Effects of high mashing temperature

[TomVA]

My first batch of beer was a stout, which is still fermenting. That recipe called for a strike water temperature of 163°F and a mashing temperature of 156°F. Since I had read to expect a temperature drop of 8-12°F when adding the grains, I heated my strike water to 165°F and it dropped to a perfect 156°F after stirring. I insulated the pot with towels and the water temperature after an hour of mashing was 150°F, so it averaged 153°F during the mash.

Today I started a batch of Southern English Brown Ale and also wanted to mash it at 156°F, so again I heated my strike water to 165°F, but this time the temperature only dropped to 160°F after adding the grains. I stirred it a bit to 158°F before covering, but this batch will mash a few degrees higher than planned.

Is there some maximum mash temperature that one needs to be careful of, sort of like the 170°F maximum to avoid tannins? What effect will hotter mashing have on the beer? Since I love bold brown ales I am hoping it will add a bit more body and maybe sweetness.

TomVA

 

[Steveruch]

My first batch of beer was a stout, which is still fermenting. That recipe called for a strike water temperature of 163°F and a mashing temperature of 156°F. Since I had read to expect a temperature drop of 8-12°F when adding the grains, I heated my strike water to 165°F and it dropped to a perfect 156°F after stirring. I insulated the pot with towels and the water temperature after an hour of mashing was 150°F, so it averaged 153°F during the mash.

Today I started a batch of Southern English Brown Ale and also wanted to mash it at 156°F, so again I heated my strike water to 165°F, but this time the temperature only dropped to 160°F after adding the grains. I stirred it a bit to 158°F before covering, but this batch will mash a few degrees higher than planned.

Is there some maximum mash temperature that one needs to be careful of, sort of like the 170°F maximum to avoid tannins? What effect will hotter mashing have on the beer? Since I love bold brown ales I am hoping it will add a bit more body and maybe sweetness.

TomVA

I've never seen anyone get such a small drop, I always get a much larger drop, 18-20 degrees. Is it possible that your thermometer is off.

 

[TomVA]

No the thermometer is spot on. As a scientist I checked this thermometer against two others when I bought it and in boiling water. It is perfect.

This is a small BIAB batch of beer, aiming to yield only 1.5 gallons of finished wort for fermenting, so my total water was only 2.7 gallons and the grain bill weighed (coincidently) 2.7 pounds. This is equivalent to 9.0 pounds of grains in a 5 gallon yield batch. Perhaps the small size of the batch played a role, i.e. more strike water per pound of grain since the boiling loss is the same for a large batch versus a small batch.

 

[Aristotelian]

I believe 160 is the max recommended mashing temp. Not sure what happens above that. I would have topped off with cold water or a couple of ice cubes.

 

[TomVA]

I just started a second batch (two in the day) and repeated the exact procedure above without any adjustments since I wanted to compare the two beers (exact same recipe except different total grain weights). Again I heated the water to 165°F and again it settled to exactly 160°F after stirred grain addition. I'll adjust my strike water temperature in the future for these small batches, but for now I wanted these two batches to be treated equally.

TomVA

 

[TomVA]

BTW, the temperature of the first batch above finished the mash at 150.6°F so the batch averaged 155.3°F.

TomVA

 

[Steveruch]

No the thermometer is spot on. As a scientist I checked this thermometer against two others when I bought it and in boiling water. It is perfect.

This is a small BIAB batch of beer, aiming to yield only 1.5 gallons of finished wort for fermenting, so my total water was only 2.7 gallons and the grain bill weighed (coincidently) 2.7 pounds. This is equivalent to 9.0 pounds of grains in a 5 gallon yield batch. Perhaps the small size of the batch played a role, i.e. more strike water per pound of grain since the boiling loss is the same for a large batch versus a small batch.

That makes sense, I didn't realize it was such a small batch,

 

[oakbarn]

It seems to me that your strike is too high for that small amount of grain. You did not say how much you mash tun decreases the temp or how much water you put in. We preheat our MLT and we have no MLT Drop. One way to solve the heat drop of an MLT is to add too hot of water and let it cool or just add cooling water in small increments to obtain the calculated strike. I love IOS App Brew Math for that.