.21% compared to SPI. The superior encapsulation efficiency and photostability of SPIT2 was attributed to increased exposure of hydrophobic groups, excellent antioxidant activity and uniform particle stability, despite exhibiting lower binding affinity to lutein compared to SPI. Furthermore, in SPIT2, the protein structure unfolded, with minimal impact on overall secondary structure upon lutein addition.The precise application of controlled thermal and trypsin treatments to SPI has been shown to effectively produce protein nanoparticles with substantially improved encapsulation efficiency for lutein and enhanced storage stability of the encapsulated lutein. These findings underscore the potential of controlled thermal and trypsin treatments to modify protein properties effectively and offer significant opportunities for expanding the applications of protein‐based formulations across diverse fields. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Background Results Conclusions Gluten‐free bread (GFB) has technical bottlenecks such as hard texture, rough taste and low nutrition in practical production. In order to solve these problems, this study used germinated brown rice starch as the main raw material, and investigated the effects of soybean isolate protein (SPI) on the multiscale structure of germinated brown rice starch and bread quality.A gluten‐free rice bread process simulation system was established, and the interaction between SPI and starch in the simulation system was characterized. The result shows that the interaction forces between SPI and germinated brown rice starch were mainly represented by hydrogen bonds, and with the addition of SPI, the crystallinity of starch showed a downward trend. At the same time, when the amount of SPI was 3%, the appearance quality was the best and the specific volume of bread was 1.08 mL g−1. When the amount of SPI was 6%, the texture quality was the best. Compared with the bread without SPI, the hardness of the bread with 6% SPI was reduced by 0.13 times, the springiness was increased by 0.03 times, the color was the most vibrant, the L* value being 1.02 times the original, and the baking loss was reduced to 0.98 times the original.The interaction force between SPI and germinated brown rice starch and its effect on bread quality were clarified, and these results inform choices about providing a theoretical basis for the subsequent development of higher‐quality GFB. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

The effects of different concentrations of soy protein isolate (SPI) on the functional, rheological, pasting, and structural properties of potato starch (PS) are investigated. The water and oil absorption capacity (OAC) of PS‐SPI mix increased significantly with the addition of SPI. Gel strength, peak, final, breakdown, and setback viscosity of PS decreases, whereas the pasting temperature increases with an increase in SPI fraction. Both the Herschel–Bulkley and power law model are found to equally fit in steady state rheology. The PS‐SPI blend exhibits pseudoplastic behavior. The addition of SPI decreases the storage (G′) and loss modulus (G″). SPI also lowers the flow stress values in the amplitude sweep test. Frequency sweep confirms the formation of weak gel formation in PS‐SPI blend by exhibiting a lower value of G′ and G″ than the pure starch. The microstructure of composite gel appears less dense with greater pore size than starch gel. The hardness of the SPI‐PS blend gel decreases from 6.76 to 0.85 N when the SPI content is increased from 0% to 50%. Fourier transform infrared (FTIR) confirms that no chemical groups are formed or destroyed during the composite gel‐making process. [ABSTRACT FROM AUTHOR]

The purpose of this research is to encapsulate the phenolic compounds of rhubarb stem's juice with chitosan and soy protein isolate and checking their effects on the properties of pomegranate juice. For this purpose, the phenolic compounds of rhubarb stem's juice were extracted by methanol and encapsulated with chitosan and soy protein isolate by nanoemulsion method, and finally the resulting microcapsules and nanocapsules were used to enrich pomegranate juice samples. The highest percentage of encapsulation efficiency of phenolic compounds was with soy protein isolate (45.26%). The results of SEM images showed that the particles were relatively spherical and with a relatively smooth surface, also chitosan nanocapsules with an average size of 281.4 nm and soy protein isolate microcapsules with an average size of 22.33 µm were formed. The results of pH analysis showed that the samples enriched with chitosan nanocapsules and soy protein isolate microcapsules showed more and less pH decrease than the control samples during the storage period. The results of DPPH radical scavenging activity showed that the enrichment of pomegranate juice with chitosan nanocapsules increased the antioxidant activity of the samples for up to 3 months of storage. [ABSTRACT FROM AUTHOR]

Proteins are widely consumed for their nutritional benefits, and they possess many applications such as emulsifiers, foaming agents, fat replacers, and thickeners which aid in obtaining the desired rheology and texture of food products. Moreover, the formation of protein–carbohydrate complex can further enhance the functional properties. Hence, the present study investigated the effect of ultrasonic cavitation in the formation of soy protein-rice starch complexes. Ultrasound treatment at 60% amplitude (450 W) combined with heat treatment formed complexes with enhanced solubility, water holding, and foaming properties compared to raw soy protein isolates. Further, sonication preserved the crystalline nature of the complexes formed. The molecular docking studies performed using 11 S protein (1FXZ) indicate the formation of the hydrogen bonds of shorter distances between glutamine (GLN) and leucine (LEU) amino acids with the OH group of rice starch. The complexes formed had excellent functional properties, which increased their scope of application in the food industry. [ABSTRACT FROM AUTHOR]

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In this study, an active biofilm was developed by incorporating red dragon fruit peel (RDF) extract into soy protein isolate (SPI) film matrix for sustainable food packaging. The addition of betalain-rich-RDF extract (1–7 wt%) significantly improved UV-blocking and antioxidant properties of the film compared to the control film. As wt% of RDF-extract increased, water vapor permeability, water solubility, and elongation at break decreased by 1.06 × 10–10 g m m−2 s−1 Pa−1, 34.25%, and 133.25%, respectively. On the other hand, Tensile strength increased significantly (P < 0.05) by 78.76%. FTIR results confirmed the intermolecular interaction between RDF extract and SPI through hydrogen bonding, while XRD result showed a decrease in the crystallinity degree of the film with RDF extract addition. However, no significant change in the TGA curve between extract-incorporated SPI films was observed. SEM analysis revealed that SPI B and SPI D films had a more compact and denser structure than the control film, while AFM analysis showed an increase in Ra and Rq values representing higher surface roughness of SPI D film. SPI D film also significantly (P < 0.05) decreased the weight loss and increased total soluble solids of freshly cut apples over 7-day storage period. [ABSTRACT FROM AUTHOR]

Curcumin (CUR) is found to exhibit a broad spectrum of potentially beneficial biological activities, which make it suitable as a nutraceutical ingredient in functional foods and supplements. But its application for this purpose is often limited by its low water-solubility, chemical stability, and bioavailability. In this study, acid-treated soybean protein isolate (SPI) and chitosan quaternary ammonium salt (CQAS) were used to assemble colloidal carriers for CUR to form soybean protein isolate-curcumin-chitosan quaternary ammonium salt nanoparticles (SPI-CUR-CQAS NPs). The nanoparticles formed were relatively small (< 400 nm), approximately spherical, and strongly positively charged (> 45 mV). Fluorescence spectroscopy demonstrated that the dominant interaction between CUR and SPI was hydrophobic attraction, while the dominant interaction between CQAS and SPI was electrostatic attraction. The encapsulation efficiency (95.4%) and loading capacity (14%) of the SPI-CUR-CQAS NPs (pH 1.5) were relatively high. The vitro digestion experiments showed that the CUR was progressively released from the nanoparticles under stomach, small intestine, and colon conditions. Moreover, the final bioavailability of the encapsulated CUR (63%) was much higher than for free CUR (18.5%). The SPI-CQAS NPs developed in this study can therefore be used as an effective delivery system for CUR in functional foods. [ABSTRACT FROM AUTHOR]

As a protein extracted from soybeans, soy protein isolate (SPI) may undergo the Maillard reaction (MR) with co-existing saccharides during the processing of soy-containing foods, potentially altering its structural and functional properties. This work aimed to investigate the effect of mono- and polysaccharides on the structure and functional properties of SPI during MR. The study found that compared to oat β-glucan, the reaction rate between SPI and D-galactose was faster, leading to a higher degree of glycosylation in the SPI–galactose conjugate. D-galactose and oat β-glucan showed different influences on the secondary structure of SPI and the microenvironment of its hydrophobic amino acids. These structural variations subsequently impact a variety of the properties of the SPI conjugates. The SPI–galactose conjugate exhibited superior solubility, surface hydrophobicity, and viscosity. Meanwhile, the SPI–galactose conjugate possessed better emulsifying stability, capability to produce foam, and stability of foam than the SPI–β-glucan conjugate. Interestingly, the SPI–β-glucan conjugate, despite its lower viscosity, showed stronger hypoglycemic activity, potentially due to the inherent activity of oat β-glucan. The SPI–galactose conjugate exhibited superior antioxidant properties due to its higher content of hydroxyl groups on its molecules. These results showed that the type of saccharides had significant influences on the SPI during MR. [ABSTRACT FROM AUTHOR]

Tofu quality is determined by a controlled coagulation process using a W/O/W emulsion coagulant. The impact of adding soy protein isolate (SPI) to the inner water phase on the stability of W/O/W high-internal-phase emulsions (HIPEs) and its application as a coagulant for tofu was assessed. No creaming occurred during 7-day storage with SPI concentrations up to 0.3%, while the emulsion droplets aggregated with 0.5% and 0.7% SPI. Emulsions containing 0.3% SPI maintained a constant mean droplet size after 21 days of storage and exhibited the lowest TURBISCAN stability index value. HIPE stability against freeze–thaw cycles improved after heating. HIPEs with SPI concentrations above 0.3% demonstrated an elastic gel-like behavior. The increased viscosity and aggregation of the protein around droplets indicated that the interaction among emulsion droplets could enhance stability. W/O/W HIPE coagulants significantly increased tofu yield, reduced hardness, and produced a more homogenous tofu gel compared to a MgCl2 solution. The HIPE with 0.3% SPI was found to be optimal for use as a coagulant for tofu. [ABSTRACT FROM AUTHOR]

Plant-based meat is growing globally due to health, environmental, and animal welfare concerns, though there is a need for quality improvements. This study assessed how different ratios of wheat gluten (WG) to soy protein isolate (SPI) and various baking methods—hot air (HA), microwave (MW), and a combination of both (HA–MW)—affect the physicochemical properties of plant-based meat. Increasing the SPI from 0% to 40% significantly enhanced lightness, hardness, chewiness, water-holding capacity, moisture content, and lysine (an essential amino acid) (p ≤ 0.05). Hardness and chewiness ranged from 4.23 ± 1.19 N to 25.90 ± 2.90 N and 3.44 ± 0.94 N to 18.71 ± 1.85 N, respectively. Baking methods did not affect amino acid profiles. Compared to HA baking, MW and HA–MW baking increased lysine content (561.58–1132.50 mg/100 g and 544.85–1088.50 mg/100 g, respectively) while reducing fat and carbohydrates. These findings suggest that a 40% SPI and 60% WG ratio with microwave baking (360 W for 1 min) optimizes plant-based meat, offering benefits to both consumers and the food industry in terms of health and sustainability. [ABSTRACT FROM AUTHOR]

The structures and properties of the composite films formed by soy protein isolate (SPI) and xanthan gum (XG) with different other matrices were investigated. The composite films were prepared with SPI and XG by adding sodium alginate (SA), carboxymethyl cellulose (CMC), gelatin (GEL), pectin (PEC) and agar (Agar), respectively. The thickness, mechanical properties, oxygen permeability and opacity of the composite films were measured, and their structures were characterized. The results showed that the thicknesses of composite films with 1.5 g of different other matrices were significantly higher (P

Soybean protein has high nutritional value, but its functional properties are easily affected by external factors, which limits its application in food industry. In the study, soybean protein isolate (SPI) was modified by dry heat glycation of galactooligosaccharides (GOS). The gel properties, antioxidant properties and structural changes of SPI-GOS conjugates were investigated. The application of SPI-GOS conjugates in noodles was also explored. The results observed that the glycation degree of SPI increased with the increasing reaction time. SDS-PAGE and spectral analysis showed the changes of spatial conformation of SPI after glycation. The antioxidant activity of SPI increased after glycation and DPPH radical scavenging activity of SPI-GOS peaked at 48 h of reaction. The hardness, elasticity and resilience of soybean protein gel reached their relative maximum at 48 h, 48 h and 12 h of glycation reaction, respectively. Moreover, the appropriate addition of glycated SPI improved the quality of noodles. The noodles with 4% addition of SPI-GOS had higher hardness, elasticity and tensile properties. This study will provide an effective method to modify soybean protein and expand the use of soybean protein in food industry.

To develop low-salt meat products and achieve the reduction in costs of meat production, the effect of konjac gum on the gel properties of soy protein isolate (SPI)-myofibrillar protein (MP) composite at various salt concentrations was investigated in this study. For the purpose of evaluating the effects of SPI, konjac gum, salt concentration, and other factors on MP gel formation, rheological properties and microstructures of the SPI-MP composite gels were analyzed using a rheometer and scanning electron microscopy. The obtained results indicated that at low salt concentration (0.3 mol/L NaCl), the gel strength of 3% MP-1% SPI composite gel significantly increased (P

In this study, the effects of four Hofmeister salts (KCl, NaCl, CaCl2 and MgCl2) at different concentrations (0.02, 0.04 and 0.06 mol/L) on gel properties and rheological properties of soy protein isolate (SPI) were systematically explored. The results showed that the addition of salt ions could improve the gel strength of SPI, but higher concentrations (0.04 and 0.06 mol/L) of CaCl2 and MgCl2 reduced the gel stickiness of the samples. In the dynamic rheological test, each salt ion increased the storage modulus (G’) and loss modulus (G”) of the samples to varying degrees. Higher concentrations of CaCl2 and MgCl2 caused excessive aggregation of SPI, whereas lower concentrations of CaCl2 and MgCl2 exerted an opposite effect. In the temperature sweep test, CaCl2 and MgCl2 changed the trend of G’ and G”, while KCl and NaCl simply increased G’ and G” without changing their trend. In the steady rheological test, higher concentrations of CaCl2 and MgCl2 reduced the apparent viscosity and shear force of the samples, while an opposite effect was observed under the other salt conditions. The decreasing order of the effects of higher concentrations of salt ions on the apparent viscosity and shear force was K+ > Na+ > Mg2+ > Ca2+. In summary, at specific salt ion concentrations (0.04 and 0.06 mol/L), the changes in gel and rheological properties of SPI were consistent with the Hofmeister effect.

To develop low-salt meat products and achieve the reduction in costs of meat production, the effect of konjac gum on the gel properties of soy protein isolate (SPI)-myofibrillar protein (MP) composite at various salt concentrations was investigated in this study. For the purpose of evaluating the effects of SPI, konjac gum, salt concentration, and other factors on MP gel formation, rheological properties and microstructures of the SPI-MP composite gels were analyzed using a rheometer and scanning electron microscopy. The obtained results indicated that at low salt concentration (0.3 mol/L NaCl), the gel strength of 3% MP-1% SPI composite gel significantly increased (P<0.05) to 97 g relative to 43 g of the 4% MP gel, and the water-holding capacity also increased from 36% to 50%. However, the gel strength and water-holding capacity were decreased when the replacement amount of SPI increased (2% MP-2% SPI composite) compared with 3% MP-1% SPI composite. The gel strength decreased from 177 g of 4% MP to 89 g of 2% MP-2% SPI composite with at 0.6 mol/L NaCl concentration. The gel strength and water holding capacity of the MP-SPI composite gel were increased after adding high amount of konjac gum. At 0.3 mol/L NaCl concentration, the gel strength of 2% MP-2% SPI composite increased from 66 g to 93 g after adding 1% konjac gum, and the water holding capacity also increased from 44% to 65%. Therefore, konjac gum can eliminate the disruption of SPI on the gel formation of MP. The results of scanning electron microscopy revealed that the strong water-holding capacity of konjac gum and the filling effect of SPI led to the increase in gel strength. Consequently, at the concentration of 0.3 mol/L salt, 0.5%~1% konjac gum could improve the characteristics of MP protein gel with low SPI substitution (1%). [ABSTRACT FROM AUTHOR]

BACKGROUND: In the quest for sustainable food ingredients, the present study delves into the potential of a tri‐component hydrocolloid blend, comprising gellan gum (GG), soy protein isolate (SPI) and maltodextrin (MD), as a replacement for egg white in meringue production. The research aims to elucidate the intricate physical properties of meringue containing this tri‐component structure, focusing on foaming dynamics, rheological behavior and the textural properties of the resulting meringue cookies. RESULTS: Experiments were conducted with various hydrocolloids (k‐carrageenan, GG, and locust bean gum) and GG was identified as optimal for improving foaming capacity and foaming stability. Rheological evaluations showed a positive correlation between increased GG concentration within the tri‐component matrix and an increase in both storage modulus (G') and loss modulus (G"), indicating improved structural integrity. Furthermore, a comparative analysis of the texture profiles of cookies prepared with this blend highlighted the ability of higher GG concentrations to satisfactorily replicate the tactile and visual qualities of traditional egg white‐based meringues. This result was particularly evident compared to formulations utilizing solely SPI or the combined SPI–MD configuration. CONCLUSION: Conclusively, the results of the present study highlight the significant potential of the GG‐SPI‐MD tri‐component structure to closely mimic the critical properties of egg white, thus offering a promising plant‐based alternative for meringue production. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Soybean protein isolate (SPI) is a highly functional protein source used in various food applications, such as emulsion, gelatin, and food packaging. However, its commercial application may be limited due to its poor mechanical properties, barrier properties, and high water sensitivity. Studies have shown that modifying SPI through glycosylation can enhance its functional properties and biological activities, resulting in better application performance. This paper reviews the recent studies on glycosylation modification of SPI, including its quantification method, structural improvements, and enhancement of its functional properties, such as solubility, gelation, emulsifying, and foaming. The review also discusses how glycosylation affects the bioactivity of SPI, such as its antioxidant and antibacterial activity. This review aims to provide a reference for further research on glycosylation modification and lay a foundation for applying SPI in various fields. [ABSTRACT FROM AUTHOR]

The soy protein isolate cheese sticks were developed in order to enrich the cheese stick products, and the tastes were compared with that of homemade traditional cheese sticks. Single factor experiments and Box - Behnken four-factor and three-level experiment design were used to explore the effects of skimmed milk powder and soy protein isolate additions, skimmed milk powder to soy protein isolate mass ratios, complex emulsifying salt additions and compound stabilizer additions on the qualities and tastes of soy protein isolate cheese sticks. The formulation of soy protein isolate cheese sticks was optimized, and its taste was analyzed. The results showed that the optimal formula of soy protein isolate cheese sticks was determined as follow: on the basis of 100 g water, total addition of skimmed milk powder and soy protein isolate of 16.0%, compound emulsified salt addition of 2.0%, compound stabilizer addition of 3.0%, and skimmed milk powder to soy protein isolate mass ratio of 3:1. Compared with the traditional cheese sticks, soy protein isolate cheese sticks presented higher protein content, lower carbohydrate content with richer tastes. According to the optimal formula, the prepared soy protein isolate cheese sticks exhibited uniform structure, good color, moderate softness and hardness with rich milk and bean flavors, which provided technical supports for the marketization of the products. [ABSTRACT FROM AUTHOR]

This study mainly investigated the effect of soy protein isolate (SPI) on the gel quality of silver carp surimi under different storage conditions (storage temperatures of 4 °C, −20 °C, and −40 °C, and storage times of 0, 15, and 30 d). The results found that 10% SPI could inhibit the growth of ice crystals, improve the water distribution, enhance the water holding capacity of the gels, and strengthen the interaction between surimi and proteins. Compared to the control group, the composite silver carp surimi gel exhibited superior quality in texture, chemical interactions, and rheological properties during cold storage. Fourier transform infrared spectroscopy revealed an increasing trend in α-helix and β-turn content and a decreasing trend of β-sheet and random coil content. As storage time increased, the gel deterioration during cold storage inhibitory effect of the treatment group was superior to the control group, with the best results observed at −40 °C storage conditions. Overall, SPI was a good choice for maintaining the quality of silver carp surimi gel during cold storage, which could significantly reduce the changes in the textural properties during cold storage with improved water holding capacity. [ABSTRACT FROM AUTHOR]

Owing to the increasing low-carbon demand, environmentally friendly supercapacitors with low temperature resistance have attracted increasing attention. Herein, biomass hydrogels were successfully fabricated by covalently cross-linked lignin (Lig) with soy protein isolate (SPI) and assembled into supercapacitors. The performance of hydrogel electrolytes and the electrochemical performance of supercapacitors were studied systematically. The hydrogel electrolyte achieved the highest ionic conductivity of 0.086 S cm−1 with 50% addition of SPI. The supercapacitor displayed an excellent specific capacitance of 150.80 F g−1 at room temperature. Importantly, over 10,000 charge-discharge cycles, the capacitance retention rate maintained more than 73.5%, and the coulombic efficiency was around 100%. Besides, the electrochemical performance of the supercapacitors at low temperature was investigated as well. Even at −20 °C, the flexible supercapacitor could keep a specific capacitance of 135.71 F g−1, with a capacitance retention rate up to 90% of room temperature, indicating a prominent resistance at subzero temperature. Overall, this work lays a foundation for the preparation of environmentally friendly and low temperature resistant solid-state supercapacitors, which is conducive to the practical application under harsh environments. [ABSTRACT FROM AUTHOR]

Summary: Phytoproteins have been widely implemented in the food industry benefiting from their good functionalities, vast reserves and relatively low cost. However, phytoproteins frequently experience poor solubility, which limits their applications. In our study, the solubility of soy protein isolate (SPI) treated with pH‐shifting increased over 1.8 times; however, the transglutaminase‐induced gel properties were sacrificed. To solve this problem, walnut protein (WP) was used to co‐assemble with SPI during the treatment. The co‐assembly hybrid protein shows significantly better solubility, meanwhile, maintaining the transglutaminase‐induced gel properties and improving the cohesiveness and resilience properties compared with untreated SPI, which behaved an improved water holding capacity during storage. The detailed mechanisms were investigated with rheological analysis, SEM, textural analysis and Fourier transform infrared spectroscopy (FTIR). Overall, our study provided a promising strategy to develop SPI/WP hybrid composites with high solubility and improved gel properties to extend the application of SPI in the food industry. [ABSTRACT FROM AUTHOR]

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In the present study, at the first a blending of sodium alginate and soy protein isolate (SPI) as wall material were used to encapsulate chia seed (Salvia hispanica) oil as a source of omega-3 into the microspheres. The microspheres were formed at different ratios (5:1, 5:3, and 5:5) of sodium alginate/ (SPI) via the extrusion method, maintaining a constant core/wall ratio of 10%. Morphological structures and physicochemical properties of the microspheres were investigated. In the second step, the microspheres with a ratio 5:3 of alginate/SPI were added to dark chocolate formulation. The characteristics of the fortified dark chocolate were compared to the control sample through sensory evaluation, moisture content and water activity, differential scanning calorimetric (DSC), and texture analysis. The sensory evaluation revealed that the fortified dark chocolate achieved higher acceptance levels compared to the control sample, indicating its potential for commercial success. This research demonstrates a promising approach to enhance the nutritional profile of chocolate while maintaining its sensory appeal. Practical applications: • A blend of SPI/Alginate was successfully used to well entrap the chia seed oil. • Fortified dark chocolate with alginate/SPI microspheres showed higher acceptance level. • Alginate/SPI microspheres show a potential for enhancing nutritional profile of foods. [ABSTRACT FROM AUTHOR]

The present study aimed to investigate the properties of calcium-rich soy protein isolate (SPI) gels (14% SPI; 100 mM CaCl2), the effects of incorporating different concentrations locust bean gum (LBG) (0.1–0.3%, w/v) to the systems and the stability of the obtained gels. Also, the incorporation of solid lipid microparticles (SLMs) was tested as an alternative strategy to improve the system's stability and, therefore, potential to be applied as a product prototype. The gels were evaluated regarding their visual aspect, rheological properties, water-holding capacities (WHCs) and microstructural organizations. The CaCl2-induced gels were self-supported but presented low WHC (40.0% ± 2.2) which was improved by LBG incorporation. The obtained mixed system, however, presented low stability, with high syneresis after 10 days of storage, due to microstructural compaction. The gels' stability was improved by SLM incorporation, which decreased the gelled matrices' compaction and syneresis for more than 20 days. Even though the rheological properties of the emulsion-filled gels (EFGs) were very altered due to the ageing process (which may affect the sensory perception of a future food originated from this EFG), the incorporation of SLMs increased the systems potential to be applied as a calcium-rich product prototype. [ABSTRACT FROM AUTHOR]

In this study, soy protein isolate (SPI) films incorporating quercetin-grafted dialdehyde starch (DAS-QR) and DAS/QR, respectively, were developed. The structural, physical, and functional properties of the composite films were determined. The results suggested that DAS-QR and DAS/QR formed hydrogen bonding with the SPI matrix, which improved the structural properties of the films. The light-blocking capacity, thermal stability, hydrophobicity, tensile strength, elongation at break, and antioxidant and antibacterial abilities of SPI films were improved by DAS-QR and DAS/QR. Notably, SPI films incorporated with DAS-QR exhibited better performance than those with DAS/QR in terms of antioxidant (SPI/DAS-QR: 79.8% of DPPH and 62.1% of ABTS scavenging activity; SPI/DAS/QR: 71.4% of DPPH and 56.0% of ABTS scavenging activity) and antibacterial abilities against S. aureus (inhibition rate: 92.7% for SPI/DAS-QR, 83.4% for SPI/DAS/QR). The composite coating film SPI/DAS-QR effectively maintained appearance quality, delayed the loss of weight and total soluble solids, postponed malondialdehyde accumulation, and decreased peroxidase activity and microbial contamination in fresh-cut potatoes. These good performances highlight SPI/DAS-QR as a promising active packaging material for fresh-cut product preservation. [ABSTRACT FROM AUTHOR]

Soy protein isolate (SPI) and its mixture with other biopolymers, such as linear polysaccharides, have been considered as potential components to form biodegradable packaging. Films based on SPI (5% m/m film-forming solution) were prepared with the addition of sodium alginate (ALG) at different concentrations and pH values. The mechanical properties and oxygen permeability were studied and correlated with the crystallinity (X-ray), Fourier transform infrared (FT-IR) spectroscopy and the microstructure (scanning electron microscopy - SEM) of the films. The addition of ALG caused expressive changes in the structural arrangement of the SPI films, especially at pH 6 and 8. The FT-IR spectra of the films also showed the effects of the pH and ALG concentration on the relative intensity of the protein absorption bands, indicating stronger interaction between SPI and ALG at pH 11 than at pH 6 and 8. The resistance of the films was improved with the increasing addition of the polysaccharide, and with the highest alkalinity. Oxygen permeability evaluation of the films formed at pH 11 showed a significant decrease in permeability with increasing incorporation of ALG into the film matrix. The results indicate that the structure and the properties of the SPI-based films were modified and improved with ALG. It was concluded that alginate incorporation in SPI-based films with pH 11 improves mechanical and oxygen barrier properties. [ABSTRACT FROM AUTHOR]

As the world attempts to decarbonise the food industry and limit greenhouse gas (GHG) emissions, plant-based meat analogues (PBMAs) have emerged as a sustainable alternative to traditional meat. The objective of this study is to assess the environmental impacts of PBMAs compared to traditional beef burgers, aiming to address the research gap in the life cycle assessments (LCAs) of publicly available PBMA recipes. Utilising a cradle-to-fork system boundary, this research conducted a rigorous LCA on a 100 g plant-based burger patty and its beef burger (BB) counterpart, each produced in the UK but sourced from different global locations. The results demonstrated that the plant-based burger had significantly lower environmental impacts across several categories, including a 65% reduction in global warming potential and a 45% reduction in water consumption. A simple extrapolation illustrated that if the UK population switched from beef to meat analogue patties, 3 million tonnes of CO2e could be saved annually, corresponding to 0.74% of the country's yearly territorial GHG emissions. Scenario analyses displayed how the environmental impact of the MA patty remained stable regardless of changes in exportation, ingredient origin or soy protein sourcing. Moreover, a sensitivity analysis conducted with an alternative characterisation method corroborated the initial findings, whilst uncertainty analysis ensured that nearly all of the conclusions generated from the original comparison were robust. Future studies should conduct LCAs on PBMA patties with commercial recipes using varied plant-based sources, as well as fully understanding any potential health implications of long-term PBMA consumption. [ABSTRACT FROM AUTHOR]

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.

pH, NaCl and temperature are important process parameters for the manufacturing of soybean protein isolate (SPI). pH and NaCl affect protein aggregation by modifying the surface charge and electrostatic repulsion, whereas temperature affects protein aggregation by changing the surface hydrophobicity and/or disulfide bonding, which in turn changes the particle size and compactness and then the rheology and downstream application characteristics of SPI. This paper reviews the effects and possible mechanisms of pH, NaCl, and temperature on the denaturation, aggregation, and rheological properties of SPI and its components glycinin and β-conglycinin with respect to interaction, thermal stability, degree of aggregation, and gelling properties. The relationship between the degree of protein aggregation, gel strand thickness, gel strand curvature and gel network continuity and gel strength is discussed, and the differences among the effects of pH, NaCl and temperature on protein aggregation are summarized for the purpose of providing an assistance in regulating the degree of SPI aggregation by preparation parameters.

In this study, to understand the effect of hydrodynamic cavitation (HC) treatment on the interaction between catechin and soy protein isolate (SPI) and the structural and functional properties of the conjugates, we explored the changes in binding between catechin and SPI as well as the ultraviolet (UV) absorption and fluorescence spectra, free sulfhydryl and amino group contents, surface hydrophobicity, average particle size, zeta potential, secondary structure, and antioxidant properties of the formed conjugates before and after HC treatment. The results showed that HC treatment could promote the interaction between catechin and SPI. At 2.0 mg/mL catechin concentration, HC treatment could increase the amount of catechin bound to SPI from (21.82 ± 0.18) to (62.55 ± 0.36) mg/g. Compared with the untreated sample, HC treatment enhanced the UV absorption intensity, weakened the fluorescence intensity, increased the average particle size, decreased the absolute value of the zeta potential and surface hydrophobicity, and reduced the free sulfhydryl and amino group contents. Additionally, HC treatment caused an increase in α-helix, β-turn, and random coil relative contents and a decrease in β-sheet relative content. Furthermore, after HC treatment, the antioxidant activity of the catechin-SPI conjugates was significantly enhanced. For the conjugate formed at 2.0 mg/mL catechin concentration, the 1,1-diphenyl-2-picrylhydrayl (DPPH) free radical scavenging capacity increased from (48.64 ± 1.24)% to (84.72 ± 0.12)%, the 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) cation radical scavenging capacity from (35.60 ± 1.21)% to (75.51 ± 0.79)%, and the ferric reducing power from 0.81 ± 0.02 to 1.52 ± 0.05. It can be seen that HC treatment can promote the combination of catechin and SPI, change the structural properties of the resulting conjugates, and enhance its antioxidant activity.

为提高大豆肽纳米颗粒（SPN）Pickering乳液稳定性，以大豆肽聚集体为原料，采用超声法制备SPN，对超声时间进行了优化；在SPN体系中引入大豆分离蛋白（SPI）构建复合乳化剂，研究不同乳化剂质量浓度下SPI对SPN界面活性和乳化稳定性的影响。结果表明：选取超声时间10 min制备SPN;随着乳化剂质量浓度的增大，乳液粒径逐渐减小，当乳化剂质量浓度较低（5 mg/mL）时，乳液出现桥联，乳化剂质量浓度过高（30 mg/mL）时则出现絮凝；界面蛋白吸附率随着乳化剂质量浓度的增加呈现先升高后降低的趋势。在相同乳化剂质量浓度下，添加SPI的SPN乳液（SPI-SPN乳液）的粒径分布峰左移，其粒径、界面蛋白吸附率显著小于SPN乳液的；在储存过程中，SPN乳液粒径逐渐增大，SPI-SPN乳液粒径没有显著变化；SPI-SPN乳液的乳析指数小于相同乳化剂质量浓度的SPN乳液，当乳化剂质量浓度为30 mg/mL时，储存15 d SPI-SPN乳液未出现分层现象。综上，SPI可以提高SPN的界面活性和SPN乳液储存过程中的絮凝稳定性和分层稳定性。In order to improve the stability of the Pickering emulsion of soy peptide nanoparticles (SPN), soy peptide aggregates were used as raw materials to prepare SPN by ultrasonic method, and the ultrasonic time was optimized. And then soy protein isolate (SPI) was introduced into the SPN system to construct a new composite emulsifier. The effects of SPI on the interface activity and emulsification stability of SPN under different emulsifier mass concentrations were studied. The results showed that SPN was prepared under the condition of ultrasonic time 10 min. With the increase of emulsifier mass concentration, the particle size of the emulsion decreased gradually. When the emulsifier mass concentration was low (5 mg/mL), the emulsion bridged, while when the emulsifier mass concentration was high (30 mg/mL), the emulsion flocculated. The adsorption rate of interfacial protein increased chiefly and then decreased with emulsifier mass concentration increasing. Under the same emulsifier mass concentration, the particle size distribution peak of the SPN emulsion with SPI (SPI-SPN emulsion) was shifted to the left, and the particle size and adsorption rate of interfacial protein were significantly smaller than the SPN emulsion. The particle size of the SPN emulsion gradually increased during storage, while the particle size of the SPI-SPN emulsion did not change significantly. The creaming index of SPI-SPN emulsion was smaller than that of SPN emulsion with the same emulsifier mass concentration. The SPI-SPN emulsion did not appear to cream after 15 d of storage when the emulsifier mass concentration was 30 mg/mL. In conclusion, SPI can improve the interfacial activity of SPN and the stability of flocculation and stratification of SPN emulsion during the storage.

In present scenario, much of the attention has been put on the production and utilization of Pickering emulsions deciphering enhanced stability and applicability over wide environmental conditions. In this context the present study was carried out to elaborate effect of different wall materials and pH systems on the physicochemical, structural and morphological properties of Himalayan walnut oil Pickering emulsions by ultrasonic emulsification. In this study, concentrated Pickering emulsion of Himalayan walnut oil (HWO) was prepared utilizing soy protein isolate (SPI), maltodextrin (MD) stabilized by pectin at varying concentrations and pH systems (4.0, 7.0). With increase in pectin and SPI concentration and lowering MD, stable emulsions were obtained as deciphered by an Emulsion stability index (ESI) of 100 for 7 days at ambient storage. HWO Pickering emulsions were analysed for particle size measurements (2.13–13.64 µm) and depicted negative zeta potential values (−3.70 to −18.58). Lyophilized HWO microcapsules depicted moderate encapsulation efficiency (44.69–57.63 %) whereas the hygroscopicity values of the microcapsule ranged from (0.21–12.10 %). Thermogravimetric analysis (TGA) of the samples depicted the temperature of maximum degradation rate up to 550 °C whereas XRD spectra depicted amorphous nature of oil microcapsules. FTIR spectra revealed a close association between the SPI-MD-Pectin matrix. SEM analysis revealed stable oil globules entrapped in protein-polysaccharide matrix with no visible cracks and fissures.

In the present study, the soy protein and whey protein isolates were hydrolysed using food-grade endoenzymes (papain and pancreatin) for different time periods (10, 30, 60, 90, and 120 min) at 35 °C. Several functional properties were examined at various times of hydrolysis. Papain hydrolysed both the isolates better than pancreatin throughout the hydrolysis period. The degree of hydrolysis of papain hydrolysed soy protein isolate was 1.12 after 120 min of hydrolysis. During the hydrolysis, the particle size of the isolates was decreased initially followed by slight increase. The particle size of whey protein isolate was higher than the soy protein isolate. Zeta potential was decreased during hydrolysis for both isolates. The particle size and zeta potential were inversely proportional to the degree of hydrolysis. SDS-PAGE has shown that, soy protein isolate had a greater number of peptide bands after hydrolysis than whey protein isolate. Emulsifying activity increased with hydrolysis time. Emulsion stability increased after enzyme addition and decreased with time. From this study it was evident that, enzymatic hydrolysis of defatted soy protein isolate enhances its functional properties. Hence, this hydrolysed soy protein isolate can be used as a cost-effective alternative to whey protein isolate, for vegans and patients.

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study analyses the formation of complexes between soy protein isolate (SPI) and phenolic compounds in hydro- ethanolic extract of pomegranate peel (ePGP) and the effects of protein- phenolic interaction on the structure and physicochemical properties of the protein. The complexes (SPI-ePGPs) were obtained under conditions of different pH: acidic (3.0, 4.0, 5.0), neutral (7.0) and alkaline (7.5 and 9.0), and with pre- treatment of SPI at a temperature of 90ºС and 25ºС. The formation of SPI-ePGPs was established by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulphate (SDS-PAGE) and UV- Vis spectroscopy. The results show that phenolic compounds change the structure of SPI, and they are most distinct in the alkali-treated SPI-ePGPs. The effect of the interaction between SPI macromolecules and phenolic compounds on protein solubility as well as foam formation and stability in SPI- ePGPs was monitored. In the complexes created, the phenolic compounds in ePGP did not increase the solubility of the protein, but had a positive effect on foaming. The research data provide a theoretical basis for creating methods for modifying soy protein and for developing new food and matrix systems for active substances in the pharmaceutical industry. [ABSTRACT FROM AUTHOR]

Oil bodies (OBs) are naturally occurring pre-emulsified oil droplets that have broad application prospects in emulsions and gels. The main purpose of this research was to examine the impact of the OB content on the structure and functional aspects of acid-mediated soy protein isolate (SPI) gel filled with OBs. The results indicated that the peanut oil body (POBs) content significantly affected the water holding capacity of the gel. The rheological and textural analyses showed that POBs reduced the gel strength and hardness. The scanning electron and confocal laser scanning microscopy analyses revealed that POBs aggregated during gel formation and reduced the gel network density. The Fourier transform infrared spectrum (FTIR) analysis demonstrated that POBs participated in protein gels through hydrogen bonds, steric hindrance and hydrophobic interactions. Therefore, OBs served as inactive filler in the acid-mediated protein gel, replaced traditional oils and provided alternative ingredients for the development of new emulsion-filled gels. [ABSTRACT FROM AUTHOR]

In this research, production films based on soy protein were produced with two variables of nanoclay at three levels (0, 0.5 and 1%) and Salvia officinalis Essential oil at three different levels (0, 250 and 500 ppm) and the effect of this Two variables were investigated on the functional, mechanical and structural characteristics of the produced biodegradable films. The results showed that by adding different percentages of nanoclay on the soy protein film substrate, the moisture content, solubility, permeability to water vapor and transparency of the samples decreased significantly compared to the control sample. This decrease in indicators was more evident with increasing concentration of Salvia officinalis Essential oil. Among the production samples, the film containing 1% nanoclay and 500 ppm of Salvia officinalis Essential oil had a water vapor permeability of 32.02×10-11 g/m.s.pa. Also, the addition of nanoclay and Salvia officinalis essential oil caused a significant increase in the antioxidant content of the samples, and the sample containing 1% nanoclay and 500 ppm of Salvia officinalis essential oil had the highest antioxidant content with 32.88%. Examining the results of spectroscopy and microstructure of the obtained films also shows the proper interaction between nanoparticle and essential oil with soy protein substrate and creating strong and new bonds. The obtained results showed that the addition of nanoclay and Salvia officinalis essential oil can have positive effects on the physical and structural properties of soy protein isolate film. [ABSTRACT FROM AUTHOR]