Effects of different mash/sparge temps?

[Gtrman13]

I'm somewhat new to allgrain brewing (done about 5 batches) and have always aimed for a mash temp of 150-153 and a sparge temp of 167-170. I've heard of some folks mashing at temperatures from the upper 150s to the lower 140s and different sparge temps as well. What is the reasoning behind using different temperatures? Just curious, thanks!

 

[Justibone]

Different mash temps give different length sugar chains, which affects how much of the malt your yeast can eat. Higher temps (155 or so) give more body, lower temps (145 or so) give more "crisp" flavor, IIRC. It has to do with the relative activity of alpha-amylase versus beta-amylase, I believe.

I'm no expert, though!

 

[payton34]

great question. i brewed a cane and ebel clone and overshot my mash temp. i usuallymash at 154 but this time it was at 158. it was real cold out and i thought i might lose some temp but i didn't. don't know how it will turn out

 

[maida7]

Mash temp is very important and can greatly effect the fermentabilty and body or mouth feel of the beer. There are 2 mahjor enzymes at work to break down the long chain starches into simpler sugars for the yeast to ferment. Yeast can't eat the more complex sugars (dextrines) if they are allowed to remain the dextrines will add body and posibly sweetness to the beer. A beer low in dextrines will be more fermentable, have a lower finishing gravity, a lighter body and a dry finish.

The Low temps 147-152 will produce less dextrines and more simple sugars. light body and dry finish

High temps 156-166 will produce more dextrtines and less simple sugars. Heavy body and (sometimes) a sweeter finish.

153-155 is the mid range.

 

[Justibone]

If your temp goes too high, you inactivate the enzymes permanently, so you get incomplete conversion... i.e., fewer fermentables.

 

[maida7]

Also the enzymes work faster at the higher temps and slower at the lower temps. When I mash at <150 I let it go for 90 min. If I mash at >162 I only go for 45 min. anything in between and I do a typical 60 min rest.

For the sparge the hotter temps will help dissolve the sugars and better rinse the grain. BUT do not exceed 170F. Above 170 you risk tannin extraction and that will make your beer astringent.

 

[Gtrman13]

Is it possible to start mashing at, say, 148 and then gradually move up to 156 in an attempt to get all of the fermentable sugars out while still getting plenty of body in the beer?

I like knowing this! I have the feeling this stuff is gonna make a big difference in my brewing!

 

[Gtrman13]

Also, if higher temps produce more dextrines which can't be eaten by the yeasties and I to assume this would give me a lower OG?

 

[Justibone]

Is it possible to start mashing at, say, 148 and then gradually move up to 156 in an attempt to get all of the fermentable sugars out while still getting plenty of body in the beer?

This is kinda why it's recommended to mash at about 153F. You get some of both.

 

[Justibone]

Also, if higher temps produce more dextrines which can't be eaten by the yeasties and I to assume this would give me a lower OG?

Not necessarily, I believe dextrines are measured in gravity readings, IIRC.

If you have incomplete conversion due to low temp and too short of a mash, then you would have lower gravity for certain.

 

[maida7]

Is it possible to start mashing at, say, 148 and then gradually move up to 156 in an attempt to get all of the fermentable sugars out while still getting plenty of body in the beer?

I like knowing this! I have the feeling this stuff is gonna make a big difference in my brewing!

Not really. Assuming you get full conversion. The temps control the balance between dextrines and simple sugars. If your changing the temps (step mash) then the results will depend on how long you leave the mash at what temp(s).

There is also a much lower temp where protein enzymes are active. But this step is not needed for modern malts.

 

[Yooper]

Also, if higher temps produce more dextrines which can't be eaten by the yeasties and I to assume this would give me a lower OG?

No. The starches still convert to sugars, but they are less fermentable. So, the OG would be the same as there is the same amount of sugars. But the FG will be higher as a result of the higher temp mash, and the body of the beer will be "thicker".

 

[maida7]

Also, if higher temps produce more dextrines which can't be eaten by the yeasties and I to assume this would give me a lower OG?

Assuming you get full conversion the original gravity (OG) should be the same regardless of mash temp. But fermentability will vary. You'd expect a low temp mash to be more fermentable (more simple sugars) and result in a lower finish gravity (FG). A high mash temp would produce a higher FG.

There lotsa other factors that will effect your OG like mash and lauter efficiency, crush, mash pH, etc... But that's a whole nother topic.

 

[cobolstinks]

what about sparge temps? Ive heard that you want your sparge temp around 165 F, so depending on the original mash temp, I sometimes sparge in with 180 degree F water to bring the total temp to around 165, is this correct? Why is it that much higher than mash in temps?

 

[maida7]

what about sparge temps? Ive heard that you want your sparge temp around 165 F, so depending on the original mash temp, I sometimes sparge in with 180 degree F water to bring the total temp to around 165, is this correct? Why is it that much higher than mash in temps?

Yes that is correct you want to get the sparge up close to 170F. Your no longer working to get the enzymes at proper temps. For the sparge the hotter temps will help dissolve the sugars and better rinse the grain. BUT do not exceed 170F. Above 170 you risk tannin extraction and that will make your beer astringent.

 

[cactusgarrett]

There is some argument, however, that a 170°F sparge isn't integral to a more efficient sparge. Kai did some work on this, and some searching can find it. But for advising someone new to the process, i'll bite my tongue at this time.

 

[Yooper]

There is some argument, however, that a 170°F sparge isn't integral to a more efficient sparge. Kai did some work on this, and some searching can find it. But for advising someone new to the process, i'll bite my tongue at this time.

You're correct! I can't remember all of the details but Kai found that even a cold water sparge can be just as efficient.

The reason we "pick" 165-170 is because that's hot enough to stop the conversion of the enzymes, to "denature" them and as such to preserve the mash profile. It's also a good temperature because sugars are more fluid in the hotter liquid, but not hot enough to risk tannin extraction.

I've had some batches were adding near boiling water for my sparge just didn't raise the grain bed temperature up to 170 but it turned out fine anyway, of course!

 

[cactusgarrett]

Is it possible to start mashing at, say, 148 and then gradually move up to 156 in an attempt to get all of the fermentable sugars out while still getting plenty of body in the beer?

If you look at certain recipes, they utilize what is known as a double infusion mash to address what you're asking. Here they initially strike to attain a beta amylase temp for, say 30min, then add a certain amount of water at a certain temp to their MLT to attain an alpha amylase temp for another 30min.

The alternative (for people who are set up to do so) is to directly fire the MLT, thus avoiding infusion water additions.

 

[Yooper]

If you look at certain recipes, they utilize what is known as a double infusion mash to address what you're asking. Here they initially strike to attain a beta amylase temp for, say 30min, then add a certain amount of water at a certain temp to their MLT to attain an alpha amylase temp for another 30min.

The alternative (for people who are set up to do so) is to directly fire the MLT, thus avoiding infusion water additions.

Or of course HERMS and RIMS!

 

[cactusgarrett]

I've had some batches were adding near boiling water for my sparge just didn't raise the grain bed temperature up to 170 but it turned out fine anyway, of course!

Preach it! I can NEVER get to 170°F, especially at this time of year in the garage. I literally add boiling water and only get around 160-165°F due to all the low-tech water transferring i do (gallon pitchers). Since I batch sparge i don't sweat it too much though.

 

[smmcdermott]

Yes that is correct you want to get the sparge up close to 170F. Your no longer working to get the enzymes at proper temps. For the sparge the hotter temps will help dissolve the sugars and better rinse the grain. BUT do not exceed 170F. Above 170 you risk tannin extraction and that will make your beer astringent.

I am also new to all grain, but isn't this statement a little off. I mean, people who do decoction literally boil the grains which brings it above 170 (obviously), but people still do decoction. Is that right?

 

[maida7]

I am also new to all grain, but isn't this statement a little off. I mean, people who do decoction literally boil the grains which brings it above 170 (obviously), but people still do decoction. Is that right?

True but the gravity is much higher during a decoction and the pH much lower.

There are 3 main factors that contribute to tannin extraction: high temp, low gravity and high pH. You can raise the temp all you want when the gravity is high and pH low. But during the sparge the gravity drops and the pH rises so heat becomes more of a concern.

 

[smmcdermott]

haha, you jsut blew my mind, but thanks for the explanation. I am not to versed on PH yet...

 

[cactusgarrett]

It'll come, young padawan.

 

[maida7]

There is some argument, however, that a 170°F sparge isn't integral to a more efficient sparge. Kai did some work on this, and some searching can find it. But for advising someone new to the process, i'll bite my tongue at this time.

In one way or another you need to lower the viscosity of the wort so it will no longer cling to the grain. You can do with by dilution (adding sparge water) and/or heat (adding hot sparge water).

I haven't done any experiments so I'll trust Kai but from my personal experience raising the temp during the sparge helps with lautering. A mash can be very slow to run off at 1.100 gravity and 150F But magically starts flowing at 1.050 and 170F. Perhaps it's just the dilution but in my mind the heat helps loosen things up.

 

[cactusgarrett]

I get what you're saying. I didn't say i agree with him, as HE's the one with the data, and I'd be hard pressed to come up with a scientific explanation why his data looks like it does. I personally think along the lines that you do, and still use boiling water to sparge

 

[KFlan]

This is my first post on the site; I just had to chime in here.

I just completed my fourth AG batch about two weeks ago. I have been wondering why my efficiency was relatively low (70%) as I thought I was following great procedure. After doing about an hour of reading on hbt, I feel pretty dumb.

I batch-sparge and I have been sparging with 168 degree water, b/c I was misreading the direction to sparge with the GRAIN BED at 168 degrees. I thought I was supposed to have my sparge water at 168. AND, because of my paranoia about "the Evil Tannins", I have been heating my sparge water to a slightly lower temperature (by about 2 degrees Celsius) - figuring that it was close enough to 168 and that even if I lost some extraction at least I would not be wasting a whole batch to the aforementioned ET's.

As an experiment I am going to brew the exact same recipe, with everything being a constant, except for my sparge temp - which will be 185 deg F.

Will post the difference in efficiency.

 

[JuanMoore]

I also did some experiments similar to Brew Kaiser using cold tap water to sparge. Using my system (which is probably different from yours), I saw zero change in efficiency, drain speed, or anything else. The only thing it did was cause it to take longer to reach a boil since the starting temp was lower.

I have a HERMS and just use the HLT water at whatever temp it's at when I'm ready to sparge. It's usually about 10F hotter than the mash was, and doesn't change the temp of the grain bed significantly. The extra couple minutes of enzyme activity doesn't significantly effect the fermentability of the wort, and it makes for a faster, less complicated brew day.

 

[cactusgarrett]

There you go - very valuable experience. First-hand experience at that; something that doesn't appear as often as you think in the homebrew community. Thanks for sharing JuanMoore.

 

[maida7]

This is my first post on the site; I just had to chime in here.

I just completed my fourth AG batch about two weeks ago. I have been wondering why my efficiency was relatively low (70%) as I thought I was following great procedure. After doing about an hour of reading on hbt, I feel pretty dumb.

I batch-sparge and I have been sparging with 168 degree water, b/c I was misreading the direction to sparge with the GRAIN BED at 168 degrees. I thought I was supposed to have my sparge water at 168. AND, because of my paranoia about "the Evil Tannins", I have been heating my sparge water to a slightly lower temperature (by about 2 degrees Celsius) - figuring that it was close enough to 168 and that even if I lost some extraction at least I would not be wasting a whole batch to the aforementioned ET's.

As an experiment I am going to brew the exact same recipe, with everything being a constant, except for my sparge temp - which will be 185 deg F.

Will post the difference in efficiency.

70% is not low for efficiency. I doubt hotter sparge water will make a huge difference. Crush is usually the biggest factor. That and stiring to break up all the dough balls. There is nothing wrong with 70% but if you really want to chase a higher number, have a read thru Kai's website. He is the efficiency guru.http://braukaiser.com/wiki/index.php/Main_Page

 

[Justibone]

70% is pretty good.

 

[KFlan]

I wasn't too upset with the 70%, as I realize I'm using a bunch of equipment I picked up at garage sales. It's just that I got my own grain mill and I used a really fine crush, which I figured would get my efficiency up a little higher.

I think another problem could be that I didn't stir up the mash enough and maybe I did have some doughballs.

Maida - Thanks for posting the info from Kai, I'm definitely going to read through it.

 

[KFlan]

Off topic: Justibone I see the "EdWorts Apfelwein" under your post and have been contemplating doing it for a while now - Is it really all that its made up to be?

Never had an apple wine before. I think Edwort is the man - I wouldn't even think about brewing it if the recipe came from anybody but him.

 

[maida7]

I wasn't too upset with the 70%, as I realize I'm using a bunch of equipment I picked up at garage sales. It's just that I got my own grain mill and I used a really fine crush, which I figured would get my efficiency up a little higher.

I think another problem could be that I didn't stir up the mash enough and maybe I did have some doughballs.

Thanks for posting the info from Kai - I'm definitely going to read through it.

I have found this chart (from Kai's site) very helpful.

This chart represents "Extract content or gravity of the first wort based on the mash thickness. 100% mash efficiency, 80% fine grind extract and 4% moisture content of the malt were assumed for the grist"

Basically compare the first runnings of your mash to this chart. If your numbers match up then you know your getting 100% mash efficiency and any losses are attributed to the lauter. If your 90% or under on mash efficiency (compared to the chart) then you may want to change something like the crush, pH, time, etc...

I have found it very useful to isolate the efficiency to the various parts of the process. It makes trouble shooting much easier when you can see where the week point is. And it all starts with the mash.

 

[cactusgarrett]

Keep in mind, too, that this is an estimate - as it doesn't take into account the specifics of your grainbill (types of malts and their sugar contributions).

 

[KFlan]

Yeah that's a good chart. I can see wether the problem was not stirring the mash enough or having too cold sparge water, by determining wether the problem lies with the mash or the sparge.