Help: Secondary mashing with wort

[PorterV]

I’m not sure whether or not my title explains my question too well as I had trouble finding any references to this idea I had. To preface, I want to brew and imperial stout as I have never done one before. However, the recipe I came up with uses far more grains than I can mash at a single time. Originally I planned to mash half the grains, boil the wort down to the appropriate volume, and mash the other grains completely separately before bringing the two worts together.

However

I had the thought of ‘what if I used the wort from the first mash as the mash-water for the second mash?’ Is this a good idea or a bad idea? Obviously I would have to make sure the temperature is appropriate before re-mashing.

So, can I use re-use wort in place of water for mashing?

 

[sibelman]

Seems like it should work, but... I wonder whether increased sparge water would be needed for the "secondary" mash because it'll be so sugary?

Had anyone tried this?

 

[PorterV]

Seems like it should work, but... I wonder whether increased sparge water would be needed for the "secondary" mash because it'll be so sugary?

Had anyone tried this?

That’s a great point that I did not consider. Increased high-temp sparge will be something I will consider if I do this (which I plan to because why not experiment!)

 

[day_trippr]

It's called a "reiterated mash" and it's definitely a thing for those with mash capacity issues...

Cheers!

 

[Hoochin'Fool]

If you don't want to be boiling wort all day, a handy rule-of-thumb is that 3 pounds of DME can replace 4.5 pounds of 2-row in the mash, and you can add it at the end of the boil (and get more bittering with less hops).

 

[PorterV]

It's called a "reiterated mash" and it's definitely a thing for those with mash capacity issues...

Cheers!

Thank you! Good to know this is an established technique. I just didn’t know the name.

 

[BrewnWKopperKat]

can I use re-use wort in place of water for mashing?

Yes.

Had anyone tried this [reiterative mash]?

Yes. It was an OG 90-ish barley wine.

Chris Colby had a good (and free) series of articles at his [former?] web site. The articles can be found in the Internet Archives "Way Back Machine".

/1/ Reiterated Mashing: Theory and Planning (link)​

/2/ Reiterated Mashing: Practical Advice​

/3/ Mjollnir Recipe [example recipe]​

​

@PorterV : I've also done barley wines with 1) a smaller batch with an extended boil , and 2) additional DME.

If I were to make one agin (and had the time), I'd do a smaller batch with an extended boil.

If I were short on time, I'd use additional sugars. The regional online stores that I work with have DME at good prices (Briess DME ($10/3 lb), Muntons DME ($14 / 3 lb), and Brewers Crystals ($3.50/lb)).

 

[BrewnWKopperKat]

I want to brew and imperial stout

What is the OG that is being targeted?

The Grainfather article (link) that was at the top of my search results from @day_trippr 's suggested web seach was for an OG 90-ish barleywine. And, IIRC, to get above OG 90-ish, a 3rd iteration may be necessary. Chris Colby writes somewhere (maybe at the web site, maybe in his Methods of Modern Homebrewing book) about doing a 3rd iteration to get a higher OG (and the 3rd iteration is less efficient).

There may be ways to maximize a "two iteration" mash. For example, mash only what needs to be mashed and steep the other malts in a side pot. But note that the goal for each iteration is to maximize the sugars extracted (and sparging will dilute the wort). And there will be enough sugars left in the spent grains to make an additional small beer.