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will pressure cooker kill all micro organisms

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MHBT

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I needed a growler cap so i rummaged thru everything and found one on a empty growler in my garage, yes the inside seal was covered in mold, so i cleaned it with pbw and put it in a pressure cooker for 45+ mins, i can still see remnants of mold on it but i can be 100% certain nothing lives on this cap right?
 
Well, the high pressure elevates the boiling temperature and thus allows the temperature to reach high enough to kill microbes and spores.

On the other hand, mold spores are basically everywhere so as soon as it was exposed to the air in your house it was contaminated again.
 
Use the tip of a knife to pry out the inner clear piece and clean that stuff out. If you're talking about mold stains on the rubber seal, try a soak in mild bleach solution, rinse well then dip in starsan before use. The mold you can see may be dead but it will still give your beer a nasty flavor.
 
The mold is dead if the temp has been high enough. Even if there are some remnants left. But there is a wide variety of mold species and some spore forming molds can be quite temp resistant so that if you are unlucky, a pressure cooker with rather low pressure may not kill all the spores. So the answer is that there are different types of cookers and it depends on the pressure (and the exact mold species). If there is a problem, you will probably notice the it when you use the growler... If there is a lot of visible mold left I would clean it more carefully, cause molds may contain unhealthy compounds that could survive the heat.
 
Probably...but you can't really be that confident about it whilst there's visible residues on the cap. It's not so much the residues as such, but they may hide biofilms that shield spores from the steam which is what really kills in pressure cookers. Once the residue was off I'd be happy to use it until a problem was encountered. But keep an eye on it, it would be the first growler I'd empty of the batch and I wouldn't use it for extended ageing.
 
i needed the cap to make a yeast starter, i was trying the "shaken not stirred method" and to make things even worse on top of the moldy cap i pressure cooked for 45-60 mins, i noticed dog hair floating in the starter( i thought i cleaned) so i dumped the starter down the drain too many strikes against me, i would rather waste money then gamble on a batch esp a lager.anyway thank you for your feedback
 
That's what I would have done - I can cut some slack for finished beer, but for starters I am paranoid about sanitation, as any mistakes can get multiplied 16x or more.
 
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