Increasing ABV in the mash?

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cokronk

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Would it be possible for me to do a 2nd mash with wort from the first mash to increase the ABV of a brew?

The recipe has something like 1.052 with a grain bill of 11.25lbs of grain. If I do a 2nd mash with the first running reheated to strike temp and run it through, and mash another 4-5lbs of base grain, could I bring the ABV up a few points to give it an extra % or two of alcohol, or would I be better off using fresh water and boiling it down longer in the keg to get it to the concentration I want?

I was going to pick up some DME and do it that way, but I forgot to get it and along with the LHBS charging an arm and a leg for it, it's more appealing to do it with the grains I already have.
 
What is limiting you from just mashing all of the grain at once? Just the size of your mash tun?
 
What is limiting you from just mashing all of the grain at once? Just the size of your mash tun?

Possibly. The original idea was to use the wort from the first run in mashing the second batch to get the higher gravity without introducing extra water. Would it be just as easy to mash everything at once with the extra water and just boil it down?

At 11.25 lbs, I'm looking at about 7 gallons of water for the boil taking in to account about 2 gallons lost on a 90 minute boil from the recipe, iirc. With 16.25 I'm looking at over 10 gallons for a 5 gallon batch. Would I just boil the wort down to 7 gallons and start the boil countdown at that time?

This is my 2nd AG batch, so I'm probably better off sticking with recipes, but I just can't leave stuff damned well enough alone for my own good. :D Plus, brewing is about experimenting and having fun, right?
 
Possibly. The original idea was to use the wort from the first run in mashing the second batch to get the higher gravity without introducing extra water. Would it be just as easy to mash everything at once with the extra water and just boil it down?

At 11.25 lbs, I'm looking at about 7 gallons of water for the boil taking in to account about 2 gallons lost on a 90 minute boil from the recipe, iirc. With 16.25 I'm looking at over 10 gallons for a 5 gallon batch. Would I just boil the wort down to 7 gallons and start the boil countdown at that time?

This is my 2nd AG batch, so I'm probably better off sticking with recipes, but I just can't leave stuff damned well enough alone for my own good. :D Plus, brewing is about experimenting and having fun, right?


The problem with "remashing" the first runnings is that you can't really do that. The conversion of the starches to sugars happens due to enzymatic activity and the pH. The water "pulls" the sugars out by the property of diffusion. So mashing with wort would not give you more sugars, you'd just have wet grain.

If you want a higher OG, use more grain. It's really that simple.
 
I think the biggest problem you'd face with your idea is water chemistry. As I understand it, conversion of starches to sugar in a mash is a complex enzymatic process that happens best when the solution is within a particular ph range. Having a solution with dissolved sugars (and protiens, etc) would seem to push the ph out of the favorable range. You could always try to dilute it with water, or use salts or acids to bring it back, but thats going to affect the flavor. You might be able to squeek out some additional efficiency

Anyways, I say try it and let us know what happens!
 
I think the OP is saying that he is afraid of having too much liquid in his kettle. Just use less strike water. A thicker mash shouldn't hurt anything in your recipe and will allow you to get the same volume of a higher gravity wort. People do crazy thick mashes for bigger beers all the time.
 
He said he forgot the ME when he was purchasing ingredients.

OP: The problem is, a certain amount of grains only has so much potential sugar in it. The ratio of what we get out to the maximum that can be extracted is how we measure efficiency. Optimistically, you could get 85% efficiency or so, so you are limited to the OG that that will yield. The only way to bump up the ABV is add fermentables, either more grain, as Yooper said, L/DME, or simlpe sugars.

"Remashing" with your first runnings will do nothing as your wort will already be saturated and unable to dissolve any more sugar.
 
I do a 60 min mash in the low 150s and a 60 minute dunk sparge in the mid 160's and have been getting efficiency in the high 80s (87.57% with a 10.5# bill last time). You can maybe try a 120ish degree protein rest to make sure all your enzymes are active. Efficiency is mostly (assuming water is a constant) a matter of time and heat, and since you do not want to increase the heat its really just a matter of time.

The point of a mash is conversion not in essence extraction, thats what the sparge is for. Maybe a thick mash and two thin sparges would increase the efficiency.
 
"Remashing" with your first runnings will do nothing as your wort will already be saturated and unable to dissolve any more sugar.

It can be done, and has been discussed on the boards from time to time. The problem is, efficiency goes down sharply during the second mash, as one might expect. The better option is just a thicker mash with more grain, unless it really isn't possible due to mash tun size limitations. Mashing at 1qt/lb of grain is not at all out of the question; it's commonly done for traditional English beers.
 
I found a boil calculator and propane is plentiful. I have enough grains to do upwards of 20 lbs if I want and boil down to 6-6.5 gallons for a 60 minute boil. That's what I wasn't sure about.

I figure I could get it up to 10% :D. I really don't want to go that high. a nice 7-8% sounds about accurate for what I think of when I think of a nice rich smokey porter.
 
I saw my efficiency increase last week about 10 points to 87% after doing a triple batch sparge and a really thick mash, just to reiterate what others have been suggesting.
 
And just boil off the excess water?

You shouldn't have "excess water". Use 1.25 quarts of water per pound of grain in the mash, and then sparge up to your boil volume. If your boil volume is 7 gallons, stop there.

For example, if you are using 10 pounds of grain, you'd use 12.5 quarts of water in the mash and then sparge up to 7 gallons for the boil. Since you'd probably "lose" 1 gallon of water in the mash, you'd have about 2 gallons of first runnings, so you'd need about 5 gallons of sparge water. For me, if I use 10 pounds of grain, in a 5 gallon batch, I get an OG of 1.060 or so. You may get a different OG, of course, based on your efficiency.

If you are using 15 pounds of grain, you'd still use 1.25 quarts of water per pound of grain. That would be 4.68 gallons (call it 4.75 because then the math is easier). Since you should lose about 1.85 gallons to grain absorption, that should give you nearly 3 gallons of first runnings. You can sparge with 4 gallons to get up to 7 gallons pre boil.

If you're going with 20 pounds of grain, 1.25 quarts of water per pound of grain would give you 6.25 gallons in the mash. The grain should absorb 2.5 gallons or so. That means you can sparge with 3 gallons or so to get to 7 gallons preboil.

The less you sparge, the lower your efficiency may be. But it will save you from boiling for 5 hours!
 
Is it possible to sparge too much in order to hit preboil gravity? My LHBS said not to use too much sparge water, rather just add water to the boil. Why would he say that?
 
because they want to rob you of gravity points and make you buy more grain! (well, probably not, maybe they are just....)
 
My LHBS said not to use too much sparge water, rather just add water to the boil. Why would he say that?

Many brewers believe the first runnings make for a better tasting beer than the second or third (or very late runnings if you fly sparge). So as efficiency goes up, through more sparging, wort quality tends to go down. Some homebrewers have taken to not sparging at all, and sometimes top off water to meet preboil measurements in the event that their strike water calculation was off. Of course, what constitutes "too much" sparge water is completely a function of the brewer and the beer drinker. For some, any sparge is too much, for others, it's when sparging will only bring you minimal sugar additions (and high polyphenol or tannin additions).
 
Mashing again with the first runnings is indeed possible. It's discussed here on HBT and also in Radical Brewing by Randy Mosher. I have never done it, but it was supposedly a technique used in the past to produce a very big beer.
 
Boy, I guess if it works, it works. It just seems very counter-intuitive to me. It seems like, once the water is saturated, you're going to see severe diminishing returns if you try to mash with it. But then again, lots of things seem counter-intuitive to me, and I don't know enough about the biochemical process of conversion to refute any claims to the contrary.
 
It seems like, once the water is saturated, you're going to see severe diminishing returns if you try to mash with it.

You do see highly diminishing returns, as I stated above, but it does work. Mosher gives a quote of this style of mashing being "wasteful of malt and men" (or something like that) due to the long time investment and low efficiency.
 
Is it possible to sparge too much in order to hit preboil gravity? My LHBS said not to use too much sparge water, rather just add water to the boil. Why would he say that?

You can definitely oversparge, especially with a small grainbill. That's not usually an issue with most beers, but with a lower gravity beer with a small amount of grain, you want to be sure to not use more than 1/2 gallon of sparge water per pound of grain, ideally less so that you use no more than a total of 3 quarts of water per pound of grain altogether, mash and sparge.

You do see highly diminishing returns, as I stated above, but it does work. Mosher gives a quote of this style of mashing being "wasteful of malt and men" (or something like that) due to the long time investment and low efficiency.

That's the jist of it. I'm not sure it "works" because of the goal in this case- the goal in this case is simply to have a higher OG. More malt would solve the issue completely, while remashing with more malt and the first runnings wouldn't solve the issue because there would still be the "more malt" added anyway! The whole issue would be solved simply by putting more grain in the mash tun in the first place. That way, the correct pH would not be an issue nor would the extract rate of mashing with wort.
 
The process the OP describes is sometimes called "reiterated mashing," and it does indeed work--though as others have noted, efficiency is less than optimal.

This past fall, I made a wort of about 1.037 (pre-boil) and performed a second mash of equal size in it, netting another 30 points. I don't have my notes with me, but after boiling, my gravity was at least 1.080.

I did it because I am a stovetop BIAB'er, and none of my vessels are big enough to mash 10 lbs of grain at once. Reiterated mashing solved that problem, but I don't think I'll try it again anytime soon. The beer I made in that instance was just too much--ABV too high, crazy mashing protocol, too many additions of spice, orange peel, sugar, oak... I learned that I enjoy brewing simpler beers, and I enjoy drinking smaller beers.

But to the OP, if you want to give reiterated mashing a try, it is at least an interesting experiment. There was a good discussion of it on the 11/22/07 episode of Basic Brewing Radio, as well as in "Radical Brewing."
 
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