The key difference between malted grain and unmalted grain lies in the process of malting. Malting is a crucial step in the production of many types of alcoholic beverages, including whisky. Here’s how malted grain and unmalted grain differ: Malted Grain: Malting Process: Malted grain, typically barley, goes through a malting process. During malting, barley grains are soaked in water to allow them to germinate. After a few days, germination is halted by drying the grains in a kiln. Enzyme Development: During germination, enzymes are activated within the barley grain. These enzymes, particularly amylase and protease, convert starches in the grain into fermentable sugars. This enzymatic activity is crucial for the fermentation process in brewing and whisky production. Flavour Development: Malting also contributes to the development of various flavours and compounds in the grain. The kilning process can influence the colour and flavour of the malted barley, contributing to the malt’s character. Whisky Production: In whisky production, malted barley is often used to make single malt whisky. The malted barley is mashed and fermented to create a wort, which is then distilled to produce whisky. Single malt whisky is known for its complex and often fruity or malty flavours, partly due to the malting process.   Unmalted Grain: Absence of Malting: Unmalted grain, such as corn, wheat, rye, or barley, does not undergo the malting process. Instead, it is used in its raw grain form. Starch Source: Unmalted grain primarily serves as a source of starch in the production of whisky. These grains have not undergone the enzymatic changes that occur during malting. Flavour Profile: Unmalted grains tend to contribute different flavours to the final product. For example, corn is known for its sweetness, while rye can add spiciness. Whisky Production: Unmalted grains are commonly used in the production of various types of whisky, including bourbon (which uses corn), rye whisky (which uses rye), and some blended Scotch whiskies (which can include unmalted barley or other grains). These grains are typically mashed, fermented, and distilled to create the base spirit.   In summary, the main difference between malted grain and unmalted grain is the malting process. Malted grain undergoes germination and enzymatic changes, resulting in the development of sugars and complex flavours. Unmalted grain is used in its raw form and primarily provides starch for fermentation, contributing different flavour characteristics to the final product. The choice of grain, malted or unmalted, plays a significant role in shaping the flavour and character of whisky.