Abstract:[Objective]This study aims to investigate the effects of spices on the microbial community structure and volatile flavor compounds of Fuling pickled mustard tuber and explore the correlations between dominant microbial genera and volatile components.[Method]The effects of spices on microbial community structure and volatile flavor components of Fuling pickled mustard tuber were investigated by high-throughput sequencing and headspace solid-phase microextraction (HS-SPME) coupled with gas chromatography-mass spectrometry (GC-MS). Pearson correlation coefficients were calculated to reveal the correlations between dominant microbial genera and volatile components. The mass fractions of total acids, nitrite, and reducing sugar were determined.[Result]The dominant microbial genera in the pickled mustard tuber without spices addition (control) were Lactobacillus (35.61%), Halomonas (15.13%), Leuconostoc (10.40%), Debaryomyces (77.51%), etc. In the pickled mustard tuber with spices addition, Lactobacillus (80.49%), Debaryomyces (43.17%), and unclassified_k_Fungi (28.33%) were dominant. A total of 60 volatile flavor compounds were detected in the control group, with the total mass fraction of 1 286.94 μg/kg, mainly including esters, organic sulfides, and acids. 84 volatile flavor compounds were detected in the spices addition group, with the total mass fraction of 14 304.21 μg/kg, mainly including alcohols, ethers, and acids. The pickled mustard tuber with spices addition had higher total acid mass fraction (10.95 g/kg vs. 7.14 g/kg) and higher nitrite mass fraction (5.57 mg/kg vs. 3.13 mg/kg) than the control group. Lactobacillus showed positive correlations with alcohols, ethers, alkenes, acids, ketones, and phenols (P<0.001) and negative correlations with organic sulfides (P<0.001). Debaryomyces, Halomonas, and Leuconostoc showed negative correlations with most volatile flavor components (P<0.05).[Conclusion]Spices can increase the acidity of pickled mustard tuber, the relative abundance of Lactobacillus, and the number of dominant fungi. By regulating the abundance of Lactobacillus, Wallemia, and Alternaria during the fermentation process, spices help improve the flavor of pickled mustard tuber.
