agent of protective coloration护色剂
it was a protective coloration这是保护性染色
Both browning AND protective coloration of the balsam pear juice were in some detail looked into ,then we ascertained zinc gluconate AND calcium hydroxide for color fixative and effectively kept balsam pear raw material proper green.
实验对苦瓜汁的褐变和护色稳定性等关键因素进行了较详细地研究和探讨，确定葡萄酸锌和氢氧化钙为护色剂，有效地保持了苦瓜原料特有的绿色。
参考来源 - 苦瓜汁饮料及其相关性因素的研究N（名词） the coloration of an animal that enables it to blend with its surroundings and therefore escape the attention of predators 保护色