SmokingDog
Well-Known Member
Would a high mash temp and accidently prolonged mash time produce a high FG?
Quick question: higher and prolonged mash
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beermonkey50
Member
high temp - yes at around 70-76C you will get a lot of dextrins and less fermentable sugars. This is how low alcohol beers are mashed. B amylase is active which will produce unfermenatable dextrins mostly.
Long time will help produce more fermentable extract but important to mash at lower temps eg 64C and 72C stands for max fermentable extract
Long time will help produce more fermentable extract but important to mash at lower temps eg 64C and 72C stands for max fermentable extract
Golddiggie
Well-Known Member
What temperature did you mash at?? Longer mash times shouldn't result in any change of the FG. I typically mash for 60 minutes or longer. I've done 90 minutes mashes too.
BTW, for those of us that don't think in C, post temps in F... I don't think in metric since I'm old enough that 'standard' or SAE is my standard.
BTW, for those of us that don't think in C, post temps in F... I don't think in metric since I'm old enough that 'standard' or SAE is my standard.
beermonkey50
Member
Sorry, I'm from South Africa where we went metric in 1971. deg F is foreign to me and 0to 100 makes more sense
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SmokingDog
Well-Known Member
Mashed at 159-60 for about 125 mins.
My FG isnt dropping below 1.031. OG was 1.073
My FG isnt dropping below 1.031. OG was 1.073
beermonkey50
Member
Thats too high (71C) - precisely the temp to make a low alc beer, which is why your FG is so high. You need to go to 150F (65C)
Golddiggie
Well-Known Member
That high of a mash temp is what did it... That's above the full body mash temp range (caps about 158F)... Not surprised the FG is stopping at 1.031...
BTW, is that reading from a hydrometer or refractometer?? If refractometer, is it adjusted (spreadsheet)??
Not to get into a debate about F vs. C, but C [IMO] is far less precise. If I have a thermometer that reads 152.1 it makes complete sense to me. I wouldn't even know where that would fall in the C range. I'm not about to use a converter app to turn it into something I can use. In the US, we didn't start looking at the metric system (where I went to school) for the mainstay. Everything was still in standard/SAE terms through high school (graduated in 1988) with some things also listed in metric, but that was secondary.
It's all well and good that you can use C, but since this is an US based web site, please have the courtesy to also post in F. /off topic I see that you did this already, thanks...
BTW, depending on what I'm after, I'll mash in the 150-156F range (mostly in the 150-152F range)... Last night's batch was mashed at 152 for an hour. It was my mocha porter, that I'm hoping will go to about 9%...
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SmokingDog
Well-Known Member
High Temp - kinda what I thought. English nut honey brown. Now a fairly "SWEET" version.
OPINIONS:
Should I bother spending the time to bottle, or just dump it in a keg and drink it. I think I will dry hop a little to balance some of the sweetness though. (I think I jsut answered my own question! HA.)
OPINIONS:
Should I bother spending the time to bottle, or just dump it in a keg and drink it. I think I will dry hop a little to balance some of the sweetness though. (I think I jsut answered my own question! HA.)
beermonkey50
Member
Actually should not be sweet - sweet sugars are fermentable- dextrins are much less sweet - full bodied yes but residual sweetness indicates incomplete attenuation
It seems to me that mashing at a high temperature for a long time should eventually make a very fermentable wort. Eventually the enzymes should break down all the starches and dextrins to simple (and very fermentable) sugars. It just might take a long time.
I'll just throw my thought process down in case I'm really wrong.
Our grains are made up of many long chain starches. We can think of a starch as a necklace of sugar units linked together. If we say that one sugar unit is an S then we can say that a typical starch looks like SSSSSSSSSSSSSSSSSSS.
The enzymes at low temperatures go along and cleave off a sugar from the end of the starch. The enzymes at higher temperatures randomly cleave the starch at any point along the chain.
Mashing at low temperatures SSSSS => S + SSSS => S + S + SSS => S + S + S + SS => S + S + S + S + S
We can see that mashing at a low temperature will only give us simple sugars if we mash to completion.
Mashing at high temperatures SSSSS => SS + SSS => S + SS + SS => S + S + S + SS => S + S + S + S + S
Mashing at a high temperature will quickly convert long starch molecules to dextrins. Eventually these dextrins should be converted to simple sugars.
Mashing at an intermediate temperature will give the fastest conversion to simple sugars. At these temperatures the long starch molecules are quickly cleaved randomly along the chain by the enzymes most active at high temperatures. This creates a lot of "chain ends" which are quickly attacked by the enzymes that work at low temperatures.
I don't have a ton of experience with mashing at different temperatures but it seems from the scientific side of things, you can get to a very fermentable wort anywhere between 140-160F however it might take significantly longer than any of us would expect if you are outside of the 149-155F sweet spot most of us work in.
I'll just throw my thought process down in case I'm really wrong.
Our grains are made up of many long chain starches. We can think of a starch as a necklace of sugar units linked together. If we say that one sugar unit is an S then we can say that a typical starch looks like SSSSSSSSSSSSSSSSSSS.
The enzymes at low temperatures go along and cleave off a sugar from the end of the starch. The enzymes at higher temperatures randomly cleave the starch at any point along the chain.
Mashing at low temperatures SSSSS => S + SSSS => S + S + SSS => S + S + S + SS => S + S + S + S + S
We can see that mashing at a low temperature will only give us simple sugars if we mash to completion.
Mashing at high temperatures SSSSS => SS + SSS => S + SS + SS => S + S + S + SS => S + S + S + S + S
Mashing at a high temperature will quickly convert long starch molecules to dextrins. Eventually these dextrins should be converted to simple sugars.
Mashing at an intermediate temperature will give the fastest conversion to simple sugars. At these temperatures the long starch molecules are quickly cleaved randomly along the chain by the enzymes most active at high temperatures. This creates a lot of "chain ends" which are quickly attacked by the enzymes that work at low temperatures.
I don't have a ton of experience with mashing at different temperatures but it seems from the scientific side of things, you can get to a very fermentable wort anywhere between 140-160F however it might take significantly longer than any of us would expect if you are outside of the 149-155F sweet spot most of us work in.
Right there with you man. Did my first BIAB on a ceramic stove top and did not realize the heat keeping properties of these things and mashed at a whopping 164F! I had a partial addition of DME or I might have had non-alcoholic beer. See this thread for similar discussion. I began cold crashing my bitter/brown today and will bottle (I don't keg) tomorrow or so. I just didn't want to tie my swamp cooler and bucket up any longer not really knowing what to expect. Good luck with your North Icelandic Brown
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SmokingDog
Well-Known Member
... your North Icelandic Brown
I like that, hmmm...In keeping with "The Dog's" brew naming conventions, what would be a good dog breed from that region?
previous brews...
"Leg Humpin' Pumpkin"
"War Dog IPA"
"Bad Scottie"
etc...
Note: I am going to transfer to a keg, dry hop and cold crash for 2-3 days, bottle half and then carb the rest.
FYI, it's actually alpha amylase that's primarily active at the higher temperatures.
Your example is a bit flawed. From How To Brew: 'Alpha is able to get within one glucose unit of a amylopectin branch and it leaves behind an "alpha amylase limit dextrin." '
True, you are right. My example is a little too simplified because of the issues with branching points in the starches. I still don't see any reason why you won't be able to obtain a highly fermentable wort using only alpha amylase. I would agree that it might take a very long time but it seems like it should still work.
I think the real issue is that you might be denaturing the amylase enzymes slowly at normal mash temperatures. Using the figures here it looks like most of your enzymes denature after around 30 minutes to 90 minutes at normal mash temperatures with higher mash temperatures denaturing faster. Thus, there really isn't much of a reason to mash for a long time at normal mash temperatures because all the enzymes are destroyed so this doesn't really help too much to create highly fermentable wort.
I guess what I've learned from taking a little closer look at all of this is that we probably get highly fermentable wort by mashing at low temperatures mainly because it prevents denaturation of the amylase enzymes. Obviously we want to have the highest rate we want to work at the highest temperature we can without degrading the enzymes (low 150s F).
It would be interesting to try holding the mash temp at around 158F for 15 minutes to denature all of the beta amylase and then drop the mash temp down to 145 F and see if you could get a fermentable wort from just using active alpha amylase enzymes. I'm not sure this would be any better than what we normally do but it would just be interesting to see if it worked.
I think the real issue is that you might be denaturing the amylase enzymes slowly at normal mash temperatures. Using the figures here it looks like most of your enzymes denature after around 30 minutes to 90 minutes at normal mash temperatures with higher mash temperatures denaturing faster. Thus, there really isn't much of a reason to mash for a long time at normal mash temperatures because all the enzymes are destroyed so this doesn't really help too much to create highly fermentable wort.
I guess what I've learned from taking a little closer look at all of this is that we probably get highly fermentable wort by mashing at low temperatures mainly because it prevents denaturation of the amylase enzymes. Obviously we want to have the highest rate we want to work at the highest temperature we can without degrading the enzymes (low 150s F).
It would be interesting to try holding the mash temp at around 158F for 15 minutes to denature all of the beta amylase and then drop the mash temp down to 145 F and see if you could get a fermentable wort from just using active alpha amylase enzymes. I'm not sure this would be any better than what we normally do but it would just be interesting to see if it worked.
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