The hop flower has been used in beer-making at least since the eighth century. Traditionally it was a preservative, but it also imparts flavor. To some, the taste is bitter and unpalatable, and thus many brewers use only minimal amounts. But, depending on variety, growing conditions, and other factors, hops can impart a range of flavors that connoisseurs say rivals that of wine grapes. Starting in the nineteen-seventies, small brewers on the West Coast began dramatically upping the amount of hops in their brews. One of their most popular products was the India pale ale, or L.P.A., a brew that has been around since the late eighteenth century. The story goes that necessity drove the British to add large quantities of hops in order to preserve the beer they shipped to India, to quench the thirst of the Sahibs managing the Empire there. Over the past decade, varieties once thought of as boutique beers, such as L.P.A.s, have exploded in the United States, thanks to the locavore movement. Craft brewing is now doubling in sales, by volume, every five years, today, craft-beer make up twenty-one percent of the beer market, and twelve percent of the volume. The Brewers Association, a craft-brewing trade group, expects craft beers to have a fifty-per-cent market share in a decade. Since craft brewers use about ten times more hops than megabrewers, the trend has been a bonanza for Hopsteiner and the other big hops companies. But while an emphasis on brewers to come up with new beer, which, in turn, leads to a hunt for new hops varieties.