Best Solution for mashing in the cold

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Gameface

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I'm making my first batch this winter. I let my backyard brewing area freeze over and I've been to lazy to dig it out and break up all the ice until now. We're having a wonderfully balmy Feb. day at 40F, so I decided to go for it.

So I was wondering, if I knew that my mash temp would drop more than normal what would be the best way to deal with it?

1) Mash in at a higher temp so that at the end of the 60min mash I was at my desired mash temp.

2) Mash in at the normal temp and stop the mash early before it dropped below the desired mash temp (assuming I had full conversion).

3) Monitor the temp and maintain the correct temp by adding hot water during the mash.

4) Start the mash a little high and let it drop below the desired mash temp so that I get a full 60 min mash.

This is somewhat hypothetical. My solution was to mash in a little hot and let it go the full 60 min. Just wondering about some mash theory type stuff. For one, if you convert grain at a high mash temp, say 156, then the mash temp falls and the mash ends at 148 will the fementability of the wort be more like a consistent 156 mash or a 148 mash? Or will it be like a 152 mash? Basically what I'm asking is if you convert the grain at 156 is the sugar locked in at that point or will dropping the mash temp make it more fermentable?

My details, although this question is more about the general concepts involved.

18.5lbs grain.
Mash in with 6g water at 165F.
Target mash temp 152F.
Sparge with 10g at 170F

I'm making a Scottish 80/-
 
what type of mash tun are you using? I use a picnic type cooler and wrapped it in duct insulation and had no problem holding temps in 7deg weather
 
I use a 10g Rubbermaid cooler. Again, this isn't really about fixing anything for me, I'm curious about the concepts involved.

If you start a mash at 156 and the majority of the starch converts at 156 but the mash temp falls to 148 for the last 30 min will the wort be fermentable like it was mashed at a consistent 156 or like a 152 mash or like a 148 mash?

Just curious about how this works. I'm a RDWHAHB type guy and my mash is doing what it's going to do for this brew day. I'm sure I'll end up with beer one way or another.
 
Ive done overnight mashing and had some pretty dramatic temp drops in my 5 gal igloo , imho (not proven science) my beers have come out pretty much like i did a 60 min mash some say you end up with a thinner beer but in my exp i couldnt tell.You could wrap a blanket or sleeping bag around your tun to try and help with the loss!
 
I started mashing inside. It only takes about 2.5-3 gallons to mash at 1 qt/gallon, so I can easily do that on a stovetop. I let the mash tun sit in the kitchen while I set up the rest of the gear outside. That way, the outdoor temps don't affect things too much.

Of course, it is a heckuva lot colder here (0 degrees F at the start of today's brew - my starsan spray bottle and all my quick releases froze)
 
Yeah. I let my igloo set outside (well, in the garage) during the mash and it started at 156 and ended at 148. Ita about 15 degrees outside. Should have kept it inside I guess. I dont worry about it too much. It will be beer.
 
I keep my grain and mash tun inside until I'm ready to mash so they stay warm, I add slightly warmer strike water to the tun to pre heat and then dough in

My tun loses only 1 degree per hour and I brew in the garage, works pretty well
 
I ended up having less than 1F loss and I started high 156.5. I also didn't lose as much volume as normal. Started with 13.5g and ended with 11.5 when I planned on 10.5. But even with all that I also ended up with an O.G. of 1.052 when I had an estimated O.G. of 1.047.

LOL, can you tell I haven't brewed in a while? This brew day takes the record as my personal best in being all over the place.

I think on the balance this is going to be just fine. My IBUs were on the high side going in, 29IBUs for a Scottish 80/-, so the higher O.G. shouldn't hurt that too much. And with the higher O.G. I might get pretty close to my expected ABV even though I mashed high.

Based on the hydrometer sample I'm in for a pretty good beer. I'm using Wyeast 1728 Scottish Ale yeast and fermenting at 53F for 3 days followed by 2 weeks at 56F with a 3 day cold crash at 33F. It'll be a little late for my birthday but I'll be back in the homebrew soon after over a month without. Ahhh...
 
Ive done overnight mashing and had some pretty dramatic temp drops in my 5 gal igloo , imho (not proven science) my beers have come out pretty much like i did a 60 min mash some say you end up with a thinner beer but in my exp i couldnt tell.You could wrap a blanket or sleeping bag around your tun to try and help with the loss!

So from this I'm going to assume that the beer temp at the time of conversion determines the characteristics it will have in the wort. So if I mash the grain at 152 but the temp when I drain into the boil kettle is 148 I'm gonna have wort that performs like it was mashed at 152.
 
I've heard of others having good results by putting the mash tun on a piece of styrofoam and then putting an old sleeping bag over the whole thing.
 
I'm using Wyeast 1728 Scottish Ale yeast and fermenting at 53F for 3 days followed by 2 weeks at 56F with a 3 day cold crash at 33F.

In coming side track:off:, but have you had luck using 1728 that low before? I've used slurry from a local microbrewery that uses 1728 as their house ale yeast and not gotten any activity until I pushed my temps over 63-64. I felt these temps gave me a very strong yeast character I didn't quite care for nor have I experienced with with my goto WLP004. Then again I've never had trouble starting the irish at 62 and holding it there for 80% of the ferment.

I don't want to to totally derail the topic, but let us know how that wort ferments out would ya?
 
In coming side track:off:, but have you had luck using 1728 that low before? I've used slurry from a local microbrewery that uses 1728 as their house ale yeast and not gotten any activity until I pushed my temps over 63-64. I felt these temps gave me a very strong yeast character I didn't quite care for nor have I experienced with with my goto WLP004. Then again I've never had trouble starting the irish at 62 and holding it there for 80% of the ferment.

I don't want to to totally derail the topic, but let us know how that wort ferments out would ya?

I've used it once before with good results. However, this morning I checked the fermenter and there's no activity. I pitched at 50F and overnight it got up to 52F. I may need to let it get a little higher to get going.
 
I keep my cooler inside since it's cold.. i figure it will give me more control over my temps.

Can't wait til warmer weather so i can just do it all outside. Cleaning my gear in the cold is a PITA. Hands down my least favorite part of brewing.
 
I haven’t really ran into that problem. I might mash in maybe 1 or 2 degrees higher to compensate, but I usually don’t lose that much heat even in the cold. The trick is to preheat your mashtun with very hot water. and keep your grains inside and warm until you dough in. Also, wrap your tun with a bunch of blankets.

Think on the bright side, your chill time will be really fast!
 
I haven’t really ran into that problem. I might mash in maybe 1 or 2 degrees higher to compensate, but I usually don’t lose that much heat even in the cold. The trick is to preheat your mashtun with very hot water. and keep your grains inside and warm until you dough in. Also, wrap your tun with a bunch of blankets.

Think on the bright side, your chill time will be really fast!

I haven't ran into the problem either. I was just wondering if once the starch is converted it can increase (or decrease) its fermentability from where it was at at the moment it was converted. Since people do overnight mashes obviously it won't change simply by lowering the temp, but I still wonder if there is a certain "set" time after which the fermentability is locked in or if the temp the starch converts at is the only factor in determining its fermentability.
 
as far as I know, most of the conversion happens pretty quickly, so your mash character is going to be determined by your mash in temp (unless temp drops really fast). otherwise, the overnight mash guys would all end up with incredibly thin and dry beer, and that just doesn't seem to be the case. (never done it myself, but I feel like there would be a flurry of "my overnight mash beer finished really low!" threads and then people would stop doing it if there was a problem.)

I could be very wrong, though.
 
From what I've read, conversion happens within a half an hour, and we do a one hour mash as insurance and to make sure we get full conversion and maximum efficiency. Also, I've been told that overnight mashing is possible and some home brewers do it, but its not optimal because you would lose temp, and the extended mash time would extract astringent tannins from the grain.
 
Easy!
Go Electric!

A good cooler won't drop more than a degree or two during the mash if it's out of the wind.

Better yet, unplug your dryer and go electric!
 
Easy!
Go Electric!

A good cooler won't drop more than a degree or two during the mash if it's out of the wind.

Better yet, unplug your dryer and go electric!

I've been thinking about going electric. It's definitively on my list of possibilities.
 
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