Milk contains 4×10⁵ C. botulinum spores/mL (D=1.2 min at 121.1°C) and 7×10⁶ L. monocytogenes spores/mL (D=.9 min at 121.1°C). At uniform121.1°C, find minimum heating duration for spoilage probability1 per 1000 cans, in minutes to two decimals.
For the intended normalized one-mL container calculation, require surviving count .001. Botulinum requires $1.2\log_{10}(4\times10^5/.001)=10.3225$ min; Listeria requires $.9\log_{10}(7\times10^6/.001)=8.8606$ min. The controlling time is **10.32 min**. Actual can volume is not supplied; for V mL, replace initial counts by their products with V. Thus a general per-can duration needs that missing volume.
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