Food Microbiology
An anaerobic, spore-forming bacterium producing botulinum neurotoxin. Proteolytic types do not grow below pH 4.6, aw 0.94 or 10 °C.
The reason home-canned low-acid vegetables need a pressure canner, not just boiling water, and why a bulging or dented can is never opened.
The commercial sterility standard for low-acid canned food: a heat process delivering twelve decimal reductions of Clostridium botulinum spores.
A food with an equilibrium pH above 4.6 and water activity above 0.85, capable of supporting Clostridium botulinum growth.
The ratio of the vapour pressure of water in a food to the vapour pressure of pure water at the same temperature. It measures how much water is available for microbial growth and chemical reactions — not how much water is present.
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