Rum Run Bitter

Anything to do with rum

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Powder Monkey
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Joined: Fri Jan 22, 2021 7:15 am
Location: Michigan

Rum Run Bitter

Post by Powder Monkey »

I ran a batch of rum today and the entire run had a bitterness to it. Looking for advice/reassurance. Here’s the background and what I think happened.

I have many rum runs under my belt and I think I just got complacent with this one, got an infection making acetic acid and that’s that. I typically dump enough hot dunder back into my fermenter to sterilize and then just add new yeast. Last time I added cold water first and kept it under ferment temps to try and restart the old yeast. I’m not super sanitary in my ferments. It hadn’t really taken off the next morning so I added fresh yeast and nutrient which did the trick.

My rum ferments are typically slower over 7ish days. I recall checking the pH but didn’t keep notes, maybe 4ish to start. I use an aquarium heater and when the ferment was over it gets turned off and essentially is refrigerated in my slightly heated barn at 40F during winter. I didn’t get to run it for a month or so but when I did today it did have a vinegar smell. My sensory skills are not refined but it certainly was different aroma than my typical ferments. Nothing ventured nothing gained so I ran it. Flute. 4 plates is my standard. Yield was much lower than expected.

The bitterness is present through the entire run. I assume my acetic producing infection outpaced my etoh producing yeast. I assume this distillate is now solvent etc at this point? Am I correct that it is an acetic component contributing to the bitterness? I cant imagine this would make something desirable if aged? I also doubt this could be removed even if re ran for a close to neutral spirit? Thanks for sharing any similar experience.
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still_stirrin
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Re: Rum Run Bitter

Post by still_stirrin »

Acetic acid IS vinegar. And you confirmed this with your comment on the “smells like vinegar” notes. The “vinegar bug”, some call it a “mother”, because it will set in and consume the sugars as well as the alcohol in your fermenter. Acetobacter is not the “wild flora” you want in your brewhouse…unless you’re trying to make your own malt vinegar. Like to eat fried fish?

So, your unsanitary processes may need to be cleaned up. It is difficult to get rid of bacteria in the brewhouse without a thorough sanitization regimen. Brewery cleaners, like Star-San will help. But if you’re fermenting in plastic buckets, your best option may be to replace the buckets. It is extremely difficult to kill bacteria because it will embed into the plastic fibers. Glass and stainless steel fermenters will tolerate the “acid sanitizers” necessary to kill bacterial contamination. Hot water won’t do it alone.
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Powder Monkey
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Joined: Fri Jan 22, 2021 7:15 am
Location: Michigan

Re: Rum Run Bitter

Post by Powder Monkey »

Thanks SS. Brute cans are my fermentation vessel of choice right now. I distill in my shop/barn and working on an instant hot water heater and sink for easier cleaning options. I did use PBW and star San on things yesterday. Appreciate the advice.
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