How to lower efficiency

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gnatp2

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I'm getting about 85% efficiency while sparging. I use 1.25 qts/lb of water and typically do 60-90 min mashes at around 148-153. I fly sparge with about 4 gal or so of water until I reach my 7 gal of perboil water volume. On my last sparge, my final runnings were at 1.016

I know this isn't extremely high but I'd like to get down to 75% or so as I hear that there is the potential for tannin extraction and I typically try to make very clean and dry beers so this is an issue.

Should I just stop the sparge early and top off the kettle with pure water? Im wondering if that would help. When doea tannin extraction actually occur? Is is only in the final runnings? Or is there something I'm missing and maybe I'm not at 85% efficiency and miscalculating?

Nate
 
Does the beer taste bad? If not, you have no problem. Your system works well, and you should use the experience to help guide future calculations.
 
I'm getting about 85% efficiency while sparging. I use 1.25 qts/lb of water and typically do 60-90 min mashes at around 148-153. I fly sparge with about 4 gal or so of water until I reach my 7 gal of perboil water volume. On my last sparge, my final runnings were at 1.016

I know this isn't extremely high but I'd like to get down to 75% or so as I hear that there is the potential for tannin extraction and I typically try to make very clean and dry beers so this is an issue.

Should I just stop the sparge early and top off the kettle with pure water? Im wondering if that would help. When doea tannin extraction actually occur? Is is only in the final runnings? Or is there something I'm missing and maybe I'm not at 85% efficiency and miscalculating?

Nate

How are you actually calculating your efficiency? Mash efficiency and brewhouse efficiency are different things.

Tannin extraction is not so much a factor of Mash Efficiency as it is a water temperature / pH and mechanical dispersion concern. Hot sparge, high pH and localized sparge water additions all increase the likelyhood of tannin extraction.

But if you aren't getting tannin bitterness then I wouldn't worry about it at all.
 
Well how are your beers tasting?
If theres nothing wrong with the taste of the brew... 85% eff is only playing to your favor. I could see the possibility of tannin extraction Which I have done and was completely apparent what the issue was.
If you want less eff batch sparge or don't mash for so long, maybe mash at a little higher temp to lower the eff to where you want it. Best of luck
 
On calculating my efficiency, I hope this answers it:

I am calculating my efficiency by calculating my SG of my preboil wort and checking again postboil. I plug my grainbill and these numbers into BeerAlchemy to run my numbers.

Nate
 
what are you losing post-boil to ferementer? I don't know your process; so I'm not being critical....

But for me; I lose ~0.75 gallons from post-boil to fermenter; so it does have an effect on "efficiency"
 
AZ_IPA said:
what are you losing post-boil to ferementer? I don't know your process; so I'm not being critical....

But for me; I lose ~0.75 gallons from post-boil to fermenter; so it does have an effect on "efficiency"

I also lose about 3/4 gal to 1 gal.

I honestly don't care about efficiency in order to bring cost down. So I'm not bothered by losing a gallon of wort here and there. I just want perfect beer. :)
 
I should have been more specific initially with my title: how to lower MASH efficiency.
 
On calculating my efficiency, I hope this answers it:

I am calculating my efficiency by calculating my SG of my preboil wort and checking again postboil. I plug my grainbill and these numbers into BeerAlchemy to run my numbers.

Nate

Nate, You need to know exactly how much liquid volume you have at that time to get an accurate efficiency number. The 85% should apply at either pre-boil (mash efficiency) or Post boil (still mash efficiency, but at a different volume and concentration). BH efficiency isn't until you get into the fermenter and have an accurate volume and OG.
 
Maybe a specific example will help:

8lb pilsner malt
1lb Vienna
4oz carapils

85% efficiency from beeralchemy gives 1.042 preboil for 7 gal and 1.049 postboil for 6 gallons ( I lose 1 gal during my boil)

When I do my SG test with preboil and postboil wort, I'm tying out with those numbers bang on.

Am I doing something wrong on that?
 
Okay - getting to the point...

Why would you want to lower your mash efficiency?

----Seems like he is worried about tannin extraction...

personally 80-85% is about right for a well tuned system. I'd just roll with it unless I was noticing tannin bitterness.

But the cheapest answer is this -- thin your Mash and use less sparge water. you will still run everything through the mash but you will leave more sugar behind.
 
Maybe a specific example will help:

8lb pilsner malt
1lb Vienna
4oz carapils

85% efficiency from beeralchemy gives 1.042 preboil for 7 gal and 1.049 postboil for 6 gallons ( I lose 1 gal during my boil)

When I do my SG test with preboil and postboil wort, I'm tying out with those numbers bang on.

Am I doing something wrong on that?

No you're good. (as long as your volumes are accurate) See my previous post for the answer to your original question...
 
AZ_IPA said:
Okay - getting to the point...

Why would you want to lower your mash efficiency?

Ive read that too high of an efficiency can extract tanins and other unwanted things in the wort.
 
----Seems like he is worried about tannin extraction...

personally 80-85% is about right for a well tuned system. I'd just roll with it unless I was noticing tannin bitterness.

But the cheapest answer is this -- thin your Mash and use less sparge water. you will still run everything through the mash but you will leave more sugar behind.

Can you elaborate on this? Why would a thin mash ( more water/lb of grain) result in less efficiency? I would have thought the opposite.
 
Should have asked but I'm assuming a fly sparge. If you are doing batch it likely won't have much effect at all.

In fly sparge the you are slowly reducing the sugar concentration from the top down. The longer you wash the more sugars you will get out. conversely a short sparge will yield poor sugar extraction. The mash thickness can effect conversion rates, but I'm simplifying the conversion process in the recommendation by saying, within a reasonable range, thick or thin you will get 100% conversion and you will get roughly the same sugar makeup.
 
can you tell us what's wrong with your beer that you want to change? I seriously doubt it has anything to do with your efficiency. Tannins and astringency can happen when your running gets below 1.010, but your say you're above that. I've never heard anyone artificially lower their efficiency to make better beer.
 
can you tell us what's wrong with your beer that you want to change? I seriously doubt it has anything to do with your efficiency. Tannins and astringency can happen when your running gets below 1.010, but your say you're above that. I've never heard anyone artificially lower their efficiency to make better beer.

There may or may not be anything wrong with the beer. I'd like to compare a beer on my system with 70-75% efficiency along with my current 85% efficiency to see if I notice any difference. Obviously there are a bunch of factors other than mash efficiency, but I'd like to see if I notice any improvement with the lower efficiency.

There are people out there who advocate a NO sparge, so that would result in a very low mash efficiency. I don't know if I want to go this far yet, but these people say there is a difference in taste.

I guess maybe this is a better way to look at the issue:
Where does Tanin (or other off flavor) extraction occur during a mash? Is it time? Is it only when it gets below 1.012? Is it based off grain crush? what else?.... If it only happens at lower SG with low pH, then I think my simple answer would be to stop sparging when I get my runnings under X SG and then top off with pure water. But then is there any harm on doing this? Don't know if something magical happens during the mash, where I wouldn't want to add straight water to achieve the correct preboil volume.
 
If you're worried about tannin extraction, why don't you measure the pH of your runnings (especially as you get near the end of the sparge) and determine if you're in the range where that might be a problem? I would certainly try that before just arbitrarily looking for a way to lower my mash efficiency.

But, if you *really* want to lower your efficiency, I would try dropping back from 1.25 qt/lb to something lower, like 0.75 or even 0.50 qt/lb. You could also try milling your grain a little coarser (widen the gap on your mill). Don't get me wrong, I'm with those who say that there is no reason to lower try and lower your efficiency. But if you want to do it, those are some things you might try.

Brian
 
When you say mash efficiency, are you referring to how much sugar is converted during the mash (i.e. conversion efficiency)? Or lauter efficiency?

I think the largest factor affecting tannin extraction is pH, and second is a hot sparge. The reason that you don't want to get below a certain gravity in a sparge is because you aren't going to have the right balance of ions left in the mash to maintain the correct pH. It makes sense if you consider that ideal mash pH is 5.2-5.4, and your water is ~7. If you keep adding water, then your pH is going to creep up. If you're worried about tannins, why don't you get a pH meter and check on your mash/sparge pH values?

Personally, I would want to keep my mash efficiency high and lower the lautering efficiency. You can try to do this by just stopping your fly sparge earlier and adding water to your BK to top up with instead of wort from the tun.
 
If you are worried about tannins, I would recommend taking gravity readings of your runoff. This is super-easy if you have a hydrometer. The rule of thumb is is to stop if you get below 1010.

If 1) your runoff is above 1010, 2) your grains are not overcrushed, and 3) you sparge with water under 170 degrees, you can be very confident that you're not getting tannins from the grains.

Good luck!:mug:
 
I came into this thread thinking it would be like a list of DON'Ts. Boy, was I wrong.
 
When you say mash efficiency, are you referring to how much sugar is converted during the mash (i.e. conversion efficiency)? Or lauter efficiency?

I think the largest factor affecting tannin extraction is pH, and second is a hot sparge. The reason that you don't want to get below a certain gravity in a sparge is because you aren't going to have the right balance of ions left in the mash to maintain the correct pH. It makes sense if you consider that ideal mash pH is 5.2-5.4, and your water is ~7. If you keep adding water, then your pH is going to creep up. If you're worried about tannins, why don't you get a pH meter and check on your mash/sparge pH values?

Personally, I would want to keep my mash efficiency high and lower the lautering efficiency. You can try to do this by just stopping your fly sparge earlier and adding water to your BK to top up with instead of wort from the tun.

Good point in seperating the 2. I'm really not sure what type of mash efficiency to shoot for. I would tend to agree that I probably want high conversion efficiency and that lowering lautering efficiency is the "better" way to lower the mash efficiency. ( i understand that most people think I'm crazy on this issue).

So stopping the lauter early and topping off with pure water to the kettle is fine?

Nate
 
Good point in seperating the 2. I'm really not sure what type of mash efficiency to shoot for. I would tend to agree that I probably want high conversion efficiency and that lowering lautering efficiency is the "better" way to lower the mash efficiency. ( i understand that most people think I'm crazy on this issue).

So stopping the lauter early and topping off with pure water to the kettle is fine?

Nate

I would think it would be fine it is, after all, what people who brew extract do (more or less).

I think that having as close to 100% conversion efficiency is always desirable, because otherwise it seems to me that it could be more inconsistent. Say most people get 90% conversion efficiency on average and you stop yours somewhere before that. It's probably way easier to stop at the top end of conversion efficiency where it plateaus than somewhere in the middle where it would be more rapidly changing. It may also lead to having starch dissolved in your wort, which you obviously don't want in your finished product.

Of course, I may be talking out of my behind here, so someone correct me if I'm wrong :).
 
There are people out there who advocate a NO sparge, so that would result in a very low mash efficiency. I don't know if I want to go this far yet, but these people say there is a difference in taste.

I haven't seen any threads on no sparge on here.. not that HBT is the end all/be all of brewing, but we tend to be an experimental group (ie. no chill, etc).

Anyhow, if you're really concerned it sounds like you have the basis for a good experiment. Tricky part of course would be getting the same OG with the no sparge vs. the sparge. You'll have to use considerably more grain in the no sparge to get the same pre-boil gravity.
 
After I'm finally convinced that batch sparge may be the way to go (I've been doing fly sparge forever), now you gotta go and throw that wrench at me? haha..
 
After I'm finally convinced that batch sparge may be the way to go (I've been doing fly sparge forever), now you gotta go and throw that wrench at me? haha..

I used to double batch sparge, but Denny, Kai, and others presented enough info that I know just do a single sparge. I'd probably no-sparge if I could fit all that water in my MLT...
 
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