As a sommelier and brewer, I can provide you with some insights on whether or not you need a protein rest in your brewing process. A protein rest is a step in the mashing process where the temperature is held at a specific range to encourage the breakdown of proteins in the grain. This can help improve the overall quality of your beer, especially when using unmalted grains or less modified malts like Munich.
If your grist consists of 25% or more unmalted grains, such as flaked wheat or oats, then performing a protein rest is highly recommended. Unmalted grains have higher levels of proteins that can lead to haze and poor foam stability in the finished beer. By conducting a protein rest, you can help break down these proteins and reduce the likelihood of these issues.
German malts, like Munich, could also benefit from a protein rest since they are typically less modified than American grains. Munich malt is known for its rich, malty flavors, but it can also have higher protein levels. By incorporating a protein rest, you can ensure that the proteins in the Munich malt are properly broken down, resulting in a smoother and cleaner beer.
I have personally experienced the difference a protein rest can make in brewing. In one of my batches, I used a significant portion of flaked oats in the grist without performing a protein rest. The beer turned out quite hazy and had a less than desirable foam stability. However, in subsequent batches, I included a protein rest at around 122°F (50°C) for about 20 minutes, and the results were noticeably improved. The beer had a clearer appearance and a more persistent foam.
It is important to note that not all beers require a protein rest. If your grist consists primarily of well-modified malts, such as pale or pilsner malts, the protein levels are typically lower, and a protein rest may not be necessary. Additionally, some brewing techniques, like using a high percentage of wheat malt, can also contribute to increased protein breakdown without the need for a specific protein rest step.
If you are using a significant amount of unmalted grains or less modified malts like Munich, it is highly recommended to perform a protein rest. This step can help break down proteins and improve the overall quality of your beer. However, it is essential to consider the specific characteristics of your grist and brewing technique to determine if a protein rest is necessary in your particular situation.