My first contaminated batch. Thoughts?

[troutman35]

I brewed a bitters last week. A slight deviation in the recipe from the first time I brewed one. The recipe was:
8 lbs Maris Otter
1/2 lb flaked rye
1/2 lb of Munich
1 oz EKG 60 min
1/2 oz Fuggles at 30 min
1/2 oz Fuggles and EKG at 15
1/2 oz EKG at 5
Strike water 168 for a mash temp of 152 for an hour
Sparge water 185 deg for second running
Safale US-04
OG 1.047

Fermented in my cool brewing cooler at 67 deg

Fermentation started within 12 hours. It wasn't a particularly vigorous fermentation so I took a reading at day 5. It was at 1.020

Was shocked at the nastiness. Looking up off flavors / smells and it was somewhere between grassy / cooked veggies/ or baby vomit. Taste was just putrid.

I have about 150 batches behind me and this was the first really rough brew I made. I've experienced diacetyl before, some cider type problems a long time ago but nothing like this.

I used a spray bottle of starsan on my degassing wand before aeration. Bottle was about 3 months old. Perhaps PH was not low enough anymore?

During the boil I had a bug fly in that I couldn't get out, but was boiled for about 30 minutes.

Everything else was cleaned and then sanitized with a fresh batch of StarSan.

This was my first time using the cool brewing cooler for fermentation and the top of the cooler rested on the airlock. Could have this been a problem.

I soaked my wort chiller in the fresh StarSan before using rather than putting in the boil (I've done this before with no problems.

Gonna let it ride for a while and see what happens. It looks fine. At what point should I dump?

Naturally I will do a very thorough cleaning and sanitize the hell out of everything before my next batch. My hoses are pretty new (only 4 batches with them).

One final note, the Maris is about 14 months old. I tasted it before crushing and was still delicious.

Any thoughts on what may have happened and does this stand a chance? It was the least beer like brew I've ever experienced.

Thanks for any ideas you may have

 

[RM-MN]

Tell us about the fermentation with times and temperatures. It sounds like you fermented low and the yeast went to sleep before they finished cleanup. You may get rid of the off flavor by warming the beer and giving the yeast more time.

 

[troutman35]

Visible fermentation lasted about 3 days . Held temperature at around 67. On day 7 today. I've been putting 2 2 liter frozen bottles of water each day. Just went downstairs and swapped them out with 1 2 liter bottle. The beer looks great. Not going to open the bubbler though

 

[unionrdr]

I have to say it sounds most like DMS (Dimethyl Sulfide). From John Palmers, " How To Brew"-
Like Diacetyl in ales, DMS is common in many light lagers & is considered to be part of the character. DMS is produced in the wort during the boil by the reduction of another compound, S-Methyl-Methionine (SMM), which is itself produced during malting. When a malt is roasted or toasted, the SMM is reduced beforehand & does not manifest as DMS in the wort, which explains why it is more prevalent in pale lagers. In other styles, DMS is a common off-flavor, & can be caused by poor brewing practices or bacterial infection.
DMS is continually produced in the wort while it's hot & usually removed by vaporization during the boil. If the wort is cooled slowly these compounds won't be removed from the wort& will dissolve back in. Thus it's important not to completely cover the brew pot during the boil or allow condensation to drip back into the pot from the lid. The wort should also be cooled quickly after the boil, either by immersion in in an ice bath or using a wort chiller.
When caused by bacterial infection, DMS has a more rancid character, more like cooked cabbage than corn. It is usually the result of poor sanitation. Repitching the yeast from an infected batch of beer will perpetuate the problem.
In DRAFT magazine, it's described as "...Evocative of creamed corn, cabbage, tomatoes & other vegetables. DMS is derived from malt, can be detected in the wort, & is reduced by a vigorous boil."
But, here again, in an uncovered kettle!

 

[troutman35]

Yep, I never cover the pot during the boil and the wort was chilled in about 30 minutes with a chiller. The off flavor description is close for sure. Perhaps bacterial. I had a good boil going. I lose 1 1/2 gallons during the hour in my Megapot.

I'll be shocked and awestruck if this is cleaned up by the yeast. I guess I never realized just how off an off flavor can be

 

[unionrdr]

If your boil-off rate is 1 1/2 gallons/hour, you need to dial back your flame! You'd save on gas too. I've found that only a gently rolling boil is needed, after the hot break. If it is indeed bacterial, old grains can also be suspect. They can live on old grains, as I've read here & there since I've been here.

 

[flars]

If your boil-off rate is 1 1/2 gallons/hour, you need to dial back your flame! You'd save on gas too. I've found that only a gently rolling boil is needed, after the hot break. If it is indeed bacterial, old grains can also be suspect. They can live on old grains, as I've read here & there since I've been here.

Is there grain dust from the milling anywhere near where you ferment or store brewing equipment?

 

[unionrdr]

If you're referring to me, no. My grain mill is mounted on a wood base with rubber feet that fit it snugly to the top of my Lowe's 5 gallon bucket. So no dust anywhere, it all stays in the bucket.

 

[troutman35]

Brewed outdoors. I did crush the grain on the deck where I was brewing. Brushed up any dust before brewing

 

[troutman35]

So I let this ride for a couple months. Had the day off yesterday, so I brought this up from the basement. After 2 months, it actually cleaned up very nicely. Bottled it up and will see how it tastes in a few weeks after carbonating. Very surprised that the taste and aroma cleaned up as well as it did.

 

[skraeling]

It sounds like you fermented low and the yeast went to sleep before they finished cleanup.

59-68°F is the temp range for that yeast so i disagree. Unless i misunderstood and you meant gravity?

 

[dallasdb]

My initial thought was DMS.

To me DMS tastes like drinking creamed corn.

In any case, if you have a pesky person constantly asking for homebrew and you want them to stop... give them a six pack of this!

 

[troutman35]

Heh heh. Nah, I like to share my better ones to spread the gospel. And most people I know drink Bud or Busch Light. I always hear "You like that dark heavy stuff". Was pleasantly surprised that I think this will end up drinkable when I tasted it at bottling time. Time will tell

 

[dallasdb]

Pet peeve is when people say they don't like "dark beer." They don't understand color doesn't dictate taste.

 

[RM-MN]

59-68°F is the temp range for that yeast so i disagree. Unless i misunderstood and you meant gravity?

Sometimes the yeast will prefer to be warmed as the fermentatation slows down. When doing lagers, this warming is called a diacetyl rest. We don't use that term for ales but in this case it must have been needed as letting the beer sit for a couple months cleaned it up. Had the off flavor been DMS it would not have cleaned up.

 

[troutman35]

Thanks RM-MN. Beer had no visible signs of infection. I read elsewhere in the forum that DMS doesn't clean up. Glad I did not dump it!