Initial C. perfringens counts on meat samples were w106 spores/g. Samples were mixed vigorously for 5 min using a stom- acher (Seward Stomacher, London, UK) to ensure even distribution of AK and spores in the meat. Bags were compressed into a thin layer (approximately 0.3 cm thick) and heat-sealed (Model IPK-205HK, Impak Crop., Los Angeles, CA, USA).