Current knowledge on the VBNC and other dormant state of microorganisms in food safety: How to distinguish them?

Culture-based methods are the standard methodology in the field of food microbial safety, detection standards for food safety are largely based on such methodology, varying in food types and microbial species. Consequently, culturability is an essential trait for microorganisms and particularly important for food safety. However, the existence of those microbial cells which are nonculturable but still alive, becomes a major concern. In a larger number of cases, microbiologists are dealing with microbial cells those are viable but non-culturable (VBNC), due to either uncultured cells (currently lack of proper culturing method) or loss of culturability. (cells switch from culturable to non-culturable). Given the different terminology used across disciplines, emerging of VBNC cells in environmental, food, and clinical settings have addressed divergent consideration, among which this issue is essentially important for food microbial safety. Based on an in-depth analysis of VBNC studies from the 1980s to the 2020s, in this review, focusing on the VBNC state in food borne microorganisms, we comprehensively review the history of VBNC state, differentiate VBNC cells from other dormant cells (especially persisters), and further clarify the VBNC state in terms of distinctive features, inducing conditions, potential hazards to food safety, study procedure, detection methods, and safety control. This review may further aid in better understanding microbial survival strategy, interpretation on the culturability and viability, as well as communication of microbiologists in different fields.