Brewing: Low Efficiency Desirable Benefits Possible? Can Tanking Efficiency INCREASE Flavor?

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GirthySquirt

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Main Question: Can I lower my brew-house efficiency purposefully to enable using a massive grain bill and get more flavor in my final product? Can low brew-house efficiency actually improve beer flavor, body, and mouthfeel in some scenarios because low efficiency implies more grain is being used, which actually contributes more flavor and other molecules beyond sugar to the beer compared to if less grain and higher efficiency was used? More grain being used implies more original "grainy-flavored" precursor molecules available to donate into the wort, as well as more protein and other adjunct molecules beyond just our typical five or so fermentable sugars that could be desirable in a finished beer.

If brew-house efficiency looks at sugar as the main focus, what about efficiencies for these other important flavor and body-oriented molecules (is there a protein efficiency that could be measured)? What about a "flavor" contribution/efficiency? Are all these different molecule efficiencies somehow inexplicably intertwined, or is sugar extraction not the entire story for how our lone-number "brew-house efficiency" parameter effects flavor and final product.

Experiment: Imagine two scenarios that each make a 5% ABV beer for a 5 gallon home-brewed batch:
1. You have one brew-day/grain bill that is 14lbs of Pilsner malt with 45% brew-house efficiency with an OG of 1.048.
2. You have a second brew-day/grain bill that is 7lbs of Pilsner malt with 90% brew-house efficiency with an OG of 1.048.

Assuming brew-house efficiency is a principally a measure of sugars in the fermenter water (using a hydrometer-based measurement - which perhaps is not always the best assumption, especially for a scenario like this) and you really could get these exact efficiencies and starting gravities for both these grain bills, both beers hypothetically ferment out (with the same yeast) to roughly the same final gravity of about 1.010 with a nice Kölsch yeast and about 5% ABV. Will there be perceivable differences between the beers? Will the more-grain beer have more flavor or will they be imperceptibly the same? Are there any side-by-side experiments anyone knows of where brew-house efficiency (and the corresponding grain bill) are being varied to obtain two starting worts of comparable starting gravity to ferment?

As brewer's we often think of "brewhouse efficiency" (and sugar) as our target - how can I absolutely maximize what percent of sugar I get out of my grain bill and into my fermenter. What about proteins or other precursors? Logically, at first it seems like high brew-house efficiency may indicate high amounts of protein for example, but perhaps this is not strictly true; we have some saccharification efficiency from our beta/alpha enzymes but is protein extraction efficiency directly related to this sugar extraction efficiency? What if protein is easily donated to the wort, and we capture 100% of the protein we put in every time? Does more grain always mean more protein and more body if we add more grain? Even if we don't have 100% protein efficiency, it seems logical to also expect that no matter what, more input grain yields more output protein if every other efficiency factor remains roughly the same. Flavor contribution (where no enzymatic process is necessary to release the flavor molecules) is another potential controversy, as it seems highly intuitive that more grain should yield more flavor contribution, yet hardly anyone seems to be advocating using as much grain as you can to improve flavor.

In summary: I have made a number of beers on my Anvil Foundry system where if I am lazy I can get around 55% brew-house efficiency going spargeless doing no work and using a larger grain gill, or I can pull out all the stops and get roughly 77% brew-house efficiency with sparging, recirculation, long-mashing, and heavy stirring/grain agitation. When I anticipate going all-out I make my grain bill smaller to achieve a similar final product with regards to ABV, but I have noticed my higher-efficiency beers I brew do not have as much body or flavor to them as their lazy, low-efficiency counterparts, leading me to wonder about efficiency effects. Anecdotally, many local brewers I have talked to in the USA are always chasing extremely high brew-house efficiency - I'm talking 90% and greater. Coincidentally, many american beers are light-bodied and less flavorful in some regards to their European and other counterparts. Could low efficiency be another key player to great flavor, or are other processing parameters really the star of the show elevating a beer from flavorful greatness to true excellence?

TLDR: Can I tank my brew-house efficiency purposefully to enable using a massive grain bill and get more flavor?

Any input and experience with this is greatly appreciated!
 
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I think this is quite an interesting line of inquiry. I certainly don't have enough experience to speak on the topic theoretically, but I'd love to see some empirical results.
 
Working on theory here...

With a low conversion efficiency, the likelihood is that it is due to insufficient gelatinization. The water isn't getting into the grain fully. If it's not getting in there to access carbs/sugar, it's not getting in there to access flavor either.

With full conversion and low lauter efficiency, the sugar has been accessed fully and so has the flavor, it's just not getting into the kettle. Again, the same thing that is affecting carbs/sugar into the kettle will affect how much flavor gets there too.

With brewhouse efficiency (assuming full conversion and decent lautering), the wort in the kettle is what it is. An efficiency hog of a transfer won't affect gravity nor flavor.

In theory.
 
Im now experiencing with party gyle, and the second beer (the one from the sparged grains) always gets some problem with head formation and retention, so maybe this is an indication that yes, we get more of the proteins, even with sugars left behind.
 
Comparing a 2nd running to its 1st is not the same as comparing two batches of varying efficiencies*.

*OP, mind specifying what you actually mean by 'efficiency'? Conversion, lauter, mash, brewhouse?
 
My gut tells me with really good efficiency and the right amount of grain and water you will get all of the good stuff out of the grain and that includes all of the flavor compounds. For mouthfeel it can be tweeked easily enough with other methods than reducing the efficiency. I'm no expert, but that makes sense to me. :mug:

Edit: I suppose you could always partygyle the 1/2 spent grains and get a second 5% beer, or add some steeped adjuncts and make a totally different second beer. A Guiness style dry stout might be a good option for the second beer.
 
Im now experiencing with party gyle, and the second beer (the one from the sparged grains) always gets some problem with head formation and retention, so maybe this is an indication that yes, we get more of the proteins, even with sugars left behind.

OT:

Traditional British parti-gyling involves more than 1st running makes a strong beer, 2nd running makes a small beer.

Once the two runnings are pulled, they are boiled individually. Once boiled, they are blended to create the intended worts for fermentation. The big beer might be 80:20 1st:2nd worts. The small beer might be 20:80 1st:2nd worts. This gets some of the 1st running goodness into the small beer.
 
OT:

Traditional British parti-gyling involves more than 1st running makes a strong beer, 2nd running makes a small beer.

Once the two runnings are pulled, they are boiled individually. Once boiled, they are blended to create the intended worts for fermentation. The big beer might be 80:20 1st:2nd worts. The small beer might be 20:80 1st:2nd worts. This gets some of the 1st running goodness into the small beer.
Yes, i read about that, thanks for the info anyway. For now, im just doing it for the experience, and to extract some more beer to experiment on.
 
Working on theory here...

With a low conversion efficiency, the likelihood is that it is due to insufficient gelatinization. The water isn't getting into the grain fully. If it's not getting in there to access carbs/sugar, it's not getting in there to access flavor either.

With full conversion and low lauter efficiency, the sugar has been accessed fully and so has the flavor, it's just not getting into the kettle. Again, the same thing that is affecting carbs/sugar into the kettle will affect how much flavor gets there too.

With brewhouse efficiency (assuming full conversion and decent lautering), the wort in the kettle is what it is. An efficiency hog of a transfer won't affect gravity nor flavor.

In theory.
I think this is a great response. Intuitively it makes sense to me that with higher conversion efficiency means we get more of everything out of the exact same grains (more sugar, more protein, more flavor, etc.). This really makes sense if the grain is completely homogeneous; as you leach more and more "stuff" out of the grain itself, you uniformly obtain more of each molecule. If your kernel has stuff locked away that your water never accesses, and you get lower conversion efficiency of everything equally.

But to my knowledge the grain kernels are NOT homogeneous, whereby the starch is locked away at the center of the kernel in the endosperm and the protein is easily accessible at the exterior of the kernel in the aleurone. This to me indicates that the efficiency of sugar conversion is not necessarily the same as the efficiency of getting proteins into the wort, and generally-speaking proteins are the first and easiest thing to dissolve into your wort since they compose the majority of the surface area of the milled kernel.

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Extremely fine milling would make it so there is a lot more starch "surface area" (and give high efficiency of both by evening the playing field) but for the average brewer with normal kernel milling it seems like proteins are more easily contributed to the wort (since they are at the kernel surface) but starch is harder to access (locked in the center).

Is there any chance that assuming protein conversion/extraction efficiency and sugar conversion/extraction efficiency are principally the same thing is actually not a great assumption? It leads me to think if yes there could be something to the "more grain more flavor" idea...

Im now experiencing with party gyle, and the second beer (the one from the sparged grains) always gets some problem with head formation and retention, so maybe this is an indication that yes, we get more of the proteins, even with sugars left behind.

I think the parti-gyling thing is actually a great point, but to the opposite less-flavor effect. I can't really access/convert all the sugar in one round, so I do a secondary mash with the same grains. If my first go-around I did extract almost all the protein (and other molecules) it makes sense that the parti-gyling second runnings are extremely light-bodied and potentially less flavorful. Just my three cents...
 
I think the parti-gyling thing is actually a great point, but to the opposite less-flavor effect. I can't really access/convert all the sugar in one round, so I do a secondary mash with the same grains. If my first go-around I did extract almost all the protein (and other molecules) it makes sense that the parti-gyling second runnings are extremely light-bodied and potentially less flavorful. Just my three cents...

Small nitpick...

The second running in parti-gyling isn't from a second mash. Just a sparge. It's not about converting more starch into sugar, just rinsing the existing wort from the grain bed with fresh water.
 
I brew lower ABV session strength versions of various beer styles. At first I was getting thin, watery beers. To resolve this I have purposefully opened my mill gap therefore use more grain to get a desired OG, use a full volume no sparge 90 min mash, and limit myself to 30 min boils. I like the results.

I would agree there’s got to be more to the mash extract than sugar. Other constituents must be present because I get beautiful foam, lacing, body, etc. whereas before I took these steps I did not.
 
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And as another anecdote...

I brew British bitters at ~1.040 with 92% mash efficiency. 5% wheat, 10% invert, 0% crystal. Ground very fine, ~152°, 60m.

Body, foam, lacing, etc. are as desired.
 
Main Question: Can I lower my brew-house efficiency purposefully to enable using a massive grain bill and get more flavor in my final product? Can low brew-house efficiency actually improve beer flavor, body, and mouthfeel in some scenarios because low efficiency implies more grain is being used, which actually contributes more flavor and other molecules beyond sugar to the beer compared to if less grain and higher efficiency was used? More grain being used implies more original "grainy-flavored" precursor molecules available to donate into the wort, as well as more protein and other adjunct molecules beyond just our typical five or so fermentable sugars that could be desirable in a finished beer.

If brew-house efficiency looks at sugar as the main focus, what about efficiencies for these other important flavor and body-oriented molecules (is there a protein efficiency that could be measured)? What about a "flavor" contribution/efficiency? Are all these different molecule efficiencies somehow inexplicably intertwined, or is sugar extraction not the entire story for how our lone-number "brew-house efficiency" parameter effects flavor and final product.

Experiment: Imagine two scenarios that each make a 5% ABV beer for a 5 gallon home-brewed batch:
1. You have one brew-day/grain bill that is 14lbs of Pilsner malt with 45% brew-house efficiency with an OG of 1.048.
2. You have a second brew-day/grain bill that is 7lbs of Pilsner malt with 90% brew-house efficiency with an OG of 1.048.

Assuming brew-house efficiency is a principally a measure of sugars in the water (using a hydrometer-based measurement - which perhaps is not always the best assumption, especially for a scenario like this) and you really could get these exact efficiencies and starting gravities for both these grain bills, both beers hypothetically ferment out (with the same yeast) to roughly the same final gravity of about 1.010 with a nice Kölsch yeast and about 5% ABV. Will there be perceivable differences between the beers? Will the more-grain beer have more flavor or will they be imperceptibly the same? Are there any side by side experiments anyone knows of where brew-house efficiency (and the corresponding grain bill) are being varied to obtain two starting worts of comparable starting gravity to ferment?

As brewer's we often think of "brewhouse efficiency" (and sugar) as our target - how can I absolutely maximize what percent of sugar I get out of my grain bill and into my fermenter. What about proteins or other precursors? Logically, at first it seems like high brew-house efficiency may indicate high amounts of protein for example, but perhaps this is not strictly true; we have some saccharification efficiency from our beta/alpha enzymes but is protein extraction efficiency directly related to this sugar extraction efficiency? What if protein is easily donated to the wort, and we capture 100% of the protein we put in every time? Does more grain always mean more protein and more body if we add more grain? Even if we don't have 100% protein efficiency, it seems logical to also expect that no matter what more input grain yields more output protein if every other efficiency factor remains roughly the same. Flavor contribution (where no enzymatic process is necessary to release the flavor molecules) is another potential controversy, as it seems highly intuitive that more grain should yield more flavor contribution, yet hardly anyone seems to be advocating using as much grain as you can to improve flavor.

In summary: I have made a number of beers on my Anvil Foundry system where if I am lazy I can get around 55% brew-house efficiency going spargeless doing no work and using a FAT grain gill, or I can pull out all the stops and get roughly 77% efficiency with sparging, recirculation, long-mashing, and heavy stirring/grain agitation. When I anticipate going all-out I make my grain bill smaller to achieve a similar final product with regards to ABV, but I have noticed my higher-efficiency beers I brew do not have as much body or flavor to them as their lazy, low-efficiency counterparts, leading me to wonder about efficiency effects. Anecdotally, many local brewers I have talked to in the USA are always chasing extremely high brew-house efficiency - I'm talking 90% and greater. Coincidentally, many american beers are light-bodied and less flavorful in some regards to their European and other counterparts. Could low efficiency be another key player to great flavor, or are other processing parameters really the star of the show elevating a beer from flavorful greatness to true excellence?

TLDR: Can I tank my brew-house efficiency purposefully to enable using a massive grain bill and get more flavor?

Any input and experience with this is greatly appreciated!
First off, efficiency does not just account for sugar, but rather all of the "Extract" in the wort. "Extract" consists of about 88 - 90% carbohydrates (mono, di, and tri-saccharides [mostly fermentable], dextrins [non-fermentable], and soluble starch [non-fermentable]), most of the balance is protein, and then small amounts of many, many compounds. Everything that goes into solution from the grain increases the SG of the wort, and is part of the extract. Efficiency doesn't tell you anything about the ratio of the different components in the extract, nor the molecular weight distribution of the carbohydrates (which determines fermentability.) When talking about efficiency, we tend to get a little sloppy and talk like it is just about sugar. One reason we do this is it's less confusing to newbies, who usually need to learn nuance incrementally.

Second, brewhouse efficiency is not the best metric to use for your purposes. The important efficiencies are "Conversion Efficiency," which measures how much of the potential extract from the grain actually makes it into solution in the wort during the mash, and "Lauter Efficiency," which measures how much of the extract that was created during the mash makes it into the boil kettle. "Mash Efficiency" is Conversion Efficiency times Lauter Efficiency. "Brewhouse Efficiency" is equal to Mash Efficiency times "Fermenter Transfer Efficiency," and

Fermenter Transfer Efficiency = Volume in Fermenter / Post-Boil Volume in BK​
Since transfer efficiency does not affect the wort composition in any way, it should be left out of this discussion. And, since a major factor in brewhouse efficiency is transfer efficiency, it is not the appropriate metric for this discussion either.

The composition of the extract is not affected by lauter efficiency either, assuming your wort is fully homogenized prior to mash run-off. Lauter efficiency will vary with the concentration of extract in the wort, and higher efficiency usually means lower extract concentration in the wort (i.e. lower SG wort.)

So, the most appropriate efficiency for this discussion would appear to be conversion efficiency, and it would only matter if the rate of starch conversion is different from the rate of extraction for non-carbohydrate wort components.

In order for sacrificing conversion efficiency to improve flavor, the rate of extraction for the flavor components of wort would have to be faster than the rate of starch conversion, otherwise conversion would be done before all of the flavor compounds are brought into solution. @RM-MN has found the opposite to be true - conversion completes before all of the flavor compounds have been extracted.

Now @RM-MN does BIAB, and uses an extremely fine crush, which allows starch conversion to complete in 10 - 15 minutes, but mashes for longer in order to get more flavor compounds dissolved. With coarser crushes starch conversion (in particular the gelatinization step) takes longer, and flavor compounds not embedded in the endosperm with the starch, might then finish dissolving before starch conversion is complete. For this latter case, sacrificing conversion efficiency might allow the wort to have a higher ratio of flavor components to carbohydrate.

Brew on :mug:
 
Can low brew-house efficiency actually improve beer flavor, body, and mouthfeel in some scenarios
For me, the most relevant lower-efficiency scenario is stopping the sparge "early", so that some sugars and other wort components are left behind. Other things equal, this means less boiling, which itself could make a flavor/body/mouthfeel difference. My experience (shifting my focus away from efficiency) does not confirm this.

However, a somewhat coarser grind - another lower-efficiency scenario - could reasonably be expected to make some difference in the resulting beer. But I expect other factors to outweigh the effects of finer-vs.- coarser grind - again, other things equal.

In the other direction (higher efficiency), over-sparging could extract astringent flavors. Avoiding that should "improve beer flavor..." However, accidental over-sparging events (with consequent long boil) have not led to obvious issues, so I'm still unable to match @GirthySquirt's hypothesis with my brewing (and consequent drinking🍺) experience.

Cheers!
 
In order for sacrificing conversion efficiency to improve flavor, the rate of extraction for the flavor components of wort would have to be faster than the rate of starch conversion, otherwise conversion would be done before all of the flavor compounds are brought into solution. @RM-MN has found the opposite to be true - conversion completes before all of the flavor compounds have been extracted.

Now @RM-MN does BIAB, and uses an extremely fine crush, which allows starch conversion to complete in 10 - 15 minutes, but mashes for longer in order to get more flavor compounds dissolved. With coarser crushes starch conversion (in particular the gelatinization step) takes longer, and flavor compounds not embedded in the endosperm with the starch, might then finish dissolving before starch conversion is complete. For this latter case, sacrificing conversion efficiency might allow the wort to have a higher ratio of flavor components to carbohydrate.

Brew on :mug:

doug293cz, this is an excellent response, and this sentence in particular really got me thinking:

"In order for sacrificing conversion efficiency to improve flavor, the rate of extraction for the flavor components of wort would have to be faster than the rate of starch conversion, otherwise conversion would be done before all of the flavor compounds are brought into solution".

My original question really boils down to "is it possible to have different overall maximum conversion/extraction efficiencies of protein, flavor compounds, and sugars for a given system, depending on your process"? If so, is it possible that you can change your process/mash efficiency and have significantly less sugar conversion/extraction while still having relatively high protein or flavor extraction?

I think of my conundrum being more about maximum possible conversion/extraction discrepancies between different compounds and less about the specific rates of conversion/extraction discrepancy, whereby I am assuming you are not rate-limited and you can mash however long you need to obtain your absolute maximum efficiency for every single compound.

I think my hypothesis is best explained by my simple hypothetical experiment below:

----------------------------------------------------------------------------------
Hypothetical Brew Days: 2 Processes, 2 Efficiencies (Low/High), 2 Different Conversion Ratios
Lets say I break out my high-efficiency process and gear. I'm sparging, I'm recirculating, I'm agitating my grains manually, really just giving it the works. Hypothetically, say I have some "special" barley that is 90% sugar and 10% protein by weight, and all of this mass is totally convertible (not realistic, but simplifies my example). I have very high conversion efficiencies, but they are NOT the same for every molecule - 90% sugar conversion/extraction and 95% protein conversion/extraction. Let's assume for simplicity's sake right now that my conversion efficiency stays roughly the same for this process/equipment regardless of how much grain I use (maybe a bad idea).

If I put 1000 grams of my special barley in, I wind up with a sugar content of (grain_mass*sugar_portion_in_grain*sugar_conversion_efficiency) = 1000*0.9*0.9 = 810 grams of sugar in solution. I also have 1000*0.1*0.95 = 95 grams of protein in solution - 905 grams added total. Let's say I put this extract in a 20L batch - I add 905g of sugar and protein to my 20,000 grams (20L) of water to make my wort. Keeping my 20L volume the same and adding the extract I find I have a OG measurement of ~1.045.

Now I brew again and I'm lazy; I can't be arsed to try today - I go spargeless and don't lift but half a finger the whole mash and start with my same same special barley that is completely convertible 90% sugar and 10% protein by weight, but now I get molecular conversion efficiencies that are a bit different and not scaled down the same: 70% sugar conversion/extraction and 90% protein conversion/extraction. Note that my less-efficiency mash does not linearly scale down both the efficiencies - they scale differently (hypothetically), whereby I still get really good protein conversion but not so great sugar conversion. I believe this could be possible, especially at the home-brew scale, when you have not-so-finely crushed grain. Principally, I think this effect is at the core of my hypothesis.

With these new, poorer efficiencies if I put 1000 grams of barley in, I wind up with 1000*0.9*0.7 = 630 grams of sugar in solution and 1000*0.1*0.9 = 90 grams of protein in solution. But I still want my same beer, though! So I adjust my grain bill accordingly. I know 1000g of barley gives me 720g total of extract for this particular poor-efficiency setting, so I scale up by a factor of (905/720) to start with 1257 grams of barley to get me to my same 1.045 OG.

Now I put 1257 grams of barley in, I wind up with 1257*0.9*0.7 = 791.9 grams of sugar in solution and 1257*0.1*0.9 = 113.1 grams of protein in solution. I still have 905 grams added in for lazy-beer, but check out my low efficiency beer - less sugar, more protein, same OG. In fact, I have increased the protein in solution by 19% for the low efficiency beer compared to the high efficiency beer. Concomitantly, I have lessened the amount of sugar in my 1.045 OG beer by 2.2%. Basically, I'm taking advantage of the efficiency discrepancy and trading sugar for protein for the exact same OG beer.

----------------------------------------------------------------------------------

Could this same variation-effect happen for molecules like flavor compounds as well? Can we really say that changing conversion efficiency of sugar linearly scales down the conversion efficiency of all other molecules?

Back to doug293cz's original comment: It seems like in a very short-length mash scenario, this rate-limiting effect would be really important to ensure you get the flavor you need - I believe it really makes sense to me that for a very short mash you could have very different rates of molecular extraction of different compounds from the grain and extract one compound so quickly (say, sugar) that you need to wait for the others to "catch up" to get a balanced beer, whereby this could go either way depending on which is molecule's extraction is quicker and could be system/process/ingredient related.

What about if you are not time-limited, and rates become non-influential? Say you can mash for hours, or at least until the point that you have done every last bit of conversion/extraction you can with your particular system. Especially for those of us getting lower efficiency, it seems to me that it could be possible to get different efficiency of protein conversion/extraction versus efficiency of sugar conversion/extraction depending on your specific process and grain milling.

If there is a significant discrepancy in the maximum possible raw conversion/extraction efficiency of proteins/flavor compounds versus sugar on a particular system with different procedures, could there be some merit to attempting to modulate your conversion efficiency to effect the final balance of the final wort concentration like in the hypothetical example above?

Also, I like focusing on the conversion efficiency specifically here, as like you said that is really where this conundrum could potentially come into play and have effects that are, potentially, influential.
 
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The practical example of this is full volume, no sparge mashing. Lower extract is a byproduct of not sparging and I did notice an improvement in my beers several years ago when I stopped sparging. I attribute that improvement primarily to the ease of achieving and maintaining a wanted lower mash pH whereas sparging is usually a moving target that can lead to tannin extraction if you're not paying attention.
 
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