Synthesis and characterization of glucosyl stevioside using Leuconostoc dextransucrase

•Glucosyl stevioside (GS) was synthesized by dextransucrase with 94% production yield.•GS showed 2-fold improve quality of taste and sweetener compared to stevioside.•GS had high solubility, 98%, in aqueous solution.•GS exhibited high stability in commercial available soft drinks.•GS could apply novel sweetener with high yield and stability. Glucosyl stevioside was synthesized via transglucosylation by dextransucrase from Leuconostoc citreum KM20 (LcDexT), forming α-d-glucosyl stevioside. A production yield of 94% was reached after 5days of LcDexT reaction at 30°C. Glucosyl stevioside induced a 2-fold improved quality of taste and sweetness, compared to stevioside. After 15days of storage at 25°C, 98% of glucosyl stevioside in an aqueous solution was present in a soluble form, compared to only 11% for stevioside or rebaudioside A. Furthermore, glucosyl stevioside exhibited a similar or improved stability in commercially available soft drinks, when compared to stevioside and rebaudioside A. These results suggest that glucosyl stevioside could serve as a highly pure and stable sweetener in soft drinks.