Mash in temperature was supposed to be 152 degrees. I forgot to adjust for temperature loss add simply mixed my grains with 152 degree water. I never calculated the final temperature.

I did the same thing with the batch sparge (poured in 175 degree water).

How will the affect my final product?

  • Did you measure the actual mash temp after adding grains to the water?
    – mdma
    Commented Oct 27, 2013 at 17:58
  • I did not. I believe in my setup I should've lost about 9 degrees.
    – Greg
    Commented Oct 27, 2013 at 18:02

1 Answer 1


The beer will probably be drier, since I imagine your final mash temperature was in the range of 140-145°F - lower mash temps produce drier beer since there is a greater portion of fermentables. You may also lose body, since the temperature is not optimal for alpha amylase, which produces body enhancing dextrins, and is also close to the protein rest, so proteins may also have been broken down in the mash, causing a thinner body and reduced head.

The lower temperature for batch sparging doesn't really make much difference. In theory, lauter efficiency is slightly higher, but I doubt you'd notice difference in practice.

In future, if you do undershoot your target mash temperature, just stir in some boiling water until the temperature comes up to where you want it. Alternatively, you can decant 1/4 of the mash, bring it to the boil, and then return it to the mash.

  • So this won't affect ABV?
    – Greg
    Commented Oct 27, 2013 at 18:01
  • It shouldn't as long as you got conversion. It takes longer to convert at lower temps so a 90 min, mash would have been ideal. But even with a 60 min. mash, today's highly modified malts should be able to convert at low temps.
    – Denny Conn
    Commented Oct 27, 2013 at 18:05

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.