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Mash Temp too low!!! Help!

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HoppyDaze

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So I was supposed to heat water to 164 then add my gains....then mash for 90 minutes at 152. Well I started at 164 but the temp dropped to 148 after I added the grains...can I put some more hotter water in the tun to get the temp up the four degrees? any other options?

thanks!
 
Sure, just add some hot water and stir thoroughly. I usually keep some near boiling and some ice cold water handy just in case I am off by a degree or two when I dough in.
 
Yeah, if I'm low enough to be concerned about it I bring a tea-kettle to a boil and pour it in. Beersmith has an adjust-mash tool that comes in handy for this. You enter the current temp, water volume, grain weight, and target temp and it tells you how much boiling water to add. (or however much water at your choice of temp)
 
I added water and got it up to 153 but its back down to 148...is that too low? Should I keep adding water? If so, will that have an affect on the beer??

thanks!
 
I added water and got it up to 153 but its back down to 148...is that too low?

You added hot water and got the entire mash up to 153 and it went down to 148... again? That's some serious temp loss, what are you using for a mash tun?

I would follow the advice above. Run some of the current wort off and stick it on your stove to get it all nice and hot. Add it back to the mash so your overall volume stays the same.

148 is a little low, but you'll be fine. The beer will be dry, but it will still be beer. Not to beat a dead horse, but RDWHAHB!:mug:
 
I added water and got it up to 153 but its back down to 148...is that too low? Should I keep adding water? If so, will that have an affect on the beer??

thanks!

What kind of mash tun do you use? Did you pre-heat it? Usually the temperature stays pretty stable once it equilibrates with the grains and the mash tun walls.

I'd boost the temp back up to where it's supposed to be and try to keep it there.
 
Yeah, whatever your tun is, you didn't account for the initial heat absorption. You should put the water in about 10F hotter and close the lid to wait for the (assuming) cooler to take all the heat it wants. Then stir it with the lid open until you reach your 164 strike temp, then dough in.
 
I did a 1gal batch today on the stove.. i had some crazy heat loss going on.. and also some crazy evap also...

I finally had to heat it about 4 deg. above my mash temp.. wrap the pot i was using in a towel, and hope for the best.. couldnt risk opening it anymore than i had to because the heat was being sucked out so fast..
 
+1 to all of the above....

Do you pre-heat the tun? (1gal @180-190 deg. while I heat my strike)

Where are you storing your grains? Are they cold? Let them acclimate before mashing in.

Is the top of your tun insulated? (great stuff it or place a heavy towel on top)
 
And stir, stir, stir.... it will help even the temp if the sides are cold. (I mean for the ten minutes until the temp stabilizes...)
 
great advice everyone...Im pretty sure my problem was not pre heating the tun. Also, it was only a partial mash so there was quite a bit of head space in there as well. Next time I will try taking some of the runnings and heating that to get the temp back up. Hopefully I will not have to deal with it again.

thanks again!
 
Well since it was partial mash I think you really don't have to worry about being a few degrees off. The sugar from the grains might be more fermentable but much of your fermentables are coming from the extract, so the overall beer won't be changed that much.
 
You need to make sure that you don't exceed 1.5 quarts per pound. The enzymes need to be dense enough for conversion. I would like to see what you are using that you are losing heat so fast. I use a 10 gallon cooler and I don't lose a degree after an hour. I preheat the tun with a gallon of boiling water.

If you don't have a cooler, I would get one. I picked up all of this for $100.
IMG_08521.JPG
 
Well guys, Mash temperature seems to be my biggest concern. The temperature and mash conversion are very important. I use round beverage coolers (usually the 5 gal) and without preheating them I heat my mash water about 12 degrees higher than where I want it to rest. Then after stirring it up, I cap it off and set it in the sun if I'm brewing during the day. The sun helps heat the cooler to keep it at my desired temperature. A problem I have had often is the readings I get with my thermometers. I normally use a floating thermometer and a S. S. probe thermometer and sometimes I get different readings from them, I don't know what this is, but whenever this happens I just split the difference.
 
So I was supposed to heat water to 164 then add my gains....then mash for 90 minutes at 152. Well I started at 164 but the temp dropped to 148 after I added the grains...can I put some more hotter water in the tun to get the temp up the four degrees? any other options?

thanks!
One thing I know will help - take careful notes! If this is a beer you like and will brew again (I have several faves I brew regularly), then you will get your method down. Next time use slightly hotter water (again, write this down!), and see how that works. You will find that in future batches it will be a simple matter of using your own version of the recipe. No recipe can tell you what the exact temp of your strike water needs to be, because of the different tanks, tuns, etc people use. For example, the water in my keg used to heat the strike water will get to the proper temp, but will actually continue to rise because the metal bottom is so hot. Then my mash is too high; I've had to cut the heat before reaching the dough in temp, them it will rise just enough to hit that target temp. Again, I take notes, and now it is no prob to do my recipe again.
Mash temp does matter, but like the guy said, a lower temp mash will be a dryer beer, where a higher temp mash results in a beer with a thicker, chewier mouthfeel yet lower in alcohol. Finally, if you're losing that much heat - is that mash tun insulated? I use a igloo 5 gal cooler, and I don't even have to leave the lid on it - the temp drops not a bit in 1 hr ! Merry Christmas, and a Happy New Beer !!!
 
hey mr sunshades... you do realize that he asked that almost 2 years ago? :)

Where are you in ball ground? I am in jasper and brew with guys in waleska and canton pretty regular. Would love to have you over to swap brews and what not. let me know.

:mug:
 
hey mr sunshades... you do realize that he asked that almost 2 years ago? :)

Where are you in ball ground? I am in jasper and brew with guys in waleska and canton pretty regular. Would love to have you over to swap brews and what not. let me know.

:mug:
Wow, I should look at those dates - still, I hope my post helps anyway!
I'm in an area known as Hightower, on 369 where Mnt Tabor Rd comes in from the L
as you're going towards 400. I do about 3-4 brews a year, and have my setup out on the back deck. I've got 2 little girls who take a lot of attention and love, so my homebrew has to wait sometimes! But I'd love to get together ... I have a couple of guys in my church who are brewers and am trying to plan a brew night with them, but like I said, family first! It's awesome though; I've had my daughter brewing with me before (she is 3 - I let her drop in the hops!) and my wife loves the brown ale, so life is good. Thanks for your reply, and I'll get some more pics of my rig on my profile, check em out!
 
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