High prevalence of Clostridium botulinum in vegetarian sausages

• Published in: Food microbiology Vol. 91; p. 103512
• Main Authors: Pernu, Noora, Keto-Timonen, Riikka, Lindström, Miia, Korkeala, Hannu
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01-10-2020
• Subjects: Botulinum Toxins - genetics; Botulism; Clostridium botulinum; Clostridium botulinum - classification; Clostridium botulinum - genetics; Clostridium botulinum - growth & development; Clostridium botulinum - isolation & purification; Colony Count, Microbial; Consumer Product Safety; Food Handling - methods; Food Microbiology; Food, Preserved - microbiology; Genotype; Meat-free sausage; Spores, Bacterial - classification; Spores, Bacterial - genetics; Spores, Bacterial - growth & development; Spores, Bacterial - isolation & purification; Vegetable; Vegetables - microbiology; Vegetarian; Vegetarians; Clostridium botulinum; Botulism; Vegetarian; Vegetable; Meat-free sausage
• DOI: 10.1016/j.fm.2020.103512
• EISSN: 1095-9998
• ISSN: 0740-0020

Clostridium botulinum is a significant food safety concern due to its ability to produce highly potent neurotoxin and resistant endospores. Vegetarian sausages have become a popular source of plant protein and alternative for meat products. While vegetarian sausages have not been linked to botulism, numerous outbreaks due to preserved vegetables suggest a frequent occurrence of C. botulinum spores in the raw material. The product formulation of vegetarian sausages involves limited NaCl and preservatives, and shelf-lives may be several months. The safety of vegetarian sausages thus relies mainly on heat treatment and chilled storage. The main food safety concern is C. botulinum Group II that can grow and produce toxin at refrigeration temperatures. Here we show a high overall prevalence (32%) of C. botulinum in 74 samples of vegetarian sausages from seven producers. Both Groups I and II strains and genes for neurotoxin types A, B, E and F were detected in the products. The highest cell counts (1200 spores/kg) were observed for C. botulinum Group II in products with remaining shelf-lives of 6 months at the time of purchase. We conclude that vacuum-packaged vegetarian sausage products frequently contain C. botulinum spores and may possess a high risk of C. botulinum growth and toxin production. Chilled storage below 3°C and thorough reheating before consumption are warranted.
•High prevalence of Clostridium botulinum found in vegetarian sausage products.•C. botulinum Groups I and II, and genes for neurotoxins A, B, E, and F were found.•C. botulinum Group II is the main food safety concern in chilled packaged foods.