What temperature range is ideal for a protein rest during mashing?

The ideal temperature range for a protein rest during mashing is 113-138°F. This temperature range is critical for facilitating the breakdown of proteins into smaller peptides and amino acids, which can enhance the body and mouthfeel of the beer. During this rest, enzymes such as proteases become active, cleaving larger proteins that can promote haziness if not managed properly. This also helps in improving the overall head retention and stability of the final beer.

Lower temperatures, like those in the 100-110°F range, do not activate these enzymes effectively, while the ranges above 138°F start to favor the activity of enzymes involved in starch conversion, such as alpha-amylase, rather than protein breakdown. Therefore, the range of 113-138°F strikes the proper balance needed for effective protein rest.