What is the term for using only fresh water in the cooking process of bourbon production?

The term "Sweet Mash" refers to the process in bourbon production where only fresh water is used during the cooking stage. In this method, the mash bill, which is the mixture of grains (typically corn, rye, barley, etc.), is combined with fresh yeast and water without including any previously fermented mash. This contrasts with "Sour Mash," where a portion of mash from a previous distillation, which contains residual yeast and bacteria, is added to the new mash. This difference in the fermentation process between Sweet Mash and Sour Mash has significant implications for the flavor and characteristics of the final bourbon product. Sweet Mash is often associated with a cleaner and more controlled fermentation, which can lead to a somewhat sweeter and purer flavor profile in the bourbon.