Mash temp and gravity

[Chris Grubb]

My last brew, a porter, has a decent flavor, but slightly watery feel.
I mashed at 153 for 60 mins.
Starting gravity was 1.055 and final was 1.013 for an alcohol % of almost 5.7.
I know increasing mash temp will give a fuller mouth-feel, but how much would it lower alcohol %?
I like keeping around 5-5.5%, so if I mashed at 162-165, approximately how much would that lower my alcohol?

 

[RPh_Guy]

Might want to look into water chemistry. Sounds like you need more chloride.

 

[SoCal-Doug]

For porters (other than an English porter), you are on the low end at 1.055. Personally, i would stay in the 153-154 range and proportionally raise the grains to get a little higher OG. Depending on the yeast, you still will get X% attenuation, leaving a bit more body and flavor.

I'll assume your FG and post boil volume were on target. Lots of factors in play and hard to diagnose without the recipe and processes. And like rphguy said, the water profile can really make a difference. Hope this helps.

 

[Chris Grubb]

I have just gotten a water profile and am working on getting additions to the water squared away.
So I know I have seen a lot of discussion about lower mash temps= higher alcohol percentages and higher mash temps help with the full body mouth-feel, what would y’all consider to be low and high temps? Is 153 considered higher for a mash temp and what would the lower end of acceptable be?

 

[SoCal-Doug]

You'll find that typically a porter mashes at 152 to 156, giving more body, more malty, sweeter, and more mouth feel. Below 150, it "dry's" it out. Compare some typical beers... Dry beers like Asahi, Kirin, some light American lagers mash at 145 to 148. Dry, no body, not sweet. Porters, stouts, big beers go mid 150's. Something like a Sam Adams Boston Lager might mash at 153 or 154. Guinness clones are 150 to 154 depending on the recipe. As you pass the 160 mark, you risk denaturing (killing) the enzymes that do the conversion. Passing 170 you start releasing tannins from the grain (hence why we typically shoot for 168 for a mash out).

153 is not "high". 152 is considered by many as middle of the road. You can make an excellent porter at anywhere from probably 151 to 157. It all depends on the recipe.

Mash temp is NOT the only thing that drives body and alcohol. Yeast choice will also decide. Some yeasts attenuate high, some lower (attenuation = how much sugar will the yeast convert to alcohol before it poops out). Low attenuation yeasts will have more body and malty. High attenuators give more alcohol and less body. Example: WY3711 can attenuate a Saison to 1.003 and sometimes less. Saisons may start at 1.055 or higher and be left with near nothing. Even mashing them at 156, they will still be dry as a desert because the yeast eats everything. Extreme examples of course, but just trying to show the differences.

Water chemistry is a major factor. Your ratio of sulfates to chlorides drives favoring malt or hops. Your quantity of certain chemicals favors the darker or lighter beers. Beersmiths porter water calls for 300ppm chloride and 100ppm sulfate. [very] Imbalanced toward malt highlighting. While the "yellow and dry" profile is more like 100ppm sulfate and 45ppm chloride. Completely opposite of a dark heavy beer and less of both chemicals.

 

[RM-MN]

My last brew, a porter, has a decent flavor, but slightly watery feel.

My porters usually do have a watery feel....for about 2-3 months at which point they magically get more body as they mature. Give your porter time to mature instead of trying to fix a non-problem.

As you pass the 160 mark, you risk denaturing (killing) the enzymes that do the conversion. Passing 170 you start releasing tannins from the grain (hence why we typically shoot for 168 for a mash out).

Tannin extraction is driven by high pH, not temperature. If your wort pH is where it should be you can boil the grains without extracting tannins which is what is done in a decoction. When doing a fly sparge you can continue sparging until the pH raises and if you continue to sparge you get tannins.

 

[SoCal-Doug]

Tannin extraction is driven by high pH, not temperature

Gravity and temperature ALSO play a role in tannin release. But the purpose of my comments were to give the poster some ranges and ideas, with some very basics of why there may be an issue.

 

[Chris Grubb]

My porters usually do have a watery feel....for about 2-3 months at which point they magically get more body as they mature. Give your porter time to mature instead of trying to fix a non-problem.



Tannin extraction is driven by high pH, not temperature. If your wort pH is where it should be you can boil the grains without extracting tannins which is what is done in a decoction. When doing a fly sparge you can continue sparging until the pH raises and if you continue to sparge you get tannins.

If that’s the problem, I will never find out for sure...
they don’t hang around that long

 

[burntchef]

I had a similar problem to yours, until I bought more kegs! lol seriously get more storage as I am now brewing immediately after kegging to allow time to ferment 3wks and age prior to drinking.
Eric