Emerging physical fields-assisted nontraditional fermentation and novel processes for tailored performance

Background

Emerging evidence has confirmed that the application of novel non-thermal physical field (NtPF) technologies in microbial fermentation holds significant potential. NtPF-assisted fermentation improves fermentation yields and conversion rates, and tailors metabolite profiles by inducing metabolic reprogramming or/and re-wiring metabolic fluxes. However, the relationship between strain metabolism and physical field stimulation, as well as their underlying mechanisms, remains controversial.

Scope and approach

This review provides the first systematic summarization over the response patterns and fermentation performance effects of microbial strains when exposed to typical NtPFs, typically involving high pressure, sonication, electromagnetic field, cold plasma, and pulsed electric field. It summarizes the general metabolic reactions and response mechanisms under sub-lethal conditions based on microbial stress physiology. By comparing the fermentation characteristics under different types of NtPFs conditions, it was attempted to establish a qualitative and quantitative relation between primary metabolic reactions improving fermentation quality and stress engineering parameters for NtPF-assisted fermentation processes.

Key findings and conclusions: NtPFs-induced metabolic fluctuations are related to the decoding of exogenous physical stimuli into biological effects. The underlying mechanisms are primarily determined by physical signal induced mechanical effects, biochemical reactions, oxidative stress responses, migration of charged particles, and the resultant modifications in gene expression. Physical field stimuli show significant potential as a switch for enhancing/attenuating microbial metabolism. Elucidating the relationship between NtPF stimuli, metabolic patterns and interspecies interactions in complex fermented matrices contributes to tailoring fermentation performance of nonuniform food systems with multi-strains consortium.