Describe the method used to calculate theoretical alcohol potential from a mash.

Calculating the theoretical alcohol potential from a mash involves determining the maximum amount of alcohol that can be produced based on the amount of fermentable sugars present in the wort. The method relies on understanding the stoichiometry of fermentation, which is the quantitative relationship between reactants and products in a chemical reaction. The primary fermentation reaction converts glucose (a simple sugar) into ethanol (alcohol) and carbon dioxide, according to the equation: C6H12O6 → 2 C2H5OH + 2 CO2. This means that one molecule of glucose yields two molecules of ethanol and two molecules of carbon dioxide. First, the specific gravity of the wort is measured using a hydrometer or refractometer before fermentation begins. Specific gravity is the ratio of the density of the wort to the density of pure water. From this, the original gravity (OG) is obtained. The OG represents the total amount of dissolved solids in the wort, primarily sugars. Next, the final gravity (FG) is measured after fermentation is complete, again using a hydrometer or refractometer. The FG represents the amount of residual unfermented sugars and other non-fermentable compounds remaining in the wort. The difference between the OG and FG provides an indication of the amount of sugar that was fermented. The theoretical alcohol potential, expressed as alcohol by volume (ABV), can then be estimated using a formula. A commonly used formula is: ABV = (OG - FG) 131.27. In this formula, OG and FG are expressed as specific gravity values, and the result is the approximate ABV percentage. The constant 131.27 is an empirically derived factor that accounts for the conversion efficiency of sugars to alcohol. This calculation provides a theoretical maximum ABV, assuming complete fermentation of all available fermentable sugars. In practice, the actual ABV may be slightly lower due to factors such as yeast health, fermentation conditions, and the presence of non-fermentable sugars. Therefore, while the theoretical alcohol potential provides a useful estimate, it's important to consider other factors that can influence the final ABV of the beverage.