The present invention addresses the problem of providing a simple and versatile method for stabilizing 2-O-[alpha]-D-glucosyl-L-ascorbic acid in an acidic aqueous medium. The problem is solved by providing a method for stabilizing 2-O-[alpha]-D-glucosyl-L-ascorbic acid in an acidic aqueous medium, said method characterized in that 2-O-[alpha]-D-glucosyl-L-ascorbic acid is made to coexist with one or more stabilizers selected from C4-6 sugar alcohols, glucosyl fructose and sugar alcohols thereof, sugar alcohols of gluco-trisaccharides, glycosyl-trehalose, derivatives of cinnamic acid, derivatives of gallic acid and catechin, tartaric acid and salts thereof, amino acids, and peptides.本發明為提供一種在酸性水系媒體中之2-O-α-D-糖基-L-抗壞血酸的簡便且具有廣泛使用性之安定化方法作為課題。本發明藉由提供一種在酸性水系媒體中之2-O-α-D-糖基-L-抗壞血酸的安定化方法而解決上述課題，其特徵為使2-O-α-D-糖基-L-抗壞血酸與選自碳數4至6的糖醇、糖基果糖或其糖醇、葡萄糖三糖的糖醇、糖基海藻糖、桂皮酸衍生物、兒茶素或没食子酸衍生物、酒石酸或其鹽、及胺基酸或肽的1種或2種以上之安定化劑共存者。
