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Malt and Malting
Pale Ale malt used to brew beer is prepared from barley in a maltings.
Certain varieties of barley are grown specially for malting and are purchased by maltsters or seed merchants to very tight specifications.
After a period of storage or resting which ensures all the corns are ready to germinate at the same time, the barley is steeped in water in large vessels called “steeps” until it germinates and starts to grow. At this point the germinating barley is transferred to one of a variety of different systems depending on the size and complexity of the maltings.
Or one of a number of other possible systems.
Whatever system is used the purpose is to keep the malt grains moving to ensure that conditions of moisture, oxygen content and temperature are even across all of the malt. The movement also serves to prevent the developing rootlets from meshing together and forming a solid mat of malt.
During this period of growth, which takes about 4 or 5 days, the barley seedling starts to grow. The rootlets are the first obvious sign but the developing seedling starts to grow from the base of the seed under the outer skin and would eventually break out through the top of the seed.
As it grows, the seedling produces a number of enzymes, which, in the normal course of events had the seed been growing in the soil, would break down the barley starch into sugars. These sugars would be used as a source of energy for the seedling’s growth until such time as it was able to open its leaves and absorb the sunlight.
However, when there has been just the right amount of growth, meaning the optimum amount of enzymes have been produced, the maltster transfers the “green” malt, as it is called at this stage, to a kiln where the malt is dried off with a carefully controlled temperature regime over a number of hours, in such a way that most of the moisture is driven off, the developing seedling is killed but the enzymes it produce are preserved. The end result is a little packet of starch in the shape of a malt corn, containing all the enzymes necessary to break the starch down into sugars.
There a a number of different styles of malt produced with varying properties of colour and flavour. At Broughton we use Crystal Malt, Black Malt and Roasted Barley.
Crystal Malt is produced by kilning the green malt under much higher temperatures. This facilitates the “browning reaction” which is a reaction between amino acids and sugars in the malt resulting in a very biscuity, malty, flavour and aroma as well as a higher colour. Crystal malt is used to enhance the malt flavour and aroma in beer as well as to produce a ruby colour as seen in Black Douglas which calls for a fairly high proportion of crystal malt.
By varying the kiln conditions of time and temperature a range of malts can be produced with varying colours and flavours.
{Image of various malts}
Black malt is produced by roasting pale ale malt in an oven. Again variations of colour and aroma can be produced by different temperatures and times of roasting. Black malt produces a very intense brown colour in beer and also has what is compared to a very bitter dark chocolate flavour.
Roasted barley, as you would, expect is simply barley roasted in an oven until it turns black. Roasted barley produces a similar colour effect to black malt but the flavour is more reminiscent of roasted coffee.
At Broughton Ales the best example of the use of roasted barley and black malt is in Scottish Oatmeal Stout where a high proportion is used to produce a rich roasted coffee, bitter chocolate flavour.
