Malted barley comes in two basic categories: 2-Row and 6-row. Each variety has its own sets of pro’s and cons in terms of yield, enzymatic content, and flavor. Here’s what you need to know, if you want to make malted barley part of your whiskey grain bill.
2-Row malted barley has better/more flavor than 6-row.
2-Row malted barley has slightly better yield than 6-row.
6-Row has much more enzymes available than 2-row. A 20% contribution of 6-row converts its own starches as well as the remaining 80% of unmalted grains. A 40% contribution of 2-row is needed to convert its own starches as well as the remaining 60% of unmalted grains.
Use 2-row if you are after the flavor of malted barley. Use 6-row if you want to highlight the flavors of the unmalted grains in your grain-bill, like corn, rye, wheat or oats.
Single malt whisky is made up solely of malted barley. Since any type of malted barley has enough enzymatic power for its own starch conversion, choose 2-row. It has more flavor (more depth and more smoothness) and slightly better yield.
Bourbon style whiskies want to highlight sweet corn flavors. If you want to use malted barley, it will be to convert the corn starches into fermentable sugars. Use 6-row malted barley, because of its higher enzymatic content and conversion power. 6-Row also has less of a flavor impact, leaving room for the corn to shine.