Valdecir Luccas

Bittersweet chocolates containing prebiotic and sweetened with stevia (Stevia rebaudiana Bertoni) with different Rebaudioside A contents: multiple time–intensity analysis and physicochemical characteristics

Summary The objective of this study was to evaluate the time–intensity profile of the sensory attributes possibly affected in sugar-free and low-fat chocolates containing inulin and stevia with different rebaudioside A contents, such as sweetness, bitterness and melting rate. The bittersweet chocolates were analysed by the multiple time–intensity analysis. The time–intensity profile for the sweetness stimulus was similar for all chocolate samples. The differences between the contents of rebaudioside A were not perceived by the assessors. In relation to the bitterness stimulus, the low-fat samples had a more accentuated perception of this attribute by the assessors, with significant differences for Imax and Area when compared to the sugar-free samples. The stimulus melting in the mouth was more affected in the low-fat samples. The sensory results obtained in this study are useful for food industry and researchers working with sweeteners and prebiotics in food, especially in chocolates.

The Influence of the Rebaudioside A Content of Stevia (Stevia rebaudiana Bertoni) on the Determination of Sweetness Equivalence in Bittersweet Chocolates, Using the Time‐Intensity Analysis

The consumption of diet products has increased greatly in recent years. The objectives of the study were to develop a bittersweet chocolate added inulin and stevias with different rebaudioside A contents (60%, 80%, and 97%). Five chocolate samples were formulated with different sucrose concentrations to determine the ideal sucrose concentration for bittersweet chocolate. The use of just-about-right scale identified an ideal sucrose concentration of 47.5% (w/w). The sweetness equivalence in sugar-free bittersweet chocolates was determined by the time-intensity method by 14 selected and trained judges. The data collected during each session of sensory evaluation furnished the following parameters in relation to the sweet stimulus: Imax (maximum intensity recorded), Timax (time at which the maximum intensity was recorded), Area (area of time × intensity curve), and Ttot (total duration time of the stimulus). The time-intensity analysis indicated that the percentages of rebaudioside A did not interfere with the sweetness intensity of the sweetener stevia in bittersweet chocolate and there was no significant difference in the concentrations tested (0.16%, 0.22%, 0.27%) of each stevia, in relation to the parameters evaluated. In addition, the reduction in fat content did not alter the perception of the sweetness intensity of the samples. These results showed important information to research and development of chocolate products. Therefore, the use of the lowest stevia concentration tested (0.16%) is the most indicated for use, since this quantity was sufficient to reach the ideal sweetness of the product, so there was no point in adding more.

AVALIAÇÃO DE PROPRIEDADES TÉRMICAS DE MANTEIGA DE CACAU E GORDURAS ALTERNATIVAS

As recentes mudancas na Legislacao Brasileira para chocolates abriram novas perspectivas para os fabricantes de gorduras e chocolates, ja que permite a substituicao parcial da manteiga de cacau por gorduras alternativas. Este trabalho teve como objetivo avaliar as propriedades termicas (temperatura de fusao e entalpia) de amostras cristalizadas de manteiga de cacau com gorduras alternativas para futuras aplicacoes em chocolates. Os resultados mostraram que o maior decrescimo no ponto de fusao das misturas ocorreu a partir da incorporacao de 10% de cupuacu ou CBR na manteiga de cacau. Ja para as misturas com gordura CBS, a diminuicao no seu ponto de fusao e evidente desde 5% de CBS na manteiga de cacau. A metodologia para determinacao do ponto de fusao via DSC se mostrou mais precisa do que a metodologia via RMN. O valor de entalpia da manteiga de cacau pura foi de 92,7 J/g.