Sensory Influence of Sweetener Addition on Traditional and Decaffeinated Espresso

Several factors have led to an increase in the consumption of sweeteners in substitution of sucrose. Studies on the behavior and the sensory properties of sweeteners are relevant, once they provide knowledge about both the adequate sweetener concentration with a sweetness equivalence to a sucrose-sweetened product and the possible sensory changes of the product. The addition of stevia with different rebaudioside A concentrations and sucralose to traditional and decaffeinated espresso coffee was studied, using the just-about-right scale and magnitude estimation method, to determine the ideal sweetness and the acceptance of the samples. The effect of the intensity of sensory attributes sweet taste, bitter taste, coffee flavor, and body in the acceptance was evaluated by penalty analysis. Decaffeinated presented proportionally lower sucrose concentration and sweetness equivalence than the traditional samples. Stevia concentrations were similar, despite the different rebaudioside A concentrations, for both traditional and decaffeinated samples, and rebaudioside A levels from stevia in espresso have no differences in sweetness intensity. Sucralose was the most intense sweetener in espresso. Although no differences were observed in the acceptance test in relation to appearance, aroma, and texture among the samples, the internal preference map showed segmentation of consumers with respect to the acceptability. This segmentation is more related to the type of sample than the added sweetener. Penalty analysis demonstrated that the most penalizing sensory characteristics were "coffee flavor" and "sweet," leading to a significant decrease in the acceptability of the samples. PRACTICAL APPLICATION: Conclusions obtained are important source of knowledge for the coffee industry, in the development and manufacture of beverages with coffee. The present findings can help to understand the behavior and the sensory properties of sweeteners. They provide knowledge about sensory perception of sweet and bitter tastes, and the factors that influence this perception and the sensory profile of the samples, once the behavior of sweeteners varies according to the product to which they are added.

Perception of Bitter Taste through Time-Intensity Measurements as Influenced by Taste Modulation Compounds in Steviol Glycoside Sweetened Beverages

To limit sugar consumption and maintain sweetness levels in the diet, food and beverage developers often use high potency sweeteners (HPSs) as alternatives. Steviol glycosides are considered a consumer-friendly alternative but they are perceived to have a bitter taste accompanied by sweet and bitter lingering. Recently, taste modulators have been discovered that help to alleviate negative attributes like bitterness of HPSs. To show that taste modulation compounds (TMCs) decrease perceived bitterness associated with steviol glycosides, a trained descriptive panel (n = 9) performed a single-attribute time-intensity (TI) assessment over 2 min. Analysis of Variance (ANOVA) was used to analyze TI curves and curve parameters (AUC, Imax and Tmax). Principal components analysis (PCA) was also used to assess TI curves. Results showed that statistically significant results depended on the analysis method. Bitterness perception was shown to persist less over 2 min for steviol glycosides with TMCs when assessing raw scores and parameters. The same was not found using differences from control curves or weighted curves from PCA. These findings demonstrate that particular TMCs may subtly decrease perceived bitterness of steviol glycosides. However, business objectives of TMC use may dictate what kind of analysis method to use when analyzing perceived bitter perception of TMCs over time.