Mash water thumbs rule for mashing in a cooler

[beauvafr]

I am a bit confused about it. I am new to mashing in a cooler (was doing BIAB before, no sparge).

I have 10.7 lbs of grains and I needs 5.5 gal pre-boil. I do only batch sparge and no mashout. In a way to optimize the efficiency, what would be the ideal qty for:

• Mash water
• Sparge water

 

[AnOldUR]

Thinking you meant 5.5 gallons post-boil for a 5 gallon batch?

So, that's 6.5 gallons pre-boil with a gallon of boil-off.

Two equal runnings will be 3.25 gallons each.

Add 1.5 gallon to the first runnings for grain absorbsion to get 4.75 gallons at dough-in.

Sparge with the other 3.25 gallons.

That's about 1.8 qts/lb mash thickness, should be fine.

Did I miss anything?

 

[sloanfamilydsm]

Are you sure that title is in English. Or is it Canadian?

 

[beauvafr]

My recipe call for 4.6 gallons post boil. I adjusted the original 5 gal recipe with a 60% efficiency to make sure I will get the OG.

 

[b555wpd]

I usually start with 1.25 qts per Lb of grain. This is a little lower than people seem to recommend but it allows for more adjustment if you don't hit your correct temperatures the first time around. For a 10 lb grain bill that comes to about 3 gal to start. I usually mash out to 170 with another 2 gal or so, this depends how much boiling water is required to get me from 152 or so to 170. I usually lose about .29 qts per pound of grain.

Once I get my first run off of wort I look at how much I got and sparge with whatever the difference is to 6.5-7 gal. If there is extra in the mash ton when I get to my desired volume I just shut it off rather than have an over full boil kettle.

I would be curious what more experienced brewers think about my system.

 

[djfriesen]

Once I get my first run off of wort I look at how much I got and sparge with whatever the difference is to 6.5-7 gal. If there is extra in the mash ton when I get to my desired volume I just shut it off rather than have an over full boil kettle.

I would be curious what more experienced brewers think about my system.

There shouldn't be any extra in the tun, as that was how you determined your sparge volume. Or am I missing something?

I typically mash in with 1.5-2 qt/lb plus absorption allowances. After draining everything off, I add whatever else I need to hit my preboil volume.

 

[b555wpd]

Usually I don't have extra and if I do it isn't much. I just don't have a very accurate way to measure the volume in my boil kettle. I just use an old racking cane that I have marked out so I sometimes think I need say 3 gal and end up at my target preboil volume with .25-.5 gal left in the mash ton.

The place that I have more trouble with is hitting my mash temperatures. When I add more boiling water to adjust it I end up with a lot more in my mash than I planned and less room for the sparge. I'm not sure why the temps get so far off, I measure the temp and enter the vol of water and grain into beer smith but the temps often come in very low.

 

[wilserbrewer]

Once I get my first run off of wort I look at how much I got and sparge with whatever the difference is to 6.5-7 gal.

This above! It's not all that critical, just mash in with say a bit more than half your batch size, say 60%, or about 4 gallons for a 5 gallon batch, then after collecting your first runnings, measure in your kettle how much more you need to reach your pre boil volume and sparge that amount...very simple if you let it be....

 

[IslandLizard]

Use this calculator (365) or this one (BF).

I use 1.25-1.5 w/g ratio (typically 1.33) and sparge 2x with half the total sparge volume each, works like a charm.

One note about strike temp:
I've found out my strike water in the cooler needs to be 4°F higher than calculated to correct for heat loss during doughing in. The lid is off for 5 minutes while stirring and no calculator accounts for that.

 

[b555wpd]

This above! It's not all that critical, just mash in with say a bit more than half your batch size, say 60%, or about 4 gallons for a 5 gallon batch, then after collecting your first runnings, measure in your kettle how much more you need to reach your pre boil volume and sparge that amount...very simple if you let it be....

This is basically what I do. The difference is that every recipe I have used calls for a mash out at 170 after the hour of say 152 (depending). Then I need to add 2 gallons or so of boiling to get to 170 for the mash out. If I start with 4.5 gal then 2 for mash out and lose 1 to absorption this only leaves a gallon or so for a sparge. If I was low on my strike temp, say 140 and had to add more boiling water to get the correct temp then there is even less.
Do other people not use a mash out? I suppose if the sparge is around 170 it probably wouldn't be necessary but at this point I just follow the instructions. Still only a year into brewing.

 

[gotbags-10]

Probably already doing this but if not then make sure you pre heat your mash tun with hot water for a few min. I have a 10g Rubbermaid and I was always about 4 degrees off (low) when mashing in. I started preheating and then all the beer smith calculations were spot on for me.