Min pasteurization temp? I accidentally killed my lacto starter

Ingredients
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I left my 1-gallon lacto starter overnight with two brew belts wrapped around it, and then a towel around that. This morning it smelled a little bit tart, but not nearly as tart as usual. I checked the temp, and it was at 141*F, so it’s probably dead, right? I unplugged one of the belts, and I’ll see where the temp is this afternoon and add some more grain.

I’ve found some pasteurization charts online, but I can’t find the highest temp you can hold something indefinitely and not get any pasteurization. Also, has anyone tried to pasteurize wort just by using brew belts and insulation? I’m not sure if two would be able to get 20L or so of wort up to temp.

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According to the FDA for milk the minimum temp is 145F/63c for 30 minutes and 155*/69* if sweeteners are added.  Not sure if the same holds true for beer.

This says 122-131 for beer http://www.pasteurbrewing.com/articles/beer-wine-a-fermentation/the-pasteurization-of-beer.html No idea if it means anything though. This says 176-212 http://www.vency.com/webPASTEURIZATION.html .

Otherwise, I can’t find much and what I can find indicates it depends greatly on the strain of lacto.

Sou

Edit: RDWHAHB and good luck.

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The curve is asymptotic. I’ve seen numbers quoting as low as 135* for like 90min. So the curve seems to flatten around 130* or so. If I had to do a WAG, I’d say maybe 120* is the upper end you can hold indefinitely, but it might be higher or lower. I try to keep my sour starters around 110*, but this one got away from me.