Metodologia Napping® para a otimização: um estudo de caso na avaliação de um mix de diferentes stévias em iogurte

Abstract

It is clear that consumers are concerned with their health and esthetics. Thus, they are more attentive their diet. Faced with this trend, arises the need to offer natural healthier produtcs, replacing sucrose and artificial sweeteners by natural sweeteners, without compromissing the product’s sensorial quality. A manner to overcome the individual limitations of natural sweeteners is to use then as a mix. However, formulations optimization generally need trained panelists and numerous sessions, being an expensive and prolonged task. Therefore, this work proposes the use of the Napping methodology®, a fast descriptive sensorial analysis, associated with the mixture rule, to optimize a mix of stevias, aiming to replace sucrose and sucralose in protein rich yogurts. Three different natural stevia-based sweeteners were used: 75% of Stevioside + Rebaudioside A (S1); 95% of Rebaudioside A (S2); and 50% of Rebaudioside A (S3). First, a Just-About-Right test was conducted to evaluate the ideal of sweetness in proteic yogurts. Then, 12 formulations were prepared, such that they provide the same ideal of sweetness. The 10 first formulations were developed through the mixture rule, employing the three studied stevias. The other formulations were sucrose and sucralose, respectively. Napping® evaluated these 12 formulations to develop an optimized mix of stevias for protein rich yogurts taking into account the Euclidian distance between the formulations sweetened with stevia and the formulations with sucrose and sucralose. The optimized mix was composed by 55% of S1, 5% of S2 and 40% of S3. The efficience of the optimized formulation was evaluated by the Temporal Dominance of Sensations analysis and an acceptance test, comparing it with yogurts sweetened with sucrose and sucralose. The sensory profile of the optimized formulation was very similar to the other sensory profiles, being the sweet taste predominant during most of the analysis’ time. Besides, no undesirable residual taste was perceived. Moreover, no significant difference (p ≥ 0,05) between the formulations was perceived in the acceptance test. Therefore, we can affirm that the proposed methodology was efficient to develop a diet yogurt formulation, using a mix of different stevias, besides being interesting to the food industry, because it is a fast, easy and efficient methodology for formulations optimization.