What substance is beerstone primarily composed of?

Beerstone is primarily composed of protein and calcium oxalate, which often forms during the brewing process. It is a byproduct that can accumulate on brewing equipment, particularly in areas where there is a combination of proteins and minerals present.

Most notably, the formation of beerstone occurs when beer is cooled or when it undergoes fermentation, leading to the precipitation of calcium oxalate and protein interactions. This substance can be detrimental to brewing operations as it may cause issues with cleaning and sanitation, affecting the overall quality of the beer.

In contrast, other substances such as calcium carbonate, sodium chloride, and magnesium sulfate do not form the same kinds of deposits associated with beerstone and do not play the same role in brewing sanitation issues. Therefore, recognizing that beerstone is specifically composed of protein and calcium oxalate is crucial for understanding its impact on the brewing process and equipment maintenance.