Hops could be classified as a useless plant if not for its role in brewing. Hops is a basic ingredient for beer.
Beer is essentially four basic ingredients: water, malt, yeast and hops that are boiled, cooled and stored to ferment.
The last, hops, are the flowering cone of a viney plant related to cannabis. But without any of the drug that makes marijuana popular. It can be grown in almost any climate with adequate water and sunlight and the vine sometimes reaches as high as 40 feet.
Hops, clever use for a useless plant
Beer can be, and historically was, made without one of its now-primary ingredients - hops. First used in Europe around 1100 AD, hops help to produce more beer from the same amount of malt.
Hops act as a preservative, flavoring agent - where it adds a bitter taste to offset the sweetness of malt sugar (maltose) - and it adds an aroma that can vary from piney to citrus-like.
As a preservative, it allows for lower alcohol content to be present, while helping keep the beer fresh enough to be drunk after more than a few weeks. Since the alcohol is the product of fermentation of barley grain, adding hops allowed for the use of less grain to make the same amount of brew. That helps lower the grain portion of the cost of producing it.
As a flavoring agent hops contribute in multiple ways. The fruit of the hop plant contains compounds called alpha acids. When they're heated they become bitter (a common characteristic of some acids).
At the same time, like many plants, hops contain oils that add distinctive aromas. Aroma and taste are closely intertwined and the addition of a herbal or pine-cone like smell can influence the perceived taste of the final product.
Since those oils vaporize readily during heating, additional hops are frequently added during the brewing process, sometimes at the end solely to add additional aroma and flavor. The technique is common in ales, contributing to their more heady nose and flavor over many lagers.
Hops even possess a mild antibiotic that helps suppress some of the organisms in the wort (the liquid fermented to make beer), allowing the yeast to carry out the fermentation process more efficiently.
Their use in brewmaking began around the beginning of the 12th century in Germany. From there the practice spread to Britain in the early 16th century. Scottish ales began using hops only much later. They won't grow in the cold climate. The technique was adopted in the United States in 1629.
Given that geographic variety and long history, it's not surprising that today there are several dozen basic varieties of hops and many hundreds of sub-types.
Noble hops alone, for example, come in four types. Low in bitterness and high in aroma, they hail from Central Europe and have exotic names like Saaz and Spalter, Tettnanger and Hallertau. The names derive largely from their region of origin.
Names more familiar to English readers, but derived from their European ancestors, are such types as Goldings - an English hop used in some ales - and Fuggles, a woody hop developed in England in the late 19th century.
But several countries are represented: Hersbrucker, a German used in pale lagers and Lublin from Poland. There's even the Pacific Gem, a berry-aroma type from New Zealand.
Since hops have practically no commercial use beyond their application to beer making, the world is fortunate that clever brew meisters exist that can turn a limitation into such delightful advantage. Raise a glass in salute.