Infection in my backset?

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PalCabral
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Infection in my backset?

Post by PalCabral »

Last weekend I collected about 7 liters of backset from a Whiskey stripping run. It sat in a casserole for a couple of days before I got around to transfer it to a carboy and put it in the cooler. I noticed little floaters on the surface, so I reckoned Lactobacillus managed to slip in under the lid.

However, I wasnt planning on boiling the backset but adding it cold to the next batch, either during mashing or before fermentation. As a brewer I am a bit overly concerned about yeast competition in my brewery. Do I dare using the ”infected” backset in the ferment? It has no bad smell and there hasnt been any growth since I put the backset in the cooler, as far as I could see. I should be safe right?

Picture (of poor quality) of the floaters inside the carboy below.
IMG_0735.jpeg
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subbrew
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Re: Infection in my backset?

Post by subbrew »

Curious as to why using it cold rather than adding it too the gain when you gelatinize to lower the ph?

Lacto is not fast to I think if you have a good yeast pitch they will out compete and you will be done fermenting before the lacto gets to far. And it might add some nice esters you like. I have had lacto set in for a week or two before I got the stripping run and I can't say I could tell if it added esters but it certainly has not added a bad flavor.
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PalCabral
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Re: Infection in my backset?

Post by PalCabral »

subbrew wrote: Fri Apr 11, 2025 10:25 am Curious as to why using it cold rather than adding it too the gain when you gelatinize to lower the ph?

Lacto is not fast to I think if you have a good yeast pitch they will out compete and you will be done fermenting before the lacto gets to far. And it might add some nice esters you like. I have had lacto set in for a week or two before I got the stripping run and I can't say I could tell if it added esters but it certainly has not added a bad flavor.
I am using torrefied flaked corn in my mash, so no cooking or gelatinizing, just good old mashing. I use the backset to sparge the grains or more commonly just to dilute the mash a bot before I pitch. It's rare I distill and mash on the same day. For rum I heat up the dunder though, and use it to dissolve the panela.
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subbrew
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Re: Infection in my backset?

Post by subbrew »

if you are mashing for an hour at 148 F you will kill most of the lacto, 99%. If you are going to 165F or so for a sparge you are also good.
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PalCabral
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Re: Infection in my backset?

Post by PalCabral »

subbrew wrote: Fri Apr 11, 2025 11:28 am if you are mashing for an hour at 148 F you will kill most of the lacto, 99%. If you are going to 165F or so for a sparge you are also good.
I am usually mashing at 152F for 90 minutes, I should be good! Thanks subbrew! Appreciate it!
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