Experiment returned confusing results

[cimirie]

So I'm looking for a bit of help here. For as long as I've been AG brewing, I've been following recipes and process recommendations. On my brew rig, I consistently hit the 72-75% range in terms of effeciency. Yesterday, I decided to start experimenting and taking notes to dive deeper into the world of brewing.

I started off to make a blonde ale (OG 1.053). I wanted it thin, so I mashed at 148* for 90 minutes (typically mash in the mid 150s and mash for 60 minutes). Then, I sparged enough to collect 7.5 gallons (typically collect ~6) for a 5 gallon batch. As a result, I boiled for 2 hours, 10 minutes (typcally boil for 60-70 minutes) to reach my desired volume (5gal).

My results were a BHE of 65%. While that isn't awful, it's noticeably lower than my normal, and is close to the lowest I've ever had. The increase in sparge water should have increased my efficiency (I've read). The increase in mash time should have increased my efficiency (I've read). The only thing I'm uncertain about is the mash temp.

I'm not upset about yesterday, as I knew it was an experiment going into the process. I'm just looking for some help sorting out my results.

If it matters, my recipe...


Pale Malt (2 Row) US 5.00 lb
White Wheat Malt 4.00 lb
Caramel/Crystal Malt - 10L 0.50 lb
Wheat, Flaked 0.50 lb
Cara-Pils/Dextrine 0.25 lb

Mash thickness: 1.5 qt/lb

ideas?

 

[BigB]

How often do you use wheat? I always get lower than average efficiency with wheat. You have approximately 50% of the grist as wheat... could explain a lot of it, especially if the wheat was crushed at the same setting as the 2 row.

 

[Clonefarmer]

So I'm looking for a bit of help here. For as long as I've been AG brewing, I've been following recipes and process recommendations. On my brew rig, I consistently hit the 72-75% range in terms of effeciency. Yesterday, I decided to start experimenting and taking notes to dive deeper into the world of brewing.

I started off to make a blonde ale (OG 1.053). I wanted it thin, so I mashed at 148* for 90 minutes (typically mash in the mid 150s and mash for 60 minutes). Then, I sparged enough to collect 7.5 gallons (typically collect ~6) for a 5 gallon batch. As a result, I boiled for 2 hours, 10 minutes (typcally boil for 60-70 minutes) to reach my desired volume (5gal).

My results were a BHE of 65%. While that isn't awful, it's noticeably lower than my normal, and is close to the lowest I've ever had. The increase in sparge water should have increased my efficiency (I've read). The increase in mash time should have increased my efficiency (I've read). The only thing I'm uncertain about is the mash temp.

I'm not upset about yesterday, as I knew it was an experiment going into the process. I'm just looking for some help sorting out my results.

If it matters, my recipe...


Pale Malt (2 Row) US 5.00 lb
White Wheat Malt 4.00 lb
Caramel/Crystal Malt - 10L 0.50 lb
Wheat, Flaked 0.50 lb
Cara-Pils/Dextrine 0.25 lb

Mash thickness: 1.5 qt/lb

ideas?

I would say the extra sparge and thin mash were the cause.

I've noticed my efficiency improve when I mash thicker. In the 1.1 - 1.25 range.

I don't seem to gain all the points back during the boil that were lost due to more sparge volume either.

The mash time and temp shouldn't effect efficiency. Since mash time and temp were in the right range to convert.

 

[electric_beer]

Did you try splitting the sparge water? I've found when I sparge 2x it helps get more sugars then one big sparge.

 

[cimirie]

I would say the extra sparge and thin mash were the cause.

I've noticed my efficiency improve when I mash thicker. In the 1.1 - 1.25 range.

I don't seem to gain all the points back during the boil that were lost due to more sparge volume either.

The mash time and temp shouldn't effect efficiency. Since mash time and temp were in the right range to convert.

I have read that a super thin mash can cause less efficiency, but I've read that "thin" is usually referring to over 2qt/lb, so I thought I was OK. Would an extra .25qt/lb really effect extraction by that much? Does anybody else mash this thin, or should I continue with my traditional 1.5qt/lb going forward?

Extra sparge causes lost effeciency? Everything I've read (until right now) indicates that sparging more INCREASES efficiency (assuming you boil down to correct volume). More "rinse" = more sugar. Honestly not trying to challenge, but I'm curious as to why more sparge would equal less extraction. Thanks for the insight and I look forward to more from you!

Did you try splitting the sparge water? I've found when I sparge 2x it helps get more sugars then one big sparge.

Yes, I split the sparge equally: 2 gallons per sparge: 1st @185, 2nd at 175.

 

[cimirie]

How often do you use wheat? I always get lower than average efficiency with wheat. You have approximately 50% of the grist as wheat... could explain a lot of it, especially if the wheat was crushed at the same setting as the 2 row.

To answer your question, I almost never use wheat. At least, not to that extent. I didn't realize wheat malt was more difficult to extract from than barley. Going forward, should wheat malt be crushed finer or more coarse than barley?

 

[jmo88]

The increase in sparge water should have increased my efficiency (I've read).

No. This is where you went wrong. You can't add more water and expect the sugars to be more concentrated. Adding more water causes more dilution. I think this misunderstanding caused your efficiency loss, though other factors may be at play here as well.

 

[jmo88]

Also, maybe you misunderstood the double sparge theory. Though more rinsing is happening with this method, the volume of water is the same since you would evenly split the sparges.

 

[cimirie]

No. This is where you went wrong. You can't add more water and expect the sugars to be more concentrated. Adding more water causes more dilution. I think this misunderstanding caused your efficiency loss, though other factors may be at play here as well.

If you use more water to sparge, the likelihood of you capturing more sugars increases, but as you point out, your solution is more dilute. If you increase boil time and reduce the volume (increase concentration) to your target (through a longer boil), in theory, you will increase your extraction. Again, according to the theory I've been reading on this site.

Also, maybe you misunderstood the double sparge theory. Though more rinsing is happening with this method, the volume of water is the same since you would evenly split the sparges.

I'll admit, the double sparge method is not something I'm intimately familiar with. I actually learned about it last week. According to my understanding of why it should work, if you sparge in one batch, the likelihood of residual sugar still being left on the grain is X. If instead, you "rinse" twice, that likelihood decreases - even if the total sparge water used is the same (in my case, it wasn't. I used about 1.25 gallons more than I would normally). I have no idea if the double sparge method is worth the time of the extra boil or not (based on this experiment, I'm doubting it), but if I have misunderstood its application, please let me know. Thanks for helping.

 

[BigB]

Wheat malt is smaller than barley malt. So you need to crush it at a tighter setting to get a proper crush. IMHO, the number one reason for low efficiency is usually the crush. If your LHBS crushed the grain for you at their "house crush" setting, then it is probably a wee bit wide to get a proper crush on wheat. When I first used wheat, my efficiency went way down too. I started asking my LHBS to crush the wheat on its own at a tighter setting. My efficiency improved dramatically. Also the enzymes in wheat malt aren't as plentiful as they are in 2 row. Now granted, the available enzymes in 2 row can certainly help in converting the wheat, but with 50% of the grist being wheat, I would expect lower efficiency.

 

[BigB]

As far as double batch sparging goes, you can get a slight increase in efficiency. There was a very informative link on the subject a while back... as I recall either Charlie P or Kaiser did an experiment with no sparge, single batch sparge, double batch sparge, and triple batch sparge. There was an increase in efficiency for each but it was definitely a law of diminishing returns.

EDIT: My bad, it was actually in the Wiki: https://www.homebrewtalk.com/wiki/index.php/Batch_Sparging_Analysis

 

[johngie]

When I use wheat, I'll run it through the mill alone and then again with the other grains.

 

[BigB]

When I use wheat, I'll run it through the mill alone and then again with the other grains.

Good tip.

 

[pkeeler]

So, you got 5 gal. of 1.050?

Do you know the pH of your mash?

 

[cimirie]

So, you got 5 gal. of 1.050?

Do you know the pH of your mash?

It was actually 4.75 g at 1.053 (aimed for 5 gal at 1.054). Total potential should have been 1.077.

No, I didn't get the pH. That will be the next level of notes I take.

 

[Northcalais40]

I have to disagree with clonefarmer and jmo88. If you sparge with 50 gallons of water and boil down to 5 you will not lose efficiency (astringency yes). People batch sparge because it's fast and easy and doesn't lose very much efficiency. When you measure the final runnings of your second sparge it is going to be around 1.020, depending. When fly sparging, if you have enough sparge water, the final runnings will be more like 1.015, depending.

To jmo88, no, adding more water won't make the sugars more concentrated. Adding more water to the mash will dilute its sugars more, so you can run more off. More water means that you rinse the grain more thoroughly, thus higher efficiency.

To cimirie: check out Braukaiser.com. He has a lot of articles and experiments that discuss these exact questions.

 

[jmo88]

More water means that you rinse the grain more thoroughly, thus higher efficiency.

...If you boil off more. I don't think we actually disagree. But for the sake of discussion, make sure you understand what efficiency is referring to. Brewhouse efficiency = lauter efficiency + mash efficiency.

 

[SpanishCastleAle]

...If you boil off more. I don't think we actually disagree. But for the sake of discussion, make sure you understand what efficiency is referring to. Brewhouse efficiency = lauter efficiency + mash efficiency.

Notice how your equation does not have 'boil efficiency' in there? Efficiency is a matter of the gravity at whatever volume you have. So whether you end up with 6 gal or 60 gal in the kettle, if you boil both down to 5 gal and get the same gravity, the efficiency was the same (because you extracted the same amount of sugar either way in my example). How dilute it is doesn't really matter (aside from the extra time to boil it down).

 

[2bluewagons]

^^^+1, BHE calcs end when you have your complete volume of pre-boil wort collected. Doesn't sound like you are, but I have seen folks using volume in the fermenter to calc efficiency, which is problematic. Trub/hop losses, boilovers, etc. can affect the final amount of gravity points from what it was pre-boil.

I haven't tried any experiments like this, but almost always double batch sparge. Get my first runnings, then subtract it from my desired pre-boil volume, divide that into two sparges. Done.

I also agree that it was probably the high percentage of wheat that had the most to do with your efficiency change. If you had sparged your normal amount, efficiency might have even been lower. Wheat malt diastatic power is easily enough to self-convert, so you shouldn't have a problem there. Still should be doing starch tests, although personally I've never had one fail...

 

[brown_dog_us]

I just wanted to add that 1.5 quarts per pound of grain is fine.

 

[cimirie]

^^^+1, BHE calcs end when you have your complete volume of pre-boil wort collected. Doesn't sound like you are, but I have seen folks using volume in the fermenter to calc efficiency, which is problematic. Trub/hop losses, boilovers, etc. can affect the final amount of gravity points from what it was pre-boil.

As I understand it, mash efficiency calcs end when you finish collecting your pre-boil wort. Your BHE calcs are post-boil because BHE is taking your whole brewing process into account. This includes your losses and boilovers.


Thank you to everybody who has given me some insight to my experiment. My takeaways...

-wheat is the devil. Crush it finer than other grains or adjust efficiency expectations.

-double batch sparge can give boost in efficiency, but maybe not as much as expected. Extra sparge volume can help too to a degree.

-neither my particular mash temp or thickness played a large role in efficiency one way or the next.

Sound about right?

 

[jmo88]

As I understand it, mash efficiency calcs end when you finish collecting your pre-boil wort. Your BHE calcs are post-boil because BHE is taking your whole brewing process into account. This includes your losses and boilovers.

It depends on who you ask. Some view it as BHE = lauter eff + mash eff. This is from Braukaiser wiki as well as many other citations. Some take into account efficiency into the fermenter as a part of this as well.

 

[Clonefarmer]

As I understand it, mash efficiency calcs end when you finish collecting your pre-boil wort. Your BHE calcs are post-boil because BHE is taking your whole brewing process into account. This includes your losses and boilovers.


Thank you to everybody who has given me some insight to my experiment. My takeaways...

-wheat is the devil. Crush it finer than other grains or adjust efficiency expectations.

-double batch sparge can give boost in efficiency, but maybe not as much as expected. Extra sparge volume can help too to a degree.

-neither my particular mash temp or thickness played a large role in efficiency one way or the next.

Sound about right?

I've never had issue with wheat malt. I crush it just as fine as the barley malt. If you do crush it finer make sure to use some rice hulls.

I've single batch sparged and now double batch sparge due to space restriction and 10 gallon batches. My efficiency has gone up, but I can't say it's the sparge method or not.

I believe mash thickness plays a role in efficiency. It may be due to my brewing methods, but this is what I experience.

Theories are great, but I'll always go by what I observe.

 

[cimirie]

take into account efficiency into the fermenter as a part of this as well.

I don't know why one wouldn't include this. I would consider my "brewhouse" to be my entire brewday operation. If you're discounting an entire segment's effect on the product, I'm not sure I'd consider that an accurate measure. That's what I was taught by a mentor, anyways, and it makes sense. Thank you for the link and background!

Theories are great, but I'll always go by what I observe.

Good rule of thumb. That's why I'm asking for direction: my observations flew in the face of some established theories!

 

[BigB]

IMHO, you are right and Clone is right. Some brewers don't have any issues with efficiency in wheat, others do... maybe it has to do with the maltster or the other ingredients helping the wheat or the process or all of the above or none of the above. I also believe that mash thickness plays a role, but not a big one. Also I agree that mash temp doesn't play a role in efficiency unless it is too high or too low. Contrary to Clone, I used to double batch sparge and now single batch sparge, and haven't noticed an appreciable difference in efficiency, but I haven't done enough single batch sparges since the switch to make a definitive opinion yet. But whatever you do, KEEP EXPERIMENTING! It will certainly help you zero in on your process and its a heck of a lot of fun along the way.

 

[cimirie]

BigB-

How's that big snow storm affecting you? Made it's way to Shelby yet? (I'm originally from Troy)

 

[SpanishCastleAle]

I don't know why one wouldn't include this. I would consider my "brewhouse" to be my entire brewday operation. If you're discounting an entire segment's effect on the product, I'm not sure I'd consider that an accurate measure. That's what I was taught by a mentor, anyways, and it makes sense. Thank you for the link and background!

I also use the volume/gravity into the fermenter to calculate my BHE because I want to know what my OG will be. I still measure volume/gravity preboil but it's just to make sure I'm 'on track' to hitting my OG in the fermenter (knowing that I'll lose ~2% 'efficiency' in the boil). Seems many, if not most people, use the preboil numbers to calculate efficiency. Either way works.

 

[BigB]

BigB-

How's that big snow storm affecting you? Made it's way to Shelby yet? (I'm originally from Troy)

Not by 7:30 last night.... It didn't come in heavy until after midnight. Although by this morning we only had 5-6 inches, the problem was with the drifting. Its supposed to snow rest of the day however. I've seen a lot worse. The local news pumped up the storm to be more than it was.

 

[jmo88]

I don't know why one wouldn't include this. I would consider my "brewhouse" to be my entire brewday operation. If you're discounting an entire segment's effect on the product, I'm not sure I'd consider that an accurate measure. That's what I was taught by a mentor, anyways, and it makes sense. Thank you for the link and background!

I understand what you are saying. But to me it's a matter of semantics. The word we are trying to nail down here is efficiency. Everything you need to determine how efficient your brewhouse is can be found in your lauter and mash. Let's take a side-by-side comparison of two brewhouses that have perfect mash efficiency but drastically different lauter efficiency. Brewhouse A sparges with 7 gallons of water to achieve a gravity of 1.056 after a 60 minute boil yielding 5 gallons. Brewhouse B sparges with 70 gallons of water to achieve a gravity of 1.058 after a 24 hour boil yielding 5 gallons. Brewhouse B has a higher gravity than Brewhouse A with the same post boil volume. Who was more efficient? I hope you don't believe B was. Beersmith might suggest this is the case though. Just because brewhouse B had a higher potential gravity from his sparge doesn't make him more efficient. Brewhouse B used 10 times as much water and several propane tanks to get there. He is inefficient.

Here is an HBT post from Kai explaining his view of BHE:

On a tangent, brewhouse efficiency should be the same as efficiency into the boiler. Unfortunately Beersmith came up with a different definition and that's what brewers seem to compare these days. In my opinion it should not matter what you leave behind in the kettle when we talk about efficiency. Only mash and lauter matter since losses by leaving wort in the kettle are rather obvious and don't require discussion.

 

[cimirie]

I understand what you are saying. But to me it's a matter of semantics. The word we are trying to nail down here is efficiency. Everything you need to determine how efficient your brewhouse is can be found in your lauter and mash. Let's take a side-by-side comparison of two brewhouses that have perfect mash efficiency but drastically different lauter efficiency. Brewhouse A sparges with 7 gallons of water to achieve a gravity of 1.056 after a 60 minute boil yielding 5 gallons. Brewhouse B sparges with 70 gallons of water to achieve a gravity of 1.058 after a 24 hour boil yielding 5 gallons. Brewhouse B has a higher gravity than Brewhouse A with the same post boil volume. Who was more efficient? I hope you don't believe B was. Beersmith might suggest this is the case though. Just because brewhouse B had a higher potential gravity from his sparge doesn't make him more efficient. Brewhouse B used 10 times as much water and several propane tanks to get there. He is inefficient.

Here is an HBT post from Kai explaining his view of BHE:

I think the term efficiency is what's getting people stuck. In your example, based on the definition of "efficient" your brewer A was far more efficient with resources. But brewhouse efficiency isn't concerned with that. The only item BHE is interested in measuring is how effective you were at getting the sugars out of the grain and into your usable wort. Maybe BHE should be brew house EFFECTIVENESS instead of efficiency.

 

[jmo88]

I think the term efficiency is what's getting people stuck. In your example, based on the definition of "efficient" your brewer A was far more efficient with resources. But brewhouse efficiency isn't concerned with that. The only item BHE is interested in measuring is how effective you were at getting the sugars out of the grain and into your usable wort. Maybe BHE should be brew house EFFECTIVENESS instead of efficiency.

That's right. You can't have a terribly dilute lauter which gives you poor efficiency and claim to be an efficient brewer by boiling longer. Boiling doesn't deserve to be in the BHE equation. You can't be an efficient boiler – it doesn't make sense. Boiling efficiency doesn't really exist.

 

[SpanishCastleAle]

The word 'efficiency' in the context we are using it doesn't necessarily mean 'efficient', it means 'innefficient' just as much as it means 'efficient'. 10% BHE isn't 'efficient' by any stretch but it's still called 'efficiency'.

 

[cimirie]

That's right. You can't have a terribly dilute lauter which gives you poor efficiency and claim to be an efficient brewer by boiling longer. Boiling doesn't deserve to be in the BHE equation. You can't be an efficient boiler – it doesn't make sense. Boiling efficiency doesn't really exist.

By the same token, boiling is the equalizer. You have to have it in the equation. If you're trying to measure how well you pulled sugar out of the grain, it's not accurate to include only your pre-boil.

Efficiency deals with total sugar extracted, not sugar extracted by volume. If you used 100 gallons to sparge 10 lbs of grain, but pulled 95% of the sugars out, that was very effective (which is all BHE is concerned with) without being academically "efficient."

The reason you need to use post boil numbers is that the formula compares your actual numbers to a theoretical yield, which is based on a particular batch size. You need to have a comparable batch to determine %sugar yield which is BHE.

 

[jmo88]

By the same token, boiling is the equalizer. You have to have it in the equation. If you're trying to measure how well you pulled sugar out of the grain, it's not accurate to include only your pre-boil.

Efficiency deals with total sugar extracted, not sugar extracted by volume. If you used 100 gallons to sparge 10 lbs of grain, but pulled 95% of the sugars out, that was very effective (which is all BHE is concerned with) without being academically "efficient."

The reason you need to use post boil numbers is that the formula compares your actual numbers to a theoretical yield, which is based on a particular batch size. You need to have a comparable batch to determine %sugar yield which is BHE.

Well, this is the dichotomy. There are obviously two sides to it, and those on each side find faults in the other. Of course, those that see BHE = lauter eff+ mash eff are not ignoring the effect of boil and transfer on the OG. But, as soon as you try to include boiling and transfer to the fermenter into the equation, I feel that you ignore the importance of lauter efficiency.

Just in case you haven't read some of the concepts regarding the above equation. Check out this page

 

[BigB]

For what its worth, to me it appears that you guys actually agree but are defining two separate measures of efficiency. If it matters, my reference to efficiency regarding the wort was a reference to potential yield vs actual yield, pre-boil. I measure efficiency the way Palmer Does: ((potential yield per pound x # of pounds)/volume collected)/OG pre-boil. At that point I can tell if I'm going to hit my post-boil OG or not and will sometimes adjust accordingly. I'm personally not concerned with my efficiency post-boil because the only thing I could change would be how long I boil(EDIT: I suppose I could change the flame to change how vigorously it boils-but again, that is not important to me personally). There is certainly nothing wrong with looking at the entire process though.

 

[cimirie]

jmo88-

Awesome link. The article is a great source for information. I've seen things like that before, but nothing so in depth. Thanks.

One quote from it that sums up what I'm trying to say much better than I've been able to say myself:

"it is obvious that each additional sparge step (run-off) will bring more of the extract from the mash into the boil kettle and thus increase the efficiency."

It goes on to talk about diminishing returns of additional sparges. Thanks for the discussion this afternoon and the insight! It's appreciated.

 

[cimirie]

For what its worth, to me it appears that you guys actually agree but are defining two separate measures of efficiency. If it matters, my reference to efficiency regarding the wort was a reference to potential yield vs actual yield, pre-boil. I measure efficiency the way Palmer Does: ((potential yield per pound x # of pounds)/volume collected)/OG pre-boil. At that point I can tell if I'm going to hit my post-boil OG or not and will sometimes adjust accordingly. I'm personally not concerned with my efficiency post-boil because the only thing I could change would be how long I boil(EDIT: I suppose I could change the flame to change how vigorously it boils-but again, that is not important to me personally). There is certainly nothing wrong with looking at the entire process though.

I guess the way Palmer defines efficiency is more useful while in-process because as you say, it may allow you to make changes on the fly. I've always used efficiency as a way to measure my performance at the end of the day, not as a tool in-process. Something to think about.