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For thousands of years, humans have enjoyed the novel flavors, increased shelf-life, and nutritional benefits that microbes provide in fermented foods and beverages. Recent sequencing surveys of ferments have mapped patterns of microbial diversity across space, time, and production practices. But a mechanistic understanding of how fermented food microbiomes assemble has only recently begun to emerge. Using three foods as case studies (surface-ripened cheese, sourdough starters, and fermented vegetables), we use an ecological and evolutionary framework to identify how microbial communities assemble in ferments. By combining in situ sequencing surveys with in vitro models, we are beginning to understand how dispersal, selection, diversification, and drift generate the diversity of fermented food communities. Most food producers are unaware of the ecological processes occurring in their production environments, but the theory and models of ecology and evolution can provide new approaches for managing fermented food microbiomes, from farm to ferment.
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Novel fermentations integrate traditional practice and rational design of fermented-food microbiomes
Fermented foods and beverages have been produced around the world for millennia, providing humans with a range of gastronomic, cultural, health, and scientific benefits. Building on these traditional forms, a conver- gence of factors, including culinary innovation, globalization, shifts in consumer preferences, and advances in microbiome sciences, has led to the emergence of so-called ‘novel fermentations’. In this review, we define novel fermentation as the confluence of traditional food practices and rational microbiome design. Using principles of microbial ecology and evolution, we develop a microbiological framework that outlines several strategies for producing and characterizing novel fermentations, including switching substrates, engrafting target species, assembling whole-community chimeras, and generating novel phenotypes. A subsequent analysis of existing traditional ferments points to gaps in ‘fermentation space’ where novel ferments could potentially be produced using new combinations of microbes and food substrates. We highlight some impor- tant safety and sociocultural issues presented by the repurposing and modification of microbes from tradi- tional ferments that fermented-food producers and microbiologists need to address.
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- PAR ID:
- 10563000
- Publisher / Repository:
- Cell Press
- Date Published:
- Journal Name:
- Current Biology
- Volume:
- 34
- Issue:
- 21
- ISSN:
- 0960-9822
- Page Range / eLocation ID:
- R1094 to R1108
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1016/j.cub.2024.09.047
