Topless or not?

[DylansDad]

Dumb question that I thought I saw answered earlier but I didn't take note of the answer nor did I find the thread now.

While boiling do you keep the top on the kettle or leave it off?

Thanks,
Dave
Cheers!

 

[chefmike]

leave it off... you are trying to get stuff out, not keep it in... there is some science behind it. But it is late. the DMS? yes, to vaporize those cheeky bastidges!

 

[maztec]

If you can't maintain a boil temp without lid on, then partial lid works - but better yet, buy an insulator to wrap around the container so you get less heat loss.

 

[The Pol]

Is it extract? If so, probably wont matter much.

If it is AG, keep the lid as far off as you can so that the DMS does not condense and drip back in.

 

[schweaty]

Yep, leave the lid/cover off of the boil kettle. The biggest thing is to not let any of the condenstaion fallback in the boiling wort. You want the vapors to escape from the boil kettle, not stay inside. As chefmike said, leaving the cover on the boil can cause DMS (Dimethyl Sulfides) that cause a vegetable like off flavor.

 

[Kronin]

the DMS? yes, to vaporize those cheeky bastidges!

don't you mean those farging bastidges! ?

 

[The Pol]

Sooo, if you use late addition extract brewing... is DMS an issue there? I mean you arent doing a long vigorous boil of the wort, so the SMM isnt removed and DMS isnt driven off?

Isnt extract already boiled?

 

[schweaty]

Isnt extract already boiled?

Good question.
Did a quick search or two and read that malt extract is made using an evaporator that uses high heat from steam to evaporate the water. So if DMS is removed by vaporization I guess it would depend on how long it takes for the extract to cool?

According to Palmer when a malt is roasted/toasted the SMM (S-methyl-methionine) is reduced before hand and DMS is not created in the boil. So I guess it might depend on what kind of extract it is then as well? I honestly never knew anything about the process of making a malt extract until now.

By the way, I thought you were going camping Pol? Did you get a laptop with a wireless card or something

 

[DylansDad]

Awesome. Thanks guys. I vaguely remember someone saying something like, all the steam coming out is going to keep anything nasty from falling in. However the scientific answers are a good thing know.

Yes, it's extract now. However it's nice to start (or change) habits early.

 

[The Pol]

Good question.
Did a quick search or two and read that malt extract is made using an evaporator that uses high heat from steam to evaporate the water. So if DMS is removed by vaporization I guess it would depend on how long it takes for the extract to cool?

According to Palmer when a malt is roasted/toasted the SMM (S-methyl-methionine) is reduced before hand and DMS is not created in the boil. So I guess it might depend on what kind of extract it is then as well? I honestly never knew anything about the process of making a malt extract until now.

By the way, I thought you were going camping Pol? Did you get a laptop with a wireless card or something

Camping was last week.

 

[Captain_Bigelow]

You can leave it partially on to help you get a rolling boil, then take it off.