Tracking down phenolic off flavor

[BaldApe]

Hi all,

I just kegged my Mild a couple of days ago, and there is a powerful band-aid phenolic flavor. There are three conspicuous things I did differently this time, and I'm trying to figure out which was the most likely culprit.

First, I used PBW to clean the kegs and it is possible that I didn't rinse well enough. I wouldn't expect phenols from PBW, but is that possible?

Second, it was the second time I used a new plastic fermenter http://www.usplastic.com/catalog/item.aspx?itemid=23849
The first batch from this ferementer was very good, no off flavor, so I doubt the plastic is the culprit. I used PBW to clean it in a long soak.

Third, I diluted the wort at the end of the boil with 2 gallons of water, direct from a drinking water safe hose. I allowed it to come back to the boil for sanitation, but might have added some chlorine with the water.

I use Star-San, no chlorine sanitizers. The yeast was the second use on WLP023, yeast collected and washed from a previous batch, then stored in a boiled jar in the fridge for about a month.

The phenolic odor is considerable when I vent the keg. I am hoping it is volatile, and will escape if I vent it daily for a while. Otherwise, I'll have to throw out 10 gallons of what should have been good beer.

 

[highgravitybacon]

Hi all,

I just kegged my Mild a couple of days ago, and there is a powerful band-aid phenolic flavor. There are three conspicuous things I did differently this time, and I'm trying to figure out which was the most likely culprit.

First, I used PBW to clean the kegs and it is possible that I didn't rinse well enough. I wouldn't expect phenols from PBW, but is that possible?

Second, it was the second time I used a new plastic fermenter http://www.usplastic.com/catalog/item.aspx?itemid=23849
The first batch from this ferementer was very good, no off flavor, so I doubt the plastic is the culprit. I used PBW to clean it in a long soak.

Third, I diluted the wort at the end of the boil with 2 gallons of water, direct from a drinking water safe hose. I allowed it to come back to the boil for sanitation, but might have added some chlorine with the water.

I use Star-San, no chlorine sanitizers. The yeast was the second use on WLP023, yeast collected and washed from a previous batch, then stored in a boiled jar in the fridge for about a month.

The phenolic odor is considerable when I vent the keg. I am hoping it is volatile, and will escape if I vent it daily for a while. Otherwise, I'll have to throw out 10 gallons of what should have been good beer.

Your tap water, unless it's from some well in a developing nation, probably contains chlorine and or chloramines which will stank up a beer stat.

 

[Kolsch_Meister]

Your tap water, unless it's from some well in a developing nation, probably contains chlorine and or chloramines which will stank up a beer stat.

There are lots of us that are in a developed nation that have well water. I have a well that is in an aquifer that feeds a spring on my neighbor's land, excellent water for brewing...

 

[lunchbox]

Could be poor sanitation or even sparging too hot. I wouldn't think it's the water as you've used the water before, correct?

 

[BaldApe]

Actually, I think I misidentified the off flavor. I'm wondering if the fact that I added water at the end of the boil, then let it warm back up to a boil for sanitation, but did not vigorously boil at that point could have resulted in a large amount of DMS. My wife does not agree that the off flavor is band-aid, and I think she might be right. More like cooked vegetables.

I have added the same water before post-boil, but I figured I'd be safer sanitation-wise to add it while the wort was still hot. Guess that wasn't so brilliant.

 

[LLBeanJ]

Could be DMS, but you wouldn't get it from adding water, whether boiled or not. DMS comes from the grain and a vigorous uncovered boil will drive it off. If you added the water late in the boil, any DMS should've already been effectively dispatched.

 

[bja]

Does it also have an off smell?

 

[jeremy0209]

but might have added some chlorine with the water.

Yes sir. It's my understanding that chlorine is detectable in a concentration as little as a few parts per billion (not million, billion). I won't even rinse my brewing equipment with water from the tap unless I filter out the chlorine first....that's how anal I am about it.