Five non-proteolytic C. botulinum strains (kindly provided by Dr
Pete McClure, Unilever, UK.) were used to inoculate minced
chicken. Three of these were type B (BL 23, BL192, BL151) and two
were type E (BL34, BL77). Cultures were stored on beads in cryovials
(Pro-Lab Diagnostics, Richmond Hill, Canada) at 80 C until
required. All liquid media were steamed for 10 min to drive off
dissolved oxygen and cooled prior to use.