Feng Yaping, Qiao Bingqian, Lu Xue, Xiao Jianhui, Yu Lili, Niu Liya
School of Food Science and Engineering, Jiangxi Agricultural University, 1101 Zhimin Road, Nanchang 330045, China.
Foods. 2024 Mar 10;13(6):843. doi: 10.3390/foods13060843.
Anthocyanins are prone to degradation and color fading after sterilization. This work examined the potential of wheat protein hydrolysates (WPHs, 40 g/L) in improving the stability of purple sweet potato anthocyanins (PSPAs) under a pH of 6.8 after sterilization at 121 °C followed by storage. Results showed that WPHs increased the thermal degradation half-life of PSPAs 1.65 times after sterilization. Compared to PSPAs alone, after being stored at 37 °C and 45 °C for 7 days, the retention concentration of PSPAs with WPHs was 5.4 and 32.2 times higher, and the color change of PSPAs with WPHs decreased from 6.19 and 10.46 to 0.29 and 0.77, respectively. AFM data, fluorescence and UV spectrograms indicated the formation of complexes between PSPAs and WPHs by hydrophobic attraction confirmed by zeta-potential data. PSPAs with WPHs had stable particle size and zeta potential, which may also significantly increase the concentrations after digestion and antioxidant power of PSPAs. This work indicated that the assembled PSPAs composite structure by WPHs significantly reduced the degradation of PSPAs at a pH of 6.8 after sterilization at 121 °C followed by long-term storage.
花青素在灭菌后容易降解和褪色。本研究考察了小麦蛋白水解物（WPHs，40 g/L）在121℃灭菌并储存后，于pH 6.8条件下提高紫薯花青素（PSPAs）稳定性的潜力。结果表明，WPHs使灭菌后PSPAs的热降解半衰期提高了1.65倍。与单独的PSPAs相比，在37℃和45℃储存7天后，添加WPHs的PSPAs的保留浓度分别高出5.4倍和32.2倍，添加WPHs的PSPAs的颜色变化分别从6.19和10.46降至0.29和0.77。原子力显微镜数据、荧光和紫外光谱图表明，PSPAs与WPHs之间通过疏水作用形成了复合物，zeta电位数据证实了这一点。添加WPHs的PSPAs具有稳定的粒径和zeta电位，这也可能显著提高PSPAs消化后的浓度和抗氧化能力。本研究表明，在121℃灭菌并长期储存后，由WPHs组装的PSPAs复合结构在pH 6.8时显著降低了PSPAs的降解。
