Size limitations (how much can I mash in this?)

[wolfie7873]

Been making 2.5 gallon batches for a while now, but was hoping to make a full 5 gallons and split it for some exbeerimentation. Can I fit 14.5# of grain and requisite amount of water into a 5 gallon cooler mash tun? Obviously, I could try, but if I fail, I'd have a mess and no easy way out. Anyone have experience?

 

[jmcnamara]

can't say for sure, but I do BIAB and my mash tun / kettle is only 5 gallons. At 1.25 qts/lb, i've maxed out at about 12 lbs or so of grain.
The lid didn't even sit properly on it with that much, and i'm sure the temperature was a bit uneven throughout, but it worked.
I've since tried to stick around 10 lbs. a little extract to supplement things is also a possibility if you can't quite get enough in there

 

[oliver]

scroll down to the 3rd calculator on this site... "Can I Mash it?" http://www.rackers.org/calcs.shtml

14.5# grain at a mash thickness of 1.25 = This mash will take up 5.69 gallons of space.

 

[jmcnamara]

haha, never watched the show, but I got a bob the builder vibe from your post.

"Can we brew it?"
"YES WE CAN!!!"

 

[oliver]

thread hijacking,

 

[wolfie7873]

Ha!

Looks like a late addition of lactose was being counted in the weight of my grain bill. Turns out I have only 13.5# of grain, which at 1.25 qts/lb is 5.28 gallons total. Since a 5 gal cooler holds 5.5 gallons, I can make this work. Barely. Whew!

For any interested, this is going to be a triple chocolate stout with half racked onto montmorency cherries. <crosses fingers>

 

[newmanwell]

FWIW: I had 11lbs of grain in my mash tun last brew session and it topped off a little under the 5 gallon mark (10 gallon tun). I was at a 1.31 ratio. So I think you'll be able to do it but maybe consider a slightly thicker mash (1.15-1.20).

 

[Nosybear]

Move the lactose over into the "other ingredients" area - it's not a fermentable, nor does it get mashed.

 

[jmcnamara]

does the other ingredients section account for gravity, color, etc. of the ingredient (when applicable or known)?

 

[wolfie7873]

If you leave it as a fermentable and don't check 'late addition' its gravity contribution affects the hop utilization rate and thus IBU calculation, so there's something to it.

 

[Head First]

Just a thought wolfie your grain bed will be tall and not very wide. Need to be careful lautering I would guess.
Brew On!

 

[wolfie7873]

Everything fit (barely) and it was a successful brew day. The tall grain bed led to a shorter recirculation, but a longer lauter and higher-than-expected effciency so I was happy with that. I got more activity on facebook about this particular brewday than any other. I wonder if my friends are chocolate fiends.

Can't say I blame them. The wort tasted like hot cococa.

 

[wolfie7873]

Adding for posterity.

The completely full tun and the extremely slow lauter led to what I believe is an over-conversion. I was pleased to get a slightly higher starting gravity, but it's finishing way too low for what I wanted, and all I can think is that it was still converting during the lauter and because the tun was so full, I couldn't add enough hot water to stop. If I do this again, I'll drain the bed as fast as I can without it getting stuck, add 180 degree water, stir, recirc and hopefully get what I intended.

 

[newmanwell]

Also in a thick mash the enzymes are more active. In other words there is the same amount of enzymes in the mash but since they are less thinned out it is easier for them to "chop away" at the starches.

 

[Head First]

Adding for posterity.

The completely full tun and the extremely slow lauter led to what I believe is an over-conversion. I was pleased to get a slightly higher starting gravity, but it's finishing way too low for what I wanted, and all I can think is that it was still converting during the lauter and because the tun was so full, I couldn't add enough hot water to stop. If I do this again, I'll drain the bed as fast as I can without it getting stuck, add 180 degree water, stir, recirc and hopefully get what I intended.

Don't forget to raise the starting mash temp to at least 156 if you want more left.