Applicability of electromyography (EMG) as a prospective technique for textural evaluation of different types of biscuits

Bakery industry is an important segment of the food industry, worldwide, and texture is an important determinant in the consumer acceptability of baked products especially biscuits. In this study, six different textured biscuits namely, whole wheat flour biscuit, chocolate biscuit, cumin biscuit, cardamom biscuit, pistachio biscuit and cashew biscuit, procured from local bakery, were analyzed for their proximate composition and color characteristics. The biscuits were having significantly (p ≤ 0.05) different values for proximate composition and color parameters. This study primarily aimed at investigating the application of electromyography (EMG) as a prospective technique for texture evaluation of these different types of biscuits. EMG is an upcoming technique for in vivo food texture evaluation which gives real-time information about the dynamic textural changes occurring during mastication of a food product. The EMG study was conducted on ten human subjects who were served six samples of biscuits in duplicate. To eliminate subject factor variance, two-way ANOVA was applied on the relative values of EMG variables. Two recordings of same subject in an EMG session for a biscuit sample showed significant (p ≤ 0.05) degree of similarity indicating that human mastication behavior is reproducible. Initially, twenty-eight EMG parameters were obtained which were reduced to five representative parameters using cluster analysis. Principal component analysis further classified these five masticatory parameters into two independent principal components (PC1 and PC2) for explaining the data variance. Cumulative proportions for PC1 and PC2 were 37.6% and 70.8%, respectively. The results showed that mastication time obtained from electromyographic analysis can evaluate sensory fracturability, hardness and chewiness. While middle interburst duration can effectively evaluate sensory cohesiveness and instrumental flexural strength. The study concluded that EMG can serve as a comprehensive texture evaluation tool in the bakery industry.