The Sweet Characteristics Of Stevioside And Its Applications In Food

Stevioside is a natural, low-calorie, non-nutritive, high-intensity sweetener, and it is not broken down for energy in the body and has no toxicity. The safety of stevioside has been approved by FAO and WHO. Stevioside has been approved using as a natural sweetener since 1985 by china's ministry of health. The application of stevioside in food is still in the initial stage because of the bitter and astringent aftertastes. The sweet characteristics of stevioside and its applications in iced black tea and yogurt were studied in the paper. The research could provide theoretical guidance for the applications of stevioside in food to develop low-calorie and low-sugar foods.The sweet characteristics of Stevia were studied. The measurements of the relative sweetness of the stevioside were accomplished using the method of magnitude estimation. And the flavor profiles of Stevia were evaluated by quantitative descriptive analysis (QDA). The results showed that Stevia was 206 times sweeter than 2% equi-sweet sucrose while it was 140 times sweeter than 5% equi-sweet sucrose. The sweetness potency of Stevia had a down trend with the concentration of Stevia increasing. The bitterness, astringent and metallic tastes were significantly different from those of sucrose. The remaining attributes of Stevia were close to sucrose. The most prominent bad taste of Stevia was bitter.The effect of Stevia on the quality of iced black tea with Stevia substituting for sucrose was studied. The iced black tea with different ratios of Stevia and sucrose was evaluated by hedonic ranking sensory method. The results demonstrated that 0.462 g/L stevioside may replace 60 g/L sucrose in iced black tea, with a 67% decrease in calories, without affecting the sensory characteristics of the product. It is not significantly different in terms of desirability from the commercial iced black tea.The effects of Stevia on its qualities applying in set yogurt replacing sucrose were studied. The physical and chemical properties of set yogurt with different ratios of Stevia and sucrose were analyzed. The yogurt was evaluated by 9-point hedonic scale method. The results indicated that the acidity and lactic acid bacteria counts of yogurt had a downward trend with the amounts of stevia increasing, but the overall downward trend was not obvious. Still the acidity and lactic acid bacteria counts of yogurt reached the national standards. There were not significant differences among the yogurt with Stevia and sample with sucrose only on the hardness, adhesiveness, springiness and cohesiveness by texture profile analysis (TPA). The viscosity, water holding capacity (WHC) and susceptible to syneresis (STS) were decreased with the amounts of Stevia increasing, while they were not significantly different. The titratable acidity of yogurts changed slowly with the amounts of stevioside increasing during the storage, and then Stevia could make the acidity of yogurt change slowly. 0.28 g/L Stevia could replace 18 g/L sucrose in yogurt without affecting the texture and sensory qualities of yogurt.