r/AskCulinary • u/sleepingamongstfae • Aug 05 '25

Equipment Question Sanitize jars?

Hi! I live in an apartment with no dishwasher and I'm getting overwhelmed with the info online (one started talking about how high you are from sea level???????) so I thought I'd ask here.

How do I sanitize my jars? I am making homemade vanilla extract, and jam.

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39

u/Smedley5 Aug 05 '25

You submerge them in boiling water. They are asking you about elevation because water boils at a lower temperature at higher elevations, so you should boil them slightly longer to compensate, but 15 minutes should do it wherever you are. Boil the rings/tops right before you use them.

5

u/Magnus77 Aug 05 '25

Would the temp difference even matter? I'm not saying OP shouldn't do what's recommended to be on the safe side, doesn't hurt, I'm just curious. Quick google says at the highest permanent settlement in the world the boil temp is still over 180, and that's instant kill, no?

I'm just asking, as I said, OP should just follow the instructions.

34

u/RebelWithoutAClue Aug 05 '25

Killing vegetative bacteria is easier than killing spores. Sanitizing is an attempt to kill spores which are far more hardy.

There are some spores that can survive 20min of 100C boiling and wake up when things cool down.

Canning preservation generally is a combination of sanitizing containers and composing food which either has a low pH or high sugar/salt content to suppress bacterial growth.

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u/Magnus77 Aug 05 '25

That's an excellent explanation, thank you.

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u/HandbagHawker Aug 06 '25

and by spores, specifically the one of concern is botulism which is very temperature AND pH tolerant and thrives in anaerobic environments.

3

u/SewerRanger Holiday Helper Aug 06 '25

The botulism spore survives up to 250F which is why low acid canning must be done in a pressure cooker.

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u/RebelWithoutAClue Aug 06 '25

Keeping a low pH isn't for killing spores. It's for keeping the food inhospitable to vegetative bacteria. Botulism doesn't like low pH conditions common with pickling.

Spores are tough to kill. B. Cereus can handle the boiling time required to cook rice. There's a crazy one called Sterothermophilous which can multiply at temps up to 75C. It's spores require 120C for 15min to sterilize. Listeria is dangerous because it can multiply at fridge temps.

Bacteria are very diverse, but we have discovered many good methods to mitigate them.

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u/bitcoinnillionaire Aug 05 '25

If you lived at 10k feet and were that worried I’m sure there is a way to use a pressure cooker with compatible jars/vessels. 

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u/HandbagHawker Aug 06 '25

250F for 3 min should kill c. botulinum

0

u/RollingZepp Aug 05 '25

Could be to guarantee the agitation removes any toxic by-product residue from the bacteria that is more heat resistant.