Manufacture of Traditionally Fermented Vegetable Products: Best Practice for Small Businesses and Retail Food Establishments

Fermentation has a long tradition of improving the shelf life, acceptability, and safety of some food and beverages. Under the Food Safety Modernization Act, a business that manufactures fermented foods may be required to conduct a risk analysis and establish pertinent preventive controls. Retail food establishments operating under the FDA Food Code must often seek a variance for manufacture of fermented foods and beverages. Developing food safety programs can be a challenge for small-scale producers with little access to training and resources, especially as manufacture of fermented products involves microbiologically complex systems that may not be effectively or appropriately managed by standard time-temperature controls. We review the science behind traditional vegetable fermentation processes, e.g., cabbage, cucumbers and peppers, and discuss identification of relevant hazards based on intrinsic and extrinsic factors inherent in the fermentation systems that influence microbial survival. We advocate for one Critical Control Point (CCP) in the manufacture of traditionally fermented vegetable products, namely a steady and sustained pH decline to < 4.6. We outline additional Control Points (CPs) at key steps, i.e., vegetable preparation and salt addition; fermentation time and temperature; refrigerated storage; and/or packaging for shelf stability. We illustrate these best practices with an example of kimchi manufacture.