Correlation Analysis between Microorganisms and Volatile Flavor Substances during the Post-ripening of Fermented Bamboo Shoots with Chopped Pepper

Abstract

The changes of microbial diversity and volatile flavor compounds in fermented bamboo shoots with chopped pepper during post-ripening were determined by high-throughput sequencing and headspace solid phase micro-extraction (HS-SPME) couple to gas chromatography-mass spectroscopy (GC-MS), and the correlation between them was analyzed. The results showed that Colletotrichum, Penicillium, Xanthomonas, Erwinia, Ralstonia, Pseudomonas, Pediococcus and Enterobacter were dominated in fermented bamboo shoots with chopped pepper during post-ripening. A total of 71 volatile compounds were detected, and the total content of volatile compounds increased from 406.57 to 900.08 μg/kg over the ripening period. The results of principal component analysis (PCA) showed obvious separation between samples at the early and late ripening stages. Based on variable importance in projection (VIP) greater than 1 from orthogonal partial least squares-discriminant analysis (OPLS-DA), 28 important metabolites were identified. The Pearson correlation coefficient showed that bacteria had a greater impact on flavor compounds than fungi, and the dominant bacteria were positively correlated with most flavor substances. This study will provide a theoretical basis for improving the flavor quality of fermented pepper products during post-ripening.

Keywords

• fermented bamboo shoots with chopped pepper; post-ripening; microbial diversity; volatile flavor compounds; correlation analysis