Hops


Hops are the flowers of the hop plant Humulus lupulus, a member of the Cannabaceae family of flowering plants. They are used primarily as a bittering, flavouring, and stability agent in beer, to which, in addition to bitterness, they impart floral, fruity, or citrus flavours and aromas. Hops are also used for various purposes in other beverages and herbal medicine. The hops plants have separate female and male plants, and only female plants are used for commercial production. The hop plant is a vigorous climbing herbaceous perennial, usually trained to grow up strings in a field called a hopfield, hop garden, or hop yard when grown commercially. Many different varieties of hops are grown by farmers around the world, with different types used for particular styles of beer.
The first documented use of hops in beer is from the 9th century, though Hildegard of Bingen, 300 years later, is often cited as the earliest documented source. Before this period, brewers used a "gruit", composed of a wide variety of bitter herbs and flowers, including dandelion, burdock root, marigold, horehound, ground ivy, and heather. Early documents include mention of a hop garden in the will of Charlemagne's father, Pepin the Short.
Hops are also used in brewing for their antibacterial effect over less desirable microorganisms and for purported benefits including balancing the sweetness of the malt with bitterness and a variety of flavours and aromas. It is believed that traditional herb combinations for beers were abandoned after it was noticed that beers made with hops were less prone to spoilage.

History

The first documented hop cultivation was in 736, in the Hallertau region of present-day Germany. In 768, hop gardens were left to the Cloister of Saint-Denis in a will of Pepin the Short, the father of Charlemagne. The first mention of hops being used in German brewing was in 1079.
Not until the 13th century did hops begin to start threatening the use of gruit for flavouring. Gruit was used when the nobility levied taxes on hops. Whichever was taxed made the brewer then quickly switch to the other.
In Britain, hopped beer was first imported from Holland around 1400, yet hops were condemned as late as 1519 as a "wicked and pernicious weed".
In Germany, using hops was also a religious and political choice in the early 16th century. There was no tax on hops to be paid to the Catholic church, unlike on gruit. For this reason the Protestants preferred hopped beer.
Hops used in England were imported from France, Holland and Germany and were subject to import duty; it was not until 1524 that hops were first grown in the southeast of England, when they were introduced as an agricultural crop by Dutch farmers. Consequently, many words used in the hop industry derive from the Dutch language. Hops were then grown as far north as Aberdeen, near breweries for convenience of infrastructure.
According to Thomas Tusser's 1557 Five Hundred Points of Good Husbandry:
In England there were many complaints over the quality of imported hops, the sacks of which were often contaminated by stalks, sand or straw to increase their weight. As a result, in 1603, King James I approved an Act of Parliament banning the practice by which "the Subjects of this Realm have been of late years abused &c. to the Value of £20,000 yearly, besides the Danger of their Healths".
Hop cultivation was begun in the present-day United States in 1629 by English and Dutch farmers. Before prohibition, cultivation was mainly centred around New York, California, Oregon, and Washington state. Problems with powdery mildew and downy mildew devastated New York's production by the 1920s, and California only produces hops on a small scale.

World production

Hops production is concentrated in moist temperate climates due to the plant's needs, with much of the world's production occurring near the 48th parallel north. Climate change may impact future commercial production. Germany and the United States account for three quarters of hop production with two thirds of the total surface area used for hop-growing worldwide. Hop plants prefer the same soils as potatoes and the leading potato-growing states in the United States are also major hops-producing areas. Not all potato-growing areas can produce good hops naturally, however: for example, soils in the Maritime Provinces of Canada lack the boron that hops prefer. Historically, hops were not grown in Ireland, but were imported from England. In 1752 more than 500 tons of English hops were imported through Dublin alone.
Important production centres today are the Hallertau in Germany, the Žatec in the Czech Republic, the Yakima and Willamette valleys, and western Canyon County, Idaho. The principal production centres in the UK are in Kent, Herefordshire, and Worcestershire. Essentially as almost all the harvested hops are used in beer making the notable worldwide producers are orientated towards this market. Other notable regions for international market in beer hops not mentioned so far include Spalt and Tettnang in Germany, Lublin in Poland, Celje in Slovenia, Derwent Valley, Tasmania and High country of Victoria in Australia, Marlborough in New Zealand, Villanueva del Carrizo in Spain, George in South Africa. Countries with notable production include China, France, Japan, Canada, Chile, Argentina and the Ukraine.
File:Yakima-Valley-Hop-Yard.jpg|thumb|right|Early season hop growth in a hop yard in the Yakima River Valley of Washington with Mount Adams in the distance
Hop producing country2020 hop output in tonnes
United States47,541
Germany46,878
China7,044
Czech Republic5,925
Poland3,417
Slovenia2,723
Australia1,714
New Zealand1,250
UK/England924
Spain908
France767

Cultivation and harvest

Although hops are grown in most of the continental United States and Canada, cultivation of hops for commercial production requires a particular environment. As hops are a climbing plant, they are trained to grow up trellises made from strings or wires that support the plants and allow them significantly greater growth with the same sunlight profile. In this way, energy that would have been required to build structural cells is also freed for crop growth.
The hop plant's reproduction method is that male and female flowers develop on separate plants, although occasionally a fertile individual will develop which contains both male and female flowers. Because pollinated seeds are undesirable for brewing beer, only female plants are grown in hop fields, thus preventing pollination. Female plants are propagated vegetatively, and male plants are culled if plants are grown from seeds.
Hop plants are planted in rows about apart. Each spring, the roots send forth new bines that are started up strings from the ground to an overhead trellis. The cones grow high on the bine, and in the past, these cones were picked by hand. Harvesting of hops became much more efficient with the invention of the mechanical hops separator, patented by Emil Clemens Horst in 1909.
Hops are harvested at the end of summer. The are cut down, separated, and then dried in an oast house to reduce moisture content. To be dried, the hops are traditionally spread out on the upper floor of the oast house and heated by heating units on the lower floor. The dried hops are then compressed into bales by a baler. They are now usually dried in kilns with large fans that force clean, heated air, through the hop beds and futher processed into pellets which have longer storage properties than whole hops.
Hop cones contain different oils, such as lupulin, a yellowish, waxy substance, an oleoresin, that imparts flavour and aroma to beer. Lupulin contains lupulone and humulone, which possess antibiotic properties, suppressing bacterial growth favoring brewer's yeast to grow. After lupulin has been extracted in the brewing process the papery cones are discarded.

Migrant labor and social impact

The need for massed labour at harvest time meant hop-growing had a big social impact. Around the world, the labour-intensive harvesting work involved large numbers of migrant workers who would travel for the annual hop harvest. Whole families would participate and live in hoppers' huts, with even the smallest children helping in the fields. The final chapters of W. Somerset Maugham's Of Human Bondage and a large part of George Orwell's A Clergyman's Daughter contain a vivid description of London families participating in this annual hops harvest. In England, many of those picking hops in Kent were from eastern areas of London. This provided a break from urban conditions that was spent in the countryside. People also came from Birmingham and other Midlands cities to pick hops in the Malvern area of Worcestershire. Some photographs have been preserved.
The often-appalling living conditions endured by hop pickers during the harvest became a matter of scandal across Kent and other hop-growing counties. Eventually, the Rev. John Young Stratton, Rector of Ditton, Kent, began to gather support for reform, resulting in 1866 in the formation of the Society for the Employment and Improved Lodging of Hop Pickers. The hop-pickers were given very basic accommodation, with very poor sanitation. This led to the spread of infectious diseases and led to contaminated water. The 1897 Maidstone typhoid epidemic was partly as a result of hop-pickers camping near the Farleigh Springs which supplied Maidstone with water.
Particularly in Kent, because of a shortage of small-denomination coin of the realm, many growers issued their own currency to those doing the labor. In some cases, the coins issued were adorned with fanciful hops images, making them quite beautiful.
In the United States, Prohibition had a serious adverse effect on hops production, but remnants of this significant industry in the western states are still noticeable in the form of old hop kilns that survive throughout Sonoma County, California, among others. Florian Dauenhauer, of Santa Rosa in Sonoma County, became a manufacturer of hop-harvesting machines in 1940, in part because of the hop industry's importance to the county. This mechanization helped destroy the local industry by enabling large-scale mechanized production, which moved to larger farms in other areas. Dauenhauer Manufacturing Company remains a current producer of hop harvesting machines.