A little-known process that's key for brewing

Malting barley begins with a good soaking of the grain.

Maltsters like Rahr then germinate barley in sprawling malt houses that smell a bit like alfalfa sprouts or fresh-cut cucumbers. Either way, it's a heady organic aroma.

After barley is germinated in long boxes, it's dried in a kiln. The whole process takes seven days. Malted barley provides the enzymes and starches needed to create fermentable sugars. So, it plays a starring role in beer fermentation, along with yeast.

But despite its importance to beer, barley as a crop has been falling out of favor with U.S. farmers, sending worries through the brewing industry. For farmers, corn and soybeans can pay more and entail less risk than barley. So, barley acreage in the U.S. has declined significantly.

"It's a critical issue, the supply, the security of supply of malt and barley," said William Rahr, Rahr Malting Co.'s president.