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Mash water amount question

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ayrerperformance

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Hey everyone. I read more and more that the more water that you mash with the better efficiency will be. Today I mashed with 2.1 qt to lb and ended up with 62 percent. 90 minute mash, lots of stirring. I'm crushing super fine. Gonna start checking ph, but if I bump the water up how do I not end up with too much wort? Just boil longer?
 
Pounds of grain x 0.13 = Water absorbed by grain (my last batch was 10 lbs, so 1.3 gallons of my mash water was absorbed by the grain)

Boiloff rate = (mine is 1 gal/hour)

Kettle gunk loss when transferring to fermenter = (mine is about 0.5 gallons)

(Boiloff gallons per hour x boil time in hours) + (pounds of grain x 0.13) + kettle gunk loss = amount of water to add to desired batch size.


example
10lbs grain
1 gal boiloff rate
.5 gal kettle gunk loss

(1 gal x 1 hour) + (10 lbs x 0.13 gal absorbed) + 0.5 gal kettle gunk + 5.5 gallon batch =
(1) + (1.3) + 0.5 + 5.5 = 8.3 gallons of water for mashing/sparging.

Then you can decide how thick you want to mash at, say 1.5 qt / lb
10 lbs x 1.5 qt = 15 quarts = 3.75 gallons

Of those 3.75 gallons that you mash in with, you can find out how much you'll get back out by doing 3.75 gal - (10 lbs x 0.13 absorbed)
3.75 gal - 1.3 gal = 2.43 gallons of first runnings.

8.3 total gallons - 3.75 gallons = 4.55 gallons to sparge with.

That's pretty much what I do for calculations. Then I use an app to figure out the temperature of the sparge water.
 
Thank you. I am doing no sparge right now. I see a lot of people talking about 80 percent with no sparge. I suppose the extra gallon or so makes a big difference.
 
Another question. I dump the kettle into the fermenter. So I'm not losing anything there. Is that a bad thing, should I be siphoning?
 
You can mash with full volume, or control the thickness. Either way you shouldn't be getting 60 % efficiency.

To make your life easier, use a calculator for your water volumes and temps. For obvious reasons, I suggest using my own. It's highly flexible and has more features than any other calculator I've seen (beersmith included) but still easy to use. Link in my sig. Click calculators at the top.

Don't worry about your break material in the kettle. It'll be pretty compact after fermentation is complete and it's all crashed out.

Absorption is usually 0.08~ or so with BIAB, NOT 1.25.
 
Hey everyone. I read more and more that the more water that you mash with the better efficiency will be. Today I mashed with 2.1 qt to lb and ended up with 62 percent. 90 minute mash, lots of stirring. I'm crushing super fine. Gonna start checking ph, but if I bump the water up how do I not end up with too much wort? Just boil longer?

At 2.1 quarts per pound, I don't think mash thickness is to blame for the efficiency you got. I'd look for some other culprit in your process.
 
I have been using calculators. This was my best efficiency to date. I'm going to crush even finer next time. I have a real bag coming too instead of using paint strainers. I have a feeling they are not letting the mash thin out enough. A lot of water lays below the bag because it only fits the basket in the kettle.

Priceless, I may have plugged in a wrong number somewhere, but your calculator told me I needed 1.1 gallons more than a couple other calculators did. Maybe it was right but it made me nervous.
 
I just ran the numbers again and your calculator says I'd have 5.75 gallons post boil which is the same as what it said yesterday. That doesn't sound bad. Somehow the other calcs say I'd end up with 5.25, starting with 1.1 gallons less. I think that grain absorption rate is the culprit. Using your calc next time.
 
You're no closer to solving your efficiency question. 2.1 quarts/lb is high already.

Are you taking a reading when it is still hot? Correcting for temperature?
 
Yes sir. I get it down to around 100 usually before I check it and then adjust for temp. Hydrometer is calibrated as well.
 
I just measured everything. The basket is leaving a little over 2 gallons at the bottom. Could that be an issue?
 
I have been using calculators. This was my best efficiency to date. I'm going to crush even finer next time. I have a real bag coming too instead of using paint strainers. I have a feeling they are not letting the mash thin out enough. A lot of water lays below the bag because it only fits the basket in the kettle.

Priceless, I may have plugged in a wrong number somewhere, but your calculator told me I needed 1.1 gallons more than a couple other calculators did. Maybe it was right but it made me nervous.

Throw a screenshot up and I'll take a look. And yes two gallons of loss is significant.
 
here you go

priceless calculator.png
 
here you go

Looks accurate for the details input
batch size is 5.5
Grain loss is 13.5x0.08=1.04
Hop loss is 6x0.0365=.22
Trub loss is .2
Boil off is 1.25

Total needed is those added together 8.24x

Most other calculators do not allow for hop absorption or trub loss, so that's .4G. Most default batch size is 5G, not 5.5G. However usually there is about half a gallon loss between fermentation and packaging so it makes more sense to me for 5.5 to be the default from kettle to primary.

Together that's about a gallon difference, which of course you can adjust by setting hop absorption to 0, trub loss to 0, and batch size to 5.0.
 
Throw a screenshot up and I'll take a look. And yes two gallons of loss is significant.

I don't "lose" the two gallons, they just aren't in contact with the grains during the mash. I didn't think it would be an issue if I stirred enough but I'm starting to think it may be.
 
Oh I gotcha now. You can compensate for that some by stirring more frequently durinf the mash. This'll cause more heat loss though, so just keep it in mind
 
I just measured everything. The basket is leaving a little over 2 gallons at the bottom. Could that be an issue?

I also use a basket in the BK with the bag in the basket. With my 62 qt BK, I have 2.5 gal below the basket. I recently ran a couple of experiments where I got 85 & 89% mash efficiency, and 82 & 84% brewhouse efficiency. These experiments involved sparging rather than a full volume, no-sparge mash, but I doubt a full volume mash would be much lower in efficiency. So, it is possible to get good efficiencies with the configuration you have. Sorry I can't offer any insight into why your efficiency is so low.

I mill my own grain with the roller gap set to 0.016" (Barley Crusher.)

Brew on :mug:
 
Last edited:
I got 81% doing BIAB but I did a sparge over the hanging bag to get boil vol. I used my Bayou Classic MT with 2 gallons under the false bottom. Mashed as usual except with the bag. Used 170 sparge water.

Then after the bag dripped I yanked the FB and boiled.
 
I have a corona mill so I don't think there's a way to measure gap. I get a lot of flour though. A lot to me anyway. I only just started milling my own. I will tighten it up a little more next time.
 
Oh I gotcha now. You can compensate for that some by stirring more frequently durinf the mash. This'll cause more heat loss though, so just keep it in mind

Priceless, out of curiosity, what parameters cause the mash thickness of you calculator to change? For this past brew it called for 2.44 qts per lb. At 13.5 lbs. My next brew will be 10 lbs, calling for 3.19 qts per lb. Same amount of hops.
 
Priceless, out of curiosity, what parameters cause the mash thickness of you calculator to change? For this past brew it called for 2.44 qts per lb. At 13.5 lbs. My next brew will be 10 lbs, calling for 3.19 qts per lb. Same amount of hops.

In short: Mash volume and grain bill.

In Long: Grain bill dictates some of the total water needed, which affects how much mash volume will fit in the pot, which affects how much you might have to sparge.

Grain bill. More grains means more water absorbed.
If you sparge or not, and how much. More you sparge, the thicker the mash.
Grain absorption.
Higher absorption means more water is lost, so mash is thinner.
Batch Size More beer means more water.
Boil off rate
Hop bill, and hop absorption. Since they'll absorp some wort in the boil.
Trub loss between kettle and primary.

Only thing that doesn't affect it in some way is the temps lol.

Strictly the mash thickness is = Strike volume * 4 / Gbill.

The 4 is because mash thickness is in quarts, but volumes are in gallons.
 
Hey everyone. I read more and more that the more water that you mash with the better efficiency will be. Today I mashed with 2.1 qt to lb and ended up with 62 percent. 90 minute mash, lots of stirring. I'm crushing super fine. Gonna start checking ph, but if I bump the water up how do I not end up with too much wort? Just boil longer?

Why the lots of stirring. It's not needed during Sacc rest. More opening of the pot removing your insulation the more heat escapes, the less stable your mash temps become. This can effect your mash efficiency and your ensuing brewhouse efficiency drastically.

Mashing with BIAB is no different than with a more conventional mash tun. Some like to stir some do not. There is no indication based on the chemistry to stir during a mash. The starches convert to sugar in the presence of water and heat and the enzymes in the grain. If you are losing heat and need to stir to reduce stratification during reheating of the mash that is a different story. Opening the pot to stir will cause you to lose heat so the problem is circular. I mash-in stirring constantly and thoroughly, put the lid on, wrap the pot in an insulating jacket and leave it. I monitor temps throughout with a probe and rarely lose even 1 degree F. Once the Sacc rest is complete I mash out, heating to 168 stirring constantly (9 mins usually for my setup). Then it sits for 10 mins covered and insulated. I stir once more and lauter.

I usually start early in the am so am back in bed for my 60-90 min mash. Getting almost 90% mash and 76-78% brewhouse efficiency this way.

I would advise reading the stickied BIAB method in the BIAB section
https://www.homebrewtalk.com/f244/bia...g-pics-233289/

For smaller pots than mine, placing it in an oven at the mash temp is also very effective. Again no stirring is used. Check out "Texas Wine"'s postings on the subject. He is very knowledgeable. Wilserbrew is also very well informed.

Stir if you feel you need to but it is not mandated by the science nor results. A constant recirculating mash with PID temperature control is possible and many do that to up the efficiency. That is beyond my setup and budget for now.
 
I just measured everything. The basket is leaving a little over 2 gallons at the bottom. Could that be an issue?


2 gallons "outside" the mash for a 5 gallon batch is substantial. I don't prefer using baskets for this reason. If I were to do this, I would at least dunk the basket and drain it several times prior to removal. You need to rinse well or sparge with the entire volume IMO.


Wilserbrewer
Http://biabbags.webs.com/
 
I had a feeling. Gavin, I was stirring because of the 2 gallons under the basket that weren't in direct contact with the grains.
 
I had a feeling. Gavin, I was stirring because of the 2 gallons under the basket that weren't in direct contact with the grains.

I'd lose the basket unless its dictated by the weight of your grains. In that case your probably needing a pulley of some sort in which case you can still lose the basket. For 5 gallon batches you looking at 10-12 lbs of grain depending on recipe efficiency and planned OG. That is no problem to lift without a basket or pulley. For 10 gallon batches that would be a struggle and would for sure need a pulley +/- basket. Either way the basket is not mandatory especially if you feel it's not allowing even water/grain distribution. I'm not sure how that space under the basket would affect mash efficiency.

Generally with BIAB the thinking is the higher the water:grain ratio the better mash efficiency. If some of your water is not involved that would likely lower your eff. I'm not sure though. Lots use baskets and don't report problems.
 
I agree with not using a basket, the two gallons at the bottom isn't getting sufficiently mixed with your grain. Also your original post doesn't say what mash temp you started at or if you monitored it during the 90 min mash.
I mash in a cooler and stir every 15 mins and check the temp. Some don't stir at all. My house is older and and drafty and on a cold day I'll loose some mash temperature, but I just have more hot water ready and use an online calculator I found on the green bay rackers website to bring the temp back up, maybe somewhat labor intensive but it works.
 
II used the basket because paint strainer bags fit it perfectly. I got a brew bag now so im looking forward to trying it out without the basket.

I mashed at 153 and it barely dropped the whole time.
 
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