Keggle Question DMS

[IloveWorts]

So I have an odd off flavor that I think is DMS, Im thinking that its because my boil pot is from a keg that has the top cut off. The only thing is that the top is cut off but there is still a little bit of a lip that hangs over the kettle. My guess is that it catches some of the evaporation and then the DMS drips back into the kettle. The lip is about 2-3 inches around the top.

Would this cause a DMS problem?

 

[myndflyte]

I think if that were the case that a little lip that catches evaporation has enough DMS in it to be perceptible would mean that if you put your face over a boiling brew pot, the amount of DMS would have to be overwhelming.

What is the recipe that you are tasting this in and what were your procedures (brew day, fermentation temps, etc).

 

[IloveWorts]

I think if that were the case that a little lip that catches evaporation has enough DMS in it to be perceptible would mean that if you put your face over a boiling brew pot, the amount of DMS would have to be overwhelming.

What is the recipe that you are tasting this in and what were your procedures (brew day, fermentation temps, etc).

So this flavor is in all of my batches, Ive changed everything I can think of to try and get rid of it or to give me help and nothing so far is apparent. The one recipe ive done multiple times is bee cave pale ale

12 lbs 2 row
.5 cara pils
.5 crystal

cascade and centennial (stored in the freezer)

60 min boil then cooled through chiller then fermented @ 62 for 2 weeks and kegged, purged then on tap. I clean everything very well and Ive had an infection before this does not seem like one at all. CA and US 05 yeasts using pitch calculator and yeast starters.

When I keg the beers I can slightly taste this odd spoony/vegetal taste that me and the guys seriously could not describe properly if one where to pay us. It does really come out when its on tap though, once its on tap the off flavor really comes out.

If anything I feel like it just washes out the other flavors in the beer, the hop aroma and flavor just get muted by this kinda sweet kinda medicine like dullness. Beer is super clear as well and the gravity is always "finished" when I check.

 

[IloveWorts]

I also treat my water with Camden Tablets but I have no clue if its actually working. I add gypsum and use phosphoric acid to lower my ph to 5.2-5.4 in mash, mash at 148-150

 

[dmtaylor]

So I have an odd off flavor that I think is DMS, Im thinking that its because my boil pot is from a keg that has the top cut off. The only thing is that the top is cut off but there is still a little bit of a lip that hangs over the kettle. My guess is that it catches some of the evaporation and then the DMS drips back into the kettle. The lip is about 2-3 inches around the top.

Would this cause a DMS problem?

Yes, it can be a problem. A friend of mine has the same setup and the same problem -- for a long time all his beers had a DMS problem. We discussed it and I advised him to boil super hard to see if the problem would go away. For the past couple of years I haven't noticed the same issue so it must have worked. Boil really really hard, that's my advice.

Good luck.

 

[IloveWorts]

Yes, it can be a problem. A friend of mine has the same setup and the same problem -- for a long time all his beers had a DMS problem. We discussed it and I advised him to boil super hard to see if the problem would go away. For the past couple of years I haven't noticed the same issue so it must have worked. Boil really really hard, that's my advice.

Good luck.

Yeah I think im definitely going to boil harder. Im guessing it has to be a combination of things unfortunately.

 

[Jim311]

My keggle has the same lip and I don't have DMS issues.

 

[jaroporter]

don't worry, absolutely not is your keggle rim the problem here. no chance.
just think of commercial kettles; think how many brewers use cut top keggles.
i got a keggle with just a 100mm opening on it (can use half the leccy and hook up to a 4" vent pipe easily).

if it's DMS then i agree that attempting to boil harder will be a good (the best?) place to start. the only time i ever had it was when i used to use two cheap elements and one broke at the start of the boil. i thought DMS was a myth until that beer. damn it was undrinkable..
hope it works out for ya

 

[myndflyte]

Have you bottled any of these batches and if so, do you get the same off flavor? Because sometimes when off flavors get worse after being on tap, people discover their gas lines got beer in them or even the manifold has some stuff growing in it.

 

[SoCal-Doug]

Couple tidbits about DMS because i'm bored at work and need a break

Some people perceive it as corn or creamed corn. Some people will perceive it as cabbage or asparagus. Oddly enough, DMS is also released by decaying carcasses (i.e. road kill) and is an excellent fly attractant (for those flies that deposit eggs on decaying flesh). So, if you find that flies (and meat eating pollinating type pests) are finding you during brewing, that's why. Some people (including myself) that love corn, cabbage and asparagus, won't find the odor as offending as others might.

It boils/volatizes at about 100F but that temperature will not get it to depart wort in a timely manner. A rolling boil provides agitation and bubbles to carry/exchange DMS to the surface where it can go away into the atmosphere. A common guestimate and rule of thumb is with a hard rolling boil, roughly 40% of the DMS is gone after 30 to 40 minutes. With a 60 minute boil, well over half of the original DMS has gone away. Beyond that, most people can't detect it.

So... No wimpy boiling. Get it rolling and keep it rolling. I have keggles also and even with the maltiest of my pilsner ales and pilsner lagers, I haven't detected (nor has anyone that mooches [oops, I mean shares] my brews detected) DMS. Note on wimpy... I do keep it slightly wimpy until i'm convinced the hot break has completed. Then I kick it's a$$

 

[IloveWorts]

Thanks guys, so ive been looking into the issue more and I believe it was under-pitching. I have an excellent fermentation chamber with both warming and cooling ability with control as well as a filtered air pump to give me good aeration. I think this is why my beers have this odd flavor is from the yeast multiplying and trying to be able to grow to eat all the sugars even though the temperature is good and the oxygen is there.

 

[Scottie61]

Brewed on the last nice outside brew day (in my area), October 22nd, and did a 5 gallon batch of a cream ale (Spotted Cow clone) that I've done several times before, with flaked corn in the recipe. Wonderful fall day outside on the patio, with a small fire in the pit, brewing and carving pumpkins.

But, was my first brew using a converted keg as a boil pot (keggle).

Observations:

• The fermentation had plenty of activity and looked pretty normal;
• The brew didn't clear very well, even with finings;
• Had a weird flavor that didn't show up for previous brews of the same recipe, and the flavor wouldn't mellow after aging in the keg. Tasted to me like a grassy 'young' beer, even after several weeks of aging;
• Was always ludicrously foamy after it was kegged, during dispensing;
• Some of this got consumed, but I ended up throwing it out before it kicked, the first time I've ever thrown out any amount of a batch ( -Sad, as potus would say).

Didn't have a chance to bring a bottle to the brew club to have someone verify DMS, but that's the only thing I can think of for this. Don't think I have any HSA issues, and never had any infections before. My immersion cooler worked quickly, as usual.

Other ideas?

My keggle has a lip on it like most of these do, and I knew not to leave a lid on during the boil. I boiled about like I usually do, just keep it rolling after the hot break is over, but maybe I didn't boil it hard enough given the lip on the keggle? My volumes came out right, as usual.

As an idea, anyone ever use a clamp-on fan to keep the steam moving up and out during the boil?

Weirdest batch I've ever had. Barring any other ideas, next time I'll try boiling the hell out of it.

Thanks for any input!

Scott

 

[dmtaylor]

Hard to say. I'd prefer to taste it myself and diagnose that way. It is difficult over the interwebs. Is DMS possible? Sure. Is DMS your issue? Who knows. Keep in mind, there is corn in the recipe, which can fool people into thinking there's a DMS problem when in fact it might just be the corn that you never noticed before.

 

[mabrungard]

Boil really, really hard??? That isn't my experience. I boil with the kettle mostly covered for most of the boil duration and only have enough heat to make the wort visably roll over. Its nowhere near 'erupting'. I do uncover the kettle for the final 15 minutes and that extra heat loss makes it necessary to increase the heat. I do let it boil with a little more vigor, but still not erupting. I only lose about 10% of my original volume during the boil. Pro systems often lose even less volume.

An important point is that almost every commercial brewing kettle is covered and there is only a small vent stack to bleed off the steam. We homebrewers tend to boil way too hard and too long and that does damage the beer.

 

[dmtaylor]

almost every commercial brewing kettle is covered and there is only a small vent stack to bleed off the steam.

I'm not sure what to believe anymore. I know of at least one brewery (New Glarus) that has a sort of J or U ring to capture any condensation in the blowoff to prevent it from running down into the beer again, for what exact purpose I must confess I do not recall but it sure seems consistent with DMS prevention. Anyone else have other examples? Otherwise maybe I'm full of it again.

 

[Scottie61]

DM,

I agree, when I first tasted it, I was thinking, 'whoa, is that the corn coming through so strong this time?' Other tasters who had liked my last very successful batch definitely noted the difference. None of these folks know about DMS or other flaws, though, so we couldn't do a positive ID. More of a grassy vegetable flavor, to me, rather than corn.

Martin,

Using kettles until now, I've always been more of a gentle boil guy, too, and I've kind of wondered about over boiling myself, and if wort can get altered flavors through scorching? Never been a problem though in over 25 batches, so I have to wonder about the keggle vs kettle thing.

Scott

 

[mabrungard]

It is not damage from scorching. It is damage from the formation of thiobarbituric acid (TBA) that has been proven to be a strong indicator of beer oxidation and damage. TBA causes beer to age more quickly. Look it up, the pro's have been focused on that factor for decades. They actively try to avoid that result.

 

[IloveWorts]

Ok so after making some changes I have to say the flavor I had is completely gone. I really dialed in the amount of yeast i was pitching, took my time re-hydrating it properly with good amounts of water and proper temp. First thing I noticed is how "clean" it tastes. I did an English pale ale and it tastes great going into the keg. Now....I am keg hopping with 2 oz of East Kent and 1 oz of Columbus so I am hoping the hops really give it a nice aroma and taste. So far so good.

 

[IloveWorts]

It is not damage from scorching. It is damage from the formation of thiobarbituric acid (TBA) that has been proven to be a strong indicator of beer oxidation and damage. TBA causes beer to age more quickly. Look it up, the pro's have been focused on that factor for decades. They actively try to avoid that result.

Very interesting. Scary at the same time

 

[Scottie61]

Worts,

Glad you found a solution!

Martin,

Heard of TBA, but I'll have to go look that one up again!

Scott

 

[IloveWorts]

Worts,

Glad you found a solution!

Martin,

Heard of TBA, but I'll have to go look that one up again!

Scott

Hopefully this is one of my last problems ill have to find! Prost!

 

[dmtaylor]

More of a grassy vegetable flavor, to me, rather than corn.

The experts say DMS tastes more like cabbage or pumpkin than corn, actually. So "a grassy vegetable" flavor seems very consistent with this description. Likely DMS.

In past I have also tasted beers with a distinctive celery flavor. I've always wondered if that too is a DMS flavor, and it seems consistent as well. But I'll confess, I'm really not an expert taster quite yet. I'm BJCP Certified but still have more to learn I think.

 

[Scottie61]

Martin,

TBA looks to be a test that tries to predict long-term flavor stability. Not sure that oxidation was my problem, but hey, good research in looking it up.

Scott

 

[Scottie61]

DM,

Well, next time I'll try boiling it harder and see what happens. I did notice that the top of the keggle was relatively cool to the touch during the boil, so was DMS distilling onto the sides of the keg? After all, it's a 15gal container with only 5-7 gallons in it. Hmmm...

Time to add a thermocouple to the top rim of the keg?

Scotter

 

[mabrungard]

TBA looks to be a test that tries to predict long-term flavor stability.

You may not have researched deep enough. TBA has been proven to be THE component that most directly signals a beer's susceptibility to poor stability, which includes the effects of oxidation.

 

[IloveWorts]

You may not have researched deep enough. TBA has been proven to be THE component that most directly signals a beer's susceptibility to poor stability, which includes the effects of oxidation.

Are you saying this might be one of my problems? Going to take a look into this now.

 

[mabrungard]

Are you saying this might be one of my problems?

For anyone that boils their wort long and hard, this is definitely something to be concerned with.

 

[IloveWorts]

Got it, doing a Pale Ale this weekend. Feeling good about this one, going to use a simple grain bill, same yeast with same prep and calculated re hydrated pitch with all the fermentor needs (aeration pump and temp control) and going to do one bittering charge, one 10 minute charge and one lower sized dry hop using some numbers that Mitch Steele mentions in "For the Love of Hops" and hopefully it will come out even more balanced. I will again update on my brew day and the final results.

Will be tasting the previously mentioned kegged english pale ale on how it turned out.