Progress on the content, formation mechanism and biological function of propionic acid in fermented foods

Propionic acid is a major metabolite produced during food fermentation, which plays an important role in the regulation of the intestinal health and physiological homeostasis. Low doses of propionic acid have anti-inflammatory, anticancer, improve intestinal barrier function, treatment of atherosclerosis, and neuroprotective effects, but high doses of propionic acid have adverse effects on metabolic and neurological disorders, such as autism spectrum disorders and hyperinsulinemia through inhibition of neuronal development and activation of insulin resistance. At present, the research on the formation mechanism and biological function of propionic acid is still in the initial stage, and the mechanism of propionic acid is uncertain. In this paper, the content and formation mechanism of propionic acid in fermented foods were summarized, and the progress on the biological function of propionic acid was highly concerned, which provided a theoretical basis for the subsequent development of the potential value of propionic acid.