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The effects of different fermentation strains on the flavor characteristics of fermented soybean curd (FSC) were investigated in this study. Fresh tofu was fermented by Actinomucor elegans, Rhizopus arrhizus, Mucor racemosus, and Rhizopus chinensis, either alone or in various combinations. The FSC manufacturing process included prefermentation by different strains at 28 °C for 60 hr, followed by salting at 16 °C for 7 days and finally proceeding postfermentation at 25 °C for 35 days. Subsequently, five tested samples were obtained, namely, sample A (fermented by A. elegans alone), R (fermented by R. arrhizus alone), AR (fermented by A. elegans and R. arrhizus at 5:1), AM (fermented by A. elegans and M. racemosus at 1:1), and RR (fermented by R. arrhizus and R. chinensis at 7:3). The flavors of the five samples were determined by E‐nose, sensory evaluation, and GC‐MS. E‐nose system observed significant discriminations by principal component analysis and linear discriminant analysis analysis. Sensory evaluation ranked the overall sensory scores: AR>AM>A>RR>R. As shown in GC‐MS results, sample AR also had, on average, the highest level of many volatiles. Out of 10 critical volatiles, the detected frequency of samples AR, AM, RR, A, and R was 10, 9, 9, 8, and 7, respectively. PLS2 regression model was used to explore the influence on flavor quality of different strains. All three analytic methods revealed similar results, with sample AR providing the best flavor quality, while the opposite was the case with sample R. Therefore, it could be concluded that A. elegans and R. arrhizus at 5:1 (v/v) was the optimal combination, and may likely promote the production of critical volatile compounds. Practical Application The flavors of fermented soybean curds are influenced by various factors such as physicochemical and microorganism during the fermentation surroundings. The results of this work not only provide valuable information for FSC flavor studies, but can also guide the FSC industry to improve flavor quality by applying the most appropriate production strains.

The present study was designed to investigate the consumer preference and the quality attributes of five brands of Chinese traditional first-grade fava pastes, following which their quality differences were evaluated in order to identify the key drivers or factors, which can be applied to explain the behavior of consumer preferences. Consumers ranked these samples based on the 9-point method. An obvious preference for sample P1 was observed with 35% of participants settling on extremely liked option, giving the said sample the highest overall preference score of 7.8 ± 0.2. Further sensory and physicochemical properties, and volatiles were conducted to identify the major drivers of the consumer behavior. Sensory evaluation showed that sample P1 also produced the highest overall sensory score (85 ± 3). Though all the samples exhibited similar physicochemical attributes, significant differences were observed in the species and the concentration of volatile compounds. Accordingly, the content of free amino acids (FAAs) and lowmolecular-weight (MW) fraction (≤5 kDa) represented the trend that fell in line with sensory score. PLS2 correlation analysis indicated that physicochemical indices and volatiles could be used to explain the consumer preference, which was likely to be synergistically affected by FAAs, protein, amino nitrogen, dietary fiber, Ca, P, Fe, δ-Ε, and some volatiles, especially the positive drivers of FAAs and low MW proportion to sample P1. The work would not only provide valuable information for grading of fava pastes in the industry but also guide actual producing toward the expectation of consumers, especially increasing those positive drivers.

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