Clostridium Botulinum in Plant-Based Proteins

Highlights

• What is Clostridium botulinum?
• What risks are associated with C. botulinum in plant-based proteins?
• How to ensure food safety

According to the FSMA final rule, animal and plant-based protein producers must implement a written food safety plan that includes a hazard analysis and preventive controls. Control measures to prevent botulism in foods include reducing the pH by acidification, reducing moisture levels, adding antimicrobials and preservatives, and temperature control. 

Clostridium botulinum spores are ubiquitous, found in both soil and aquatic environments. C. botulinum may grow in foods under anaerobic and modified atmospheric packaging (MAP) conditions and produce neurotoxins. Many foods provide the nutritional requirements for the growth of C. botulinum and the necessary growth conditions (e.g.,> pH 4.6 and > Aw 0.95). Especially vacuum-packaged products may pose a high risk of C. botulinum growth and toxin production.

The plant-based protein industry is growing rapidly and poses unique food safety challenges. Products with plant-based proteins have become a popular source of protein and an alternative to meat products. C. botulinum spores are frequently isolated from raw vegetables. Ingredients used in plant-based products typically include various protein sources (chickpea, pea, soy, wheat), vegetables, herbs, and spices that may be sources for C. botulinum spores.

The safety of plant based products relies mainly on formula-based hurdle effects, heat treatment, and cold storage. Cooking destroys vegetative cells, but spores of C. botulinum can survive pasteurization temperatures. An anaerobic environment promotes the growth of C. botulinum and toxin production. Non-proteolytic strains are capable of growth and toxin formation even at refrigeration temperatures.

To ensure safety against this pathogen, food manufacturers should gather scientific and technical data to demonstrate the effectiveness of their preventive controls to control C. botulinum. This microorganism can produce toxins when a product is exposed to temperatures favorable for growth. Therefore, an inoculated pack/challenge study should be conducted to demonstrate the microbiological stability of the product against C. botulinum during storage.

As one of a few laboratories licensed to work with this microorganism, Mérieux NutriSciences Food Science Center has a global reputation in C. botulinum detection and challenge studies. Samples are analyzed for viable C. botulinum cells, spores, and botulinum neurotoxins. The Food Science Center specializes in conducting inoculated pack studs and process validation studies. All quality systems meet the federal mandates required for select agent testing.