Post #6 made 16 years ago
by crundle
Overnight mashing can be problematic as it can lead to changes in the amount of fermentable sugars in the wort. With a normal mash, we are targeting a mash temp of around 67 degrees for 90 minutes, which will give a certain amount of starches not converted to simple sugars in that amount of time, which gives the beer body.
If we leave it mashing too long, this ratio will be affected, and the beer can be too thin. This is because the enzymes present will continue to work far longer than they should with a 90 minute mash, and they are not being denatured (switched off effectively) by the temperature being raised to above 80 degrees.
I understand the need to brew at various times in spurts, and have been doing it for a while with 3 little ones, study and work all being factors.
What I think is the best practice if you have to split up your brew day is as follows;
Mash your grain and give a mashout, then get the wort boiling. This denatures any enzymes, which will stop starches being converted to simple sugars, preserving the 'body' of your beer. It only just needs to reach boiling.
Then I would insulate the vessel with doonahs and blankets, the more the merrier, to help keep the temperature as high as possible for as long as possible. This is to stave off infection.
At the earliest opportunity, get it back on the boil and proceed as normal, with hop additions, then cube.
Some days I get mine to the boil, then have to leave it while I go to work, so it is only left for about 9 hours, so it is ok in the urn as above. But where it needs to be left longer, maybe a day or so, I cube the wort when it is boiling into a couple of cubes and leave it till I get a chance to boil it again. I have done this many times without an issue.
It is not ideal, but if it means the difference between brewing or not brewing, especially with little ones around, then so be it.
cheers,
Matt
Mash and boil on separate days?
