Mashing with higher grain to liquid ratio.

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Bobbeer

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I am limited in space and cannot heat a ten gallon pot on our stove. If I brew whole grain in a bag, is it possible to cut the mash water volume significantly in the mash kettle, mash my grains, boil, and then add 50% water to bring up the fermenting volume to 5 gallons?

The reason I ask this is that when using extract, I boil 2.5 gallons on the stove and then after boil, I add clean water to come up with a 5 gallon batch.

I would like to try whole grain, but have no room, nor stove for the typical 10 gallon brew pot to mash the 6.5 gallon starting volume and wondered if it was possible to mash and boil a concentrated 3.5 or 3 gallon mash and then dilute to 5 gallons before fermenting.

Thanks everyone for your thoughts.
 

Dland

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With grain brewing, you'll need enough water for grain to be in a slurry. If I understand you correctly, what you propose would end up more like a paste, and would not work that well.

I think the best approach might be to scale back the recipe to volume your pot & stove can handle. There are plenty of brewers on this forum that make smaller batches of beer, nothing wrong with it (except you have less beer).
 

RM-MN

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The reason I ask this is that when using extract, I boil 2.5 gallons on the stove and then after boil, I add clean water to come up with a 5 gallon batch.

By making the mash too thick you will have problems with getting the grains mixed into the water and your mash efficiency will be low because of that. Making a concentrated wort will require more grains and that will lower your mash efficiency more yet so when you add the water to dilute it you just won't have a high enough amount of sugars to get the desired OG. Making a smaller batch will help and then dunking the grains in water when the mash is over will let you extract more of the sugars (batch sparging is the term to use for this) which you add to the wort you have in the kettle to get a larger volume. This then will bring your efficiency back up.
 

doug293cz

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I ran a scenario using my Mash and Lauter Simulator and came up with the following:

To be viable, you would need to do at least a single dunk sparge of the grain bag after the initial drain and squeeze. The sparge can be done in a 5 gal bucket of room temp water - no need to heat the sparge water.

Here are the specific constraints and parameters used for the simulation:
Max mash volume: 3.5 gal​
Min strike water to grain ratio: 1.0 qt/lb​
Max pre-boil volume: 3.5 gal​
Boil-off volume: 0.25 gal​
Grain absorption after both initial and sparge drains: 0.08 gal/lb (requires squeezing after both drains)​
Grain bill: 10 lb​
Conversion efficiency: 100% (all available starch converted to sugar & dextrins)​
Trub & hop absorption loss: 0.1 gal​
The results are:
Total brewing water: 4.3 gal​
Strike volume: 2.55 gal​
Mash volume: 3.4 gal​
Mash thickness: 1.02 qt/lb​
Sparge volume: 1.75 gal​
Pre-boil volume: 3.5 gal​
Post-boil volume: 3.25 gal​
Post-boil SG: 1.087 - 1.088​
Mash & lauter efficiency: 80.5%​
Volume to fermenter: 3.15 gal​
OG after dilution to 5.0 gal: 1.055​

In order to achieve the above, you have to get 100% conversion of starches, and many brewers do not achieve this, mostly due to the crush being too coarse. Lower conversion efficiency will lower mash efficiency, and the resulting OG will be lower.

The proper way to run the sparge is to drain and squeeze the bag after the mash is complete, place the bag in a bucket with the sparge water, stir the grains for about 5 minutes, then drain and squeeze again.

Edit: If you want to limit the max mash thickness to 1.25 qt/lb, then the max grain bill drops to 8.9 lb, and the OG after dilution becomes 1.050 - 1.051.

Brew on :mug:
 
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Red over White

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Stop thinking everything has to take place in one vessel. You can brew on the stove in 2 vessels, 3 vessels if you wanted. Imagine starting half of one high in alpha and running it into the next for beta to chew on it for fermentability. Think about it as a gift and not a hindrance.

I don't recommend dilution ratios over high 30's for flavor reasons. Start at 65% wort and 35% water into the fermenter for total volume. You can absolutely make incredible beer different than anyone else does, very simply.
 

jcfontario

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I also mash and boil in a smaller 3 gallon pot. I have thought about mashing and boiling in 2 vessels to do an all grain, but have yet to try this since it feels like more work monitoring two temperatures, double the number of hops additions etc. Last year I did a high grain mash in a bag at about 0.95 qt/lb and missed by OG by a mile when I topped it up to 5 gallons. It was supposed by 1.057 and I only got to 1.041, so I had to add lots of DME to get it even in the right ballpark, so my efficiency was very poor.

Now my solution is to have the grain as half of my fermentables in the 2.5 gallon mash (that way I can mash at 1.5 to 2.0qt/lb) , and then add the other half of the fermentables as LME or DME at the end of the boil. I add all of my hops to the boil, which means it is probably at double the concentration before the dilution to 5 gallons, so my hops efficiency may be a little low. After a number of batches, I have found that this approach works well and I am having no trouble hitting my OG targets. It is a little less flexible than all grain, but it works.
 

wetmk

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I would like to try whole grain, but have no room, nor stove for the typical 10 gallon brew pot to mash the 6.5 gallon starting volume and wondered if it was possible to mash and boil a concentrated 3.5 or 3 gallon mash and then dilute to 5 gallons before fermenting.

Look into partial mash.
 

IslandLizard

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Stop thinking everything has to take place in one vessel. You can brew on the stove in 2 vessels, 3 vessels if you wanted. Imagine starting half of one high in alpha and running it into the next for beta to chew on it for fermentability. Think about it as a gift and not a hindrance.
That ^

Split your volumes, be inventive.
You may need some spare buckets to temporary store wort in until you can combine.

You can also mash in a beverage cooler. Mashing at 1.5 qts of water / lb of grist is a good ratio, easy to stir, excellent conversion.
Then lauter by scooping the mash into your BIAB bag placed inside your kettle. Don't overfill it, and keep refilling until your kettle has enough wort.
After lautering (draining or straining), batch sparge the grist, at least once. Or better, twice by splitting the sparge water into equal halves (or thereabout).
 
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homebrudoc

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Nothing wrong with extract brewing. Just had a great Munich Dunkel last week that was an extract beer
homebrudoc
 

InspectorJon

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I used @doug293cz ’s method for a big stout last year. My research landed me at 1 qt/lb as being the thickest wort advisable. I maxed my brew/mash kettle out with that. I lifted and drained the bag and then did a batch spare with the remaining water required for the recipe in a separate vessel and combined the two water volumes together. The sparge step will really up your efficiency rather than just adding water to your first runnings.

I then did a second sparge with a 1/2 gallon of water and as third runnings I got a couple quarts of starter wort for free. I store that in plastic soda bottles in the freezer until I need it.
 
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