The Egyptians were brewing beer in 4000 BC and artifacts in the Cairo museum show that it had already evolved into a disciplined technology by the third millenium BC. Beer can be brewed from a range of cereals, but by the 17th century beers brewed from barley malt predominated in Europe. With the expansion of trade and the discovery of the New Worlds, making beer from barley malt spread across the globe. Currently, approximately 1,400 Million Hectolitres of beer are brewed annually around the world. World malt production stands at approximately 17,500, 000 tons.
What is Malt?
Malt is a very convenient package. 60-65% of the weight of malt is undegraded starch. Barley is deficient in certain key enzymes (eg a-amylase) and malting increases these levels. During brewery mashing the malt enzymes are mixed with starch to produce maltose and other fermentable sugars. Malt also provides various nutrients for yeast growth, including amino acids, vitamins and minerals. Malt provides the proteins that produce the beer foam that clings enticingly to the glass. The husk of barley malt provides the filter bed, crucial for forming clear worts during lautering.
The Malting Process
Perhaps the most important stage of malting is barley procurement. Bairds Malt procures more than 85% of its malting barley at harvest time. Only malting grade barley is purchased. It is very carefully inspected on intake, dried in our own driers and segregated by variety. The storage conditions are very carefully controlled and monitored and barley is only released for malting when it has reached its optimum vigour.
When a barley corn germinates in the field, the embryo and the aleurone layer produce enzymes that pass into the starchy endosperm breaking down cell walls and the protein matrix. The endosperm loses its hard structure and becomes "modified". Starch is then hydrolysed to simple sugars (eg maltose). Nutrients pass from the starchy endosperm into the embryo and support the growth of a new plant. Malting is the limited germination of the barley grain under very carefully controlled conditions. The maltster ensures that all the corns germinate and at the same rate. Good levels of enzymes are produced. The cell walls of the starchy endosperm are degraded and the protein matrix is disrupted. The maltster the arrests germination by kilning to ensure that very little of the starch is hydrolysed. Conversion of starch to maltose occurs in the brewery mashing process.