Abstract: In order to explore the differences in the flavor characteristics of fermented hot pepper prepared from different varieties, the volatile compounds of fermented hot pepper made from four varieties widely planted in Guizhou, Huangping line (HP), Linka (LK), Qian 8 (Q4) and Layan 101 (LY), were analyzed by headspace solid-phase microextraction (HS-SPME) coupled with gas chromatography-mass spectrometry (GC-MS). The results showed that 60, 71, 55 and 65 volatile compounds were detected in HP, LK, Q4 and LY, respectively. Acetic acid was the most abundant volatile component in HP, LK and Q4, while geraniol was the most abundant volatile component in LY. In total, 24 volatile compounds were common to the four fermented hot peppers. Correlation analysis showed significantly negative correlations (P < 0.05) between alcohols and alkanes and alkenes, between esters and ketones. Conversely, there was a significantly positive correlation between alkenes and alkanes. Using orthogonal partial least squares-discriminant analysis (OPLS-DA), more than 10 differential volatile compounds were selected among the four varieties, with 2-phenylethyl acetate being the major one in HP vs Q4 and LK vs Q4, acetic acid being the major one in LY vs Q4 and LK vs LY, and phenylacrylonitrile being the major one in LK vs HP. A comprehensive quality evaluation model was established based on nine classes of volatile compounds in fermented peppers, and the decreasing order of volatile flavor quality was HP > LY > LK > Q4. This study could provide a reference for the choice of raw materials for fermented peppers.

Key words: fermented hot pepper; volatile compounds; correlation analysis; differential substances; comprehensive evaluation