High mash temp - what to expect?

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freisste

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I brewed my first partial mash and I must say that overall it went better than I thought. It took longer than expected, but wasn't too difficult (beginner's luck, I suppose).

The one issue is that I used an app on my phone to determine a strike temp for my mash in. It told me to heat the water to 162f to end up at 154f after adding grains. I did so and when I took a temp reading after adding the grains, it was at 158. I put the pot in the oven which I had set to 170 and shut off 10 minutes prior. After an hour it was 154. How bad is this? Not worried about style so much as taste. I'm keeping this general so the discussion can help everyone learn, but if my recipe is important I can share.
Thanks, everybody.
 

JonM

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If you had too high of a mash temp, you might end up with a sweeter than expected beer (high FG). But it'll still be beer.

Did you check the temp as you were mashing? Lots of us add the grain, wait five minutes, then check temp and add hot/cold water as needed to get te temp dialed in.
 
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freisste

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I was kind of in a hurry because I had already wasted more time than I expected that morning, so I didn't wait to take more temp readings or check at all during the mash.

Some more information:
1. I don't actually care (too much) about the mash temp. I was really just taking a stab and hoping to hit it. I was surprised to be off by 4-5 degrees.
2. I only chose my target of 153f because I heard that you want to mash between 148-158. That may not even be true, but I shot for the middle.
3. I hit my expected OG on the head (1.067). Am I right in assuming I converted the correct amount of sugar, but I will have a larger proportion of unfermentable sugar (expect a high FG)? Or is it just a coincidence because I only has 3lbs of grain (some of which was crystal) compared to 6lbs DME?
Thanks again.
 
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freisste

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Also, is it critical that the mash cools through a range of temperatures so it sees time at the top of the mash temp as well as lower temps? Or would holding at a single temperature be ideal? Or am I over-thinking this and trying to have an Anheuser-Busch level of control over a microbrew with about $150 worth of equipment (vs their multi-million dollar mashing operations)?
 

frazier

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With my mash cooler, the temp only drops a degree or two over the course of an hour. Your equipment may differ.

There are several factors that can cause a high FG, and mash temp is one of them. But since yours is only a partial mash, and the temp wasn't too terribly high, I doubt you'll see much of a problem. Just aerate well and pitch a big starter, you'll be fine.

My one stuck fermentation, in an early all-grain batch, was a stout that finished at 1.032. I traced the problem to a bogus digital thermometer that read 8 to 10 degrees low - so I mashed in the low 160's. It was still beer, people liked it.

No worries!
 
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freisste

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I suppose I will RDWHAHB. I figured I was worrying too much and didn't think I did too badly, I guess I was just wondering for next time when I make bigger mistakes...

Thanks.
 
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