The occurrence and growth of Clostridium spp. in vacuum‐packed bacon with particular reference to Cl. perfringens (welchii) and Cl. botulinum

Summary Presumptive Clostridium spp. were detected in 234 of 263 25 g samples of vacuum‐packed bacon, sixty‐four of which contained Cl. perfringens and eleven Cl. botulinum (ten confirmed as type B and 1 type A). Growth of presumptive Clostridium spp. occurred in vacuum packs stored at 15°, 20° and 25°C but growth of Cl. perfringens or Cl. botulinum never occurred. Growth of clostridia was not related to any particular curing process, though some of the results suggested that the role of nitrate in their control should be further investigated. In one subsequent batch of unsliced collar bacon, of twenty‐six 175 g samples, nineteen contained Cl. botulinum type A.