DEFINITION OF MALT
If we had to describe what malt is in a nutshell, we could define it as a barley grain subjected to a germination process - under controlled conditions of temperature, humidity and oxygen - before it is dried and toasted.
The grain is the fruit of the barley plant, that is produced on the ear of the plant, where you can find the flower. There are two different types of barley, six or two rows, of which the latter is of higher quality and the most suitable for brewing.
In addition to barley, there are other cereals such as wheat, rye and oats that are also used - malted or raw - to brew beer. We will address these in a separate post.
THE MALTING PROCESS
Malting is a process prior to brewing that basically consists of the germination of the barley grain and its subsequent roasting. In this process we can distinguish three phases:
Soaking phase. The purpose of the soaking phase is to initiate germination, and for this, the cereal must be submerged in water. It usually lasts two days.
Germination phase. The purpose of this phase is to keep the grain under adequate conditions of humidity and ventilation that allow modifying its molecular structure and thus obtain the highest amount of fermentable sugars. This phase usually lasts five days.
Roasting phase. This phase is divided into two stages: drying and toasting. Here the objectives are on the one hand to stop the germination so that the embryo doesn’t consume the nutrients that will be necessary at a later stage in the process, and on the other hand, to reach the color and flavor required for each variety and/or style of beer.
MAIN GROUPS OF MALTS
Depending on the conditions in which the malting process is carried out, we can distinguish three large groups of malts, and within each group, different types that are classified according to their color range (EBC / SRM ...) and that vary according to the intensity of each toast.
Base Malts. The essential ingredient of the beer wort. They are obtained through a soft roast in order to preserve the enzymatic power. They are responsible for generating the necessary nutrients for the yeast to act. Among its main types we have the Pilsen, Pale, Vienna or Munich malts.
Caramel Malts. After germination, just before drying, the formation of sugars in the barley grain takes place. Thus, during roasting, caramelization of the interior is achieved, which gives rise to the reddish-colored wort, caramel flavors and nut aromas. Malts within this group are usually called Crystal malts or the prefix "cara" is added to the caramelized malt type, for example Carapils.
Roasted Malts. Dark colors and aromas of coffee, cocoa and burnt bread are obtained due to a toasting process at temperatures above 130ºC. These types of malts are referred to as Biscuit, Coffee, Chocolate or Black Malts, among others.
A final note: when roasting is carried out using coal, peat or firewood, in addition to the mentioned characteristics, the malts will also give a smoked touch to the beers.