关键词: 川南腌菜, 生香酵母, 耐盐, 筛选, 鉴定, 特性

Abstract: Four yeast strains with a broad tolerance to a wide range of salt concentration (3%–15% NaCl concentration) and high aroma-producing ability, named YB4, YB18, YC14 and YF17, were screened from pickles from south Sichuan, China. Based on their morphology and internal transcribed spacer (ITS) rDNA sequencing, YB4 was identified as Meyerozyma guilliermondii, YB18 as Debaryomyces hansenii, and YC14 as Candida parapsilosis, whereas YF17 could not be accurately identified. The growth curves and pH of the four strains were determined. The results showed that YF17 was the first to enter the stationary phase of growth, the cell stability of YB4, YC14 and YF17 was better than that of YB18, and pH was within the acceptable range for the growth of all these strains. The acid production capacity of the yeast strains was explored at different NaCl concentrations. The results showed that the acid production capacity of YB4 and YB18 was more inhibited in the presence of 12% and 15% NaCl compared with NaCl concentrations of 6% and 9%. The acid production ability of YC14 and YF17 was less inhibited by 6% NaCl than by the other three NaCl concentrations. The acid production capacity of YB18 and YC14 increased from 48 to 72 h. This may be due to the reason that the salt adaptability of strains was stimulated during the cultivation process. In conclusion, this research lays a theoretical foundation for the preparation of fermentation agent for pickles.

Key words: pickles from south Sichuan, aroma-producing yeast, salt tolerance, screening, identification, characteristics