Pasteurization & Sterilization Temperatures

 thermal treatment of a wort can be accomplished by heating to 63° C (145° F) and maintaining for 30 minutes or, alternatively, heating to a higher temperature, 72° C (162° F), and holding for 15 seconds or  89ºC (191ºF) for 1.0 second which will kill everything except certain spores that can only be sterilized with pressurized steam. Luckily, those fungi (botulism) only reproduce at a pH of 4.5 and above and in anaerobic (low oxygen) conditions. If you practice good sanitation, your fermentation worts and must will be fine.

Storing Wort Runs the Risk of Botulism

Denaturing of enzymes