What is dispersion and hydration?

There are a couple of terms and concepts that you will often find related to modernist cooking. Just as you’ve mentioned, dispersion and hydration are two of these. Many of us aren’t physics majors, and it really helps to understand these terms and concepts in the easiest way possible.

Dispersion is the method used to evenly spread out one single ingredient into another. It is basically mixing together two different ingredients and making sure that it is properly distributed and there are no clumps in the mixture.

Dispersion is the method that is used when you add cornstarch or flour into water or some other liquid. This simple process is an important one because it helps you make sure that the ingredient being mixed in affects all areas of the other ingredient. In short, you want all of that flour, cornstarch or whatever, mixed right into your liquid, and the like.

Hydration on the other hand, as its name implies has to do with hydrating or combining something with water. This method is all about mixing ingredients with water. Many ingredients used in molecular cooking need to be mixed with water when being used. Aside from being mixed with water, some may also need to be heated to activate certain properties in it.