Microbial composition, dynamics, and functional roles in jinhua ham fermentation: integrating starter cultures and...

Jinhua ham, a traditional Chinese dry-cured meat product with nearly a millennium of production history, derives its characteristic colour, layered aroma, and umami-rich taste from the coordinated biochemical activity of a dynamic microbial ecosystem across an eight-to-ten-month fermentation timeline. This review provides a critical synthesis of research between 2018 and 2025 on microbial composition, community dynamics, functional roles, safety risks, starter culture applications, and multi-omics characterisation of Jinhua ham fermentation, unified by precision fermentation as an organising framework. High-throughput sequencing has established that halotolerant bacterial genera, Staphylococcus, Psychrobacter, Halomonas, and Lactobacillus, and fungal communities comprising Aspergillus, Debaryomyces, Meyerozyma, and Penicillium undergo deterministic, physicochemically driven succession, with their enzymatic activities governing proteolysis, lipolysis, volatile compound formation, colour stabilisation, and the accumulation of biogenic amines, mycotoxins, and antimicrobial resistance genes (ARGs). Autochthonous starter cultures, including Staphylococcus xylosus, Lactiplantibacillus plantarum, and Penicillium aethiopicum, improve process controllability, safety, and sensory consistency, yet their mechanistic basis and validation remain incompletely established. Genomic and metabolomic approaches have generated datasets, but integrated metagenomics-metabolomics coupling, capable of linking microbial gene networks to flavour compound production, and metatranscriptomic characterisation of gene expression remain the unmet methodological needs. Five research directions are proposed: achieving species-level microbial resolution through long-read sequencing and longitudinal sampling; validating flavour-forming pathways through isotopic tracing and controlled inoculation; standardising analytical protocols for cross-study comparability; conducting starter culture and ARG safety validation; and developing low-salt fermentation strategies. Together, these directions define the research investment required to advance Jinhua ham production from empirical tradition to precision-engineered consistency.