Microbial kinetics revealed the deterioration mechanism of flavor quality of modified atmosphere packaging Tricholoma matsutake

This study examined the impacts of varying modified atmosphere (MA) compositions on the storage quality, volatile organic compounds (VOCs), and microbial community dynamics of wild Tricholoma matsutake sourced from Shangri-La, Yunnan Province, during storage at 4 ℃. Four experimental groups were compared: an air control (CK) and three MA treatments with gas ratios as follows: A (9% O₂ + 9% CO₂ + 82% N₂), B (5% O₂ + 15% CO₂ + 80% N₂), and C (1% O₂ + 21% CO₂ + 78% N₂). Among these, Group C exhibited the optimal preservation efficacy, extending the shelf life to 24 d while maintaining weight loss below 5%. This treatment significantly delayed the respiratory climacteric peak, restricted polysaccharide degradation to ≤ 25%, inhibited malondialdehyde (MDA) accumulation, and preserved cellular ultrastructure integrity. Using headspace solid-phase microextraction coupled with gas chromatography-tandem mass spectrometry (HS-SPME-GC-TQ-MS), a total of 85 VOCs were identified through relative odor activity value (ROAV) and variable importance in projection (VIP) analyses. 13 key flavor compounds were characterized. ( E )-2-octenal and 1-octen-3-ol emerged as dominant VOCs during the early and mid-storage stages, whereas spoilage-associated compounds—including 3-methyl-1-butanol, styrene, and benzaldehyde —accumulated in later stages. 16S rRNA gene sequencing revealed that Pseudomonas , Serratia , and Chryseobacterium were the primary spoilage bacteria. KEGG functional annotation indicated enhanced genetic information processing and cellular metabolic activity in the late storage phase, which accelerated mushroom deterioration. ITS sequencing further showed that symbiotic fungi preliferation of Inocybe , Tricholoma , and Mucor species. Pearson correlation analysis demonstrated that most spoilage bacteria were negatively correlated with freshness-related VOCs, whereas spoilage fungi exhibited positive correlations with 2-nonenal and 3-methyl-1-butanol. These findings suggest potential microbial competition and antagonism interactions during storage. Collectively, this research elucidates the mechanisms by which MA storage mitigates quality deterioration in T. matsutake by regulation of microbial succession and flavor metabolism, thereby providing a theoretical basis for optimizing preservation technologies. • MAP at 4 ℃ extended T. matsutake storage to 24 days. • 13 key VOCs identified for rapid, non-destructive quality monitoring. • Microbial flora dynamics revealed metabolic pathways leading to quality loss. • Microbial CoNet indicates that Pseudomonas and Serratia are core spoilage bacteria. • Bacteria (-) and fungi (+) with VOCs, driving flavor loss in matsutake preservation.