beer has a rubbing alcohol smell

cdragoon · 03-11-2010, 01:03 AM

I brewed up my first beer about three weeks ago. I used just a can of muntons light hopped extract and some dextrose, just to see if i could make a beer. I used nottingham yeast, fermented at room temp (about 68 F) and it spent 2 weeks in the primary before it was bottled. I went to try one after about a week in the bottle and i went to take a sip and it had an awful smell of rubbing alcohol. it smelled really good while fermenting and i took a little sample during bottling and it seemed ok. i'm just not sure what went wrong, its kinda disappointing since this is my first batch.

any ideas? could it be the muntons hopped extract?

chrisknight · 03-11-2010, 01:06 AM

Solvent-like
This group of flavors is very similar to the alcohol and ester flavors, but are harsher to the tongue. These flavors often result from a combination of high fermentation temperatures and oxidation. They can also be leached from cheap plastic brewing equipment or if PVC tubing is used as a lautering manifold material. The solvents in some plastics like PVC can be leached by high temperatures.

http://www.howtobrew.com/section4/chapter21-2.html

How did you transfer?

**Edcculus** · 03-11-2010, 01:12 AM

Your timeline isn't terrible, but I'd let it sit in the bottles for another few weeks.

The likely culprit is fusel alcohols, which are usually described as "hot", "rubbing alcohol", or "nail polish remover". The main culprits of fusels are too warm fermentation temperature, and stressed yeast.

1 - what yeast did you use? ( and what size batch). Underpitiching will stress yeast and may cause fusels.

2 - you fermented around 68F. Its likely the actual temp climbed well into the 70's. More importantly, what temperature did you pitch the yeast? Pitching too hot can cause other off flavors, one of them being possible creation of higher alcohols.

I feel like I'm missing something, maybe somebody can chime in. Most importantly, let it sit for another 2 weeks (at least). Its suprising what a little aging can do for a beer.

**Yooper** · 03-11-2010, 01:12 AM

I agree with Chris, but I would ask this: You say the temperature was 68 degrees. Was that room temperature, or the actual fermentation temperature?

The actual fermentation temperature can easily be 8-10 degrees higher inside the fermenter, especially if the yeast was added while the wort was still over 65 degrees. That means that if the room was 68 degrees, it could have easily been 76 degrees (or more) inside the fermenter.

A classic cause of solventy flavors is a low temperature ale yeast like nottingham fermented above 72 degrees.

Edit- and Ed beat me too! But they are both right.

cdragoon · 03-11-2010, 01:35 AM

I'm betting my temperature was too high. The ambient temperature was 68 F so it probably got too warm. I did add ice packs to the top of the fermenter everyday though, but it must have still gotten too hot. Will the harshness diminish in the bottles? Thanks for the help!

jalgayer · 03-11-2010, 11:06 AM

I see that you said "if you add the yeast above 65 degrees" ... All my kits from NB tell me to add the yeast when the wort drop to 78 degrees or under.

Should I be waiting til the temp gets lower, Yoop?

Thanks
Jason

**Edcculus** · 03-11-2010, 12:32 PM

Yes, you should at least wait to pitch until it reaches fermentation temperature. I really like to chill to at least 65 before pitching.

Do you have a wort chiller? If so go pick up a $10 submersible pump from Harbor Freight and whatever hose and connections you need to attach it to your chiller. Chill down to at least 90 with tap/hose water. Fill a bucket or cooler with ice water and put the pump in it. Recirculate the ice water until you get to the desired temp. This method works well for me in the summer. In the fall, I've also been known to chill as much as possible, transfer to the fermenter and stick it outside over night to finish cooling.

Neonsilver · 03-11-2010, 04:46 PM

I would say that it is in part to the dextrose as well. Simple sugars tend to give a hotter alcohol taste that takes more time to mellow.

malkore · 03-12-2010, 11:43 PM

Quote:

Originally Posted by Neonsilver

I would say that it is in part to the dextrose as well. Simple sugars tend to give a hotter alcohol taste that takes more time to mellow.

I was going to say the same...I think its more of those funny 'cidery' or whatever flavors from sugar and a single can of extract (cooper's kits, etc) and the greenness of the beer more than fusels from a hot fermentation.

cdragoon · 03-19-2010, 04:03 AM

just popped a bottle open tonight after two weeks. definitely an improvement over bottling time, its drinkable now. alot of the harsh bite has faded, still a little bit though. i'll stay away from the dextrose in the future