Brown Rice Protein

Protein bars are widely consumed functional snacks, yet their stability and sensory quality can deteriorate during storage. This study examined the impact of incorporating aqueous and ethanolic rice bran extracts-rich sources of phenolic compounds with antioxidant and antimicrobial properties-into brown-rice-based protein bars and evaluated their quality, molecular characteristics, and functional performance. Ethanolic extract, which contained 1.85-fold higher total phenolics than the aqueous extract, produced the most pronounced improvements. Bars fortified with 1% ethanolic extract showed a 37.27% increase in DPPH radical scavenging activity and a 25.74% increase in ferric reducing antioxidant power reducing power compared to the control, alongside a 46.6% reduction in peroxide value, demonstrating enhanced oxidative stability. These molecular effects translated into favorable textural changes, including a 53.63% reduction in hardness and a 28.35% decrease in gumminess, accompanied by an 8.55% improvement in overall sensory acceptability. FTIR spectroscopy demonstrated meaningful alterations in secondary structures, including reduced α-helix content and increased β-turn and random coil proportions in ethanolic treatments, indicating partial protein unfolding. These molecular changes corresponded strongly with texture and sensory improvements, as confirmed by multivariate analyses (Principal Component Analysis and Partial Least Squares Regression). Collectively, the results highlight that ethanolic rice bran extract more effectively enhances antioxidant performance, structural properties, and consumer acceptability than aqueous extract. The findings not only underscore its potential as a natural preservative and functional ingredient in high-protein snacks but also support the valorization of rice bran as a sustainable source of nutraceutical compounds. © 2026 The Author(s). Food Science & Nutrition published by Wiley Periodicals LLC.

Hydrocolloids have proven effective in improving the texture of surimi gels, yet their application in plant-based seafood analogues remains underexplored. This study aimed to develop a hydrocolloid blend comprising methylcellulose (MC), curdlan gum (CG), and high-acyl gellan gum (GG) to achieve a surimi-like texture in plant-based fish cakes (PBFC) made from brown rice and pea protein isolates. The research showcased that higher MC concentration boosted protein powder's heated oil holding capacity, while CG concentration increments lowered it. However, heated water holding capacity remained stable despite changes in MC and GG levels. Incorporating hydrocolloids elevated PBFC moisture content, decreasing expressible moisture and oil amounts with rising MC, CG and GG concentrations. PBFC hardness increased with higher hydrocolloid levels and was influenced by temperature, while springiness remained unaffected. GG helped maintain storage modulus (G') during PBFC cooling at higher concentrations, whereas the opposite effect was observed for MC. Analytically, higher MC concentrations reduced protein digestibility, while increased GG concentrations appeared to enhance it. Microstructural analysis corroborated these findings, with more protein aggregates in PBFC containing 3.8% MC and fewer in PBFCs with 6% CG and 3% GG. Consumer evaluations indicated that PBFC formulated with 1% MC, 3% CG, and 1.5% GG matched the springiness of commercial surimi-tofu fish cake, though it received slightly lower overall liking scores. In conclusion, the combined use of these three hydrocolloids demonstrated the potential to enhance the physical properties of PBFC and modify protein digestibility, offering insights into the development of innovative plant-based seafood analogues. © 2024 The Authors. Published by Elsevier B.V.

A lean meat batter system was mixed with four plant proteins at 3, 6, 9, and 12% (w/w): pea protein A (PA), pea protein B (PB), brown rice protein (BR) and faba bean protein (FB). Texture profile analysis (TPA) revealed that increasing plant protein levels hardened the hybrid meat batters, with PA and PB leading to the hardest gels. TPA results were supported by micrographs, demonstrating that the two pea proteins formed large aggregates, contributing to a firmer hybrid meat gel. Dynamic rheology showed that the incorporation of plant proteins lowered the storage modulus (G') during the heating stage (20 to 72°C), yet the 6% PA treatment produced a final G' (after cooling) closest to the control (CL). Nuclear Magnetic Resonance (NMR) T2 relaxometry also demonstrated that plant proteins reduced the water mobility in hybrid meat batters. Results were in line with the cooking loss, except for a higher cooking loss in the BR formulation compared to the CL. Color measurement showed that increasing plant protein levels led to darker and yellower meat batters; however, the effect on redness varied among treatments. Overall, the findings suggest that pea proteins have superior functionality and compatibility within a lean poultry meat protein system, compared to BR and FB tested here.

BACKGROUND: Rapeseed protein isolate is used in the food industry, and heating is often used during rapeseed processing. However, the digestible indispensable amino acid score (DIAAS) for heat-treated rapeseed protein isolate is unknown. The present study aimed to test the hypothesis that heating rapeseed protein isolate improves protein quality resulting in DIAAS that is greater than for pea and rice protein concentrates, and comparable to that of soy and whey protein isolates. RESULTS: Standardized ileal digestibility (SID) of amino acids (AA), except leucine and methionine, was not different between heat-treated rapeseed protein isolate and soy protein isolate, but SID of most AA was greater (P < 0.001) for heat-treated rapeseed protein isolate than for brown rice protein concentrate, pea protein concentrate, rapeseed protein isolate and soy protein isolate, but not whey protein isolate. Non-heated rapeseed protein isolate had a reduced (P < 0.001) DIAAS for 6-month-old to 3-year-old children compared with soy protein isolate, but this was greater (P < 0.001) than for pea and brown rice protein concentrates. The DIAAS for heat-treated rapeseed protein isolate was greater (P < 0.001) than for non-heated rapeseed protein isolate for all age groups. Heat-treated rapeseed protein isolate and whey protein isolate had a DIAAS > 100 for individuals older than 3 years. CONCLUSION: Rapeseed protein isolate had a DIAAS comparable to soy protein isolate, but heat-treated rapeseed protein isolate and whey protein isolate had DIAAS ≥ 100, qualifying these proteins as 'excellent'. Rice and pea protein concentrates had DIAAS < 75. © 2023 Society of Chemical Industry. © 2023 Society of Chemical Industry.

Proteins are widely used in the formation and stabilization of multiphase systems, thanks to their ability to adsorb at the interface reducing the interfacial tension and promoting the formation of viscoelastic layers. Owing to the growing consumer demand, the food industry is moving toward the growing use of plant-based proteins, suitable for consumers who do not eat products of animal origin, for either ethical or health reasons. Nevertheless, the scientific literature lacks information on the surface activity and emulsifying ability of these proteins. In this work, the interfacial properties of soy, hemp and brown rice isolate proteins were investigated at the interface with commercial sunflower oil (O/W) to evaluate their characteristics in view of potential uses in food applications such as emulsions, sauces, dressing, topping and soft foods. Dilatational and shear kinematic, with pendant drop and magnetic rod techniques, respectively, were used. The dilatational analysis was performed in static and dynamic conditions, to obtain the equilibrium adsorption isotherms and the rheological parameters of the interfacial layers under both oscillation and stress relaxation. The interfaces were studied in shear conditions with small amplitude oscillations and creep tests. The obtained results evidenced that all tested proteins are able to build a strong viscoelastic layer with properties comparable to those of animal proteins. Brown rice protein seems particularly effective in reducing the interfacial tension even if shear tests evidence that the interface is weaker than that obtained using hemp or soy protein. Hemp protein seems very promising for potential practical uses yielding intermediate interfacial tensions and strong viscoelastic layers.

Plant-based proteins are very often used as carriers of different phenolic compounds. For that purpose, complexation of quercetin with almond and brown rice protein matrices was investigated. The amount of protein matrices was constant, while the concentration of quercetin varied (1 mM, 2 mM or 5 mM) during complexation. Dried complexes were investigated for quercetin amount (HPLC analysis) and antioxidant activity (DPPH, FRAP and CUPRAC methods). Additionally, complexation was proven by DSC and FTIR-ATR screening. An increase in the concentration of quercetin in the initial complexation mixture resulted in the increase in the adsorption of quercetin onto protein matrices. For the brown rice protein matrices, this increase was proportional to the initial quercetin concentration. Adsorption of quercetin caused the change in thermal stability of microparticles in comparison to corresponding protein matrices that have been proven by DSC. FTIR-ATR analysis revealed structural changes on microparticles upon adsorption of quercetin.

Four antioxidant peptides (Ile-Tyr, Leu-Tyr, Val-Tyr, and Tyr-Leu-Ala), identified from brown rice protein hydrolysates, showed strong ROO· and ABTS·+ scavenging activities. Changes in the antioxidant activity of peptides and GSH (control) under different processing conditions, namely, NaCl, temperature, pH, and gastrointestinal proteases, were evaluated by the oxygen radical absorbance capacity assay and the Trolox equivalent antioxidant capacity assay. Results indicated that with the increase in NaCl concentration, temperature, and pH (beyond neutral), the antioxidant activity of the peptides decreased, while the decrease was lower than that of GSH. The antioxidant activity of the four antioxidant peptides changed slightly after in vitro digestion, indicating a relatively high digestion resistance. The protective effect on the oxidative damage model of 2,2-azobis (2-methylpropionamide)-dihydrochloride-induced human red blood cells was also studied. Leu-Tyr and Tyr-Leu-Ala could alleviate but not totally inhibit oxidative damage in red blood cells, and their protective effects were dependent on concentration.

Sustainable crop production for a rapidly growing human population is one of the current challenges faced by the agricultural sector. However, many of the chemical agents used in agriculture can be hazardous to humans, non-targeted organism and environment. Plant growth promoting rhizobacteria have demonstrated a role in promoting plant growth and health under various stress conditions including disease. Unfortunately, bacterial viability degrades due to temperature and other environmental factors (Bashan et al., Plant Soil 378: 1-33, 2014). Encapsulation of bacteria into core-shell biopolymers is one of the promising techniques to overcome the problem. This study deals with the encapsulation of Bacillus salmalaya 139SI using simple double coating biopolymer technique which consist of brown rice protein/alginate and 0·5% low molecular weight chitosan of pH 4 and 6. The influence of biopolymer to bacteria mass ratio and the chitosan pH on the encapsulation process, physic-chemical, morphology and bioactivity properties of encapsulated B. salmalaya 139SI have been studied systematically. Based on the analysis of physico-chemical, morphology and bioactivity properties, B. salmalaya 139S1 encapsulated using double coating encapsulation technology has promising viability pre- and postfreeze-drying with excellent encapsulation yields of 99·7 and 89·3% respectively. SIGNIFICANCE AND IMPACT OF THE STUDY: The need of a simple yet effective way of encapsulating plant growth promoting rhizobacteria is crucial to further improve their benefits to global sustainable agriculture practice. Effective encapsulation allows for protection, controlled release and function of the micro-organism, as well as providing a longer shelf life for the product. This research report offers an innovative yet simple way of encapsulating using double coating technology with environmentally friendly biopolymers that could degrade and provide nutrients when in soil. Importantly, the bioactivity of the bacteria is maintained upon encapsulation. © 2018 The Society for Applied Microbiology.

The physiological effects of the hydrolysates of white rice protein (WRP), brown rice protein (BRP), and soy protein (SP) hydrolyzed by the food grade enzyme, alcalase2.4 L, were compared to the original protein source. Male Syrian Golden hamsters were fed high-fat diets containing either 20% casein (control) or 20% extracted proteins or their hydrolysates as the protein source for 3 weeks. The brown rice protein hydrolysate (BRPH) diet group reduced weight gain 76% compared with the control. Animals fed the BRPH supplemented diet also had lower final body weight, liver weight, very low density lipoprotein cholesterol (VLDL-C), and liver cholesterol, and higher fecal fat and bile acid excretion than the control. Expression levels of hepatic genes for lipid oxidation, PPARα, ACOX1, and CPT1, were highest for hamsters fed the BRPH supplemented diet. Expression of CYP7A1, the gene regulating bile acid synthesis, was higher in all test groups. Expression of CYP51, a gene coding for an enzyme involved in cholesterol synthesis, was highest in the BRPH diet group. The results suggest that BRPH includes unique peptides that reduce weight gain and hepatic cholesterol synthesis.

The effects of nitrogen fertilizer treatment and source (prilled urea, urea supergranule, fresh azolla, rice straw or sesbania or rice straw compost and their combinations) on grain quality were studied in the 1987 crops of variety IR64 at IRRI. Although fertilizer application improved grain yield, it improved protein content only in the case of urea supergranule, azolla and rice straw. Lysine contents of brown rice protein were similar in samples with no N fertilizer and those with the highest protein content in both seasons. Fertilizer treatment regardless of source tended to decrease weight and increase translucency of brown rice in both seasons. Effects on other grain properties were not consistent in both seasons. Season affected more grain properties than fertilizer treatment did, particularly translucency which was higher in the dry season than in the wet season.

A protein concentrate (Oryzatein-80™) and a protein isolate (Oryzatein-90™) from organic whole-grain brown rice were analyzed for their amino acid composition. Two samples from different batches of Oryzatein-90™ and one sample of Oryzatein-80™ were provided by Axiom Foods (Los Angeles, CA, USA). Preparation and analysis was carried out by Covance Laboratories (Madison, WI, USA). After hydrolysis in 6-N hydrochloric acid for 24 h at approximately 110 °C and further chemical stabilization, samples were analyzed by HPLC after pre-injection derivitization. Total amino acid content of both the isolate and the concentrate was approximately 78% by weight with 36% essential amino acids and 18% branched-chain amino acids. These results are similar to the profiles of raw and cooked brown rice except in the case of glutamic acid which was 3% lower in the isolate and concentrate. The amino acid content and profile of the Oryzatein-90™ isolate was similar to published values for soy protein isolate but the total, essential, and branched-chain amino acid content of whey protein isolate was 20%, 39% and 33% greater, respectively, than that of Oryzatein-90™. These results provide a valuable addition to the nutrient database of protein isolates and concentrates from cereal grains.

Reducing meat consumption reduces carbon emissions and other environmental harms. Unfortunately, commercial plant-based meat substitutes have not seen widespread adoption. In order to enable more flexible processing methods, this paper analyzes the characteristics of commercially available spirulina, soy, pea, and brown rice protein isolates to provide data for nonmeat protein processing that can lead to cost reductions. The thermal and rheological properties, as well as viscosity, density, and particle size distribution, were analyzed for further study into alternative protein-based food processing. The differential scanning calorimetry analysis produced dry amorphous-shaped curves and paste curves with a more distinct endothermic peak. The extracted linear temperature ranges for processing within food production were 70-90 °C for spirulina, 87-116 °C for soy protein, 67-77 °C for pea protein, and 87-97 °C for brown rice protein. The viscosity analysis determined that each protein material was shear-thinning and that viscosity increased with decreased water concentration, with rice being an exception to the latter trend. The obtained viscosity range for spirulina was 15,100-78,000 cP, 3200-80,000 cP for soy protein, 1400-32,700 cP for pea protein, and 600-3500 cP for brown rice protein. The results indicate that extrusion is a viable method for the further processing of protein isolates, as this technique has a large temperature operating range and variable screw speed. The data provided here can be used to make single or multi-component protein substitutes.

Plant-based protein sources as a sustainable alternative to animal sources are highly relevant for food and dietary supplements industries. Plant proteins are becoming popular as an eco-friendly source for meeting global protein requirements due to their importance in nutrition, management of metabolic diseases, biological activities, functionality in processed food products and their low carbon footprints. We applied biochemical protein extraction protocol and prepared protein concentrate from an underutilised cereal, foxtail millet, with plausible applications in foods and supplements. Herein efforts were utilised to obtain foxtail millet protein (FMP) concentrate by means of standardisation of processes of extraction cum isolation. The conditions including flour to solvent ratio, extraction-precipitation pH, dissolution time, etc. were optimised to significantly improve protein yield and recovery. The FMP concentrate prepared was also analysed for nutritional composition, bioactive compounds, amino acid content and digestion properties in comparison to packaged brown rice protein concentrate. The protein concentrate prepared was found to have high digestibility, rich in essential amino acids with good phenolic and flavonoid content, thereby making it a potential sensory and antioxidant additive for food/pharmaceutical applications.

Plant-based protein sources have a characteristic aroma that limits their usage in various meat-alternative formulations. Despite being the most popular plant-based protein, the allergenicity of soy protein severely restricts the potential adoption of soy protein as an animal substitute. Thereby, allergen-free plant-protein sources need to be characterized. Herein, we demonstrate a rapid solid-phase-microextraction gas-chromatography/mass-spectrometry (SPME-GC/MS) technique for comparing the volatile aroma profile concentration of two different allergen-free plant-protein sources (brown rice and pea) and comparing them with soy protein. The extraction procedure consisted of making a 1:7 w/v aqueous plant protein slurry, and then absorbing the volatile compounds on an SPME fibre under agitation for 10 min at 40 °C, which was subsequently injected onto a GC column coupled to an MS system. Observed volatile concentrations were used in conjunction with odour threshold values to generate a Total Volatile Aroma Score for each protein sample. A total of 76 volatile compounds were identified. Aldehydes and furans were determined to be the most dominant volatiles present in the plant proteins. Both brown rice protein and pea protein contained 64% aldehydes and 18% furans, with minor contents of alcohols, ketones and other compounds. On the other hand, soy protein consisted of fewer aldehydes (46%), but a more significant proportion of furans (42%). However, in terms of total concentration, brown rice protein contained the highest intensity and number of volatile compounds. Based on the calculated odour activity values of the detected compounds, our study concludes that pea proteins could be used as a suitable alternative to soy proteins in applications for allergen-free vegan protein products without interfering with the taste or flavour of the product.