The effects of β-lactoglobulin on cyanidin-3-O-glucoside antioxidant activity and bioaccessibility after heat treatment

• Published in: Food research international Vol. 157; p. 111494
• Main Authors: Qie, Xuejiao, Chen, Wenpu, Wu, Renyi, Wang, Zhaojun, Zeng, Maomao, Chen, Jie, Douglas Goff, H., He, Zhiyong
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.07.2022
• Subjects: Antioxidant activity; Bioaccessibility; Cyanidin-3-O-glucoside; Heat treatment; Interaction; β-Lactoglobulin; Bioaccessibility; Heat treatment; β-Lactoglobulin; Interaction; Antioxidant activity; Cyanidin-3-O-glucoside
• ISSN: 0963-9969; 1873-7145
• DOI: 10.1016/j.foodres.2022.111494

[Display omitted] •Thermal treatment and the addition of C3G changed the secondary structure of β-Lg.•No β-Lg-C3G covalent complexes formed after thermal treatment at 25–121 °C.•β-lg addition was effective in maintaining the color of C3G after thermal treatment.•Hydrophobic interaction between β-Lg-C3G enhanced the FRAP and bioaccessibility of C3G.•Protective effect of β-lg on C3G above 85 °C was stronger than that at 25 °C and 60 °C. The impact of heat treatment at different temperatures on the interaction of β-lactoglobulin (β-Lg) and anthocyanin-3-O-glucoside (C3G) was studied. Heat treatment and the addition of C3G changed the secondary structure of β-Lg with decreasing β-sheets and increasing random coils. Interactions between C3G and β-Lg were mainly via hydrogen bonds and van der Waals forces at 25 °C. The elevated temperature promoted hydrophobic interactions between C3G and β-Lg due to an increase in the hydrophobic groups and amino groups on the surface of β-Lg molecules. The addition of β-Lg to the C3G eliminated heat-induced thermal degradation of C3G. The β-Lg–C3G interactions accompanied with increased particle size and constant zeta potential could increase the antioxidant capacity of C3G approximately by 4% to 10% and protect the colour of C3G from degradation under heat treatment. The C3G bioaccessibility with β-Lg addition increased by 26.08%, 33.45%, 83.09%, 72.27%, and 354.62% compared with C-25, C-60, C-85, C-100, and C-121, respectively. The protective effect of the non-covalent interactions on C3G at high temperatures (85 °C to 121 °C) was significantly stronger than at 25 °C and 60 °C. The application of β-Lg in foodstuffs could enhance the antioxidant activity and bioaccessibility of C3G.