Boiling with the lid on?

[suffolk]

I can only speak of my way of brewing extract
I have the lid partially on during the boil, otherwise my stove struggles to boil 12 litres
No one has ever said anything about an off taste in my beers.
In AG it might be different matter but I have never tried it

 

[dps51]

I've got a 50ltr boiler fitted with 2 X 2200watt elements. The lid has a hole of about 10" cut out of it. Over that I place a food plate to accelerate bringing up to the boil. Once reached the plate comes off so my boiler is partially covered to prevent excess evaporation; lots condense on the lid and falls back in. What's DMS taste like, cos I'm certain I've never encountered it in my ales.

you can find out what dms is here
http://www.thehomebrewforum.co.uk/glossary.php

I can not say I had it and I leave my lid on

 

[Gunge]

you can find out what dms is here
http://www.thehomebrewforum.co.uk/glossary.php

I can not say I had it and I leave my lid on

I do know what it is, just sayin' that I've never encountered it. But thank you anyway!

 

[MarkBowie]

I'm going to start my AG once my new house is built and I can set up the brew den. What is DMS and why should it occur? Is it something that would condition out?

 

[dad_of_jon]

I can only speak of my way of brewing extract
I have the lid partially on during the boil, otherwise my stove struggles to boil 12 litres
No one has ever said anything about an off taste in my beers.
In AG it might be different matter but I have never tried it

+1

leaving the lid gets the boil started quicker.

 

[Gunge]

I'm going to start my AG once my new house is built and I can set up the brew den. What is DMS and why should it occur? Is it something that would condition out?

DMS= dimethyl sulphide. Smells like corn but (apparently) can be eliminated by boiling with the lid off. I've never encountered a distinct corn smell in my beers, even those which contain a goodly amount of flaked maize!!

 

[chuffer]

I leave the lid on while it's heating toward a boil but as soon as its near boiling it comes off

 

[TheQuokka]

DMS= dimethyl sulphide. Smells like corn but (apparently) can be eliminated by boiling with the lid off. I've never encountered a distinct corn smell in my beers, even those which contain a goodly amount of flaked maize!!

The smell is often described as "creamed corn," which you can easily pick up on a pilsener boil if you are one of the few genetically qualified to smell it. It can be rather unpleasant in some failed brews, though there is not solid evidence that it is due to boiling with the lid on. It is also a rather recent backyard theory as to why the lid should be left off.

Some older reasons for boiling with the lid off are to avoid boil over, so a more vigorous boil may be maintained (improving the break,) to drive off gases produced by water treatment, mash and boil, and to reduce the wort for higher gravity. The theory that it will come to the boil quicker is easily disproven by any high school physics student, or you can do so yourself at home.

I personally like some of the brulosophy stuff despite some rather unscientific methodology at times, but in this case he admits his results are statistically insignificant.

 

[iamthefly]

I've got a 50ltr boiler fitted with 2 X 2200watt elements. The lid has a hole of about 10" cut out of it. Over that I place a food plate to accelerate bringing up to the boil. Once reached the plate comes off so my boiler is partially covered to prevent excess evaporation; lots condense on the lid and falls back in. What's DMS taste like, cos I'm certain I've never encountered it in my ales.

I've heard it's a cooked vegetable flavour.

I suppose the way to do it would be to incrementally reduce the lid opening with each brew until DMS is evident then go back a step. Thereafter adjust if a particular recipe produces more DMS than average, but that's above my pay grade.

 

[IainM]

I can't talk about boiling with the lid on, and I don't think I've ever eaten creamed corn, but I am currently drinking a beer that never boiled properly due to a defective element and for sure 'cooked vegetable' and 'corn' seem like good descriptions. It isn't unpleasant, but certainly unexpectedly savoury.

 

[TheQuokka]

I've heard it's a cooked vegetable flavour.

I suppose the way to do it would be to incrementally reduce the lid opening with each brew until DMS is evident then go back a step. Thereafter adjust if a particular recipe produces more DMS than average, but that's above my pay grade.

A most unscientific and failure prone way to approach the issue. If you have never tasted DMS you are unlikely to recognise it at trace levels. There are also so many other factors, flavours and aromas in play that you are pretty much guaranteeing a number of failed brews.

No one has suggested any credible upsides to leaving the lid on, while there are potentially several to leaving it off - but it's your brew and you're going to drink it.

Edit:

Someone said he is Scottish and wants to save money and you probably will save a bob or two in electricity or gas, so there is one upside to leaving the lid on...

 

[chthon]

There was said here "genetically inclined" to taste DMS. Can it be that I more smell it than taste it? The only brew that I ever had smelling like sulphur (not creamed corn, being from the continent I don't even know what that is), was one that I had been cooling with the lid on. However, that specific smell only developed after a couple of months.

 

[BeerisGOD]

I'll only leave the lid on till I reach boiling point (or close to with my crap stove)

 

[stevey]

I leave the lid off to stop SWMBO moaning about the sticky kitchen floor when it boils over ;-)

 

[chthon]

I am missing something in this thread. Boiling is not only done for the bittering or driving of DMS, but also to concentrate your wort. I suppose that when you make something with an OG of 1.040 that is maybe not needed (although, I do it even for lower original gravities), but when going to higher gravities water is evaporated so that the gravity increases. And for evaporation, you should not boil with the lid on.

 

[fourbob]

An interesting thread. I make stove top AG following Clibit's "have a go...." thread, and I've made about 50 brews so far. They've all been fine, better than any kit beer and in some cases better than a lot of pub beer. Except for brew number 2 where I left the lid on - it tasted of cabbage. (still drank it tho' :whistle:).

My method is pretty rustic, so there are many variables that could have contributed to this particular brew finishing up below par. But I haven't had the problem again, and all my other brews I've left the lid off. So although the brulosophy article is interesting I'd need more proof before risking another batch to the posibility of boiled brassicas. Using a stove top method it would have it's advantages - easier to reach and maintain the boil and (hopefully) reduced levels of steam in the kitchen...

If the lid wasn't the problem, what else could contribute to the off-flavour? are some malts / hops / yeasts more prone to these sorts of things? Pitching temperatures? anything?

 

[IainM]

An interesting thread. I make stove top AG following Clibit's "have a go...." thread, and I've made about 50 brews so far. They've all been fine, better than any kit beer and in some cases better than a lot of pub beer. Except for brew number 2 where I left the lid on - it tasted of cabbage. (still drank it tho' :whistle:).

My method is pretty rustic, so there are many variables that could have contributed to this particular brew finishing up below par. But I haven't had the problem again, and all my other brews I've left the lid off. So although the brulosophy article is interesting I'd need more proof before risking another batch to the posibility of boiled brassicas. Using a stove top method it would have it's advantages - easier to reach and maintain the boil and (hopefully) reduced levels of steam in the kitchen...

If the lid wasn't the problem, what else could contribute to the off-flavour? are some malts / hops / yeasts more prone to these sorts of things? Pitching temperatures? anything?

Boiled cabbage/veg comes from not removing volatile compounds during the boil. It happened to you in the one beer you left the lid on for and no others, it happened to me on the one brew I couldn't get a decent boil with and no others, I've never of anyone describe an off taste like it unless they also had boil issues, and it is well documented in the brewing literature. Seems like an open-shut case to me.

 

[suffolk]

Is this a different case between extract and AG brewing
With Extract the cause of DMS has already passed
Or am I missing something

 

[chthon]

Is this a different case between extract and AG brewing
With Extract the cause of DMS has already passed
Or am I missing something

I suppose so. The extract can be brewed in a normal industrial kettle with vapour ventilation, so that it can get rid of the DMS. Just from quality control issues this will probably be made sure of.

 

[TheQuokka]

If you are only boiling some extract to get proper hop utilisation then it doesn't matter if the lid is on. A partial mash boil probably has a low ratio of base malts so problems would be less prevalent, but I do find the break is much better with the lid off, hence boiling harder.