Growth and toxin production by Clostridium botulinum in fish (Mugil cephalus) and shrimp (Penaeus indicus) tissue homogenates stored under vacuum

Toxin production by Clostridium botulinum types A–E in mullet and shrimp tissue homogenates stored between 4 and 30°C under vacuum for 6 weeks was evaluated. Mullet and shrimp tissue homogenates were inoculated with C. botulinum spores, then packaged under vacuum and held at 4, 10, 15 and 30°C. At 30 and 15°C storage, growth and toxin production by types A–E resulted in both mullet and shrimp tissue homogenates. Only type E toxin was observed in the homogenates held at 4 and 10°C. The storage temperature and the growth substrate markedly influenced the toxin titres.