Need some help: Off flavors and a string of bad batches

[ericwatkins_utk]

Just as it says, I'm on a string of off flavored, bad batches. It really started back in about March with a batch of Dunkel. The dunkel was kegged and and on first draught, I immediately smelled a plastic like aroma from the glass and the same taste followed. I'm not really good with pinpointed which "off flavor" it is but it could have been band-aid like or maybe just oxidized. Plastic is definitly the charastic that comes to mind.

Since then I've brewed 5 batches. Most have turned out ok, but nothing spectacular. My most recent batch was a pumpkin ale and I just popped open the bottle and got the same plastic like taste and smell. I sampled the beer on bottling day about a week and a half ago and the flavor and smell was definitly not there. The only thing the beer has come in contact with since would have been the siphon, bucket, and bottling spigot.

I thought maybe it is equipment contamination, but that doesn't really make since because it appeared in a kegged batch and a bottle batch with the siphon being the only common element. Just looking for help / suggestions??

 

[tjsullivan1]

So you've fermented in different vessels? What about yeast strains or dry vs. active? Temperature while fermenting? Is your brew pot REALLY clean?

 

[Yooper]

Maybe your water source changed, and starting using chloramines? It definitely sounds like a chlorine/chloramine issue here.

 

[ericwatkins_utk]

Just a little more information, both of these batches were fermented a little warm, but nothing extremely high ( 74 degs). I used Danstar Munich for the Dunkel and WLP 002 for the pumpkin. Pumpkin ale was in a primary for 2.5 weeks, and in a secondary for 2 weeks. Sanitation habits are using oxyclean free to remove debris and using Starsan to sanitize afterwards. Bottles were run through a high heat wash twice in the dishwasher, then soaked in Starsan to remove all doubt.

 

[ericwatkins_utk]

Yooper - Each bad batch was brewed with a different water source. The dunkel was a store bought spring water and the Pumpkin was fresh from the Flowing Wells Spring we have rolling out the the hill down the road.

 

[Yooper]

Yooper - Each bad batch was brewed with a different water source. The dunkel was a store bought spring water and the Pumpkin was fresh from the Flowing Wells Spring we have rolling out the the hill down the road.

Then the next likely problem would be fermentation temperatures and/or infection.

I'd try bleach bombing all glass, and throwing away all plastic. I'd buy reverse osmosis water for one batch, and use a clean neutral yeast and keep it under 70 degrees. That should solve the problem entirely, and then you could change one variable (trying different water or a different yeast strain, not raising the temperature!) in each batch.

 

[ericwatkins_utk]

I always get nervous using bleach, but I think you may be on to something. As far as plastic, I've got an autosiphon that is close to two years old and is probably due for discard. I replace tubing about every 4-5 batches. I am using the same bottling bucket that I've had for 2+ years. I never use abrasives on it and always wash it with mild detergent after use and then rinse with water and soak in starsan prior to use. Replacing it still may be a good idea.

 

[Surly]

I also have difficulty identifying off flavors as well. I had the same string of issues. I then looked at the temperature of my sparge water. I had been sparging above 170F and in some cases, (winter brewing) a lot higher than 170F.

Maybe examine temperature control both in the brewing process as well as fermentation cycles.

 

[ericwatkins_utk]

Definitely going to chunk the plastic, but I'm leaning towards high fermentation temperatures. I have a temperatured controlled chamber, but didn't use it either time I've had the issue because I had a lager in the chamber. Have brewed about 4 lagers in the past year (55 deg) which have all been very good.

 

[dnslater]

Definitely going to chunk the plastic, but I'm leaning towards high fermentation temperatures. I have a temperatured controlled chamber, but didn't use it either time I've had the issue because I had a lager in the chamber. Have brewed about 4 lagers in the past year (55 deg) which have all been very good.

So each of the 4 lagers did not have the off flavor? This would definitely seem to point to fermentation temperatures. Remember, fermentation often causes the wort to be several degrees higher than ambient room temperature, so your wort might have been in the high 70's.