Impact of pivot selection and lexicon utilization on pivot profile analysis of food off-odor reduction: The case of soymilk

The presence of unpleasant odors in many foods (especially food ingredients) impedes their development and production, and the application of lactic acid bacteria fermentation may help alleviate these undesirable odors. As a rapid pivot-based descriptive analysis methodology, the Pivot Profile (PP) has shown promise for evaluating foods with reduced off-odor. This study aimed to identify the optimal pivot for analyzing sensory off-odor reduction samples by manipulating a pivot using fermented soymilk as a sample, examining the impact of utilizing a lexicon on PP results with an untrained panel (UP), and comparing its performance with that of a semi-trained panel (SP) using the PP methodology. The study involved three rounds of PP, each round PP comprising two independent PP, with unfermented soymilk and a within-set fermented soymilk serving as pivots, respectively. The UP conducted a PP round with free descriptions, followed by a discussion on creating a descriptor lexicon and then another PP round. Subsequently, the SP (12 h of training) conducted a round of PP. The results showed that SP-PP was most similar to the descriptive analysis (DA) conducted by the trained panel (TP, 33 h of training) in describing the samples. In the PP conducted by UP, the results of PP with free descriptions were more similar to that of TP-DA compared to PP with a lexicon. Overall results suggest using a within-set sample as a pivot is more appropriate for evaluating off-odor reduction samples, and conducting PP with lexicon-trained SP may lead to more precise results.