40% efficiency…

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Pale Ales and Such

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Hi everyone,

just did my first all grain brew (BIAB) method and my gravity was way off what I was expecting (about .30 points off towards the end of the boil) I added about 0.3 ounces of DME and that got me to where I was expecting.

It’s obvious that the grains I bought are not crushed finely enough to be super efficient but I think my other factor was water volume.

I used about 2.5 gallons of water for a 2.25 lb grain bill (trying a one gallon batch for this first all grain attempt).

i bought enough grain so that I have an additional 2.25lbs. With the grain being the same as what I currently tried, should I lower my water volume to maybe 1.5 gallons? I’m going to invest in a mill but until then, wanted to see what I can do with the remaining crushed grain so that I can more sugar out of them.
 
Just did the OG reading and it’s sitting at 1.050, which is about .12 points lower than I wanted but im ok with that.

looking over my notes, my best guess is I overestimated the volume for the water and I should have used 2 gallons over 2.5 gallons. Will try again in the future with that amount and see how it goes.
 
Just did the OG reading and it’s sitting at 1.050, which is about .12 points lower than I wanted but im ok with that.

looking over my notes, my best guess is I overestimated the volume for the water and I should have used 2 gallons over 2.5 gallons. Will try again in the future with that amount and see how it goes.

It sounds like you are confusing gravity with mash efficiency. The latter is a measure of the percentage of theoretically available sugars and dextrins that make it to your boil kettle. In order to compute it, you need to know the potential of your grain bill, the OG, and the volume of wort in your kettle. If you don't consider the actual volume, you can't know the efficiency.

What was your gravity reading and what was the volume of wort in the kettle when you took that reading? Also, what was the temperature of the wort and how did you measure it?
 
It sounds like you are confusing gravity with mash efficiency. The latter is a measure of the percentage of theoretically available sugars and dextrins that make it to your boil kettle. In order to compute it, you need to know the potential of your grain bill, the OG, and the volume of wort in your kettle. If you don't consider the actual volume, you can't know the efficiency.

What was your gravity reading and what was the volume of wort in the kettle when you took that reading? Also, what was the temperature of the wort and how did you measure it?

according to brewers friend, the 100% efficiency of the grains would have the gravity at 1.083. The reading I took was towards the end of the wort boil and I brought it down to 65 degrees before taking the gravity reading which was sitting at 1.035. The volume of the wort, I had to eyeball it, but it looked like 1.5 gallons. I tried to find a good calculator online to see how much DME to add to up the gravity and at this point my “brew day” drunk brain kicked in and I thought it said to add 0.3 ounces when it wanted me to actually add 2.3 ounces (I used this website Gravity Adjustment Calculator | Beginner Brewer).

I then just let it boil about 10 more minutes before shutting off the flame and letting it sit until it reached 180 degrees when I added my hops for a 30 minute hopstand. Then I chilled the wort down to 65 degrees before taking the OG which was sitting at 1.050. After, I poured 1 gallon of thr wort into my carboy (and had about half a cup of wort left in the kettle)

another note: I did take a temp reading of the mash after the 60 minute mash time: it was about 135 degrees.

all of this tells me:
1. My grain is too coarse
2. My mash temp dropped too low
3. I need to have a longer wort boil…maybe?
 
eta: posted at exact same time as #6.

... first all grain brew (BIAB) method

... (trying a one gallon batch for this first all grain attempt)

... should I lower my water volume to maybe 1.5 gallons?

What are you doing for water adjustments to setup good mash conditions?

For my "12-pack" batches, I typically mash in 1.5 gal water, then sparge to get to my initial boil volume. For a true 1 gal (128 oz) batch, I would start with 1.25 gal water, then sparge to get to initial boil volume. I get around 80% efficiency with this approach.
 
What was the batch size (intended wort volume) in your Brewers Friend calculation? Knowing that (or knowing the actual grain bill), we can figure out if you even have a mash efficiency issue or if you're just ending up with too much wort (i.e. using too much total water). Or potentially both.
 
Last edited:
Hi everyone,

just did my first all grain brew (BIAB) method and my gravity was way off what I was expecting (about .30 points off towards the end of the boil) I added about 0.3 ounces of DME and that got me to where I was expecting.

It’s obvious that the grains I bought are not crushed finely enough to be super efficient but I think my other factor was water volume.

I used about 2.5 gallons of water for a 2.25 lb grain bill (trying a one gallon batch for this first all grain attempt).
Yeah your gravity is low, what exactly was the grain bill?
Also, adding some extract to save the beer was a good move, you can also toss in a small amount of sugar/honey to bump the ABV a little more to get where you wanted to be.
Using about 2.5 gallons of water for a 1 gallon batch is what I would use. I figure 1 gallon of finished beer, 1 gallon for evaporation during the boil, 1/2 gallon for water absorbed by the grain and kettle trub/fermenter yeast slurry loss. I might even go 2.75 gallons if I was using a lot of hops in the kettle.
So the question is how are you using that water?
I usually brew 2.5 to 3 gallon batches, but if I was brewing a 1 gallon batch here's what I would do:
Mash using 1.5 gallons of water, when its done, stir the mash a few times, then pull the bag and "dunk sparge" in a another pot or bucket with the remaining 1 gallon of water. The sparge should also be stirred. You can get the boil started while you're doing the dunk sparge. Put a colander over the sparge pot and let the bag drain a while then combine everything.
I run my grain through my mill twice when I BIAB.
See if your supplier will run the grain through the mill twice for you.
The other option is to just use a little more grain and not worry about your efficiency,
 
I think it would be a good idea to figure out if this is a mash efficiency problem or a total water volume problem before solving it.
 
another note: I did take a temp reading of the mash after the 60 minute mash time: it was about 135 degrees.

My suggestion to mash longer assumes that the mash temp stays in the range where conversion occurs. Obviously this would not have helped when the temperature falls so low and if the temperature was 135 after 60 minutes, at what point did it fall below 150. That is the real mash period you had. You need to insulate the mash to keep the temperature within conversion range.
 
My suggestion to mash longer assumes that the mash temp stays in the range where conversion occurs. Obviously this would not have helped when the temperature falls so low and if the temperature was 135 after 60 minutes, at what point did it fall below 150. That is the real mash period you had. You need to insulate the mash to keep the temperature within conversion range.
Yeah, this is a good point. Will insulate it with a towel or something next time. Was thinking of doing temp readings throughout to ensure I maintain the mash temp for exactly one hour.
 
The volume of the wort, I had to eyeball it, but it looked like 1.5 gallons.
If you have a ruler, you can use it to measure the amount of wort that this is in the kettle. Measure the space from the top of the kettle to the top of the wort. Take initial measurements for 1.0 and 1.5 gallons, then calculate the other values.

eta: volumes at 150F will be about 2% larger, volumes at boiling will be about 4% larger.
 
Yeah your gravity is low, what exactly was the grain bill?
Also, adding some extract to save the beer was a good move, you can also toss in a small amount of sugar/honey to bump the ABV a little more to get where you wanted to be.
Using about 2.5 gallons of water for a 1 gallon batch is what I would use. I figure 1 gallon of finished beer, 1 gallon for evaporation during the boil, 1/2 gallon for water absorbed by the grain and kettle trub/fermenter yeast slurry loss. I might even go 2.75 gallons if I was using a lot of hops in the kettle.
So the question is how are you using that water?
I usually brew 2.5 to 3 gallon batches, but if I was brewing a 1 gallon batch here's what I would do:
Mash using 1.5 gallons of water, when its done, stir the mash a few times, then pull the bag and "dunk sparge" in a another pot or bucket with the remaining 1 gallon of water. The sparge should also be stirred. You can get the boil started while you're doing the dunk sparge. Put a colander over the sparge pot and let the bag drain a while then combine everything.
I run my grain through my mill twice when I BIAB.
See if your supplier will run the grain through the mill twice for you.
The other option is to just use a little more grain and not worry about your efficiency,
The wisdom of this is amazing. Thanks
 
If you have a ruler, you can use it to measure the amount of wort that this is in the kettle. Measure the space from the top of the kettle to the top of the wort. Take initial measurements for 1.0 and 1.5 gallons, then calculate the other values.

eta: volumes at 150F will be about 2% larger, volumes at boiling will be about 4% larger.

its the little things like this that I overlook. I will for sure do this with some water to get a more accurate reading
 
eta: posted at exact same time as #6.



What are you doing for water adjustments to setup good mash conditions?

For my "12-pack" batches, I typically mash in 1.5 gal water, then sparge to get to my initial boil volume. For a true 1 gal (128 oz) batch, I would start with 1.25 gal water, then sparge to get to initial boil volume. I get around 80% efficiency with this approach.
Thanks to the wisdom in this thread, im
Learning to make adjustments now.
 
stable mash temperatures: people talk about pre-heating an oven to around 160F, turn the heat off, then putting the mash kettle in the oven.

boil off rate: for the kettle that I use for my very small batches, I boil off about a quart of water in 45 minutes. For boil intensity, I typically use a "simmer / level 1" setting.

 
To everyone replying:
This is truly why I love posting my questions on this site. The wisdom everyone shares is always welcome and I continue to learn so much. I appreciate everyone’s responses and look forward to giving this another shot in the near future. I have but the one 1-gallon carboy so I’m going to let this current batch finish fermenting before I try another biab batch. I won’t be moving to a larger batch size until I’ve mastered a 1-gallon batch
 
In the meantime...
If Brewer's Friend predicted 1.083 for One Gallon of wort with 2.5 lbs of grain at 100% Mash Efficiency, that would mean the average potential of the grain bill was 33.2 Points per Pound Per Gallon. That's pretty low, but we can roll with it for now and correct it as we get more info from the OP. So, we were expecting 83 points in one gallon.

The actual OG was 1.035. And the actual volume of the batch was (maybe) 1.5 gallons. If so...
35 x 1.5 = 52.5 total points

52.5 actual points / 83 theoretical points = 63.3% mash efficiency. 63.3% mash efficiency is not stellar, but it's also not disatrous, and would not be the main driver of OP's low than expected gravity. (I'm assuming OP was not expecting 100% mash efficiency, which is impossible.)

@Pale Ales and Such can you please provide your actual grain bill and/or the intended wort volume from Brewer's Friend? You're getting lots of good general advice, but wouldn't it be nice to know what the actual issue is?
 
Wait.

What was the start of boil volume? End of boil volume? Total grain weight? Total water used?

With those values, not guesstimates, you can figure grain absorbtion and boil off rate and CALCULATE what you need.

Try out Priceless for BIAB, but if you have the values for your system's absorption and boil off you can plug in the numbers to BrewersFriend calc. Everyone's system/process is different. Absorption numbers depend on how you BIAB (no sparge, sparge, gravity drain, squeeze). Boil off is system dependent also, and can vary a little with weather (winter dry, summer humid) but more so how you set the propane dial, stove top electric, etc.
 
In the meantime...
If Brewer's Friend predicted 1.083 for One Gallon of wort with 2.5 lbs of grain at 100% Mash Efficiency, that would mean the average potential of the grain bill was 33.2 Points per Pound Per Gallon. That's pretty low, but we can roll with it for now and correct it as we get more info from the OP. So, we were expecting 83 points in one gallon.

The actual OG was 1.035. And the actual volume of the batch was (maybe) 1.5 gallons. If so...
35 x 1.5 = 52.5 total points

52.5 actual points / 83 theoretical points = 63.3% mash efficiency. 63.3% mash efficiency is not stellar, but it's also not disatrous, and would not be the main driver of OP's low than expected gravity. (I'm assuming OP was not expecting 100% mash efficiency, which is impossible.)

@Pale Ales and Such can you please provide your actual grain bill and/or the intended wort volume from Brewer's Friend? You're getting lots of good general advice, but wouldn't it be nice to know what the actual issue is?

this is the grain bill:
2 lbs: 2-row pale ale
2 oz: Simpsons caramalt
1 oz: Simpsons dark crystal malt
1 oz: Simpsons light crystal malt
 
this is the grain bill:
2 lbs: 2-row pale ale
2 oz: Simpsons caramalt
1 oz: Simpsons dark crystal malt
1 oz: Simpsons light crystal malt

2 lbs 2-row x 37 PPG = 74 points
0.125 lbs caramalt x 34 PPG = 4.25 points
0.0625 lbs dark crystal x 34 PPG = 2.125 points
0.0625 lbs light crystal = 34 PPG = 2.125 points

Total Grain Bill Potential Points = 82.5 (YMMV slightly depending on PPGs assumed by a particular calculator)

The actual OG was 1.035. And the actual volume of the batch was (maybe) 1.5 gallons. If so...
35 x 1.5 = 52.5 total points

52.5 actual points / 82.5 theorectical points = 63.6% Mash Efficiency. Not the major issue.

Personally, I would concentrate first on getting the finished volume correct (given grain absorption and boiloff rate).
 
Was thinking of doing temp readings throughout to ensure I maintain the mash temp for exactly one hour.
If you need to "unwrap" the kettle to take the mash temperature, you may find that you lose 1F for each measurement.

If most of the mash is completed in the first 30 minutes and if mash temperature ± 2F is 'close enough', then the following approach may be reasonable for your next attempt. With a target mash temperature of 152F, calculate strike water temperature for a mash temperature of 154F. Wrap the kettle well, put the lid on, "insulate" the lid as well. Measure the mash temperature at 30 minutes.
 
Or, use the oven. Turn oven on to "warm" or 170. When it reaches that temp, turn it off. Mash in, stir, take temp, lid on, put in the turned off but warm oven. walk away for 60m.

Especially for these 1-2gal batches, the mash/boil/biab pot should be small enough to fit in the oven
 
Or, use the oven. Turn oven on to "warm" or 170. When it reaches that temp, turn it off. Mash in, stir, take temp, lid on, put in the turned off but warm oven. walk away for 60m.

Especially for these 1-2gal batches, the mash/boil/biab pot should be small enough to fit in the oven

I mean, that’s not a bad idea…but I’m not trying to do methods like this when I’m trying to get the technique down to eventually move to a 5 gallon brew
 
Fair enough.
I started with extract/steeping grains and would steep in the 5g boil kettle on stove. That became mashing when I would have some base malts with other malts as well as traditional steeping grains (crystal malts, roasted malts). Then I went to 5 gallon batches, full mash volume, ful boil, BIAB but I had to get a 10g pot, immersion chiller, and move to garage over propane.
But in the beginning, stove top/oven was a great way to hold mash temp with low volumes as they have little heat mass compared to 8.5g.
And if you do the Corona mill, per @RM-MN , and grind fine with a nice BIAB bag (Wilser's are awesome and finer than simple paint strainer bags, ask me how I know) then keeping temp is really only important during conversion, which can be finished in under 15-20m. But mashing an hour I have found important for flavor. Mashing 20m for my altbier for instance made the flavor thin.
Just more data points for ya.
 
With the grain bill revealed, the easy answer is to toss in another 1/4 to 1/2 lb of 2 row and you'll be good.
If you want to use the 2.25lbs of grain you already have, just figure how much extract is 1/4 to 1/2 lb and use that.
Keep your water amounts the same and see what happens.
My 2 cents: Don't over think it, when you have a choice, take the easy route, relax, don't worry have a homebrew.
 
Fair enough.
I started with extract/steeping grains and would steep in the 5g boil kettle on stove. That became mashing when I would have some base malts with other malts as well as traditional steeping grains (crystal malts, roasted malts). Then I went to 5 gallon batches, full mash volume, ful boil, BIAB but I had to get a 10g pot, immersion chiller, and move to garage over propane.
But in the beginning, stove top/oven was a great way to hold mash temp with low volumes as they have little heat mass compared to 8.5g.
And if you do the Corona mill, per @RM-MN , and grind fine with a nice BIAB bag (Wilser's are awesome and finer than simple paint strainer bags, ask me how I know) then keeping temp is really only important during conversion, which can be finished in under 15-20m. But mashing an hour I have found important for flavor. Mashing 20m for my altbier for instance made the flavor thin.
Just more data points for ya.

lol, no joke but we are on the same wavelength. Was just telling my wife about getting a 10 gallon kettle and moving out to my garage for brew days whenever I’m ready to brew 5 gallons lol. I’m probably gonna do this oven method though to save myself from wrapping up the kettle lmfao!! Thanks for all your help here
 
With the grain bill revealed, the easy answer is to toss in another 1/4 to 1/2 lb of 2 row and you'll be good.
If you want to use the 2.25lbs of grain you already have, just figure how much extract is 1/4 to 1/2 lb and use that.
Keep your water amounts the same and see what happens.
My 2 cents: Don't over think it, when you have a choice, take the easy route, relax, don't worry have a homebrew.

love this! Yeah, brewing overall is therapeutic for me so I usually keep calm, even in the face of problems.Heck, my calm brain made me realize that I needed to add DME to up the gravity so I can retain some ABV rather than create a session IPA :).
 
... when I’m trying to get the technique down to eventually move to a 5 gallon brew
If your end goal is five gallon batches, don't initially brew too many more 1 gal batches. While general concepts scale up / down, the techniques are often batch size (and brewer specific).

Once you have a 1) reasonable understanding of how "brewing software" works with one gallon batches, and 2) reasonable understanding of water volumes through-out the brew day, you're probably ready to move to five gallon brewing.

A refractometer makes it much easier to take SG measurements. With my 1.5-ish gal batches, I don't see the wort stratification that others talk about (with 5 gal batches), so I can take post-mash and/or pre-boil SG measurements to confirm that the brew day is on track.

Initially, you can skip the pH meter. If you are using either software to estimate mash pH or a simplified approach to water adjustments (link), measuring mash pH will almost always confirm the software / process is accurate.
 
Using more water in the mash usually ups the efficiency and doesn't lower it.

Yes that's true if you're going boil off that extra volume to concentrate. If your boil off is 1 gallon per hour and you increase your water by 1.5 gallons, you either have to boil off an extra 1/2 gallon (no loss of efficiency) or leave a 1/2 gallon of wort in the kettle as waste (a direct hit to brewhouse efficiency).
 
Ok, just did a test for boil off rate. I put two gallons of water in my 5 gallon kettle and let it boil for an hour. When the hour was up, I had 1 gallon and 6.5 cups left of water. That’s a boil off rate of 0.60 gallons (9.5 cups) for one hour.

looking into the amount of water I need, it seems about 2 gallons.

I plan on doing the mash at 155 degrees with a 2.25lb grain bill in 2 gallons of water then boil for an hour.

thoughts?
 
Well, you can always top of at the end with boiled water so I wouldn't sweat it too much... Just use enough water for your mash to be easy going and efficient.
 
Ok, just did a test for boil off rate. I put two gallons of water in my 5 gallon kettle and let it boil for an hour. When the hour was up, I had 1 gallon and 6.5 cups left of water. That’s a boil off rate of 0.60 gallons (9.5 cups) for one hour.

looking into the amount of water I need, it seems about 2 gallons.

I plan on doing the mash at 155 degrees with a 2.25lb grain bill in 2 gallons of water then boil for an hour.

thoughts?
Determining your boil-off rate as you did is a necessary step, but it appears you may still not have a complete understanding of how to determine how much brewing water you need to start with. These two posts might be of some help to you: 1 2

Brew on :mug:
 
Just an update everyone:

I just did another batch of the exact same recipe, only I used 2 gallons of water for the mash and boil. The volume left after the boil and cool off, was 1.10 gallon. I used the oven method to keep the mash at about 155 degrees

overall, end result of the second batch had an OG of 1.050, which isn’t too bad considering what I got on my first batch.

based on brewers friend, an OG reading of 1.050 would give me 60% efficiency on the grains. This is telling me that my grains were too corse and I probably needed to mash them for another 30 minutes or so.

either way, I just wanted to tell everyone how much fun I’m having with all grain brewing and I look forward to my beer making journey from here as I grow and learn more everyday. A lot of thanks to all of you for your wisdom and help.
 
Did you use the actual volume in your mash efficiency answer this time around? (It doesn't sound like it.)

Total Grain Bill Potential Points = 82.5 (YMMV slightly depending on PPGs assumed by a particular calculator)

The actual OG was 1.050. And the actual volume of the batch was 1.1 gallons.
50 x 1.1= 55 total points

55 actual points / 82.5 theorectical points = 66.7% Mash Efficiency.

You say that Brewers Friend reported 60% mash efficiency. I would guess that you didn't tell it that you got 1.1 gallons. If you entered 1 gallon (because "it's a one gallon batch"), the math would be...

50 x 1 (wrong volume) = 50 (understated) actual points
50 (understated) actual points / 82.5 theoretical points = 60.6% (incorrect) mash efficiency

I can't stress enough that the OG, without the actual volume of wort in the kettle, cannot be used alone to compute mash efficiency.
 
Did you use the actual volume in your mash efficiency answer this time around? (It doesn't sound like it.)

Total Grain Bill Potential Points = 82.5 (YMMV slightly depending on PPGs assumed by a particular calculator)

The actual OG was 1.050. And the actual volume of the batch was 1.1 gallons.
50 x 1.1= 55 total points

55 actual points / 82.5 theorectical points = 66.7% Mash Efficiency.

You say that Brewers Friend reported 60% mash efficiency. I would guess that you didn't tell it that you got 1.1 gallons. If you entered 1 gallon (because "it's a one gallon batch"), the math would be...

50 x 1 (wrong volume) = 50 (understated) actual points
50 (understated) actual points / 82.5 theoretical points = 60.6% (incorrect) mash efficiency

I can't stress enough that the OG, without the actual volume of wort in the kettle, cannot be used alone to compute mash efficiency.

yeah, and that’s my bad for not mentioning it. I did do the math and I to was getting 66.7%, which was confusing so I just lowered the efficiency in brewers friend until the possible OG showed exactly was my reading was. It showed accurate at 60% efficiency.

rethinking my kettle volume remaining before I poured into the fermenter, I’m thinking it was actually less than 1.1 gallons now. When I poured into the fermenter all I really had left in the kettle was troub.

so I’m going to say that perhaps I was off with reading my final volume pre-fermentation pour.
 
yeah, and that’s my bad for not mentioning it. I did do the math and I to was getting 66.7%, which was confusing so I just lowered the efficiency in brewers friend until the possible OG showed exactly was my reading was. It showed accurate at 60% efficiency.

That's not the way to do it. Measure the actual volume, make sure that it and the actual OG are correct, and then you can believe the mash efficiency number. i.e. the mash efficiency number that results from entering the other two numbers, or the mash efficiency number that you have to enter along with one of the other numbers to get the third. All three are interrelated, and which two you enter and which one is the "answer" depends on what calculator you're using (and whether it's making a prediction or calculating an actual). But bottom line... if you have to fudge an already known (i.e. measured) number to get the answer you were expecting, that's not going to be right.

rethinking my kettle volume remaining before I poured into the fermenter, I’m thinking it was actually less than 1.1 gallons now. When I poured into the fermenter all I really had left in the kettle was troub.

I think you're thinking that because it allows you to see the mash efficiency as what it needed to be to hit 1.050. But again, that's without using the actual volume, i.e. the one you saw with your own eyes before you rethought it.

I recommend reading the Mash Efficiency and Brewhouse Efficiency presentation available here:
http://sonsofalchemy.org/library/
 
That's not the way to do it. Measure the actual volume, make sure that it and the actual OG are correct, and then you can believe the mash efficiency number. i.e. the mash efficiency number that results from entering the other two numbers, or the mash efficiency number that you have to enter along with one of the other numbers to get the third. All three are interrelated, and which two you enter and which one is the "answer" depends on what calculator you're using (and whether it's making a prediction or calculating an actual). But bottom line... if you have to fudge an already known (i.e. measured) number to get the answer you were expecting, that's not going to be right.



I think you're thinking that because it allows you to see the mash efficiency as what it needed to be to hit 1.050. But again, that's without using the actual volume, i.e. the one you saw with your own eyes before you rethought it.

I recommend reading the Mash Efficiency and Brewhouse Efficiency presentation available here:
http://sonsofalchemy.org/library/
Thanks for the recommendation! Will utilize this in the future
 
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