Although modern laboratories have been established in malt houses over the past few decades, the latest technological solutions have been introduced, and many tasks have been automated, the malting process itself has essentially remained unchanged for hundreds of years. This is because malting makes use of natural transformations occurring in the grain under conditions involving access to water, oxygen, and the appropriate temperature, aimed at stimulating growth processes. However, the purpose of malting is not to produce shoots, leaves, and ears. Its aim is to halt the development of the embryo at the right moment: when the sugars accumulated in the grain become accessible to the enzymes released during germination. If this process is interrupted too early or too late, the desired result will not be achieved. The most important changes occurring during malting include: an increase in the amount of enzymes present in the grain, partial degradation of cell walls and starch, a reduction in the amount of β-glucans, lipids, proteins, and pentosans, and the weakening of the grain’s cohesive structure (the malt becomes brittle).
The malting process consists of three main stages:
1) steeping, during which the grains should absorb as much water as is necessary for further growth, while being provided with an adequate amount of oxygen and with excess carbon dioxide removed;
2) germination, during which enzymes are released and changes occur in the structure of the grain;
3) drying, during which the changes taking place in the grain are halted and compounds responsible for flavor and aroma are formed, while most of the enzymes are preserved.
Thus, in short, malting is the transformation of grain into malt. After steeping, the grain germinates, its structure changes, and enzymes and aromas are released, after which these changes are halted during drying. The task of maltsters is to supervise this process, as mistakes made during malting may result in the rejection of the entire batch of malt.
In theory, it is possible to brew beer exclusively from unmalted raw materials. However, this would be inefficient and relatively difficult without the use of additional enzymes. Therefore, the simple and relatively inexpensive malting process has been used in an almost unchanged form for hundreds of years. Maltsters only refine the details and use grain varieties with increasingly better parameters.