Splitting a partial mash brew over 2 days

[ChessRockwell]

So I'm not completely new at this, I've done a couple all grain batches when I had more time, but this will actually be my first partial mash. My issue is time, I only have a couple hours at the end of each day and need to get this done fairly soon as I've already got the grains crushed and ready to go. I'm going to be mashing 2lbs 2-row, 6oz aromatic, and 1.5lbs wheat for a tripel, so I think I'll need a longer mash (maybe 75-90min?) to make sure and get all I can out of the wheat. I just can't see fitting the 90 min. mash plus a 60 min. boil, cooling time, etc. into one night.

My question is: Can I do the mash, sparge, and save what I get in the fridge for a day or two and then do the boil with extract and hop additions another night? I don't see infection being an issue as I'm going to be boiling it all for an hour anyway, but are there any other issues I might not be seeing? Anyone else done this?

Thanks in advance for any input!

 

[jotakah]

I wouldn't put it right into the fridge. After you sparge, bring the whole thing up to a boil for at least a minute, that will halt any & all enzyme activity as well as kill any & all possible bacteria. Then I'd store it covered in the same pot you just boiled it in (and that you will boil it again in in 24-48hrs).

It's not ideal, and I'm sure others will (correctly) say that this is a bad idea, but I think I'm also semi-correct

 

[House12]

Sounds like a great idea to me. It's no different than just using LME, really.

The only thing to keep in mind is prolonged enzyme activity. You'll want to bring it above mashout temperatures for sure to preserve the profile of your fermentable sugars. And you really would be wise to bring the collected wort to a boil before storing it also.

 

[ChessRockwell]

Good points about the enzyme activity. I think I'll try to do the mash on Friday night, bring it to a boil and leave covered overnight, and do the rest of the brew Saturday when I can get to it. Not ideal, but should work... thanks!

 

[Revvy]

I wouldn't.

You're forgetting that as soon as the wort drops below 130 degrees you open yourself up to lactobasiillus formation. You will be making in essence a sourmash. Then you'll be boiling said sourmash the next day.

If you want to do something like this you need to do what no-chill brewers do, and dump your wart into a sealable vessel where a vaccuum will form as it cools, like an aquatainer. That will hopefully prevent any souring to form until you boil it.

The other option is what many folks do and do an overnight mash where you keep the mash vessel above that temp overnight.

 

[ChessRockwell]

Hmmm... maybe I will rethink. If this was one of my experimental smaller batches I might be willing to risk it, but I *really* want this one to turn out good. Looks like I'll have to come up with a way to talk the wife into letting me use up a whole sunny weekend day brewing.
Thanks Rev!

 

[House12]

When you take the small size of your intended partial mash into account, I don't think a pre-boiled wort stored at refrigeration temps overnight would be a sour mash. Lactobacillus wants to be at about 95-120 degrees. Not 34-40. Boiling the wort before storing, rapidly cooling the wort, and storing the wort at refrigeration temperature will all help to minimize those ill effects.

A sour mash typically involves mashing malt, getting the temperature around 120, and then introducing lacto. by adding in new unmashed malt (since the mash temps above 135 killed the lacto on the mashed grains already) and then keeping it at this incubating temperature to develop the lactic acid. This is much different from mashing, boiling wort, cooling it down, and storing it at refrigeration temperatures for a day.

Having said all that, Revvy's point is certainly worth noting.
I do not personally think the risk of lacto. problems is worth worrying about too much for what you planned on doing (partial mash, boil, cool, store in the fridge), but any length of time between mash and boil and between boil and yeast-pitching always does increase certain risks.

The other thing to keep in mind is that this two-day process will actually take up more of your time in the long run. Having to mash, boil, cool, then store your wort definitely makes for a longer mash time than just your 60-90 minute mash. Then bringing refrigerated wort to a boil will add more time to your brew day compared to boiling from mash temperatures.

 

[jotakah]

Having said all that, Revvy's point is certainly worth noting.
I do not personally think the risk of lacto. problems is worth worrying about too much for what you planned on doing (partial mash, boil, cool, store in the fridge), but any length of time between mash and boil and between boil and yeast-pitching always does increase certain risks.

Agree. Also, lactobacteria aren't ninjas... they can't climb up under lids and stuff, at least not easily. If the pot is sterile from bringing it up to a boil, and you lid it then.... and it's only in the fridge overnight... I realllllllllly don't think it'll turn into a sour mash. Anything is "possible" but I would consider it unlikely.

But, the only way to know for sure is to do it! Try it, let us know who was right as you post over a delicious pint of your 2-day brew

 

[Griff777]

I have done it a couple ways with no ill effects. One is to do a mashout at 169, either before sparging, or take the collected wort and bring it up to 170to stop enzyme activity. If you have time, continue up to boiling and then turn heat off, cover and boil the next morning or day.

My last batch, I mashed out, collected wort in ale pail(6.5 gallons) and boiled and completed the next morning. Of course I had the lid on the ale pail overnight. I like mashing indoors at night and boiling outdoors the next day.

I use about 1.25 quarts per pound for infusion mash,then after conversion slowly add enough boiling water while stirring to bring up to mashout(168-170) wait ten minutes and begin vorlaufing.

One advantage of mashing the night before is you don't rush the sparge. You drain real slow and relax.

 

[ChessRockwell]

A lot of good info here! What I end up doing will mostly depend on my schedule, who knows I might call in sick to work on Friday and do the whole thing (hey it's the day after my birthday they should understand). We'll have to see what time allows...