Molecular Insights into the Cheese Microbiome: Mapping Microbial Diversity and Functional Pathways Shaping Flavor and Quality

Cheese is a complex ecosystem of fermented foods. Heterogeneous microbial communities interact within it to determine biochemical processes, quality, safety, texture, and flavor. This review examines recent advances in molecular methods to study the cheese microbiome. It integrates conventional culture-based techniques with omics technologies, including metagenomics, metatranscriptomics, proteomics, and metabolomics. These approaches reveal the composition and activity of starter and non-starter lactic acid bacteria (LAB), as well as molds and yeasts during cheese ripening. The analysis focuses on microbial interactions in key processes such as acidification, proteolysis, lipolysis, and volatile aroma compound formation. Functional genes encode proteolytic and lipolytic enzymes that produce primary flavor precursors. Non-starter LAB and indigenous microbiota contribute significantly to aroma complexity and texture development. Molecular profiling not only tracks microbial succession over time and how their environments affect them, but also the influence they have on terroir-specific characteristics of artisan cheese. This review paper presents various multi-omic approaches, including functional analysis, creative flavor enhancement, and metabolic pathways through functional analysis, to help facilitate product consistency. Microbial community-based approaches are helpful because they provide a basis for reducing the variability of products produced from a given raw ingredient, verifying the authenticity of a given ingredient, and for making informed sensory modifications (targeted sensory) to cheese produced by both artisans and industrial producers. This paper also discusses some of the obstacles associated with integrating and standardizing the data generated in the field of microbiome research; as well as identifies areas where precision fermentation and data-informed process control may be able to be implemented to improve the consistency and quality of cheese production.