Regulating effect of glycated rice bran protein aggregates and resultant emulsions on the gelatinization and retrogradation properties of rice starch

• Published in: Food hydrocolloids 2025-03, Vol.160, p.110785, Article 110785
• Main Authors: Luo, Yongxue, Cui, Hanwen, Tang, Wenting, Fu, Zeyue, Pu, Chuanfen, Sun, Qingjie
• Format: Article
• Language: English
• Subjects: calorimetry; crystal structure; electron microscopy; Emulsions; enthalpy; gelatinization; gels; hardness; hydrocolloids; hydrogen; nutrition; Protein aggregates; Retrogradation; rheology; rice bran; Rice starch; starch; storage modulus; storage time; viscosity; X-ray diffraction
• ISSN: 0268-005X
• DOI: 10.1016/j.foodhyd.2024.110785

The effects of the rice bran protein aggregates (RBPAs), glycated rice bran protein aggregates (gRBPAs) and resultant emulsions on the gelatinization and retrogradation characteristics of rice starch (RS) were investigated. The gelatinization and retrogradation properties of RS were determined by rapid viscosity analyzer (RVA), differential scanning calorimetry (DSC), dynamic rheology, X-ray diffraction (XRD) and scanning electron microscopy (SEM). The addition of the protein aggregates and the emulsions reduced the swelling of starch during the gelatinization process and the enthalpy change (ΔH) of RS. Meanwhile, during the long-term storage (4 °C for 21 d), the existence of the protein aggregates and the emulsions decreased the storage modulus (G′) and hardness of RS gel, thereby decelerating the retrogradation of RS. Besides, XRD analysis proved that when heated for 2 h, the relative crystallinity of the RS-gRBPAs mixture decreased by 6.08%, and the relative crystallinity of the corresponding RS-emulsions mixture reduced by 6.85%, which indicated the grafting of Dex could impede the retrogradation of RS. The inhibitory effect of adding the emulsions was more pronounced than that of adding corresponding protein aggregates. Furthermore, SEM analysis confirmed that the gel network structures of mixture were more uniform and compact compared with RS, which resulted from the protein aggregates and the emulsions inhibiting the internal combination through hydrogen bonds between starch molecules. Overall, these findings suggested that the protein aggregates and the emulsions prevented the retrogradation of RS, and could be potently used as a natural substitutes to enhance the quality and nutrition of starch-based foods. [Display omitted] •The protein aggregates and emulsions inhibited the gelatinization of rice starch (RS).•The glycated protein aggregates and emulsions retarded the retrogradation of RS.•The grafting of dextran (Dex) delayed the retrogradation of RS through hydrogen bonds.•The hardness of RS gel was reduced by adding the protein aggregates and the emulsions.•The anti-retrogradation effect of emulsions was more obvious than protein aggregates.