Clostridium botulinum Ionizing Radiation D‐Value Determination Using a Micro Food Sample System

A miniaturized system for rapid and accurate irradiation D‐value determinations was evaluated. The test units consisted of pork, ham or chicken substrates inoculated with a mixed suspension of Clostridium botulinum spores, sealed inside polypropylene cryotubes at vacuum levels of 250, 125 and 50 torr. Samples were irradiated with ⁶⁰Co gamma rays at −30 ± 10°C up to a dose of 1.8 Mrads. D‐values were in close agreement with historical determination for the substrates and conditions tested. The D‐value estimates encompass a standard error of 0.025 Mrad at p < 0.05. Replicate experiments conducted on different days demonstrated a high degree of reproducibility.