Cooler mash tun & low OG

[sa1126]

I am using a small three gallon cooler for some one gallon batches. It has been a lot of fun and a great way to beat the Texas heat. I've had some low starting gravity despite using beer smith for all calculations and believe it is probably a low mash temp.

What do you guys use for thermometers in the coolers?

Say the mash temp does drop below a certain point say 30 minutes into the batch. What would the course of action be to raise it?

 

[Uintafly]

I always keep hot water nearby at strike time, in case I undershot it. My cooler setup never drops more than 2 degrees over the course of my 70 minute mash so I don't worry about it after strike time, but I can't think of any reason why it wouldn't work halfway through.

 

[jlangfo5]

I would first recommend "calibrating" your thermometer. Drop it into some boiling water for about half a minute and see what it reads, then do the same for a glass of water with lots of ice that has had about 10 minutes to sit.

If the thermometer is reading to reading to high and making you mash to low, you might not be mashing long enough to convert all of your starches into sugars since it takes quite some time to complete conversion at lower temperatures.

You can try using an iodine test to see if there is still starch in your wort to tell if it has completed or not.

If your temperature is dropping low in the mash, you remove a gallon of the thickest part of the mash, heat it to 155 or so for about 10 minutes, then bring it to boiling and add it back to the mash tun to raise the temperature of your mash. Then stir the mash until it drops back down to your target temperature and let it sit like normal

 

[sa1126]

Awesome thanks. What do you all recommend for thermometers?

 

[FuriousE]

Low mash temp shouldn't really impact your OG (unless you are REALLY low).

Did you calibrate Beersmith for your particular setup's efficiency?

I use the thermapen. Pricey at about $100, but it is the gold standard and its great for grilling as well.

 

[duboman]

+1 on the thermapen!

I would start by evaluating your crush and double checking your equipment settings in BS. Then water and pH of the mash.

You also need to be sure your volumes pre-boil are spot on as you could be oversparging and diluting or leaving a lot of tasty wort behind.