Malted grains are a key ingredient in whisky making. Whether used as the primary grain or as a supplemental ingredient to aid in fermentation, malted (or sprouted) grains provide a wellspring of fermentable sugars. The history of malting stretches back to ancient Egyptian brewing culture. In Scotland, the use of malted grains in distilling dates back to at least 1494, when the first mention of barley malt appears in tax records.

Malting Their Own

While in-house malting floors were the norm before the rise of independent maltsters, some distilleries—including Laphroaig and Bowmore on Islay, and Balvenie in Speyside—have their own malting floors.

Malt Shops

Globally, Boortmalt is the largest provider of malted grains, with two plants in Scotland. Diageo’s Port Ellen on Islay and Glen Ord in Muir of Ord, among other malting plants, are also major suppliers. In the U.S., Great Western Malting supplies a huge amount of malted barley from its Washington and Idaho facilities.

Barley Is King

Barley is overwhelmingly the most malted grain in the whisky world, so what are the other grains?

In second place would be rye. American examples are Old Potrero Single Malt Rye and New Riff Malted Rye, both of which are made from 100% malted rye. Malted wheat is a rarer choice, but Hye-Land Armenian whisky fits the bill.

How Malting Happens

To start, a grain—most often barley—is steeped in water. During the soak, enzymes within the grain turn carbohydrates into fermentable sugar.

When malting barley, the prepared grain is called green malt. At this point, the green malt is allowed to germinate and sprout.

Once the barley has sprouted, it is then kilned or heated by warm air. This process dries the grain and prevents further germination. ■