Difference between HIGH mash + dextrose vs LOW mash

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beervoid

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If I brew the same beer with same ABV and FG.
But I mash one very high and then add some dextrose to bring it down to the same FG and ABV vs just mashing lower.
Would there be a difference cause of the higher amounts of dextrins or would this be obsolete as the beer is dried out by use of dextrose?
 

John Eberly

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You will end up with a “thicker beer with more mouthfeel. High mash temp creates unfermentable dextrins which remain after fermentation. Adding dextrose will not reduce these, just increase the abv.
 
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beervoid

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You will end up with a “thicker beer with more mouthfeel. High mash temp creates unfermentable dextrins which remain after fermentation. Adding dextrose will not reduce these, just increase the abv.
Yes but to keep the same fg and abv one would have to lower the total malts as well
 

stickyfinger

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Here is an extreme example - you have to reduce the malt considerably in the high mash beer to get the same FG as the lower mash beer. The high mash beer would taste much thinner:

mash at 165F, OG 1.022, FG 1.008 for 65% AA, 1.8% ABV, then add sugar to get up to 5.5% ABV

mash at 150F, OG 1.050, FG 1.008 for 85% AA, 5.5% ABV
 

stickyfinger

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I think a more interesting question would be if you could tell the difference between these two beers:

mash at 165F, OG 1.050, FG 1.018 for 65% AA, 4.2% ABV, then add sugar to get up to 5.5% ABV

mash at 150F, OG 1.050, FG 1.008 for 85% AA, 5.5% ABV
 

Vale71

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You can't have the same ABV and the same FG but a different amount of dextrins, it's simply not physically possible.
If you have the same amount of alcohol per unit of volume the alcohol induced error will be the same, if you then have the same FG and both beers are fully fermented then that means you have the same amount of unfermentable sugars leading to the same measured density. If you had more dextrins the the FG would have to be higher, it's just not possible otherwise.
 

Smellyglove

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You can't have the same ABV and the same FG but a different amount of dextrins, it's simply not physically possible.
If you have the same amount of alcohol per unit of volume the alcohol induced error will be the same, if you then have the same FG and both beers are fully fermented then that means you have the same amount of unfermentable sugars leading to the same measured density. If you had more dextrins the the FG would have to be higher, it's just not possible otherwise.
I suck at logical thinking, so I'm not saying against you, but here's what I've done several times:

Brew a beer, ferment it etc and drink it.

Then to double the batch size I've brewed a High Gravity version of it, and watered it down 50% before fermentation. Same OG and after a few try and fails.. same FG.

So same OG and same FG. The watered down version tastes nothing like the non watered down version. The watered down version is WAY more drier on the tongue. Even after upping salts etc.

I must believe that there's a different amount of dextrins, as I have to mash 4C higher to get the same FG in the diluted version.
 

stickyfinger

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Are you saying that there is a big difference between a low gravity version of your beer and a diluted high gravity version of your beer? If so, have you done it side by side?

I think the types of dextrins might be different between a high mash and low mash beer for a constant FG, but it is probably not known what impact the dextrin composition has on the flavor, if any. It seems the Englishy yeasts often leave a higher FG. I have been wondering if that is maybe due to leaving behind 3- or 4-unit sugars when more attenuative yeasts eat them up as well. Not sure.

I suck at logical thinking, so I'm not saying against you, but here's what I've done several times:

Brew a beer, ferment it etc and drink it.

Then to double the batch size I've brewed a High Gravity version of it, and watered it down 50% before fermentation. Same OG and after a few try and fails.. same FG.

So same OG and same FG. The watered down version tastes nothing like the non watered down version. The watered down version is WAY more drier on the tongue. Even after upping salts etc.

I must believe that there's a different amount of dextrins, as I have to mash 4C higher to get the same FG in the diluted version.
 

Vale71

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I suck at logical thinking, so I'm not saying against you, but here's what I've done several times:

Brew a beer, ferment it etc and drink it.

Then to double the batch size I've brewed a High Gravity version of it, and watered it down 50% before fermentation. Same OG and after a few try and fails.. same FG.

So same OG and same FG. The watered down version tastes nothing like the non watered down version. The watered down version is WAY more drier on the tongue. Even after upping salts etc.

I must believe that there's a different amount of dextrins, as I have to mash 4C higher to get the same FG in the diluted version.
Your situation is somewhat different but let's try and dig deeper. If you have the same ABV you'll have the same mix of water and alcohol giving you your base density, which will be lower than 1 as alcohol is lighter than water. What gives you the actual FG is this base density + X amount of residual extract per unit of volume. So basically for your two beers:

FG1 = Base_density1 + Extract_density1
FG2 = Base_density2 + Extract_density2

But we know that FG1 = FG2 so let's call both FG and we have:

FG = Base_density1 + Extract_density1
FG = Base_density2 + Extract_density2

But we also know that Base_density1 = Base_density2 because both beers have the same ABV so let's call that Base_density and we have

FG = Base_density + Extract_density1
FG = Base_density + Extract_density2

We can strike out Base_density without changing the truth value of the equation and then we have

FG = Extract_density1
FG = Extract_density2

Both terms on the left being equal it follows

Extract_density1 = Extract_density2

Q.E.D. ;)
 

CascadesBrewer

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This is a topic I am interested in.

A somebody that has struggled to get solid mouthfeel in beers, based on my experience and reading I am fairly confident that the standard "low mash temp = thin/dry beer; high mash temp = thick/sweet beer" is false, or at least not that clear cut. If you like Brulosophy, they have a few experiments on this topic.

The thing that most people overlook is that alcohol adds sweetness and body to a beer. In the case of mash temps, the higher alcohol of the lower mash temp beer mostly cancels out the dextrins of the higher mashed beer. I plan on doing a few experiments on this myself to prove this to myself.

I actually have a split batch in kegs right now that was related to this topic. I split a 5 gal batch of Porter at fermentation time and added 10% table sugar ito half. My goal was to test a 5% beer vs a 6% beer. Unfortunately, I realized as the beer was coming to a boil that my thermometer was about 10F off and I actually mashed around 162F. So I have a 3% beer vs a 4% beer. I plan to get some input from my beer club on these, but I can pick out the 3% beer and it is thin and too roasty (not thick and sweet) and the 4% beer has better mouthfeel and balance. The OG on these beers was 1.052 and 1.060 with a FG around 1.030 (so actually 2.9% vs 3.9%).
 

stickyfinger

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This is a topic I am interested in.

A somebody that has struggled to get solid mouthfeel in beers, based on my experience and reading I am fairly confident that the standard "low mash temp = thin/dry beer; high mash temp = thick/sweet beer" is false, or at least not that clear cut. If you like Brulosophy, they have a few experiments on this topic.

The thing that most people overlook is that alcohol adds sweetness and body to a beer. In the case of mash temps, the higher alcohol of the lower mash temp beer mostly cancels out the dextrins of the higher mashed beer. I plan on doing a few experiments on this myself to prove this to myself.

I actually have a split batch in kegs right now that was related to this topic. I split a 5 gal batch of Porter at fermentation time and added 10% table sugar ito half. My goal was to test a 5% beer vs a 6% beer. Unfortunately, I realized as the beer was coming to a boil that my thermometer was about 10F off and I actually mashed around 162F. So I have a 3% beer vs a 4% beer. I plan to get some input from my beer club on these, but I can pick out the 3% beer and it is thin and too roasty (not thick and sweet) and the 4% beer has better mouthfeel and balance. The OG on these beers was 1.052 and 1.060 with a FG around 1.030 (so actually 2.9% vs 3.9%).
interesting.
 
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You can't have the same ABV and the same FG but a different amount of dextrins, it's simply not physically possible.
If you have the same amount of alcohol per unit of volume the alcohol induced error will be the same, if you then have the same FG and both beers are fully fermented then that means you have the same amount of unfermentable sugars leading to the same measured density. If you had more dextrins the the FG would have to be higher, it's just not possible otherwise.
I had to lower the base malt in the high mash beer and replace it with dextrose.
Og will be different but abv and fg will be the same.

So you are saying that lowering the amount of base malt of the high mash beer will lower the dextrins to that of the level of the low mash beer.

By this logic I would suspect the high mash beer to taste thinner just based purely on the lower amount of malts going in.
 

Vale71

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Og will be different but abv and fg will be the same.
Which is also physically impossible. If you have the same amount of alcohol in your finished beer this must mean that yeast processed the same amount of fermentable sugars. So if FG and ABV are the same OG must be the same too, as OG = FG + fermentables - alcohol_error.
 
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beervoid

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Which is also physically impossible. If you have the same amount of alcohol in your finished beer this must mean that yeast processed the same amount of fermentable sugars. So if FG and ABV are the same OG must be the same too, as OG = FG + fermentables - alcohol_error.
Sorry, I meant OG without the dextrose added. Less malts.
 
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CascadesBrewer

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I had to lower the base malt in the high mash beer and replace it with dextrose.
Og will be different but abv and fg will be the same.

So you are saying that lowering the amount of base malt of the high mash beer will lower the dextrins to that of the level of the low mash beer.

By this logic I would suspect the high mash beer to taste thinner just based purely on the lower amount of malts going in.
I am curious how this turns out. Report back after it is conditioned. If I were a betting man, I would put my money on "cannot tell the difference." I would think that the extra fermentability of the dextrose will cancel out the less fermentable wort due to high mash temp.
 

Smellyglove

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Are you saying that there is a big difference between a low gravity version of your beer and a diluted high gravity version of your beer? If so, have you done it side by side?

I think the types of dextrins might be different between a high mash and low mash beer for a constant FG, but it is probably not known what impact the dextrin composition has on the flavor, if any. It seems the Englishy yeasts often leave a higher FG. I have been wondering if that is maybe due to leaving behind 3- or 4-unit sugars when more attenuative yeasts eat them up as well. Not sure.
Well the OG is the same into fermenter, but I boil a higher gravity wort, then dilute it into the fermenter. No side by side is needed. The difference is striking. It's a beer I've brewed several times (about 8 times in "normal version), and about a handful of times in the high gravity version.
 

Vale71

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Sorry, I meant OG without the dextrose added. Less malts.
I think you're getting hung up on OG and FG and dextrins and missing the larger picture. You can replace some malt with simple sugars and then mash higher to get to the same ABV and FG but the beer will still be different because if you take malt out you also take out the proteins this would bring into the wort and replacing it with 100% protein-free carbohydrates.
 
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beervoid

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I think you're getting hung up on OG and FG and dextrins and missing the larger picture. You can replace some malt with simple sugars and then mash higher to get to the same ABV and FG but the beer will still be different because if you take malt out you also take out the proteins this would bring into the wort and replacing it with 100% protein-free carbohydrates.
Right, less malts is less proteins, less beta glucans etc.
Mashing higher gives more dextrins but I doubt it would make up for the other stuff missing.
Cheers
 
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