六偏磷酸钠对黄碱性面条酶促褐变的抑制机理。

Inhibitory mechanism of sodium hexametaphosphate on enzymatic browning in yellow alkaline noodles.

机构信息

State Key Laboratory of Food Science and Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi 214122, Jiangsu Province, PR China; School of Food Science and Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi 214122, Jiangsu Province, PR China.

出版信息

Food Chem. 2023 Jun 30;412:135533. doi: 10.1016/j.foodchem.2023.135533. Epub 2023 Jan 21.

DOI:10.1016/j.foodchem.2023.135533

PMID:36716630

Abstract

The effect and mechanism of sodium hexametaphosphate (SHMP) on polyphenol oxidase (PPO) enzymatic browning in yellow alkaline noodles (YAN) were investigated. The browning degree and PPO activity in YAN or PPO solutions decreased with the SHMP concentrations increased. Variations in pH values (pH 7-8.5) adjusted by HCl or acetic acid slightly affected the PPO activity, but SHMP inhibited PPO activity more pronounced. The inhibition of SHMP on PPO activity was irreversible. SHMP formed coordinate covalent bonds with Cu to make PPO inactive. HPLC analysis revealed that SHMP reduced the browning products and led to the color of PPO-catechol systems being lightened. Furthermore, SHMP inhibited browning by hampering the auto-oxidization of intermediate products due to the change in pH value. Besides, the HPLC chromatogram, UV-vis spectrum, and mass spectrometry revealed that SHMP could convert melanin (m/z 248.97, 723.5, and 836.58) to light-colored substances (m/z 137.11).

摘要

研究了六偏磷酸钠（SHMP）对黄碱性面条（YAN）中多酚氧化酶（PPO）酶促褐变的影响及作用机制。随着 SHMP 浓度的增加，YAN 或 PPO 溶液的褐变程度和 PPO 活性降低。通过 HCl 或乙酸调节的 pH 值（pH 7-8.5）的变化对 PPO 活性的影响较小，但 SHMP 对 PPO 活性的抑制作用更为明显。SHMP 对 PPO 活性的抑制作用是不可逆的。SHMP 与 Cu 形成配位共价键，使 PPO 失活。HPLC 分析表明，SHMP 减少了褐变产物，使 PPO-儿茶酚体系的颜色变浅。此外，由于 pH 值的变化，SHMP 通过阻碍中间产物的自动氧化来抑制褐变。此外，HPLC 色谱图、紫外-可见光谱和质谱表明，SHMP 可以将黑色素（m/z 248.97、723.5 和 836.58）转化为浅色物质（m/z 137.11）。