Malthouse - Production Process

Production Process

The grain was first soaked in a steeping pit or cistern for a day or more. This was constructed of brick or stone, and was sometimes lined with lead. It was rectangular and no more than 40 inches (100 cm) deep. Soon after being covered with water, the grain began to swell and increase its bulk by 25 percent.

The cistern was then drained and the grain transferred to another vessel called a couch, either a permanent construction, or temporarily formed with wooden boards. Here it was piled 12–16 inches (30–41 cm) deep, and began to generate heat and start to germinate. It spent a day or two here, according to the season and the maltster's practice.

It was then spread out on the growing floor, the depth dictated by the temperature, but sufficiently deep to encourage vegetation. It was turned at intervals to achieve even growth and over the next fourteen days or so it is turned and moved towards the kiln. The temperature was also controlled by ventilation. A day or two after the grain was turned out on to the floor, an agreeable smell was given off, and roots soon began to appear. A day or so later the future stem began to swell, and the kernel became friable and sweet-tasting. As the germination proceeded the grain was spread thinner on the floor. The process was halted before the stem burst the husk. At this stage much of the starch in the grain had been converted to maltose and the grain was left on the floor to dry. The art of malting depends on the proper regulation of these changes in the grain. Maltsters varied in their manner of working, and adapted to changes in climatic conditions.

The barley was then moved into the kiln, 4–6 inches (10–15 cm), for between two and four days, depending on whether a light or dark malt was required. A slow fire was used to start, and then gradually raised to suit the purpose of the malt and the desired colour. The barley was then sieved to remove the shoots and stored for a few months to develop flavour.