Abstract: To better understand the effect of artificial inoculation on the flavor characteristics of fermented chili, SPME-GC-MS was used to analyze the flavor composition of different types of fermented chili (natural fermentation and inoculated fermentation with 4 different Lactobacillus species). A total of 191 volatile flavor compounds were found belonging to 20 categories. Chili fermented by different strains contained very different types and amounts of volatile flavor compounds. Seventy-six flavor compounds (15 categories) were found in Lactobacillus fermentum fermented chili, 20 (8 categories) in Streptococcus lactis fermented chili, 84 (13 categories) in Lactobacillus plantarum, and 73 (11 categories) in Pediococcus acidilactici fermented chili. The results of principal component analysis (PCA) indicated that the comprehensive scores for volatile flavor compounds in chilis fermented by inoculation of Lactobacillus fermentum, Pediococcus acidilactici, Lactobacillus plantarum or Streptococcus lactis or naturally fermented were 11.28, 3.65,－0.08, －11.30 and －3.56, respectively. Five kinds of chili could be ranked in decreasing order of comprehensive score for volatile flavor compounds as follows: Lactobacillus fermentum > Pediococcus acidilactici＞Lactobacillus plantarum ＞natural fermentation＞Streptococcus lactis. Fermented chili prepared by artificial inoculation had more outstanding flavor quality than naturally fermented chili.

Key words: Lactobacillus, fermented chili, solid phase micro-extraction-gas chromatograhy-mass spectrometry (SPME-GC-MS), principal component analysis (PCA)