Topless, or top on?

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When boiling do you use a lid?

  • I always use a lid when boiling

    Votes: 1 2.7%
  • I never use a lid when boiling

    Votes: 29 78.4%
  • I keep the lid on half way when boiling

    Votes: 7 18.9%

  • Total voters
    37

NPi

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Excuse the intentionally sensational title. I recently read that boiling wort with a lid on can have unwanted side effects (DMS?), however till this point I've had no issue. Now I know that's not a good enough excuse not to listen to reason, but I want to hear other people's opinions.

So how about it, topless or top on?
 
Still relatively new to brewing, but my understanding is that the boil process includes some increase of the OG by reducing the volume of water by evaporation. If you have the lid on then most of the water will condense on the lid and drip back into your kettle, thus diluting the beer.
For my last couple of brews I have put the ingredients into Brewfather and got the calculated figures from there. After boiling with the lid off, my figures have been very close.
 
Still relatively new to brewing, but my understanding is that the boil process includes some increase of the OG by reducing the volume of water by evaporation. If you have the lid on then most of the water will condense on the lid and drip back into your kettle, thus diluting the beer.
That is what is commonly thought, but most of the evaporation is driven by the escaping steam, and the amount of steam generated is driven by the power of the heat source.

In the beginning you will have a bit of condensation on the lid, but the lid will also reach a temperature were there will be no evaporation, and the empty space between the liquid and the lid will be filled with steam, and the same amount of steam will escape from the boil.
 
Interesting to see no one uses a lid whilst boiling. Before I learnt of DMS I always had the lid on for a boil. It was the only way to stop the kitchen becoming a sauna. In regards to the reduction in volume I had always reduced by sparge volume and always exceeded or met my targeted ABV. As per the poll, it seems I was in the minority...
 
Lid off when boiling, lid on when cooling.
Never heard of DMS until now so that's something to take note of and in future I will try leaving the lid off for cooling too, but doing 4 or 5 litre batches so it cools pretty quick anyway.
 
With respect to DMS, some tests from Brülosophy (yeah, I know, I know, but nobody else does tests), seem to indicate that
  • modern pilsner/lager malts have much less DMS than in olden days
  • higher kilned malts, like pale ale malt, also have much less DMS
The main test for them was to have shorter boils, which always seem to succeed (Short & Shoddy) without DMS character in their beers.
 
I never have the lid on or half on. Definite risk of a boil-over unless you have massive head clearance. Just like you would never boil peas in a pan with a lid on as it immediately starts frothing up and makes a mess.
 
Lid off when boiling, lid on when cooling.
Never heard of DMS until now so that's something to take note of and in future I will try leaving the lid off for cooling too, but doing 4 or 5 litre batches so it cools pretty quick anyway.
Lid should go on once it gets below 70 deg C is what Joghn Palmer suggests
 
I never have the lid on or half on. Definite risk of a boil-over unless you have massive head clearance. Just like you would never boil peas in a pan with a lid on as it immediately starts frothing up and makes a mess.
This. I often stick the lid on the get it from sparge to boil quicker and on occasion I’ve not checked on it often enough and the recirc arm hole on my lid turns into a hot break fountain!
 
This. I often stick the lid on the get it from sparge to boil quicker and on occasion I’ve not checked on it often enough and the recirc arm hole on my lid turns into a hot break fountain!
I had the same when I first had my all in one but don't use the lid when boiling now for the same reason.
 
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