Mash Temp Problem

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Rockweezy

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So I finally got around to testing and calibrating my thermometer on my mash keggle and realized it was like 10 degrees off. Thus, every mash as been at 142 instead of 152. The only beer I have been happy with since AG brewing has been an oatmeal stout. How does that mash temp mishap affect my final product?
 

JesseRC

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I am a bit confused about mash temp effects as well. I have heard that lower mash temps will make a more fermentable wort, and higher temps (closer to 160) will make a less fermentable wort. Less fermentable meaning it wont finish out as much in terms of gravity. However does mash temp affect the the ability to hit OG. Can you it you OG spot on with a high mash temp and then it just doesnt finish out to target FG?
 

Yooper

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I am a bit confused about mash temp effects as well. I have heard that lower mash temps will make a more fermentable wort, and higher temps (closer to 160) will make a less fermentable wort. Less fermentable meaning it wont finish out as much in terms of gravity. However does mash temp affect the the ability to hit OG. Can you it you OG spot on with a high mash temp and then it just doesnt finish out to target FG?
Sure. You can have full conversion at 147 degrees or at 158 degrees. You'll hit the OG, and the wort will look the same. The difference is the composition of the sugars, though. The 147 degree mash may finish as low as 1.007 (it's happened to me!) while the 158 degree mash may not get below 1.018, for example. Of course, ingredients like the malt bill and the yeast also play a part. But generally speaking, the higher the temperature in the mash, the more "dextrinous" and heavy it ends up.
 

JesseRC

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Thanks Yooper, that's not always covered in "mash temp" threads. That's good to know, i suspected that was the case. You see alot of threads about not hitting target OG, and the thread gets into the temp of mash, but I suspect its more about volume of wort collected, the time of the mash, and sparge temp, and how well sugars are rinsed off the grain. The point I'm getting at, just becasuse you hit target OG, that doesnt mean you'll hit target FG.

So, back to OP, his beers were probably a bit on the dry side right.
 
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I missed my mash temp of 155 today and got 149. I could mess around and heat sparge water to boiling but that would take time and I'm just going to worry about it. I'll still get conversion.

How exactly will this effect my beer? I'm thinking a dry thinner beer would work ok for a summer time wit.
 
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