To achieve a crisp, dry finish in beer, which compound should be added?

Calcium sulfate, also known as gypsum, is commonly used in brewing to enhance the perception of dryness and crispness in beer. By adding calcium sulfate to the brewing water, brewers can increase the sulfates relative to the calcium levels, which accentuates the bitterness of hops and creates a drier finish. This is particularly beneficial in styles that prioritize hop character, such as IPAs.

Sulfate ions in the brewing water have been found to accentuate the hop bitterness, allowing the flavors to stand out more prominently without adding sweetness, which contributes to the overall crispness of the beer. The balance of mineral content, specifically increasing sulfates while maintaining appropriate levels of calcium, can significantly affect the mouthfeel and finish of the beer, making it feel drier and cleaner on the palate.

In contrast, calcium carbonate, sodium chloride, and magnesium sulfate are not ideal choices for achieving a crisp, dry finish. Calcium carbonate adds alkalinity and can leave a sweeter, maltier finish due to the buffering effect it has on the pH in the mash, thus not favoring the desired dryness. Sodium chloride, or table salt, tends to enhance sweetness and body, which would detract from the crispness desired in the final product. Magnesium