Instrumental and Sensory Texture Evaluation of Semisweet Chocolate Bars Added with Different Plant Extracts

Abstract

Sensory perception is extremely important both in academic research and in the food industry, for the generation of knowledge applied to the development and innovation of products. The textural characteristics of chocolate define acceptance and its durability. The evaluation of instrumental and sensory characteristics is very important to the research and development of chocolate bars. The objective of this work is to analyze the instrumental texture and sensory acceptance in relation to the texture and overall impression of bitter chocolate bars produced with different plant extracts (acai, cinnamon, guarana, hibiscus, jambu and mate) and to verify the existence of relationships between instrumental texture and acceptance of bitter chocolate bars. Seven chocolate formulations were prepared, one standard and six containing each one of the different plant extracts mentioned before (one formulation for each extract). To determine the breaking strength of the chocolate bars, measuring 8.0 x 2.5 x 1.0 cm, respectively, length, width and height, a texturometer TA.XT2i, Stable Micro System, based on SMS P/W and probe HDP/3PB, with ten replicates per sample. The test speed programmed in the equipment was 4.0 mm/s. The results of the instrumental texture of the chocolates ranged from 9.44 to 10.79 kgf/cm for the standard and chocolate with hibiscus extract, respectively. The acceptance of the samples was carried out in relation to texture and the global impression by 150 bitter chocolate consumers, recording their scores on a 9-point hedonic scale. According to the regression analysis, there was no significant linear correlation between instrumental texture and acceptance in relation to texture and overall impression (p>0.05). This result highlights the importance of sensory acceptance, especially to new product development, because there is not always a significant linear correlation between sensory and instrumental results that could present predictive results.