Impact of rutin-protein nanoparticles on extruded recombinant rice: structure, digestibility and in vitro fermentation.

Protein–β-Glucan Nanoparticle-Enriched Peach Juice: In Vitro Bioaccessibility, Metabolic Enzyme Inhibition, and Sensory Evaluation

This study introduces a novel food-grade protein–β-glucan nanoparticle system based on Fusarium venenatum protein isolate and Fuscoporia torulosa β-glucans, designed as a multifunctional ingredient for improving the physicochemical stability, bioaccessibility, and functional performance of peach juice beverages. Therefore, this study aimed to develop and evaluate a functional peach juice enriched with protein–β-glucan nanoparticles and to investigate their effects on physicochemical stability, gastrointestinal behavior, metabolic enzyme inhibition, antioxidant retention, and sensory acceptance. Protein–β-glucan nanoparticles produced from Fusarium venenatum protein isolate and Fuscoporia torulosa β-glucans were incorporated into peach juice formulations (V1–V4) and characterized using dynamic light scattering, zeta potential analysis, transmission electron microscopy (TEM), and Fourier-transform infrared spectroscopy (FTIR). In vitro gastrointestinal digestion was performed to assess β-glucan bioaccessibility, protein digestibility, antioxidant activity, and release kinetics, while α-amylase and α-glucosidase inhibition assays, sensory evaluation, digital sensory analysis, principal component analysis (PCA), and exploratory multivariate analysis were used to evaluate relationships among formulation characteristics and functional performance. The nanoparticles formed stable colloidal systems with mean particle sizes ranging from 176 to 229 nm and maintained structural integrity during 28 days of refrigerated storage. Nanoparticle-enriched formulations exhibited higher β-glucan bioaccessibility, improved antioxidant retention, and stronger α-amylase and α-glucosidase inhibitory activities, with the greatest effects observed in V4. Protein digestibility remained high across all formulations, while sensory evaluation revealed improved overall liking and purchase intention. PCA indicated that nanoparticle concentration was the main factor differentiating the formulations based on their physicochemical and functional characteristics. Overall, protein–β-glucan nanoparticles enhanced the physicochemical, functional, and sensory properties of peach juice, supporting their application as multifunctional ingredients for functional beverage development.

Characterization of Sago Starch Complex with Ferulic Acid Isolated from Corn Cob and Evaluation of Antioxidant Activity

ABSTRACT. Corncob is one of agro-food by-products, a potential source of natural antioxidants and functional food ingredients, rich in ferulic acid and dietary fibre. In this study, ferulic acid was isolated from corncobs after alkaline pretreatment using a multi-step extraction process and structurally verified, providing a suitable bioactive compound for baruk sago (SB) starch complexation. FTIR analysis showed characteristic absorption peaks at 3379-3387 cm⁻¹, indicating interactions between FA and starch. XRD results revealed a transformation of the native SB starch crystalline structure and a marked decrease in crystallinity from 40.31% to 8.60% after complexation. SEM observations demonstrated morphological changes from predominantly smooth, oval, and compact granules to a looser gel structure in the starch–FA complex. In vitro antioxidant evaluation using the DPPH radical scavenging assay showed that the SB starch–FA complex exhibited higher scavenging activity compared to native SB and pre-gelatinized (SBG) starch. These findings confirm the successful incorporation of FA into SB starch and demonstrate that complexation significantly modifies physicochemical properties and enhances antioxidant capacity, highlighting its potential application as a functional food ingredient and nutraceutical material.   Keywords: Antioxidant, characterization, sagu baruk, starch-ferulic acid complex

Comparative Effects of Soybean Protein Isolate- and Myofibrillar Protein-Based Curcumin Nanocomplexes on the Freeze-Thaw Stability of Surimi.

Proteins are effective carriers for polyphenols, yet whether structural differences between plant- and animal-derived proteins influence the delivery and functionality of polyphenols in their nanocomplexes remains unclear. In this study, soy protein isolate-curcumin (SPI-CUR) and myofibrillar protein-curcumin (MP-CUR) nanocomplexes were fabricated via a pH-driven method, and their physicochemical properties, interaction mechanisms, and cryoprotective effects on surimi were investigated. Both nanocomplexes achieved high encapsulation efficiencies (90.63% for SPI-CUR and 83.29% for MP-CUR) and thus exhibited enhanced antioxidant activity. CUR loading induced conformational changes in the protein carriers, as evidenced by increased α-helix content and decreased β-sheet content, suggesting the formation of a more compact structure. Meanwhile, this conformational change was accompanied by a marked reduction in particle size, with SPI-CUR reaching 66.13 nm. Molecular docking further revealed that hydrophobic interactions and hydrogen bonding were the primary forces stabilizing both nanocomplexes. During freeze-thaw cycles of surimi, both SC and MC nanocomplexes were superior to commercial cryoprotectants in preserving product quality, evidenced by improved water-holding capacity, enhanced gel properties, and inhibited protein oxidation. Notably, the two nanocomplexes exhibited distinct protective profiles depending on the protein source. MP-CUR demonstrated superior preservation of gel texture by minimizing thawing loss to 0.53% and maintaining high hardness (425.50 ± 34.85 g) and springiness (0.81 ± 0.03), which facilitated the formation of a denser gel network. In contrast, SPI-CUR demonstrated superior viscoelasticity and yielded the highest storage modulus (G'). This study establishes a foundation for the rational design of natural and efficient surimi cryoprotectants derived from protein-polyphenol complexes.

Biosynthesis and functionalization of recombinant bovine lactoferrin: Alginate-mediated stabilization and MTGase-induced gelation for anthocyanin delivery.

Bovine lactoferrin (BLF) is a milk-derived glycoprotein with diverse biological activities, including antimicrobial, antioxidant, and immunomodulatory functions, with potential for applications in functional foods and nutraceuticals. However, its practical utilization remains limited by key challenges: low efficiency of traditional extraction methods, poor gastrointestinal stability, and a narrow range of application forms. To address these issues, this study developed an integrated strategy spanning from efficient production to functional application. First, the Pichia pastoris expression system was optimized through signal peptide engineering and chaperone co-expression, achieving high-yield secretory production of recombinant BLF (rBLF) at 232.6 mg/L in shake-flask fermentation. Subsequently, rBLF was complexed with sodium alginate (NaAlg) via electrostatic self-assembly to form nanocomposites for gastrointestinal protection. The rBLF-NaAlg complex exhibited remarkable resistance to simulated gastric digestion, with only a 23.7% reduction in particle size, significantly lower than the 71.1% reduction observed for free rBLF. Furthermore, a three-dimensional hydrogel delivery system was constructed through microbial transglutaminase (MTGase)-catalyzed cross-linking. This system demonstrated encapsulation and sustained release of anthocyanins as a model bioactive compound. The gel structure and performance showed a clear enzyme concentration dependence: moderate cross-linking (<80 U/g) resulted in a uniform and dense network, enhancing encapsulation efficiency and providing controlled release. This work establishes a complete technological pathway from high-yield production and stabilization to functional expansion, demonstrating that rBLF can be transformed from a labile bioactive protein into a dual-functional material with both nutritional and delivery capabilities. This integrated strategy provides a viable solution for developing advanced BLF-based functional foods and nutraceutical delivery systems.

Optimization, Characterization, and Application of Soy Protein Isolate–Catechin Composite Microspheres in Emulsified Beef Balls

Rice Bran-Enriched Food Model with Reduced Glucose Bioaccessibility, Bioavailability and Enhanced Cellular Antioxidant Potential

Incorporation of byproducts into food systems and research on their potential bioactivity has a considerable impact on circular food systems. This study evaluates physicochemical and functional properties of rice bran as an ingredient in a food model. Rice starch was replaced partially with rice bran at different levels (20%, 40% and 60%) in a pudding-like food model, increasing compositional diversity and structural heterogeneity. Rice bran significantly changed colour and textural properties such as hardness, adhesiveness, gumminess, and chewiness (P<0.05). Rice bran incorporation reduced glucose release during in vitro digestion and subsequently bioavailable glucose in the bicameral CaCo-2 transport system (P<0.05). The bioactive γ-oryzanol was released during in vitro digestion, with levels of 116.31±0.78 and 71.00±4.33 μg/mg of sample for the 40% and 60% replacements, respectively. Also, rice bran recovered cell viability in an oxidatively challenged in vitro system at 40% replacement. Overall, rice bran enriched the composition and structure, altered texture, lowered glucose accessibility and availability, and enhanced antioxidant potential.