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Drying the hops

The buildings used for drying hops in the Midlands counties have always been called kilns and not oast houses as they are in Kent. In the beginning there were no purpose-built hop kilns and the hops were dried in specially adapted malt kilns.

In the 17th century in Herefordshire the type of hop kiln found in Herefordshire was a small brick fireplace about 3ft square, with an inverted lath and plaster cone drawing the hot air up to a drying floor some 8ft square. By the 18th century, as the hop industry grew, specially-designed kilns were built with most hop farmers having their own.

Circular kilns were built for economic reasons as they had no "cold corners" and were thought to spread the heat more evenly. Later, it was found that square kilns could hold sufficient heat and they were easier to build and work in. It was in the 18th century that the conical cowl was added to the roof of the kiln. In the beginning this was wooden, between 9-15ft tall and usually painted white. It had an opening on one side with a fixed arm vane, which swung against the wind. The cowl covered a gap about 3ft wide in the top of the kiln's cone-shaped roof, and it allowed the hot air to escape.

In the mornings the wagons would bring in the freshly-picked hops in sacks which held between 8 and 10 bushels each. The hops were taken to the kiln as quickly as possible before they started to lose their colour and flavour. Most kilns had a door on the first storey at the same height as the wagon trailer so that the hops could be unloaded directly into the kiln.

The method of drying the hops was via a natural warm air draught. A fire was kept burning in a chamber, called the plenum, situated below the drying floor. The warm air would rise up to the hops on the floor above, which were spread out on hessian. The floor of the drying room would have gaps in it to allow the air to get to the hops. Originally the fire was kept going with wood or charred turf but later charcoal was used. One hundred sacks of charcoal were needed to dry one ton of hops. Particular attention was paid to the temperature in the plenum and if it got too high cold air was allowed in to bring it back down. The general rule was that the starting temperature should not be more than 100º Fahrenheit (38º Centigrade), rising steadily to 140º Fahrenheit and never going above 160º Fahrenheit.

When cast iron furnaces were introduced farmers were able to use cheaper fuel as any gases harmful to the hops could be channelled away.

The drying room had a thin floor of wooden slats with one inch gaps in between. The floor was covered in horse-hair or hessian cloth. In recent times this covering has been replaced with a synthetic floor covering, and some modern kilns have two or even three drying floors.

During the first hour of drying the hops retained their colour and moisture. Sulphur was burnt to pass through the green hops and bleach them a yellowish tint. The sulphur was said to improve the aroma but it also helped to hide any discolouration from diseases or bruising and helped to preserve the hops.

The men who worked the furnaces and dried the hops at one time stayed in the kilns for 24 hours a day, with only short weekend breaks. At about 2am the drier's day would start with him waking to turn the hops. To turn the hops without damaging them the driers used a wide flat wooden paddle called ascruppet. By evening the hops would be dry. The drier would test the progress of the hops by rubbing them between his fingers, and if they were sufficiently dry they would become a powder. If they were not dry they would feel sticky when rubbed.

In the 1930s fans in kilns came into general use. These moved the hot air round the kiln more efficiently and so sped up the drying process.

After the hops had been dried they were moved from the drying floor to the cooling room. The hops had retained a small amount of moisture and they were left to cool, which could take up to a day. The moisture and the slow cooling meant that the hops became soft and supple rather than dry and brittle.

After cooling the hops would be loaded into pockets (very large, long sacks) and compressed down firmly to ensure that they would survive storage and transport. The easiest way to fill the pockets was to have a hole cut in the floor and the pocket would hang from this hole with the weight of the pocket supported by a sling. When full, the top of the pocket would be stitched up. The sides of the pocket were stamped with the grower's name and address. Each pocket held around one and a half hundredweight. In 1774 a law was passed that stated that the weight should be stamped on the pocket, as well as the year. In 1838 it became law for the hop pockets to be made out of five yards of hessian cloth, and also that they should be 42-45 inches wide.

At the end of the picking season there was much celebration and parties were held on the majority of hop farms. There would be singing and dancing and plenty of drinking before the families packed up their belongings and boarded the trains back to the towns.

[Original author: Miranda Greene, 2005]