[Richard]

You may increase your extraction percentage slightly by using more water, but then you have to boil longer to get rid of all that water. The cost of your fuel (or electricity) for the boil is not zero, and the negative impacts of a very long boil on your beer need to be considered. There is a sweet spot in there, but where it lies depends on the brewer.

[Lazy Ant Brewing]

Responding to Denny's quote of 75% efficiency I brew BIAB several times a year and only get 71% efficiency. 

With one of my typical recipes, I'll heat 8.75 gallons of water to the strike temp in a 10 gal. pot and add 12.5 lbs of grain to mash.  I stir quite rapidly as I'm adding the double-crushed grain to the pot so my water doesn't cool to much, put the lid on, insulate the pot and mash for 60 minutes.  Then with a hoist, I'll raise the bag directly above the pot and keep it suspended while I squeeze the grain bag with insulated gloves to try to get the last drop of wort to boil. Then I'll set the bag with the wet grain into a bucket and let it drain for a few more minutes as I heating up the wort to begin the boil phase.  Then add the remainder of the wort that drained from the grain bag into the bucket.  NO SPARGE!

The 71% efficiency seems about the best efficiency I can average.  I think my limiting factor might be the very full pot of water and grain  and the difficulty of getting the grain mixed in a short amount of time so as to maintain the strike temp. I use a long-handle metal spoon and stir vigorously. I never heat the pot after the grain is in the bag for fear of burning the bag.  I double crush my grain and it seems pretty fine to me  although I don't have the series of screens required to measure the results nor feeler gauges to check the gap in my mill.

I suppose I could brew a smaller batch size of the same recipe and see if having a bit less volume of grain and water to mix might result in better efficiency.

I'd appreciate any comments about improving my efficiency, and thanks in advance for your advice.

[denny]

Responding to Denny's quote of 75% efficiency I brew BIAB several times a year and only get 71% efficiency. 

With one of my typical recipes, I'll heat 8.75 gallons of water to the strike temp in a 10 gal. pot and add 12.5 lbs of grain to mash.  I stir quite rapidly as I'm adding the double-crushed grain to the pot so my water doesn't cool to much, put the lid on, insulate the pot and mash for 60 minutes.  Then with a hoist, I'll raise the bag directly above the pot and keep it suspended while I squeeze the grain bag with insulated gloves to try to get the last drop of wort to boil. Then I'll set the bag with the wet grain into a bucket and let it drain for a few more minutes as I heating up the wort to begin the boil phase.  Then add the remainder of the wort that drained from the grain bag into the bucket.  NO SPARGE!

The 71% efficiency seems about the best efficiency I can average.  I think my limiting factor might be the very full pot of water and grain  and the difficulty of getting the grain mixed in a short amount of time so as to maintain the strike temp. I use a long-handle metal spoon and stir vigorously. I never heat the pot after the grain is in the bag for fear of burning the bag.  I double crush my grain and it seems pretty fine to me  although I don't have the series of screens required to measure the results nor feeler gauges to check the gap in my mill.

I suppose I could brew a smaller batch size of the same recipe and see if having a bit less volume of grain and water to mix might result in better efficiency.

I'd appreciate any comments about improving my efficiency, and thanks in advance for your advice.

I gently stir/agitate the bag several times during the mash.  I have no idea what the official view on that is.  I also do a small sparge.

[BrewBama]

There are a few numerators and denominators that go into the efficiency equation. If you leave any sweet wort in the MLT, any bitter wort in the BK along with the trüb,  any beer in the FV with the trüb your efficiency is dropping. ....but those known losses along with grain absorption are what we plan for.  Sparging helps pull remaining sugar from the partially spent grain. 71% ain’t bad. I plan for 68% in the FV.  If your beer is where you want it I wouldn’t change a thing.


Sent from my iPad using Tapatalk

[Megary]

Responding to Denny's quote of 75% efficiency I brew BIAB several times a year and only get 71% efficiency. 

With one of my typical recipes, I'll heat 8.75 gallons of water to the strike temp in a 10 gal. pot and add 12.5 lbs of grain to mash.  I stir quite rapidly as I'm adding the double-crushed grain to the pot so my water doesn't cool to much, put the lid on, insulate the pot and mash for 60 minutes.  Then with a hoist, I'll raise the bag directly above the pot and keep it suspended while I squeeze the grain bag with insulated gloves to try to get the last drop of wort to boil. Then I'll set the bag with the wet grain into a bucket and let it drain for a few more minutes as I heating up the wort to begin the boil phase.  Then add the remainder of the wort that drained from the grain bag into the bucket.  NO SPARGE!

The 71% efficiency seems about the best efficiency I can average.  I think my limiting factor might be the very full pot of water and grain  and the difficulty of getting the grain mixed in a short amount of time so as to maintain the strike temp. I use a long-handle metal spoon and stir vigorously. I never heat the pot after the grain is in the bag for fear of burning the bag.  I double crush my grain and it seems pretty fine to me  although I don't have the series of screens required to measure the results nor feeler gauges to check the gap in my mill.

I suppose I could brew a smaller batch size of the same recipe and see if having a bit less volume of grain and water to mix might result in better efficiency.

I'd appreciate any comments about improving my efficiency, and thanks in advance for your advice.

I firmly believe that the right crush is the Holy Grail for BIAB efficiency.  BUT...there has to be other practices that can help.  Like Denny, I stir my mash as well, usually every 10 minutes or so right before I check the mash temp.  I doubt that helps efficiency much, but I tell myself it does.

Funny thing is that the best efficiency I ever got was not with the finest crush I ever used - but it did have the largest water:grain ratio and it was the smallest gravity beer I ever brewed 1.040.  I'm NOT saying that's why I got the efficiency I did, but it is what got me thinking about the possibility.

I continue struggling with the idea that the boil time and grain weight is what sets the strike volume...like the water has no say in the matter.  I think it should be the other way around.  Think about the water:grain ratio as you brew bigger and bigger beers.  I'll guess that your example above is for a 1.050 beer.  .7gal for every pound of grain.  That is exactly what my software tells me I should use for my 1.050 beers (60 minute boil).  But if I want to brew a 1.070 beer, then it becomes .53gal for every #.  That best-efficiency 1.040 beer I brewed had a water:grain ratio .9 gal/lb.  I don't remember how I arrived at that ratio because it isn't what I would use now, but there it is.

I don't want to be boiling for hours or taking all day to brew a batch. But I do want to find the right mash water/boil mix.  I could see mashes getting shorter while boils get a bit longer.  Or maybe I'm chasing my tail.

[Lazy Ant Brewing]

Thanks to all who replied to my specific question.  I am generally pleased with the results of my brewing and like beers in the 1.045 to 1.055 range.  I may try stirring occasionally while mashing and see what happens. Cheers!

[Big Monk]

Responding to Denny's quote of 75% efficiency I brew BIAB several times a year and only get 71% efficiency. 

With one of my typical recipes, I'll heat 8.75 gallons of water to the strike temp in a 10 gal. pot and add 12.5 lbs of grain to mash.  I stir quite rapidly as I'm adding the double-crushed grain to the pot so my water doesn't cool to much, put the lid on, insulate the pot and mash for 60 minutes.  Then with a hoist, I'll raise the bag directly above the pot and keep it suspended while I squeeze the grain bag with insulated gloves to try to get the last drop of wort to boil. Then I'll set the bag with the wet grain into a bucket and let it drain for a few more minutes as I heating up the wort to begin the boil phase.  Then add the remainder of the wort that drained from the grain bag into the bucket.  NO SPARGE!

The 71% efficiency seems about the best efficiency I can average.  I think my limiting factor might be the very full pot of water and grain  and the difficulty of getting the grain mixed in a short amount of time so as to maintain the strike temp. I use a long-handle metal spoon and stir vigorously. I never heat the pot after the grain is in the bag for fear of burning the bag.  I double crush my grain and it seems pretty fine to me  although I don't have the series of screens required to measure the results nor feeler gauges to check the gap in my mill.

I suppose I could brew a smaller batch size of the same recipe and see if having a bit less volume of grain and water to mix might result in better efficiency.

I'd appreciate any comments about improving my efficiency, and thanks in advance for your advice.

I firmly believe that the right crush is the Holy Grail for BIAB efficiency.  BUT...there has to be other practices that can help.  Like Denny, I stir my mash as well, usually every 10 minutes or so right before I check the mash temp.  I doubt that helps efficiency much, but I tell myself it does.

Funny thing is that the best efficiency I ever got was not with the finest crush I ever used - but it did have the largest water:grain ratio and it was the smallest gravity beer I ever brewed 1.040.  I'm NOT saying that's why I got the efficiency I did, but it is what got me thinking about the possibility.

I continue struggling with the idea that the boil time and grain weight is what sets the strike volume...like the water has no say in the matter.  I think it should be the other way around.  Think about the water:grain ratio as you brew bigger and bigger beers.  I'll guess that your example above is for a 1.050 beer.  .7gal for every pound of grain.  That is exactly what my software tells me I should use for my 1.050 beers (60 minute boil).  But if I want to brew a 1.070 beer, then it becomes .53gal for every #.  That best-efficiency 1.040 beer I brewed had a water:grain ratio .9 gal/lb.  I don't remember how I arrived at that ratio because it isn't what I would use now, but there it is.

I don't want to be boiling for hours or taking all day to brew a batch. But I do want to find the right mash water/boil mix.  I could see mashes getting shorter while boils get a bit longer.  Or maybe I'm chasing my tail.

I think you are making this more difficult than it has to be. For instance, I start with my desired packaged volume of beer, and then I account for all the particular losses in my system until, in tandem with the grain weight for that batch, my spreadsheet tells me the required amount of strike water to use.

I have dove deep into this topic and have a good handle on it. What part is troubling you? Maybe I can help.

[Megary]

Undoubtedly I am making this more difficult than it has to be!   

And you have been incredibly helpful so far, so thanks a bunch.

Like you, I have a set into-the-keg batch size.  I have known fermenter losses, kettle losses, boil losses and grain absorption losses.  I feel that that part of my system is pretty well dialed in.  Took me a bit, but I'm good there.  I calculate my Strike Volume by hand and use Brewer's Friend.  Both match up exactly and I usually hit my numbers.

My issue...

With a fixed Batch Size, the strike volume:grain ratio always changes based on 1) the expected ending gravity of the beer (grain weight) and 2) length of boil.  Assuming a normal 60 minute boil, that loss is constant for every batch.  So the strike volume really only changes (slightly) based on some grain absorption value (.1 gal/lb.). As the gravity of beer we want to brew goes up, there is significantly less strike water per pound of grain.  And anecdotally, the higher the gravity of beer we want to brew, the worse our efficiency usually is.  I always read people recommending to adjust your efficiency when brewing big beers..."better add more grain", they say!  To me, that seems like compounding the problem.  Maybe they should thin the mash.

So what *should* the strike volume:grain ratio be for best BIAB mashing?  Is there an ideal ratio? Or do we just go with whatever the calculator spits out because it knows we only want to boil for an hour (or whatever we enter)?

I seem to get better efficiency with thinner mashes, but I've adjusted so many things (crush, Mash pH, brew kettle...) that I can't pin anything down for sure.

Again, I'm not sure there's a correct answer, and even if there is, it won't be the same for everyone.

[Big Monk]

Undoubtedly I am making this more difficult than it has to be!   

And you have been incredibly helpful so far, so thanks a bunch.

Like you, I have a set into-the-keg batch size.  I have known fermenter losses, kettle losses, boil losses and grain absorption losses.  I feel that that part of my system is pretty well dialed in.  Took me a bit, but I'm good there.  I calculate my Strike Volume by hand and use Brewer's Friend.  Both match up exactly and I usually hit my numbers.

My issue...

With a fixed Batch Size, the strike volume:grain ratio always changes based on 1) the expected ending gravity of the beer (grain weight) and 2) length of boil.  Assuming a normal 60 minute boil, that loss is constant for every batch.  So the strike volume really only changes (slightly) based on some grain absorption value (.1 gal/lb.). As the gravity of beer we want to brew goes up, there is significantly less strike water per pound of grain.  And anecdotally, the higher the gravity of beer we want to brew, the worse our efficiency usually is.  I always read people recommending to adjust your efficiency when brewing big beers..."better add more grain", they say!  To me, that seems like compounding the problem.  Maybe they should thin the mash.

So what *should* the strike volume:grain ratio be for best BIAB mashing?  Is there an ideal ratio? Or do we just go with whatever the calculator spits out because it knows we only want to boil for an hour (or whatever we enter)?

I seem to get better efficiency with thinner mashes, but I've adjusted so many things (crush, Mash pH, brew kettle...) that I can't pin anything down for sure.

Again, I'm not sure there's a correct answer, and even if there is, it won't be the same for everyone.

I think part of the issue is using the water to grist ratio as some sort of important input to calculations. In my spreadsheet, water to grist ratio is treated simply as a consequence of how much grain I put in a certain amount of water. It is not a value used in any other calculations.

I think you need to abandon the idea that a thinner mash is helpful with a bigger beer. As we’ve stated previously, the better extraction in a thinner mash is marginal compared to the overwhelming losses to grain absorption inherent in bigger beers with more grain.

The best water to grain ratio is the one that gets you the gravity AND volume you want into your packaging vessels. While I’m not at all concerned about efficiency, I’ve always managed 80%+ Mash efficiency with recirculated no-sparge.

[BrewBama]

Using BeerSmith, water to grist ratio plus system losses dictates the water volumes. Sounds like your spreadsheet is the other way around. IOW, I start with my equipment losses, my desired 1.75:1, then add grain to a recipe, and out pops water volume to be used.  Other software packages may calculate differently.

I thought BIAB was supposed to be easier. There are no losses in pumps, hoses, MLT, etc.. Simply grain absorption to account for so efficiency climbs.

Based on this assumption, if I were to BIAB, I would add 8.5 gal water to a kettle, lower my bag of finely crushed grain, mash for however long, lift the bag and believe I’d get a ~7-7.5 gal full volume to boil after it drains.  If I didn’t get what I wanted, I’d take a note and adjust next brew. Before long, I’d have an absorption rate to use for every brewday thereafter.

The key is consistency. Do it the same way every time so results can be predicted. Don’t squeeze one time and not the other, use a different mill gap brew to brew, or use a different water:grist brewday to brewday, or anything else.

Pardon me if I seem confused. I guess I don’t see the problem.

Sent from my iPad using Tapatalk

[Big Monk]

Using BeerSmith, water to grist ratio plus system losses dictates the water volumes. Sounds like your spreadsheet is the other way around. IOW, I start with my equipment losses, my desired 1.75:1, then add grain to a recipe, and out pops water volume to be used.  Other software packages may calculate differently.

I thought BIAB was supposed to be easier. There are no losses in pumps, hoses, MLT, etc.. Simply grain absorption to account for so efficiency climbs.

Based on this assumption, if I were to BIAB, I would add 8.5 gal water to a kettle, lower my bag of finely crushed grain, mash for however long, lift the bag and believe I’d get a ~7-7.5 gal full volume to boil after it drains.  If I didn’t get what I wanted, I’d take a note and adjust next brew. Before long, I’d have an absorption rate to use for every brewday thereafter.

The key is consistency. Do it the same way every time so results can be predicted. Don’t squeeze one time and not the other, use a different mill gap brew to brew, or use a different water:grist brewday to brewday, or anything else.

Pardon me if I seem confused. I guess I don’t see the problem.

Sent from my iPad using Tapatalk

I’m with you. I’m not sure I understand if there I actually an issue or just a thought experiment at hand.

[Megary]

A thought experiment for sure.

Big Monk, if you were to BIAB brew a 1.040 beer, approximately what would your water:grist ratio be?  How about if you brewed a 1.060 beer?  1.080?
You say this ratio is just a "consequence of how much grain I put in a certain amount of water".  I think it's more than just a consequence.  Of course I have no proof and that's why I started this thread.

I might be wrong and I'm fine with that.  I'm not proud, I've been wrong plenty.   

[Big Monk]

A thought experiment for sure.

Big Monk, if you were to BIAB brew a 1.040 beer, approximately what would your water:grist ratio be?  How about if you brewed a 1.060 beer?  1.080?
You say this ratio is just a "consequence of how much grain I put in a certain amount of water".  I think it's more than just a consequence.  Of course I have no proof and that's why I started this thread.

I might be wrong and I'm fine with that.  I'm not proud, I've been wrong plenty.   

Just so you understand where I’m coming from, I brew no-sparge with constant recirculation using a BIAB bag as a mash filter and a false bottom. I’m concerned with efficiency and extract not because I’m a miser, but because my one shot at hitting my numbers is basically my first wort.

Water to grain ratio has zero impact on my calculations. That’s what I mean about it being merely a consequence of mixing water and grain. If I were to brew a 1.040 beer using my system, my water to grain ratio would depend on how much grain I would need in tandem with my desired packaged volume. And so on and so forth.

To your original point, I think a more dilute mash has better extraction possibilities and I routinely mash at the higher end of the l/kg range. I only know that because as an afterthought I have a cell that calculates water to grain ratio as pure information.

I’ll try to run some numbers in my spreadsheet and give you something to chew on maybe Monday or Tuesday.

The big thing is this: I don’t think water to grain ratio is as important a driver as you feel it might be. Do you have a specific batch recently that’s troubling you numbers wise? I love to troubleshoot.

[Megary]

Actually I'm pretty consistent in the low 70's so this is more about theory.  Sorry if this feels like a waste of time.

One last example.  This is a simplified version of how I calculate my BIAB strike water.  Single infusion, no sparge.  Dunk the bag, drain the bag.  As basic as it gets.

Assume:
10# Grain
.1 gal/lb Grain Absorption
1 gal/hour Boil off
60 minute boil

If I want 5.5 gallons post-boil, then:
5.5 gal + 1 gallon boil off + 1 gallon absorption = 7.5 gallons of Strike Water
.75 gallons/lb. ratio.

If that were 12# grain, doing the math gives a 7.7 gallon Strike, .64 grist ratio.

14#...7.9 strike, .56 ratio.

The ratio falls off pretty quickly.  And this is all in the same kettle.  Not a bigger kettle for a bigger brew.  What really makes this bizarre is that if I wanted to Strike that 14# example to a .75 grist ratio, I would need 10.5 gallons of water and would have to boil for 3-1/2 hours to get down to 5.5 gallons!  Yeah, that ain't happening.  (And I'm not saying .75 is some magic number...just using it as an example.)

My whole point was to try and find some ideal ratio or range of water/grist ratio to stay within.  That would definitely assume that a thinner mash is more efficient and that a range is worth looking for.  Does it even exist?  Does it even matter?

I have no idea.

My compliments to anyone who has bothered to read all of this.

[Big Monk]

Actually I'm pretty consistent in the low 70's so this is more about theory.  Sorry if this feels like a waste of time.

One last example.  This is a simplified version of how I calculate my BIAB strike water.  Single infusion, no sparge.  Dunk the bag, drain the bag.  As basic as it gets.

Assume:
10# Grain
.1 gal/lb Grain Absorption
1 gal/hour Boil off
60 minute boil

If I want 5.5 gallons post-boil, then:
5.5 gal + 1 gallon boil off + 1 gallon absorption = 7.5 gallons of Strike Water
.75 gallons/lb. ratio.

If that were 12# grain, doing the math gives a 7.7 gallon Strike, .64 grist ratio.

14#...7.9 strike, .56 ratio.

The ratio falls off pretty quickly.  And this is all in the same kettle.  Not a bigger kettle for a bigger brew.  What really makes this bizarre is that if I wanted to Strike that 14# example to a .75 grist ratio, I would need 10.5 gallons of water and would have to boil for 3-1/2 hours to get down to 5.5 gallons!  Yeah, that ain't happening.  (And I'm not saying .75 is some magic number...just using it as an example.)

My whole point was to try and find some ideal ratio or range of water/grist ratio to stay within.  That would definitely assume that a thinner mash is more efficient and that a range is worth looking for.  Does it even exist?  Does it even matter?

I have no idea.

My compliments to anyone who has bothered to read all of this.

This post should prove to you the ratio is irrelevant. Your efficiency is steady, yes? Your gravity is good, yes? You get the volume you need, yes?

Thought experiments are good fun. This one is a dead end. Keep doing what you’re doing.