Consistent off flavour

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bonecitybrewco

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Hey all,

A long time ago I posted about a consistent off flavour I was getting. I've literally done everything I can think of to try and isolate this solvent like smell and after-belch (which sounds as disgusting as it is).

I'm at my wits end here and not sure what I can do about it. I've isolated it to one of the following variables. It is either a batch of Cascade hops or one of my glass carboys. Has anyone EVER heard of a glass carboy having micro scratches that could harbour bacteria from an oxygen cleaner plus both starsan and iodophor? Better yet, has anyone ever had a batch of hops lead to that significant of an off flavour?

I'm at my end here. Not even sure how to approach it.

What makes me think it's the hops is this: only the batches I've used these Cascades in have produced this flavour. The ONLY way it is a carboy causing it is in the random chance that it's the same carboy on every batch that has this issue.

The reason I know it's not the process is that I've had many great batches with no off flavour and only a few with this specific off flavour using the same processes on all batches in terms of cleaning and sanitizing and everything else.

I cannot nail down what this off flavour is though. It's solventy and produces hot burps. That I know.
 
Are you running your fermentation temps too high? High temps can allow yeast to give off fusel alcohols, which may cause a hot, solvent-like flavor.

Otherwise, I have never heard of anyone having problems with scratched glass carboys, though it's certainly possible if you clean it with something too abrasive. If the glass does have scratches, microbes could accumulate there.
 
Are you running your fermentation temps too high? High temps can allow yeast to give off fusel alcohols, which may cause a hot, solvent-like flavor.

Otherwise, I have never heard of anyone having problems with scratched glass carboys, though it's certainly possible if you clean it with something too abrasive. If the glass does have scratches, microbes could accumulate there.

Fermentation temps are very controlled. And vary by fermentation.

The carboys were inherited so before me I can't speak to how they were treated. It's even possible it was used for wine at one point. It seems the obvious choice to eliminate that factor would be to switch out for PET carboys or similar however I'd rather not throw out perfectly good glass carboys or spend $ on new fermenters when I don't need them if you know what I mean? I'm more curious since the hops are another common factor. In this batch it seemed to taste fine in a gravity sample a few days ago and then post dry hop and carb in keg it changed.
 
If you do things differently next brew, only change one variable. Try using a different vessel for fermentation. If that fixes it, then it's the carboy.

Yeah this is my thought. Just isolate that carboy and see what happens.
 
Have you tried swapping out your tubing?

All other equipment has been replaced or changed or brewed on other equipment completely. This happens randomly. In a year of brewing let's say 1 batch per month, I will randomly have 3 batches in that year with the same off flavour.
 
Are you doing anything to treat your water? Water salts, acid additions, campden tablets, etc?
 
Do you buy your hops in bulk? Are they all from the same batch? I have a hard time believing it’s the carboy.

The cascades were purchased in bulk 1 lb bags. All batches with this flavour issue used the cascades from the same bag...
 
The cascades were purchased in bulk 1 lb bags. All batches with this flavour issue used the cascades from the same bag...
Seems very suspicious. Use Cascade pellets for your next brew. Since equipment was replaced another possible area for off flavor is brewing water additions if you are trying to duplicate a certain cities water profile for the style of beer.
 
Seems very suspicious. Use Cascade pellets for your next brew. Since equipment was replaced another possible area for off flavor is brewing water additions if you are trying to duplicate a certain cities water profile for the style of beer.

Nope. Build my own profiles based on Bru'n water. Not trying replicate any city. And these are pellets.
 
If you think it is the carboy, why not heat sterilize it to remove that as a variable? Usually once a year I will do my carboys. 1 hour in the oven @ 350 will kill anything even in scratches etc.

Just make sure it is bone dry, not a single drop of water in it, or it could cause cracks. Also cool it slowly, crack the oven open a bit once done and let heat slowly escape for another hour or so before moving.
 
Nope. Build my own profiles based on Bru'n water. Not trying replicate any city. And these are pellets.
Could it be a storage problem with the bulk hop pellets? I've been repackaging my bulk hop pellets in 1 and 2 ounce vacuumed sealed packages. Keep them in the freezer.

I know it is difficult to deal with since I'm just coming back from dumping two infected beers with several other beers in between without infection. I think I narrowed it down to the bag used to strain out hop debris during the pour into the carboy. Some times the bag was clean and other times it wasn't. Now I boil the bag before each use.

I would use new packages of hops if there is no chance a piece of equipment may be the cause of the off flavor.
 
Could it be a storage problem with the bulk hop pellets? I've been repackaging my bulk hop pellets in 1 and 2 ounce vacuumed sealed packages. Keep them in the freezer.

I know it is difficult to deal with since I'm just coming back from dumping two infected beers with several other beers in between without infection. I think I narrowed it down to the bag used to strain out hop debris during the pour into the carboy. Some times the bag was clean and other times it wasn't. Now I boil the bag before each use.

I would use new packages of hops if there is no chance a piece of equipment may be the cause of the off flavor.

Yeah the hops are frozen/vac sealed as well. I don't use anything I can't sanitize and therefore cold crash before transferring making sure to not allow sanitizer to backflow into the fermenter. I'm really at a loss short of just switching the other fermenter exclusively for a year and seeing what happens. Thanks for all the replies so far.
 
So I just remembered that one of the batches was split between two carboys (10 gallons) And that one half of the batch was perfect and the other half had this flavour. Does this make any sense regarding the carboy?!
 
After reading some more I have to wonder if it's possible this is being caused by StarSan? I use RO for brewing and add campden just to be sure but I use tap water for star San. In this batches case, I tried to empty the fermenter as best I could of foam before transferring to it however there obviously was still some there. Also there would have been foam in the bottom of the keg while transferring there as well. How do people normally manage this? In the case of this batch the flavour didn't show up until after carbonated.
 
After reading some more I have to wonder if it's possible this is being caused by StarSan?

StarSan can cause an off-flavor, but it seems the general opinion here is that it takes a LOT of it to do so. There's a reason "Don't fear the foam!" is a mantra here on HBT. We all have that left-over foam in our carboys/fermenters/bottles/kegs and it really isn't an issue. The volume of the foam looks huge, but once all the bubbles pop the actual amount of liquid SS that was present in all those bubbles is really tiny. If you'd had an inch or so of liquid SS in the bottom of your carboy that you were shaking around inside to sanitize it prior to filling, and then forgot to pout it out beforehand... that's the amount of SS that might cause an off flavor.
 
And just another thought: compare the cost of one pound of hops or one fermenter (even a good glass one) to the cost of the raw materials for a 5 gallon brew. Personally, I'd dump them both. AT LEAST "red tag" them and set them aside while you use other materials and carboy to make a couple more batches. If that solves the problem, then I'd definitely chuck them both. No sense wasting any more time/money/effort/taste buds.
 
Seems to me you answered your question. You split a batch--one was good and one wasn't. seems like you need to eliminate the carboy used in the bad batch.
 
So I just remembered that one of the batches was split between two carboys (10 gallons) And that one half of the batch was perfect and the other half had this flavour. Does this make any sense regarding the carboy?!

Well I have to say that looks like the end of search. If you processed post fermentor, both batches identically, which are identical worts, with identical hopping and identical preferment handling, then the only logical conclusion is that the fermentor is the single difference.

Edit: And identical yeast in both, and identical temp during ferment for both, etc
 
Well I have to say that looks like the end of search. If you processed post fermentor, both batches identically, which are identical worts, with identical hopping and identical preferment handling, then the only logical conclusion is that the fermentor is the single difference.

Edit: And identical yeast in both, and identical temp during ferment for both, etc

Yep I agree! All were handled the same. Thanks!!!
 
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