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How high temp drives off DMS?

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joshesmusica

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OK, well I've got two biab all-grain batches under my belt now. I'm pretty sure they both got DMS. I can get a high boil if I have the lid part way on, so I thought this could possibly be enough space for it to drive off the dms precursors. I did 90 minutes both times, but it obviously wasn't enough. First one was a pale ale, second a pilsner.

So now I'm wondering if I could just plan to boil longer and it would work? I was planning on doing an american wheat tomorrow, I was gonna make sure to not ever have the lid on during the boil. I can get it above 200F without the lid, just thought that I had read that it needs to be a vigorous boil.

I don't have the resources to go buy any other way to heat up the wort. Does anybody have any tricks to help utilize all the heat? Or any advice on what I could do in order to keep going with all-grain?
 
i read up a little more, it seems that most people agree that dms precursors are driven off above 190F, can anybody give any confirmation to that? if so, i think i'll be ok with just leaving the lid off, even if i'm not getting a super vigorous boil.
 
If I'm not mistaken, you also want the action created by the steam bubbles rising to the top of the wort, generated when boiling, in order to scrub out the DMS. Just heating it up would eventually work, but I would wager it's would take a long, long time. A less than vigorous boil would potentially have the a similar problem.

Also boiling is also about concentrating your wort. The slower you boil off the slower your wort is concentrated and the longer it'll take to hit your desired OG.

What is your heat source? Can you insulate your kettle while it's boiling? That would help tremendously.
 
If I'm not mistaken, you also want the action created by the steam bubbles rising to the top of the wort, generated when boiling, in order to scrub out the DMS. Just heating it up would eventually work, but I would wager it's would take a long, long time. A less than vigorous boil would potentially have the a similar problem.

Also boiling is also about concentrating your wort. The slower you boil off the slower your wort is concentrated and the longer it'll take to hit your desired OG.

What is your heat source? Can you insulate your kettle while it's boiling? That would help tremendously.

it's an electric stovetop. what would you recommend to insulate it with? i thought about that route, but didn't know how well it would work.
 
What is your heat source? Insulation (e.g., silverized bubble wrap, neoprene jacket) around the kettle helps to curb heat loss. You can't do that with gas though, it may burn.

I've done full 7 gallon boils on the electric kitchen stove, and had to keep the lid on part way to keep the boil rolling. Otherwise, it was losing the boil each time the element cycled off. With the partial lid, I still boiled off over 1 gallon an hour and never had any DMS isssues. I boiled for 60-90 minutes.

What is your boil off? Are you at a high elevation perhaps?

Can you boil 2 smaller batches side by side? I've done that, boil 5 gallons on one burner and 2-3 on the other. Then combine at the end.

Also, an electric heat stick (1000-1500W) could give you that extra oomph needed.
 
it's an electric stovetop. what would you recommend to insulate it with? i thought about that route, but didn't know how well it would work.

As you are not in the US and most of are, what is available to you for insulation would be a bit of mystery to us. that being said here is what most of us use:

http://www.reflectixinc.com/basepage.asp?Page=Single+Reflective+Insulation&pageIndex=755

Anything that is not going to flake off and end up in your wort, is flexible enough to wrap around the kettle and can be cut with the tools you already have is fine. Since you use electric, even multiple wraps of newsprint would be fine or dampen cardboard until it because flexible. Use duct tape (Gaffer tape to the UK english world) to attach. Try to keep the last 3-5 cm of the pot free of both tape and insulation.

On my 8 gallon (approximately 30L) BIAB pot this made the difference between maybe boiling if I had 6 gallons to start and a vigorous boil even with 7 gallons.

FYI, doing a partial boil does not give a watery taste.
 
What is your heat source? Insulation (e.g., silverized bubble wrap, neoprene jacket) around the kettle helps to curb heat loss. You can't do that with gas though, it may burn.

I've done full 7 gallon boils on the electric kitchen stove, and had to keep the lid on part way to keep the boil rolling. Otherwise, it was losing the boil each time the element cycled off. With the partial lid, I still boiled off over 1 gallon an hour and never had any DMS isssues. I boiled for 60-90 minutes.

What is your boil off? Are you at a high elevation perhaps?

Can you boil 2 smaller batches side by side? I've done that, boil 5 gallons on one burner and 2-3 on the other. Then combine at the end.

Also, an electric heat stick (1000-1500W) could give you that extra oomph needed.

i'm actually only boiling anywhere from 14-17 liters. That's what sucks. It's fine with the extract batches, but I'm really trying to go all-grain so I can start doing experiments like all the awesome people out there doing experiments for us. But that's also the reason why I don't feel like it's anything wrong with fermentation or sanitation or anything like that. this taste has never come up before, i use starsan on everything, and i have a temp controlled ferment chamber.

I did do a side by side boil on the pilsner because i wanted to test fwh vs. 60 min. BUT that test got screwed over by the fact that my kettles were different sizes. one was wider, therefore shallower, so that one boiled off way more. so the one ended up at 1.069 OG when it was estimated to be 1.057!

i'm in a city called Stavanger. My house is probably 6-10 Ft above sea level if i had to guess. 5 min walk and I'm fishing in the ocean.

i don't have the resources to go by a heat stick, as i'm sure they're outrageously priced here. would wrapping a towel around it work just as well as those insulation sources? there's no risk of burning it, as the burner is completely covered by the kettle.
 
As you are not in the US and most of are, what is available to you for insulation would be a bit of mystery to us. that being said here is what most of us use:

http://www.reflectixinc.com/basepage.asp?Page=Single+Reflective+Insulation&pageIndex=755

Anything that is not going to flake off and end up in your wort, is flexible enough to wrap around the kettle and can be cut with the tools you already have is fine. Since you use electric, even multiple wraps of newsprint would be fine or dampen cardboard until it because flexible. Use duct tape (Gaffer tape to the UK english world) to attach. Try to keep the last 3-5 cm of the pot free of both tape and insulation.

On my 8 gallon (approximately 30L) BIAB pot this made the difference between maybe boiling if I had 6 gallons to start and a vigorous boil even with 7 gallons.

FYI, doing a partial boil does not give a watery taste.

i'm actually american, so feel free to use american english. ;)

so would a towel be fine? my pot is 19L and today i was going to be boiling about 17.

what do you mean by the last 3-5 cm the top last or the bottom last?
 
i'm actually american, so feel free to use american english. ;)

so would a towel be fine? my pot is 19L and today i was going to be boiling about 17.

what do you mean by the last 3-5 cm the top last or the bottom last?

3-5 cm from the burner so away from the bottom.

Towel is fine or a cheap fleece throw blanket.
 
No, I mean partial mash. Do your same mash, sparge and boil except on a slightly smaller scale and add extract at the end to reach your OG target. With a smaller boil size you should be able to achieve more vigour.

https://www.homebrewtalk.com/showthread.php?t=75231

ah ok, just checking that's what you meant. that was my step into all-grain. but i'm a stubborn fool and really want to do all-grain. i know extracts can make a very repeatable beer, but I just want to be able to have complete control over every aspect of the brew, so that once I get down the processes and procedures for all-grain biab, i can start doing experiments.
 
You could supplement the heat with an electric immersion heater. This one is 120V, for North American power, but maybe there is a similar 240V model available.

as i've stated already a couple of times, i don't have the resources to do any add-ons to my brewing equipment right now. just trying to find a workaround (if there is one) with what i've got in the house.
 
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Would it be possible for you to do two smaller boils at the same time and combine in the fermenter?

Maybe you have another kettle lying around?
 
Can you boil 2 smaller batches side by side? I've done that, boil 5 gallons on one burner and 2-3 on the other. Then combine at the end.

I did do a side by side boil on the pilsner because i wanted to test fwh vs. 60 min. BUT that test got screwed over by the fact that my kettles were different sizes. one was wider, therefore shallower, so that one boiled off way more. so the one ended up at 1.069 OG when it was estimated to be 1.057!

Would it be possible for you to do two smaller boils at the same time and combine in the fermenter?

Maybe you have another kettle lying around?

i tried that... :confused:
 
If you have the means, the IC-3500 (Watt) induction plate is a great affordable alternative, as long as your kettle is "magnetic" or induction ready.

Countertop "5th" burners are typically low power, topping out at 1000-1500W, probably less than your stove's. Do you happen to know the wattage (output) of your stove's elements?

What is the largest amount of water (wort) you can keep on a rolling boil, with a blanket around the kettle and the lid half off?

Splitting over 2 kettles (and burners) is a very good alternative to boil 2x the volume.

What is your grain brand? source? Is the grain old or stale? Pilsner malts tend to have higher levels of SMM, DMS' precursor.
How do you know it's DMS?

You're at sea level, so 100°C is your boiling temp. It should measure that on the top, in the center of the kettle, and possibly a few degrees lower around the sides. The rolling is needed to disperse the heat throughout the kettle and turn it over while steam drives off DMS. See this article on DMS.
 
i tried that... :confused:

Yeah, tl;dr, just throwing stuff out there.

Well, you should know your boil off rate now... so, boil as much as you can in those two kettles and end up topping off with like, a gallon or something.

That's not going to "water down" your beer. Well, it is, but shouldn't cause any ill effects.
 
I boil on the kitchen stove with the lid partially on to be able to use a lower heat setting to maintain a rolling boil. I wipe the condensate off the under side of the glass lid as it begins to form large droplets. When using pilsen malts the paper towel, used to remove the condensate, will have the strong aroma of cooked corn.

Perhaps part of the problem is the DMS being boiled off in the steam, but reintroduced into your wort with the condensate dripping back in.

I had read about DMS, but never experienced it until my first Hefeweizen.
 
Why not just do smaller batches.

Nothing etched in stone that says it's gotta be 5g

I would do 2.75-3 gallons

You will be doing AG

You will have better control of the process than with an inadequately boiling bigger batch

Rolling boil should be easily obtained

No need for top ups, extract etc.

Seems like the obvious solution covering all issues.

If you are concerned about time -v- volume produced do two at once on different burners. Smaller pot means you can likley use the oven to keep satble mash temps (a hold-warm setting if you have it)

It's win win in my mind.
 
What is your grain brand? source? Is the grain old or stale? Pilsner malts tend to have higher levels of SMM, DMS' precursor.
How do you know it's DMS?

i don't think the grains are old or stale. they're usually either from best malz (german) or from thomas fawcett and sons (english). most of the lhbs products seem pretty fresh. it's the only one in the city, and basically if you show up the day before their next shipment, they're likely to not have what you're looking for.

for the first beer it was pale malts, for the second one it was pilsner malts.
i guess i don't know for sure that it's dms, because i've never actually tasted it. it's just seems to be from all the descriptions i've read about dms. and i've never had it before in any extract or partial mash that i've brewed.
today i've got 48% MO, 37% wheat malt, 7% flaked barley, 4% crystal 40, 4% vienna. think i'm still gonna run into this issue?

grain bill from the pale ale was 84% pale malt, 8% crystal 40, 8% wheat malt.
from the pilsner: 75% pilsner, 17% vienna, 8% cara-pils.
 
Why not just do smaller batches.

Nothing etched in stone that says it's gotta be 5g

I would do 2.75-3 gallons

You will be doing AG

You will have better control of the process than with an inadequately boiling bigger batch

Rolling boil should be easily obtained

No need for top ups, extract etc.

Seems like the obvious solution covering all issues.

If you are concerned about time -v- volume produced do two at once on different burners. Smaller pot means you can likley use the oven to keep satble mash temps (a hold-warm setting if you have it)

It's win win in my mind.

i am doing smaller batches! haha. been doing 9L batches, today was wanting to do a 12L batch.
 
+1^

Brew the largest batch your stove/burner can handle. Nothing wrong with that and you get more variety. Or do 2 or 3 back to back, (mash once though!) or simultaneously if the other burner have the same or nearly same wattage.

For a malt experiment I brewed 4 mini batches of 2 quarts each at the same time in 4 pots. Between mashing, lautering, and sparging I was very busy for a few hours.
 
ok. so it's not the temp that matters to drive off the precursors? but actually that it's a rolling boil? because i read somewhere that they are driven off at or above 190F. I can get mine to about 197 without the lid on.
Now i've even wrapped it in foil first, then a towel. not helping any. (not my wort, i'm just testing with water)
 
Wrap in a lofty towel, then foil on top of that.
Fiberglass insulation is among the best, if handled right. Or an old wetsuit.

You really need to get closer to 210-212°F to call it a rolling boil, at sea level. How big of a volume is that right now?
Did you check the specs of that stove? Wattage for each burner? If they're 1000-1500W it's not going to be enough for 2 gallons. How large is that pot? material? If really large for the volume you boil, there's a lot of heat loss.

I never had problems with DMS when I had the lid on half way. As long as the wort temp is 210-212 and a good boil off takes place it seems to work fine.
 
You need to be able to get a good boil without the lid on. You can have the lid on to help it get hot before it boils, but it needs to be off and you need to be able to get a really good boil going. Some brewers are reporting they can have the lid on and not have DMS, but they might be using different malt than you are.
So, how many liters or gallons can you boil? Just do some tests with water and see what the max is?
197F is not adequate, what are the dimensions of your brewpot? Perhaps a different size (smaller volume, not as tall or wide) pot won't give up as much heat and you'll be able to get a good boil going on your stove.
 
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Wrap in a lofty towel, then foil on top of that.
Fiberglass insulation is among the best, if handled right. Or an old wetsuit.

You really need to get closer to 210-212°F to call it a rolling boil, at sea level. How big of a volume is that right now?
Did you check the specs of that stove? Wattage for each burner? If they're 1000-1500W it's not going to be enough for 2 gallons. How large is that pot? material? If really large for the volume you boil, there's a lot of heat loss.

I never had problems with DMS when I had the lid on half way. As long as the wort temp is 210-212 and a good boil off takes place it seems to work fine.

i don't know how many watts it is. it's old and i don't want to move it to look at the back with the test boil going. but i suppose it's obvious that it's not enough. i've been taking out water now little by little to see how much it can handle. it's a 19L pot, so i guess that could be the issue since it has a ton of overhead space.

so i should wrap the towel first then the foil? for some reason i assumed it should be foil first. i'll switch them to see what happens.
 
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