Best way to fix missed mash temp.

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treesmcgee

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I've been noticing lately the efficiency of my saccharification rest has been going down, with noticeable drops in starting gravity, even after boil. I had been checking the temp of the mash, and checked it, for instance right at the end of my 60 minute mash, (11 lbs 2-row, and a couple lbs of specialty grains), and saw the temp of the mash at around 148-149, 6 or so degrees below my target mash temp. I suppose I don't know when exactly, or how fast the temperature dropped below target mash (I single infuse, with a Gott cooler, and batch sparge, infusion temp: 170.5 for a 68 degree grain bed, adjusted for equipment temp, no pre-heating) temperature, but I am supposing this is the culprit in the drop in my efficiency (For instance, with that same recipe, I was getting 1.058-1.060 starting gravities, now I'm getting 1.051ish). If this is indeed the issue, is my solution (for the time being, as it is so cold around these parts) an increase in strike water temp equivalent to the missed temperature? Or?

Cheers boys and girls!:mug:
 
If you preheat the cooler, you won't drop more than 1 degree in an hour or 75 minutes.

I can't imagine that would affect efficiency though, unless you're not getting complete conversion.
 
Best way to preheat a cooler? Throw in some hot water?

Isn't a cooler mash not going to get full conversion out of the grain? Say for instance if I missed completely and had a mash at 148 the entire time? And if that isn't the case, and I have not varied from my recipe, what is the most common culprit of a lack of conversion? Grain? Grind? (I grind pretty well) Sparge? (I batch sparge in two or three separate stages with proper temp and pH)
 
Best way to preheat a cooler? Throw in some hot water?

Isn't a cooler mash not going to get full conversion out of the grain? Say for instance if I missed completely and had a mash at 148 the entire time? And if that isn't the case, and I have not varied from my recipe, what is the most common culprit of a lack of conversion? Grain? Grind? (I grind pretty well) Sparge? (I batch sparge in two or three separate stages with proper temp and pH)

Yes, near boiling water (but not too hot- it'll warp the cooler) for 15 minutes, then drain. I used to do it with my strike water- just add my strike water at 180 and let it cool to strike temps, but when it's cold, it actually drops to below strike temps!

You'll get full conversion at 148, but it might take longer. Usually, mashing at 154ish means the mash is often converted in 30-40 minutes, though. I've mashed at 156 and checked for conversion in 20 minutes and had full conversion! Cooler temps take longer, of course, but unless the mash was at 149 or less the whole time, 60 minutes is almost always sufficienct.

I'm thinking that something else is going on. Different crush? Different water chemistry?
 
When I bought my cooler setup the sales guy said he sees a drop of 15 degrees with the coolers. I shoot for 15 degrees above mash temp and have be hitting the numbers I need.

www.brewheads.com has a calculator that'll tell you how much water and at what temp to add to raise your mash temp.
 
Do you happen to use a braid as a filter? I ask as when I did I got consistent efficiency for my first few batches, then my percentages got erratic. I don't know if it was channeling or the braid floating up or getting stretched or what it was. Switched to a copper manifold and I have been consistent, with improved efficiency ever since.
 
When I did 5 gallon batches, my strike temp would drop 13 degrees. With 10 gallon batches it drops 18 degrees. Give or take.

I pre-heat.
 
I crush pretty finely, a 1.5 on the Barley Crusher at my LHBS. I do all the crushing myself, so no LHBS issue there. My water chemistry has been the same, I started using my local tap water and had the first few awesome, and the next few not so much, so it can't be a change in water chemistry. I'm thinking it has to deal with the mash temp or possibly my sparge?
 
Possibly missing your temperature on your batch sparge. If you don't get the grainbed up to 170 or so, the sugars won't be as viscous and not as easily washed from the grains.........just a thought.
 
I mash at 149 all the time and get full conversion. Anything above, what 147-165 ish range should get you full conversion, its more about ensuring you have consistent mash crush, and no doughballs for the most part. Otherwise, maybe just wait a bit longer to ensure you're complete or do a ph test?
 
Possibly missing your temperature on your batch sparge. If you don't get the grainbed up to 170 or so, the sugars won't be as viscous and not as easily washed from the grains.........just a thought.

I almost never seem to be able to get my sparge water above about 150, and still get great efficiency. There are some threads here that have confirmed people do sparges at say 140-150, saying htey have no adverse effects from doing so. So long as you put more water in, it rinses the released sugars off the grains. Also, the lions share of the sugar comes from the first runnings anyway, and you're just getting a bit more from the second runnings.
 
I did my first partial mash yesterday, water was around 163 or so when I dropped the grain bag in. I put the lid on, wrapped it with a large heavy blanket, checked on it 10 mins later and it was about 148 or less.

This was being done in a 20qt pot on the stove. Lots of head space in this pot I noticed.

How can I get the mash to stay in the 150 - 155 range??

30 mins later it was down around 130 so I added some preboiled water.
 
Yooper said:
I've mashed at 156 and checked for conversion in 20 minutes and had full conversion! Cooler temps take longer, of course, but unless the mash was at 149 or less the whole time, 60 minutes is almost always sufficienct.

How are you checking efficiency right after mash? Hydrometer reading out of the mash? Refractometer? Sorry but I have just done a few AG batches and have struggled with getting a decent gravity reading. I usually check right before I boil but at that point it is too late to add mash time if my conversion was weak. Thanks.
 
How are you checking efficiency right after mash?
She's checking for 'conversion' not 'efficiency.' A bit of a difference. Check for conversion with iodine. Go here and read down to Testing Your Conversion: http://www.realbeer.com/jjpalmer/ch14.html

Checking for efficiency at this stage is best done with a refractometer, IMO. I don't check until everything is in the brew kettle and before the boil gets going. I compare this reading to the estimated pre-boil gravity number in beersmith, just to confirm I'm on track.

In your case, where your conversion was weak, maybe you could add a bit of DME to bring your est. pre-boil gravity number up to your target. Another option might be to boil off enough water until your number comes up to your target and then start your 60 minute boil clock (or 90 minute or whatever). Your batch size will be smaller than you originally planned and you may or may not want to adjust the amount of your hop additions.
 
I did my first partial mash yesterday, water was around 163 or so when I dropped the grain bag in. I put the lid on, wrapped it with a large heavy blanket, checked on it 10 mins later and it was about 148 or less.

This was being done in a 20qt pot on the stove. Lots of head space in this pot I noticed.

How can I get the mash to stay in the 150 - 155 range??

30 mins later it was down around 130 so I added some preboiled water.

so any pointers on keeping the water in the proper range?? See above for whats taking place and my precautions to keep it in the proper range.
 
If my mash temp is too low, I bring it up by stirring the mash with a heat stick for a few minutes until I get it to where I want it. I guess that is the equivalent of direct firing a metal mash tun?
 
Without using a cooler, you'll probably want to check the temp every 20 minutes and when it's 5F low, turn the flame on low and stir until you get back to your target.

If you're direct heating, that's probably the best way. But as Bobby said, stir because you don't want one area to be 175, while the rest is 140! Stir well as you heat.

You can also have a bit of boiling water on hand, and a couple of ice cubes. If you stir well, and you're just a little low, a little boiling water will fix you right up. If you miss high, one or two ice cubes might be all you need.

Insulate your MLT, and of course preheat it before using if it's not direct fired, and it should hold temperatures well once you get the right temperature.
 
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