Mash Water Volumes

I'm thinking of including a mash out on my next batch, a cream ale, which has a small enough grain bill to use my fly sparge setup.

My recipe which includes 10.75# of grain comes out to:

Mash in @ 1.25 qt/lb: 13.13 qts at 174.3
Mash out @ 1.75 qt/lb: 5.25 qts at 197.7

After some calculations, I realized this won't fit in a 5 gallon cooler because it requires about 5.4 gallons of space. The amount of water I can fit is about 16.34 qts. I played around and here the options I came up with:

Drop the mash in down:
Mash in @ 1.05 qt/lb: 11.03 qts at 176.9
Mash out @ 1.75 qt/lb: 5.25 qts at 197.7

Drop both down:
Mash in @ 1.15 qt/lb: 12.08 qts at 175.6
Mash out @ 1.65 qt/lb: 4.20 qts at 202.7

Thoughts? Or should I just stick with no mash out?

I plugged it into my spreadsheet, and though my volumes and temps dont match yours, Id say do the last one... 1.15qt/lb mash in.

Pol

These are numbers from BeerSmith so I'm not sure exactly what calculations he's using.

Yah my volumes were close, but the temps were about 6-10 degrees different. Keep in mind... a complete MASH OUT isnt necessary, if you can raise the temps into the 160's you will still reduce the viscosity of the sugars and be able to fit it into your cooler easier.

Pol

I don't quite understand the purpose of a mash out other than stopping the conversion. If that's your reason, why? If you take your first runnings to the kettle and start heating, you stop the conversion right there. I believe getting the first runnings sugars out of the MLT prior to sparging is a good way to increase efficiency.

Bobby_M said:

I don't quite understand the purpose of a mash out other than stopping the conversion. If that's your reason, why? If you take your first runnings to the kettle and start heating, you stop the conversion right there. I believe getting the first runnings sugars out of the MLT prior to sparging is a good way to increase efficiency.

Click to expand...

As Pol touches on above, the higher temp also reduces the viscosity of the mash making lautering a bit easier (more efficient) for fly spargers. For them, the flow must be even and consistent and free. For batch sparging, it is much less of an issue and generally mash outs don't contribute much (except perhaps if you did a really thick mash).

BassBurner said:

I'm thinking of including a mash out on my next batch, a cream ale, which has a small enough grain bill to use my fly sparge setup.

My recipe which includes 10.75# of grain comes out to:

Mash in @ 1.25 qt/lb: 13.13 qts at 174.3
Mash out @ 1.75 qt/lb: 5.25 qts at 197.7

Click to expand...

There's a slight arithmetic aberration in your calculations.
The mash out at 1.75 qt/lb with 10.75 lbs grain would be 5.75 gallons, not 5.25 qts.

I have a 5g cooler, and most of my brews use between 10 to 11.5 lbs grain.
I always do a mash out and have plenty of room to spare.
I use about 1 qt/lb for the mash water, and 1g ~ 200 degree water for the mash out, and there's plenty of room. I've even managed a mash out with 13 lbs grain (but that was getting a bit tight).
I prefer a thicker mash than the 1.25 qt/lb as it gives me a more dextrinous wort (which I prefer).
When I started mashing out, I got an increase in efficiency from 75% to 85%

Hope this helps.

-a.

I'm not sure of the exact calculations going on behind the scene, but I think the point is that the 1.75qt/lb is not for the mash out water alone. It's the amount of mash-out water to get the mash up to 1.75 from its starting point of 1.25qt/lb.