Sweetness Concentration-Response Behavior of Rebiana at Room and Refrigerator Temperatures

Rebiana is a zero-calorie, natural, high-potency sweetener derived from Stevia rebaudiana Bertoni and comprising almost pure rebaudioside A. Reliable information on its sweetness concentration-response (C-R) behavior is fundamental to rebiana's use as an ingredient. The response curve of rebiana in room-temperature (21 degrees C) and refrigerated (5 degrees C) water was determined using 2-alternative forced choice discrimination tests with a minimum of 70 tasters. From a series of panels the proportion of tasters finding different sucrose concentrations sweeter than a fixed concentration of rebiana was plotted against sucrose concentration. The resultant sigmoid curves were linearized by transforming the ordinate axis to a probability scale. This aided experimental design and determination of isosweet concentrations. The latter were deemed to be the sucrose concentration at which 50% of tasters found it to be the sweeter of the pair. Isosweet concentrations of sucrose for seven rebiana concentrations up to 600 mg/L were used to construct a C-R curve for each temperature. Equations were derived for the resultant hyperbolic curves. Rebiana is significantly more potent in cold water.