Legume Proteins Research Articles

Enhanced Oligopeptide and Free Tryptophan Release from Chickpea and Lentil Proteins: A Comparative Study of Enzymatic Modification with Bromelain, Ficin, and Papain

Plant-based foods offer a sustainable alternative to meet the growing protein demand. Legumes are the most promising of these, as they contain relatively high concentrations of protein, low digestible starch, and dietary fiber, as well as them possibly featuring low levels of fat. Enzymatically modified legume proteins provide us with tempting perspectives in terms of enhancing foods’ biological values. However, their bioavailability and digestibility are generally less sufficient than that of proteins of animal origin, which may be improved by well-tailored enzyme modification. In this study, the efficacy of three plant-based proteases (bromelain, ficin, and papain) were evaluated at two distinct concentrations (2.5% and 10%) and three hydrolysis durations (1, 2, and 12 h) when transforming chickpea and lentil proteins. The degree of hydrolysis (DH), peptide profiles, and free amino acid content were analyzed to determine the efficiency of each enzyme. Results showed significant variations in DH, which was influenced by enzyme type, concentration, and hydrolysis duration. Papain exhibited the highest DH, particularly at a 10% concentration, reaching 27.8% efficiency in chickpea and 34.8% in lentils after 12 h. Bromelain and ficin were proven to be less effective, with ficin showing the least hydrolytic activity. SDS-PAGE analysis revealed substantial protein degradation, especially subsequent to papain treatment, pointing out that most proteins were cleaved into smaller peptides. SEC-HPLC indicated a predominant release of peptides within the 200–1000 Da range, suggesting enhanced bioavailability. Papain and bromelain treatments resulted in a significant release of oligopeptides and dipeptides. UHPLC analysis highlighted a marked post-hydrolysis increase in total free amino acids, with arginine, leucine, and lysine being the most abundant ones. Notably, tryptophan, being undetectable in untreated samples, was released in measurable amounts post-hydrolysis. These findings demonstrate papain’s superior performance in protein hydrolysis and its potential in producing bioactive peptides, highlighting its applicability in food processing and the development of both nutraceuticals and functional foods.

The role of amylose content on the structure and rheological properties of pea protein-starch systems during pressurized hydrothermal processing

Legume proteins are often subjected to hydrothermal cooking in starch containing formulations. In this work we studied the formation of structure in mixed gels containing pea protein isolate (PPI) and three maize starch types (waxy, normal-amylose and high-amylose), distinct for their amylose content (0, 26 and 56%) and swelling properties. The starch, PPI and mixed hydrogels were processed at high moisture and high temperature, and the changes in apparent viscosity were followed in situ. The amylose content in starch granules was a key parameter determining micro-structure, water partitioning and mechanical properties of the mixed gels. PPI addition to high-amylose starch (HAMS) resulted in a delay of the onset of structure formation, measured by a build-up of viscosity, and reduced gelatinization. After heating, swollen and distorted granules were present, dispersed in a protein-dominated network. In this mixed gel, along with the greater resistance to swelling during gelatinization, there was a lower extent of retrogradation, less water migration, which also reduced the hardness increase during storage, compared to the other mixtures. In the gels containing waxy and normal-amylose starch, the microstructure denoted a starch-dominated network, with protein particles segregated in the interstitial spaces of the swollen gelatinized starch. The results well describe the dynamics of interactions occurring between these biopolymers, and are an important step towards understanding the importance of their interactions during hydrothermal cooking, highlighting the importance of phase formation during swelling.

The Critical Roles of Phosphatidylethanolamine-Binding Proteins in Legumes.

Legumes, characterized by their ability to form symbiotic relationships with nitrogen-fixing bacteria, play crucial roles in agriculture, ecology and human nutrition. Phosphatidylethanolamine-binding proteins (PEBPs) are the key genetic players that contribute to the diverse biological functions of legumes. In this review, we summarize the current understanding of important roles of PEBP genes in legumes, including flowering, inflorescence architecture, seed development and nodulation. We also delve into PEBP regulatory mechanisms and effects on plant growth, development, and adaptation to the environment. Furthermore, we highlight their potential biotechnological applications for crop improvement and promoting sustainable agriculture. This review emphasizes the multifaceted roles of PEBP genes, shedding light on their significance in legume biology and their potential for sustainable productive farming.

The Satiating Effect of Extruded Plant Protein Compared with Native Plant and Meat Protein in a Ragú “Bolognaise” Meal: A Randomized Cross-Over Study

Protein increases satiety by, among other things, increasing the content of certain amino acids in the blood. Plant proteins generally have a lower digestibility than meat proteins. The digestibility increases after extrusion; thereby, extrusion potentially also increases the satiating effect. We investigated subjective appetite and ad libitum energy intake (adlib_EI) following ragú “bolognaise” meals with three different protein sources. We hypothesized that the satiating effect of texturized vegetable proteins (TVP) was comparable to that of animal protein (Meat) and that TVPs would have a stronger satiating effect than non-texturized legume proteins (Green). Test meals were theoretically designed to be similar in weight, energy (kJ), macronutrients and fiber. The in vitro protein digestibility (IVPD) and the amino acid composition were analyzed. A randomized, single-blinded, three-way, cross-over study including 25 healthy men was carried out. There were no significant differences between the three meals in terms of subjective appetite. The adlib_EI was significantly lower after the TVP meal (758 kJ) than after the Meat meal (957 kJ), with the Green meal in between (903 kJ). The IVPD was significantly higher in the Meat meal (30.72%) than in the Green meal (20.17%), with the TVP meal in between (21.05%). In conclusion, the TVP meal had a higher long-term satiating effect than a similar meal with meat.

Effect of legume proteins on the structure and digestibility of wheat starch-lauric acid complexes

The effect of legume proteins (soy protein (SP), chickpea protein (CP) and peanut protein (PP)) on the properties of wheat starch-lauric acid (WS-LA) system and its intrinsic mechanism were investigated. RVA, digestion experiment and TGA results showed that legume proteins prompted the viscosity peak formation during cooling stage and increased anti-digestion and thermal stability of WS-LA system. FT-IR, Raman, XRD and 13C NMR results indicated that legume proteins improved the long-range and short-range ordering degree and single-helix structure of WS-LA system. SP had greater influence on the properties of WS-LA system than that of CP and PP. Proteins with high solubility, emulsifying properties and β-sheet content were conducive to starch-based complexes formation. Molecular dynamics simulation results indicated that major forces for WS-LA-SP formation were hydrogen bonding and van der Waals forces. This study offered crucial information on starch-fatty acid-protein complexes formation for proteins selection in starch-based products development.

Optimizing the fermentation parameters in the Lactic Acid Fermentation of Legume-based Beverages– a statistically based fermentation

BackgroundThe market for beverages is highly changing within the last years. Increasing consumer awareness towards healthier drinks led to the revival of traditional and the creation of innovative beverages. Various protein-rich legumes were used for milk analogues, which might be also valuable raw materials for refreshing, protein-rich beverages. However, no such applications have been marketed so far, which might be due to unpleasant organoleptic impressions like the legume-typical “beany” aroma. Lactic acid fermentation has already been proven to be a remedy to overcome this hindrance in consumer acceptance.ResultsIn this study, a statistically based approach was used to elucidate the impact of the fermentation parameters temperature, inoculum cell concentration, and methionine addition on the fermentation of lupine- and faba bean-based substrates. A total of 39 models were found and verified. The majority of these models indicate a strong impact of the temperature on the reduction of aldehydes connected to the “beany” impression (e.g., hexanal) and on the production of pleasantly perceived aroma compounds (e.g., β-damascenone). Positively, the addition of methionine had only minor impacts on the negatively associated sulfuric compounds methional, dimethyl sulfide, dimethyl disulfide, and dimethyl trisulfide. Moreover, in further fermentations, the time was added as an additional parameter. It was shown that the strains grew well, strongly acidified the both substrates (pH ≤ 4.0) within 6.5 h, and reached cell counts of > 9 log10 CFU/mL after 24 h. Notably, most of the aldehydes (like hexanal) were reduced within the first 6–7 h, whereas pleasant compounds like β-damascenone reached high concentrations especially in the later fermentation (approx. 24–48 h).ConclusionsOut of the fermentation parameters temperature, inoculum cell concentration, and methionine addition, the temperature had the highest influence on the observed aroma and taste active compounds. As the addition of methionine to compensate for the legume-typical deficit did not lead to an adverse effect, fortifying legume-based substrates with methionine should be considered to improve the bioavailability of the legume protein. Aldehydes, which are associated with the “beany” aroma impression, can be removed efficiently in fermentation. However, terminating the process prematurely would lead to an incomplete production of pleasant aroma compounds.

Legume protein gelation: The mechanism behind the formation of homogeneous and fractal gels

Protein gelation can provide texture in plant-based foods and can be influenced by many factors, including protein extraction method and salt addition. However, the protein gelation mechanism is still not well understood for plant proteins, especially for isolates obtained using commercial protein extraction processes. Therefore, the structural changes that legume sources such as yellow pea, faba bean, and soybeans undergo during the gelation process to understand the differences in their gelation mechanisms was investigated herein by using small-angle neutron scattering. Among these protein sources, the commercial extraction method was found to play a major part in the gelation pathway. Intensive protein extraction methods involving isoelectric precipitation led to lower protein solubility (∼1–38% w/w), larger insoluble protein particle sizes (60–100 μm), and a gelation pathway that is dependent on the changes of the insoluble protein particles. In contrast, extraction using ultrafiltration instead of precipitation resulted in higher protein solubility (∼18–88% w/w) and smaller insoluble protein particle sizes (40–70 μm), and the structural changes observed during gelation involved the structural changes of both soluble proteins and insoluble proteins. SEM imaging also showed different gel networks, with fractal networks formed by insoluble proteins (for sources with low solubility) or more homogenous networks formed by the interactions between the soluble proteins (for sources with high solubility). Despite the differences observed in the gelation network and the protein solubility, the gelation strength exhibited by protein sources at low protein solubility were similar to the ones by protein sources at high protein solubility, demonstrating the potential of fractal gel networks in providing texture.

Unraveling the fate of mycotoxins during the production of legume protein and other derived products

Consumers are increasingly looking for healthier and sustainable diets. Plant-based diets rich in legumes satisfy this demand. Legumes contain protein, dietary fibers and starch. Technological processes can separate these fractions, which can be used as supplements, or as ingredients. Nonetheless, legumes are susceptible to fungal infection, causing a potential health concern, since some fungi can produce mycotoxins: toxic secondary metabolites. The aim of this work was to analyze the fate of mycotoxins during different stages of the production process of legume derived products from the raw materials to final products. An extraction followed by liquid chromatography-tandem mass spectrometry was used for the analysis, revealing the presence of enniatin B (ENN B), alternariol monomethyl ether (AME), deoxynivalenol, T2-toxin, nivalenol, fumonisin B1 and sterigmatocystin in raw materials, intermediate products and side streams. The alkaline solubilization steps, were effective in reducing ENN B; however, AME was found in one of the final products.

Comparison of Colorimetric Methods for Measuring the Solubility of Legume Proteins.

Increasing the use of plant proteins in foods requires improving their physical and chemical properties, such as emulsification, gelation capacity, and thermal stability. These properties determine the acceptability and functionality of food products. Higher protein solubility significantly impacts these properties by affecting denaturation and the stability of emulsifiers or gels. Therefore, developing plant-based protein ingredients requires accurately and conveniently measuring their solubility. Colorimetric solubility methods overcome many issues of more robust combustion and titration methods, but complicated chemical mechanisms limit their applicability for certain proteins. This study aims to compare the effectiveness of four common colorimetric solubility measurement methods for pulse and non-pulse legume proteins and hydrolysates. Pea, chickpea, lentil, and soy protein isolates were made from defatted flour and their solubility at a range of pHs was measured using the Bradford, Lowry, bicinchoninic acid (BCA), and biuret methods. Solubility was also measured for chickpea and soy protein hydrolysates made using Alcalase and Flavourzyme. A comparison of the methods for solubility quantification revealed that the Bradford and Lowry methods most closely match the expected results for the unhydrolyzed protein, with the BCA and biuret methods underestimating solubility by 30%. The Lowry method was the preferred method for hydrolysate solubility measurement, with the Bradford method measuring 0% solubility at the isoelectric point due to an inability to interact with peptides that are soluble at this pH. This study identifies reliable methods for measuring plant protein solubility that establish uniform outcomes and enable a better comparison across studies, giving a consensus for key functional properties in food applications.

Effect of Germination on the Digestion of Legume Proteins.

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

Masterly substitution of plant proteins can achieve acceptable sensory and nutritional attributes in meat-reduced surimi gel

Mixing surimi/plant proteins to reduce animal proteins is considered as an effective way to improve the sustainable production of surimi-based products. The effect of partial substitution (10%∼50%, plant proteins/surimi proteins ratio) of surimi proteins by plant proteins (wheat protein, soybean protein, rice protein, and pea protein) on the properties of the composite gels were investigated. The replacement caused the reductions in gel strength and whiteness. There was a slight increase in water holding capacity (WHC) of mixed gels made from soy or pea protein, but decrease in the cereal protein group. E-nose investigations revealed that the reactions to the W5S and W1W sensors caused the scent profiles to shift dramatically as the replacement amount increased. Organoleptic inspection revealed the substitution ratios of wheat protein, soy protein, rice protein, and pea protein to achieve the sensorial rejection were 30%, 40%, 30%, and 40%, respectively. LF-NMR and MRI showed the cereal proteins increased the T22 relaxation time, while the legume proteins caused a reduction. The mixed gels contained all the essential amino acid, and the digestibility in the wheat protein groups was the highest. These results proved an elaborate formulation can achieve balanced sensory and nutritional attributes in surimi gelled foods.

One-step purification and characterization of a haloprotease from Micrococcus sp. PC7 for the production of protein hydrolysates from Andean legumes.

The high content and quality of protein in Andean legumes make them valuable for producing protein hydrolysates using proteases from bacteria isolated from extreme environments. This study aimed to carry out a single-step purification of a haloprotease from Micrococcus sp. PC7 isolated from Peru salterns. In addition, characterize and apply the enzyme for the production of bioactive protein hydrolysates from underutilized Andean legumes. The PC7 protease was fully purified using only tangential flow filtration (TFF) and exhibited maximum activity at pH 7.5 and 40°C. It was characterized as a serine protease with an estimated molecular weight of 130kDa. PC7 activity was enhanced by Cu2+ (1.7-fold) and remained active in the presence of most surfactants and acetonitrile. Furthermore, it stayed completely active up to 6% NaCl and kept ̴ 60% of its activity up to 8%. The protease maintained over 50% of its activity at 25°C and 40°C and over 70% at pH from 6 to 10 for up to 24h. The determined Km and Vmax were 0.1098mg mL-1 and 273.7 U mL-1, respectively. PC7 protease hydrolyzed 43%, 22% and 11% of the Lupinus mutabilis, Phaseolus lunatus and Erythrina edulis protein concentrates, respectively. Likewise, the hydrolysates from Lupinus mutabilis and Erythrina edulis presented the maximum antioxidant and antihypertensive activities, respectively. Our results demonstrated the feasibility of a simple purification step for the PC7 protease and its potential to be applied in industrial and biotechnological processes. Bioactive protein hydrolysates produced from Andean legumes may lead to the development of nutraceuticals and functional foods contributing to address some United Nations Sustainable Development Goals (SDGs).

Insight into the Effect of Extraction and Spray Drying Conditions on the Nutritional and Techno-Functional Properties of Legume Protein Powder: A Review

Insight into the Effect of Extraction and Spray Drying Conditions on the Nutritional and Techno-Functional Properties of Legume Protein Powder: A Review

Mixing oat proteins with lentil or faba bean proteins: How is the techno-functional behavior of the different protein systems affected by heat treatments?

Despite the growing market for plant-based products, rarely a single plant protein source manages to provide all the essential amino acids in a balanced way. Mixed protein systems combining proteins from more than one plant source may be useful to overcome this drawback. However, the mixture of proteins from different plant sources may impact the technological performance of the system. In this context, the influence of heat treatments of 75 and 95 °C for 15 min at neutral pH on the colloidal and the techno-functional properties of mixtures of protein isolates from lentil and oat (LO) and from faba bean and oat (FO) were investigated. The applied heat treatments induced subtle changes in the colloidal properties of the different systems. It was evidenced by size exclusion chromatography that oat proteins were more prone to heat induced changes than lentil or faba bean proteins. Regarding the techno-functional properties, mixing the proteins from the different sources had an antagonistic effect on foamability. On the other hand, an additive effect was observed for emulsifying capacities, with legume proteins displaying values between 93 and 100%, oat proteins close to 65%, and mixed systems between 78 and 93 %. Vicilin (7S) and β-basic subunits of legumin (11S) from lentil and faba bean, and oat 12S globulin were the main protein fractions stabilizing the interface of the obtained emulsions. The proteins from both sources coexisted at the interface of the emulsions stabilized by the mixed systems. The microstructure of the thermo-induced gels was dictated by oat proteins. However, the different legumes played a determining role in the critical gelling concentration measured (8 % w/w and 11.5 % w/w respectively for LO and FO). Mixing oat proteins with lentil or faba bean proteins allows modulating the techno-functional performance of the systems, thus represents an opportunity for innovative applications.

Identification of differentially expressed genes controlling the expression of flowering in Bambara groundnut (Vigna subterranea [L.] Verdc.)

Bambara groundnut flowering is a crucial developmental stage in the vegetative to reproductive period. The earliness to lateness of flowering is regulated by various interconnected genetic pathways encoded by genes. Deoxyribonucleic acid (DNA) of the selected accessions was extracted through leaf samples at 3 weeks old, using Dellaporta Miniprep for Plant DNA Isolation procedure. The high-quality DNA was sequenced using Diversity Arrays Technology (DArT) markers and single nucleotide polymorphisms (SNP’s) associated with flowering was identified. There is need to investigate the genetic make-up of the cleistogamous flower of Bambara through associated genes for improvement. This research work identified four markers associated with the flowering of Vigna subterranea and the role of variant identified genes in flowering. The identified markers from the sequence and the selected amino acid sequence were used as a query to search the legume protein database in Vigna radiata. The four markers with adequate information associated with flowering in the sequence were 24385352|F|0–28:T > C-28:T > C; 27641816|F|0–17:C > T-17:C > T; 24384204|F|0–24:C > T-24:C > T and 24346601|F|0–67:T > C-67:T > C and significant at P < 1.68 × 10−4 at chromosomes 7, 11, 4, and 5. The identified genes including histones, Polyketide, cyclase/dehydrase, Transcription factor MYC/MYB N-terminal, Rhamnogalacturonate lyase, DHHC-type zinc finger protein, Putative S-adenosyl-L-methionine-dependent methyltransferase, Ribosomal protein L2, D-galactoside/L-rhamnose binding SUEL lectin domain, Lipase GDSL, Histone deacetylase superfamily, Basic-leucine zipper domain, TUP1-like enhancer of split, Zinc finger ZZ-type, Homeodomain-like, Phosphatidylethanolamine-binding protein PEBP, Leucine-rich repeat which are tools in controlling flowering in Bambara groundnut. This study revealed that Bambara groundnut flowering is controlled by the interplay of genes.

Exploring the potential of mushrooms in ready‐to‐eat snack formulations

SummaryContemporary dining habits have spurred a shift in ready‐to‐eat (RTE) snack production, with mushrooms offering a nutritional boost due to their protein, carbohydrate, fibre and vitamin content. Proximate composition data aid in creating snacks with balanced nutrition. Mushrooms also contribute antioxidants and antimicrobial compounds, adding a health dimension. Extrusion cooking, known for adaptability and energy efficiency, improves texture, nutrition and shelf life. Though concerns exist about oil intake, frying remains popular for taste and consistency enhancement, requiring careful management. Baking extends shelf life and preserves flavour while enhancing nutrient availability. Various studies highlight the potential of these techniques to meet consumer preferences for convenient, appealing and health‐conscious snacks by incorporating ingredients like legume protein isolates, nuts and seeds, etc. The RTE snack industry evolves to provide healthier options driven by technological innovations and sustainability practices, with personalised and functional snacks on the horizon. The study aims to explore and highlight the nutritional benefits of incorporating mushrooms into RTE snacks and discusses the unique advantages of extrusion, frying and baking in snack production.

Effects of combined hot alkaline and pH-shift treatments on structure and functionality of legume protein-EGCG conjugates: Soybean-, pea-, and chickpea protein-EGCG systems

Legume proteins are appealing in the food industry for their nutrition and sustainability, but their low solubility due to the compact structure makes their applications in food industry limited. In this study, three commonly used legume proteins in food industry were selected as samples to be tested: soy protein (SP), pea protein (PP), and chickpea protein (CP). This study aims to improve the structural properties of these three proteins, so that it could promote effective grafting with epigallocatechin gallate (EGCG) through a combined hot alkaline and pH-shift treatments. Legume protein solutions were adjusted to pH 12 and heated at 80 °C for 30 min, resulting to a 13%–19% increase in free thiol content and a 59%–610% increase in surface hydrophobicity. This kind of change in structure leads to a 19%–46% increase in EGCG grafting degree. Treated protein-EGCG conjugates exhibited smaller and more uniform particle sizes, improved emulsification activity by 27%–218%, and additionally enhanced solubility, thermal stability, and antioxidant activity. Among all the tested proteins, pre-treated SP-EGCG conjugates showed the best solubility, emulsification, and thermal stability due to their highest surface hydrophobicity, highest EGCG grafting degree, and loose structure. These results indicate that combined hot alkaline and pH-shift treatment enhances the functional properties of legume proteins, expanding their potential applications as functional ingredients in the food industry.

Optimizing Screw Speed and Barrel Temperature for Textural and Nutritional Improvement of Soy-Based High-Moisture Extrudates.

Soy remains the legume protein of excellence for plant-based meat alternatives due to its fiber-forming potential. In this study, protein-rich powders from soy protein isolate (SPI), concentrate (SPC), and their mixture (SPM) were thoroughly characterized for their proximate composition, nutritional quality, and physicochemical properties to understand their structuring behavior during high-moisture extrusion. SPI presented higher degrees of protein denaturation and aggregation, least gelation concentration and lower essential amino acid contents. Thus, an SPI:SPC combination (1:9 ratio, 70% protein) was extruded at three different screw speeds (300, 350, and 400 rpm) and two temperature profiles (120 and 140 °C maximum temperature). The effects of the processing parameters on the extrudates were evaluated for their appearance (fibrousness), texture (TPA, cutting force, and anisotropy), color, protein structure (FTIR), and trypsin inhibitors. Higher temperatures resulted in softer and darker extrudates, with increased visual and instrumental anisotropy. Increasing screw speeds led to softer and lighter extrudates, without a clear fibrousness effect. β-sheet structures decreased and intermolecular aggregates (A1) increased after extrusion, especially at 140 °C, together with the formation of intramolecular aggregates (A2). Extrusion also significantly decreased the amount of trypsin inhibitors (>90%). This study demonstrates that extrusion parameters need to be carefully selected to achieve meat analogs with optimal textural and nutritional characteristics.

Combination of legume proteins and arabinoxylans are efficient emulsifiers to promote vitamin E bioaccessibility during digestion

The emulsification potential of plant-based emulsifiers, that is, pea (PPI) and lentil (LPI) proteins (4%), corn arabinoxylans (CAX, 1%), and legume protein-arabinoxylan mixtures (4% proteins + 0.15 or 0.9% CAX), was evaluated by assessing: the surface tension and potential of emulsifiers, emulsifier antinutritional contents, emulsion droplet size, emulsion physical stability, and vitamin E bioaccessibility from 10% oil-in-water emulsions. Tween 80 (2%) was used as a control. All emulsions presented small droplet sizes, both fresh and upon storage, except 4% LPI + 0.9% CAX emulsion that exhibited bigger droplet sizes (d(4,3) of approximately 18.76 μm vs 0.59 μm for the control) because of droplet bridging. Vitamin E bioaccessibility from emulsions stabilized with the combination of 4% PPI and either 0.15% or 0.9% CAX (28 ± 4.48% and 28.42 ± 3.87%, respectively) was not significantly different from that of emulsions stabilized with Tween 80 (43.56 ± 3.71%), whereas vitamin E bioaccessibility from emulsions stabilized with individual emulsifiers was significantly lower.

Investigating the Nutritional and Functional Properties of Protaetia brevitarsis Larvae and Isolated Soy Protein Mixtures as Alternative Protein Sources.

The growing demand for sustainable and alternative protein sources has spurred interest in insect-based and plant-based proteins. Protaetia brevitarsis (PB) larvae and isolated soy protein (ISP) are notable in this regard, offering potential health benefits and nutritional enhancements. We assessed the feasibility of PB larvae and ISP mixtures as alternative food ingredients. Methods included the optimized purification and freeze-drying of PB larvae, extraction and refinement of legume proteins, physicochemical and antioxidant capacity evaluations, DPPH radical scavenging activity measurement, total phenolic and flavonoids content quantification, general component analysis, amino acid profiling using HPLC, fatty acid profiling through gas chromatography, and mineral content analysis using inductively coupled plasma spectrometry. The study found that certain PB:ISP ratios, particularly a 7:3 ratio, significantly improved the blend's antioxidant capacity, as evidenced by DPPH scavenging activity. This ratio also impacted the nutritional profile by altering the mixture's general components, with a notable increase in moisture, crude protein, and fiber and a decrease in crude fat and ash. Amino acid analysis revealed a balanced presence of essential and non-essential amino acids. The fatty acid profile was rich in unsaturated fatty acids, especially in certain ratios. Mineral analysis showed a complex interplay between PB larvae and ISP, with some minerals decreasing and others increasing in the blend. PB larvae and ISP mixtures have significant potential as alternative protein sources, offering a diversified nutritional profile and enhanced antioxidant properties. The 7:3 ratio of PB larvae to ISP has been shown to be particularly effective, suggesting that this ratio may offer an optimal balance for enhancing the overall nutritional quality of the mixture. This study sets the stage for future research to further explore and optimize the potential of these mixtures for human consumption while considering the challenges of consumer acceptance and long-term safety.