Analysis of Volatile Flavor Substances of Chinese Water Chestnut in Different Steaming and Boiling Time Based on Sensory Evaluation and E-nose

On the basis of sensory evaluation, the volatile flavor compounds of Chinese water chestnut (CWC) in different steaming and boiling time were analyzed by E-nose technology, the data change from sensor was observed through radar chart, and the particular data was analyzed with principal component analysis (PCA) and linear discrimination analysis (LDA). According to the sensory evaluation results, the best steaming and boiling time of CWC without peel were 20 min, and the best steaming and boiling time of CWC with peel were 30 min. According to the E-nose analysis results, the volatile flavored substances of CWC in different steaming and boiling time were mainly sulfide, in addition to small amounts of methyl, aromatic and organic sulfur compounds. Compared to fresh CWC, the smell difference of CWC was obvious in different steaming and boiling time. PCA had better response to the smell of CWC at different steaming and boiling time. In LDA analysis, the total contribution rate of LDA was more than 90%, slightly lower than that of PCA analysis, which could also distinguish CWC with different steaming and boiling time. The results of sensory evaluation were consistent with the radar diagram, PCA and LDA of E-nose.The E-nose analysis based on sensory evaluation was not only more objective and accurate than single sensory evaluation, but also could quantitatively evaluate the change rule of volatile flavor substances of CWC in different steaming and boiling time, which had a certain guiding role in the quality control of CWC processing and daily steaming and boiling.