Mash Thickness

The thickness of the mash can have varying impacts on how the beer turns out. It is important to remember that temperature readings need to be taken in as many places in the mash bed as possible, and to stir and evenly distribute temperature so as to avoid hot spots.

Water:Malt Mash Ratios



Medium Thick
1.25:1  1.5:1  1.75:1

1.25     1.5     1.75
1           1        1
2:1  2.25:1  2.5:1

2     2.25     2.5
1      1          1

Here is a summary chart on the Pros and Cons of Mash Thickness


Thick Mash

Enzymes are very stable, even if mash temperature is greater than published optimal temps

Extract yield may suffer because of product inhibition. thick mashes are hard to stir and pump.
Medium-Thick Mash

Good extract yield, easy to stir and pump. product inhibition (build-up that slows important chemical reactions) is not a concern.

Enzymes are less stable at high temperatures compared to thick mashes. Overshooting target temps can cause problems
Thin Mash

Good extract yield, easy to stir and pump. Product inhibition that slows chemical reactions is not a concern.

Enzymes arre very sensitive to high temperatures in thin mashes. Overshooting target temperature causes quick denaturation of enzymes.