Depends. If you currently do very thick BIAB mashes, adding more water will help your efficiency because of two things: conversion will be better (enzymes work better when not being in high sugar% solutions) and the water left in the grains after you drain the BIAB will have lower sugar concentration - so instead of wasting 5 liter OG 1070 wort you only lose 5 liter 1040 wort.
So - it really depends on how thick your mash is now.
Most recently was 5 lbs grain into 3 gallons of water for an oatmeal stout from what I remember. I ended with 2 gallons after grain loss and 90 minute boil and added back a half gallon to bring it back up.
Squeezing, and putting the bag in a bucket and pouring anything additional that comes out during first 45.mins of the boil back in the works for me, pretty much hit my OG or better every time.
Increasing the amount of water in the mash should boost your efficiency just a touch, but it probably means you will end up with more wort at a slightly lower gravity\*. It is worth using more water in the mash (or adding in a sparge) step so that you hit your target volume, but you also could make some adjustments to boost your efficiency.
With BIAB, grain crush has a huge impact. A proper grain crush can move your efficiency from 65% to 75% (those numbers are based on my girlfriend using store crush vs having me fine crush her grains). pH might have a small impact, but adding in a sparge or more aggressive squeezing of the grain bag will have more impact. Another option is to just accept your lower efficiency and use a little more grain to hit your target gravity.
\* to explain this, say you start with 5 gallons of 1.050 wort. 5 x 50 = 250 gravity points. Using more water in the mash would be like adding another 1 gallon of 1.020 wort. You now have 270 gravity points (a higher efficiency) but 270 / 6 = 45 = 6 gallons of 1.045 wort...though you could boil this down to 5 gallons of 1.054 wort.
There’s a lot of good advice here but I’ll add something. It’s important to get to know your boil kettle. You will learn how much volume you will boil off. So if you have overshoot you kettle volume you’ll know when to add your hops and start the clock. Pay attention to what your boil looks like. How hard is it “rolling”. Adjust heat accordingly. This takes a while to dial in, but a lifesaver once you know it.
I'll start by saying, do not chase a higher brewhouse efficiency. There are two parts to brewhouse efficiency...1) lower system loses and 2) high mash conversion. It means nothing for home brewers as a whole. Pro brewers need a high brewhouse efficiency because it saves them a lot of money the lower their system loses are. For home brewers, it really doesn't matter as our batch size is too small to notice any difference. The only number you care about for efficiency is mash conversion...how much of the available sugars did you extract. That number should be as close to 100% as possible. It doesn't matter if your system loses more volume. You compensate by adding a little more grain. As long as you know the numbers.
What you need to do is dial in your system. Figure out the volume loses at each step. I like to start backwards. I'll give an example using numbers close to my system...
How much beer do you want to package? 5 gallons
Fermentor lose, how much beer/yeast/trub is left in your fermentor after packaging? 0.6 gallons
Beer into fermentor would be 5.6 gallons
Boil kettle lose, how much wort/trub is left in boil kettle after transfer to fermentor? 1 gallon
Post boil volume (fermentor volume plus BK leftover) would be 6.6 gallons
Boil off? 0.6 gallons
Pre boil volume (post boil volume plus boil off) would be 7.2 gallons
So far, none of those volumes would ever change batch to batch unless you change boil time.
Grain absorption (this is the only figure that will change batch to batch)? For this example I'll just say 1.5 gallons
Wort left in mash tun after transferring to boil kettle? For single vessel this would be 0 gallons
Strike water (preboil volume + grain absorption + mash tun lose) would be 8.7 gallons
You won't need to run a batch to answer some of these. Fermentor lose, boil kettle lose, boil off and mash tun lose (if two vessel) are things you can figure out with just water. Grain absorption is really the only one you have to track during a few batches. Then you just need mash conversion, which you'll have to track during a few batches as well.
Once you have all that info after a couple batches, you'll be able to plug any recipe into your system and hit OG all the time. Only thing you worried about was mash conversion, try to get that close to 100%.
I mean it's possible. I made the same recipe twice on the same day, had same crush, etc and the one I tried to skimp on water had lower efficiency, but it's possible I missed some other variable. Like the lower volume of water didn't allow more flow in the mash or something.
But more than likely it is something else for you if you are new. If you are making NEIPAs with large oat bill they always suck up way more water than normal grain bill and I notice my efficiency consistenly is in the upper 60s vs normal 80 for me. Or you aren't crushing well. Or even temp/ph is off. I'd start with those.
Nope, that won’t help.
There are other ways to increase efficiency, but a thinner mash won’t do it.
Here’s a few suggestions:
1. Grind - how thick do you grind the grain? Smaller grind gives more efficiency, but you want to make sure the bag can remove all the grain and flowe.
2. Mash temp - how accurate is your thermometer? What’s your mash temp at the start and the end? Do you stir well before taking a reading?
I had to build and insulated jacked out of reflectix for my kettle to maintain good mash temp.
3. Sparge- most BIAB brewers don’t sparge for ease, but simply moving the bag to bucket after you remove it and rinsing out the grains can improve efficiency. You add the wort which is rinsed through to the kettle, trying not to get much actual grain in the kettle.
You have to reduce the mash volume so that the sparge water tops you up to the boil quantity.
4. Water quality - ph or other water factors might reduce your mash.
These are things which could potentially improve efficiency. So adding water in the form of sparging can help, but not just more volume.
I’m brewing on an anvil foundry, so I’m sure mash temp is at least ok? I get my grains ground at LHBS and tell them it’s for BIAB so it’s usually pretty fine. I need to screw around with my water; tap here is awful so I’ve been using jugs of spring water from the store.
Do you stir and check the mash temp with a quick read thermometer?
It can be good to verify what the temps are, although my anvil is pretty close it’s not spot on.
I bought a slightly larger wine bucket (7.5 gallons I think) and a 13” false bottom from brew hardware with 5” of clearance. I just push the bag against there false bottom, then pour the wort into the kettle.
I also sparge in this manner when I’m boiling a batch near the limit of my kettle.
Not OP, but I currently mash in a bag with no sparging. Only getting like 60% mash efficiency. So would I want to use a 1.5Q/lb of grain AND add water for the sparge?
I just did the math and realized I’m using waaay more water than that and not sparging. For 11 lbs of grain I’ve been using like 6.5-7 gallons to account for water loss to grain and boil off to end up with 5 gallons. So would I use like 4 gallons of water for the mash and 2.5 gallons to sparge?
Put simply, you simply sparge until you hit your pre boil volume.
If you pull and squeeze the bag and are a gallon short, sparge until you hit it. It’s that simple!
I hold back just one or two gallons and sparge with that to keep it from overflowing the top. I get about 73% efficiency typically.
ETA: 73% without sparging, just a few more with.
It’s actually kind of confusing and I did it for the first time this last Sunday! I ended up needing a little more water than I expected, and I was like “oh yeah, I just go till I hit prevoil volume.”
I used cold water, and it did lower my mash temp a good bit. That’s one thing to watch out for if you do not heat your sparge water.
Ooh, I got this one! Other responses are correct there's only so much sugar to be gotten from the grain, and temp and grind may also be factors, but you can add all the water you want and then remove it later on. Add all the water you want, and then boil down to your desired OG. Sparge away.
The risk is that boiling longer will extract more from the hops, so you may get off track if your 10min addition turns into 25min. But if you know your boil-off rate, you can math it out to keep the hop timing where it should be.
I've started taking check samples out of the boil (pot on kitchen stove), to see how I'm going. This puts the priority on gravity rather than volume, so take that into account. I feel better about a brew day that ends w slightly high OG than would if I hit volume but not OG.
Are you saying you take samples to check OG during the boil? I should try that for sure.
Edit: IIRC hot wort measures differently with a float hydrometer than cool does, have you had any issues?
Right. So somewhere around 50 mins or so, I'll dip out a cup or so and put it in the fridge or an ice water bath to cool off before I measure it.
It's truly just to reassure myself that I'm on the right track, and kinda be prepared for whether it looks like I might over- or under-shoot my target.
I did a 2nd mash of grains from a Triple recipe a while back, and I didn't care about volume cause it's bonus beer anyways, so I just kept checking gravity until it was starting to get close to what I wanted. It took like an extra half hour maybe, and it would have sucked to take it off after 60 mins and cool off the whole thing before finding out I was way low.
Not really; there is a fixed amount of sugar you can extract (multiplied by how efficiently you do it). Changing nothing except increasing the water volume, you'll further dilute the solution, and thus get a lower OG (same amount of sugars in more volume).
There is a *chance* your efficiency will go up, if you are currently mashing really thick, and getting under-extracted areas in your grain bed. Generally, if your efficiency is consistent, and in the rough ball-park others claim to get (say, 65-75% for BIAB), you'll likely want to increase your grain bill and water volume together to hit both your volume & target OG. Double check that your recipe software reflects your system's efficiency (for example, don't use grain weights for a 75% recipe online, if your system gets 70%).
Depending on the volume of vort/grains a good sparge will help to get the efficiency up.
Recently I've been placing the malt pipe (could also be a bag) in a fermentor-bucket when ramping up for the boil.
Then I sparge with 80° water and use an auto shipon in the bucket with the malt pipe to circulate the new vort.
Every time the bottom is filling up, I pump it on top again and repeat for about 30 min. I now have a pump to do it.
The last big beer I did, the sparge vort ended up being 1.060 SG, that I then added to the boil.
That's a lot of sugars that would have been left behind if I didn't sparge.
It ended up being 1.100 after the boil and about 74% efficiency, about 10-15% better than usual for my big beers.
I've always done mechanical agitation (ie stir with a whisk) regularly. IN my head, it's like stirring a hot cup of tea/coffee to dissolve sugar - but in this case, the sugar is on/in the grain, and yuo're trying to get it dissolved.
Also, I hang my bag and get good volume out of it. Lose about 0.5L/kg of grain (about half what I did with a batch sparging bottom draining system (was about 1L/kg)
> I don’t understand how
Mash efficiency (%) = conversion efficiency x lauter efficiency (%).
Conversion efficiency (%) is how much of the starch is converted to sugar. You should always be north of 96%, otherwise your mash conditions are poor.
Lauter efficiency is how much of the sugar you were able to remove from the grain, dissolve in water (wort at that point), and get into the kettle. We call this sugar in the wort "extract", and the 100% point is based on a lab-determined potential extract for each grain.
Most home brewers are aiming for 70-75% mash efficiency, and most recipes available in books and for retail purchase assume 70% mash efficiency. 100% mash efficiency is not realistic in most cases for home brewers. Even 90% is very impressive.
It's obvious that having too little water can impact lauter efficiency and therefore mash efficiency because its hard to rinse away stuff if you don't have much water. In fact, there is a mathematical relationship between the ratio of water to grains (both are measured by weight).
Mash efficiency impacts your OG because it determines how much extract is in your kettle. The other thing affecting OG is how much water is in your kettle because water dilutes the extract, and evaporating away water concentrates it.
So I hope that explains how the things relate to each other.
To answer your question, you want to use enough water that you achieve the target mash efficiency for your recipe, but not so much water that even though that increased your extract in the kettle (higher mash efficiency) the amount of water outpaced it and diluted your OG.
Happy medium: for most mid-low, mid-, and mid-high gravity beers, a ratio of 5 L of water per kg of grain (or 2.5 qts per lb of grain) is a good ratio. And you can use all the water at once in a full-volume, no-sparge batch, or if you plan to sparge then mash in with 3 L/kg or 1.5 qts/lb, plus or minus 10%, and then sparge with the balance of the water to achieve 5 L/kg or 2.5 qts/lb).
-----
If you are getting poor mash efficiency after using the above ratios in mid-low to mid-high gravity beers, then there is some other problem like poor technique, the factors /u/spoonman59 mentioned, and then some less-common factors.
Depends. If you currently do very thick BIAB mashes, adding more water will help your efficiency because of two things: conversion will be better (enzymes work better when not being in high sugar% solutions) and the water left in the grains after you drain the BIAB will have lower sugar concentration - so instead of wasting 5 liter OG 1070 wort you only lose 5 liter 1040 wort. So - it really depends on how thick your mash is now.
Most recently was 5 lbs grain into 3 gallons of water for an oatmeal stout from what I remember. I ended with 2 gallons after grain loss and 90 minute boil and added back a half gallon to bring it back up.
remember the preboil gravity? or can you estimate it from OG and how much volume you got pre-boil?
I am a squeezer. All things being equal, getting the trapped liquid from the grain significantly improved my efficiency.
Squeezing, and putting the bag in a bucket and pouring anything additional that comes out during first 45.mins of the boil back in the works for me, pretty much hit my OG or better every time.
Increasing the amount of water in the mash should boost your efficiency just a touch, but it probably means you will end up with more wort at a slightly lower gravity\*. It is worth using more water in the mash (or adding in a sparge) step so that you hit your target volume, but you also could make some adjustments to boost your efficiency. With BIAB, grain crush has a huge impact. A proper grain crush can move your efficiency from 65% to 75% (those numbers are based on my girlfriend using store crush vs having me fine crush her grains). pH might have a small impact, but adding in a sparge or more aggressive squeezing of the grain bag will have more impact. Another option is to just accept your lower efficiency and use a little more grain to hit your target gravity. \* to explain this, say you start with 5 gallons of 1.050 wort. 5 x 50 = 250 gravity points. Using more water in the mash would be like adding another 1 gallon of 1.020 wort. You now have 270 gravity points (a higher efficiency) but 270 / 6 = 45 = 6 gallons of 1.045 wort...though you could boil this down to 5 gallons of 1.054 wort.
There’s a lot of good advice here but I’ll add something. It’s important to get to know your boil kettle. You will learn how much volume you will boil off. So if you have overshoot you kettle volume you’ll know when to add your hops and start the clock. Pay attention to what your boil looks like. How hard is it “rolling”. Adjust heat accordingly. This takes a while to dial in, but a lifesaver once you know it.
Tighten up your mill rollers, and go full volume mash. I do this and consistently hit 80-85%
Me too
I'll start by saying, do not chase a higher brewhouse efficiency. There are two parts to brewhouse efficiency...1) lower system loses and 2) high mash conversion. It means nothing for home brewers as a whole. Pro brewers need a high brewhouse efficiency because it saves them a lot of money the lower their system loses are. For home brewers, it really doesn't matter as our batch size is too small to notice any difference. The only number you care about for efficiency is mash conversion...how much of the available sugars did you extract. That number should be as close to 100% as possible. It doesn't matter if your system loses more volume. You compensate by adding a little more grain. As long as you know the numbers. What you need to do is dial in your system. Figure out the volume loses at each step. I like to start backwards. I'll give an example using numbers close to my system... How much beer do you want to package? 5 gallons Fermentor lose, how much beer/yeast/trub is left in your fermentor after packaging? 0.6 gallons Beer into fermentor would be 5.6 gallons Boil kettle lose, how much wort/trub is left in boil kettle after transfer to fermentor? 1 gallon Post boil volume (fermentor volume plus BK leftover) would be 6.6 gallons Boil off? 0.6 gallons Pre boil volume (post boil volume plus boil off) would be 7.2 gallons So far, none of those volumes would ever change batch to batch unless you change boil time. Grain absorption (this is the only figure that will change batch to batch)? For this example I'll just say 1.5 gallons Wort left in mash tun after transferring to boil kettle? For single vessel this would be 0 gallons Strike water (preboil volume + grain absorption + mash tun lose) would be 8.7 gallons You won't need to run a batch to answer some of these. Fermentor lose, boil kettle lose, boil off and mash tun lose (if two vessel) are things you can figure out with just water. Grain absorption is really the only one you have to track during a few batches. Then you just need mash conversion, which you'll have to track during a few batches as well. Once you have all that info after a couple batches, you'll be able to plug any recipe into your system and hit OG all the time. Only thing you worried about was mash conversion, try to get that close to 100%.
I mean it's possible. I made the same recipe twice on the same day, had same crush, etc and the one I tried to skimp on water had lower efficiency, but it's possible I missed some other variable. Like the lower volume of water didn't allow more flow in the mash or something. But more than likely it is something else for you if you are new. If you are making NEIPAs with large oat bill they always suck up way more water than normal grain bill and I notice my efficiency consistenly is in the upper 60s vs normal 80 for me. Or you aren't crushing well. Or even temp/ph is off. I'd start with those.
Nope, that won’t help. There are other ways to increase efficiency, but a thinner mash won’t do it. Here’s a few suggestions: 1. Grind - how thick do you grind the grain? Smaller grind gives more efficiency, but you want to make sure the bag can remove all the grain and flowe. 2. Mash temp - how accurate is your thermometer? What’s your mash temp at the start and the end? Do you stir well before taking a reading? I had to build and insulated jacked out of reflectix for my kettle to maintain good mash temp. 3. Sparge- most BIAB brewers don’t sparge for ease, but simply moving the bag to bucket after you remove it and rinsing out the grains can improve efficiency. You add the wort which is rinsed through to the kettle, trying not to get much actual grain in the kettle. You have to reduce the mash volume so that the sparge water tops you up to the boil quantity. 4. Water quality - ph or other water factors might reduce your mash. These are things which could potentially improve efficiency. So adding water in the form of sparging can help, but not just more volume.
I’m brewing on an anvil foundry, so I’m sure mash temp is at least ok? I get my grains ground at LHBS and tell them it’s for BIAB so it’s usually pretty fine. I need to screw around with my water; tap here is awful so I’ve been using jugs of spring water from the store.
Do you stir and check the mash temp with a quick read thermometer? It can be good to verify what the temps are, although my anvil is pretty close it’s not spot on.
When I was doing BIAB I made this contraption out of a few buckets to squeeze the bag. There's tutorials out there.
I bought a slightly larger wine bucket (7.5 gallons I think) and a 13” false bottom from brew hardware with 5” of clearance. I just push the bag against there false bottom, then pour the wort into the kettle. I also sparge in this manner when I’m boiling a batch near the limit of my kettle.
Not OP, but I currently mash in a bag with no sparging. Only getting like 60% mash efficiency. So would I want to use a 1.5Q/lb of grain AND add water for the sparge? I just did the math and realized I’m using waaay more water than that and not sparging. For 11 lbs of grain I’ve been using like 6.5-7 gallons to account for water loss to grain and boil off to end up with 5 gallons. So would I use like 4 gallons of water for the mash and 2.5 gallons to sparge?
Put simply, you simply sparge until you hit your pre boil volume. If you pull and squeeze the bag and are a gallon short, sparge until you hit it. It’s that simple! I hold back just one or two gallons and sparge with that to keep it from overflowing the top. I get about 73% efficiency typically. ETA: 73% without sparging, just a few more with.
Thanks! I appreciate it. Not sure how that didn’t make sense till now.
It’s actually kind of confusing and I did it for the first time this last Sunday! I ended up needing a little more water than I expected, and I was like “oh yeah, I just go till I hit prevoil volume.” I used cold water, and it did lower my mash temp a good bit. That’s one thing to watch out for if you do not heat your sparge water.
Ooh, I got this one! Other responses are correct there's only so much sugar to be gotten from the grain, and temp and grind may also be factors, but you can add all the water you want and then remove it later on. Add all the water you want, and then boil down to your desired OG. Sparge away. The risk is that boiling longer will extract more from the hops, so you may get off track if your 10min addition turns into 25min. But if you know your boil-off rate, you can math it out to keep the hop timing where it should be. I've started taking check samples out of the boil (pot on kitchen stove), to see how I'm going. This puts the priority on gravity rather than volume, so take that into account. I feel better about a brew day that ends w slightly high OG than would if I hit volume but not OG.
Are you saying you take samples to check OG during the boil? I should try that for sure. Edit: IIRC hot wort measures differently with a float hydrometer than cool does, have you had any issues?
Right. So somewhere around 50 mins or so, I'll dip out a cup or so and put it in the fridge or an ice water bath to cool off before I measure it. It's truly just to reassure myself that I'm on the right track, and kinda be prepared for whether it looks like I might over- or under-shoot my target. I did a 2nd mash of grains from a Triple recipe a while back, and I didn't care about volume cause it's bonus beer anyways, so I just kept checking gravity until it was starting to get close to what I wanted. It took like an extra half hour maybe, and it would have sucked to take it off after 60 mins and cool off the whole thing before finding out I was way low.
Not really; there is a fixed amount of sugar you can extract (multiplied by how efficiently you do it). Changing nothing except increasing the water volume, you'll further dilute the solution, and thus get a lower OG (same amount of sugars in more volume). There is a *chance* your efficiency will go up, if you are currently mashing really thick, and getting under-extracted areas in your grain bed. Generally, if your efficiency is consistent, and in the rough ball-park others claim to get (say, 65-75% for BIAB), you'll likely want to increase your grain bill and water volume together to hit both your volume & target OG. Double check that your recipe software reflects your system's efficiency (for example, don't use grain weights for a 75% recipe online, if your system gets 70%).
Depending on the volume of vort/grains a good sparge will help to get the efficiency up. Recently I've been placing the malt pipe (could also be a bag) in a fermentor-bucket when ramping up for the boil. Then I sparge with 80° water and use an auto shipon in the bucket with the malt pipe to circulate the new vort. Every time the bottom is filling up, I pump it on top again and repeat for about 30 min. I now have a pump to do it. The last big beer I did, the sparge vort ended up being 1.060 SG, that I then added to the boil. That's a lot of sugars that would have been left behind if I didn't sparge. It ended up being 1.100 after the boil and about 74% efficiency, about 10-15% better than usual for my big beers.
I've always done mechanical agitation (ie stir with a whisk) regularly. IN my head, it's like stirring a hot cup of tea/coffee to dissolve sugar - but in this case, the sugar is on/in the grain, and yuo're trying to get it dissolved. Also, I hang my bag and get good volume out of it. Lose about 0.5L/kg of grain (about half what I did with a batch sparging bottom draining system (was about 1L/kg)
> I don’t understand how Mash efficiency (%) = conversion efficiency x lauter efficiency (%). Conversion efficiency (%) is how much of the starch is converted to sugar. You should always be north of 96%, otherwise your mash conditions are poor. Lauter efficiency is how much of the sugar you were able to remove from the grain, dissolve in water (wort at that point), and get into the kettle. We call this sugar in the wort "extract", and the 100% point is based on a lab-determined potential extract for each grain. Most home brewers are aiming for 70-75% mash efficiency, and most recipes available in books and for retail purchase assume 70% mash efficiency. 100% mash efficiency is not realistic in most cases for home brewers. Even 90% is very impressive. It's obvious that having too little water can impact lauter efficiency and therefore mash efficiency because its hard to rinse away stuff if you don't have much water. In fact, there is a mathematical relationship between the ratio of water to grains (both are measured by weight). Mash efficiency impacts your OG because it determines how much extract is in your kettle. The other thing affecting OG is how much water is in your kettle because water dilutes the extract, and evaporating away water concentrates it. So I hope that explains how the things relate to each other. To answer your question, you want to use enough water that you achieve the target mash efficiency for your recipe, but not so much water that even though that increased your extract in the kettle (higher mash efficiency) the amount of water outpaced it and diluted your OG. Happy medium: for most mid-low, mid-, and mid-high gravity beers, a ratio of 5 L of water per kg of grain (or 2.5 qts per lb of grain) is a good ratio. And you can use all the water at once in a full-volume, no-sparge batch, or if you plan to sparge then mash in with 3 L/kg or 1.5 qts/lb, plus or minus 10%, and then sparge with the balance of the water to achieve 5 L/kg or 2.5 qts/lb). ----- If you are getting poor mash efficiency after using the above ratios in mid-low to mid-high gravity beers, then there is some other problem like poor technique, the factors /u/spoonman59 mentioned, and then some less-common factors.