Soft fire makes sweet malt

Malt is one of the most important raw materials for beer. To produce malt, the kernels of grain are germinated. Follow the brewing barley on its way to becoming malt.

Before the brewer comes the malster. Top quality beer would not be possible without the malster’s trained eye and experience. The malster selects the barley varieties that, through multiple steps of germination and drying – or “kilning” according to the specialist – are ultimately turned into malt. It is crucial for the quality of the beer. That is why the Andechs Monastery brewery procures its malt exclusively from Bavarian malthouses.

Aside from the barley, the beer only contains hops and yeast. However, these raw materials pose a major challenge for the master brewer: They are natural products and, as such, their characteristics and quality are naturally altered from year to year. Ultimately, the art of brewing beer lies in taking the varying composition of the hops, malt, water and yeast into account to brew a beer that meets the highest quality standards and has a consistent taste.

What brewing barley needs to grow

The malt as a raw material for beer production is made from brewing barley. Barley adapts to the respective environmental conditions relatively easily and also ripens quite quickly. It can be cultivated on all continents as a raw material for beer production – from Europe’s maritime latitudes to the dry climate of the African continent.
Barley thrives especially well in loamy and loess soils as well as fields that are rich in humus. The soil should not be acidic, meaning the pH value should be slightly in the alkaline range. Farmers add lime to the soil in order to accomplish this as needed. Agricultural operations that include stock farming are also favourable for barley cultivation. Manure mixed with straw and compost supplemented by fertiliser can loosen arable soil and form humus.

Why brewing barley is particularly well suited as a raw material for malt production

Brewing barley is the favourite raw material for beer production due to several ideal prerequisites: It contains substances such as starch and enzymes. In addition, the husks that surrounds the kernels – unlike with wheat and rye – serve as a natural filter layer during lautering in the brewhouse.
Barley comes in two-row and multi-row varieties. Two-row spring barley with its unrestricted kernel formation, however, provides the best conditions for the production of quality beers. Central Europe’s moderate climate along with favourable soil conditions makes this region ideal for the cultivation of brewing barley. A certain crop sequence also needs to be observed for a high crop yield. Root crops such as turnips and potatoes as preceding crops have been shown to contribute to a high brewing barley yield.

Spring barley – from seeding to harvest

In our latitudes, barley is sown from late March to early April. In the growth phase until “heading” (the production of heads of grain clusters), the sowing needs a lot of moisture.
Then the kernels form after heading: Water-soluble substances from the soil travel through the stalk to the head, where starch and protein are formed and stored in the kernel as reserves for the later growth of a seedling (the next generation). At harvest time between late July and early August, these processes should be largely completed and the moisture content should be no more than 15%. Dry and warm weather is therefore needed for kernel formation.
This in turn illustrates that the germination capacity, swelling capacity and water and protein content keep changing depending on weather conditions during seeding, the growth phase and at harvest time.

Raw barley
After the harvest and interim storage, the raw barley is delivered to the malthouse. Before it is unloaded, the master malster checks the protein content, humidity, grading, germination capacity and odour. The raw barley is mechanically cleaned and the awns are removed before malting.
Then the raw barley is immersed in water and left to “soak” for one to two days. The kernels absorb water during this time. They enlarge by almost a third in this process and begin to germinate. Enzymes form during germination. These are proteins that, as catalysts, can trigger and/or speed up chemical and biological processes. For example, these enzymes turn starch into maltose, a type of sugar.

Green malt
To accelerate the germination process, the kernels are then poured onto large gratings or into boxes. Here they germinate, forming sprouts and rootlets. This is now “green malt”. Germination produces heat that must not be allowed to exceed a certain temperature. The green malt is therefore cooled with a flow of cold air. Green malt germination takes a total of four to nine days. Here the malster’s experience is of particular importance. If the kernels are not germinated long enough, the brewer will later obtain an inferior wort in the brewhouse. If they are germinated too long, many of the substances contained in the kernel that are important for the brewing process are transferred to the sprout and thus lost to the brewer.

Kilned malt
The crucial difference
The germination process is halted by “kilning”. In the malthouse, the green malt is transferred to tower-like silos with intermediate floors for this purpose and hot air is blow in at the bottom. This dries the kernels so they lose their moisture and germination capacity. Not least, kilning also determines the colour of the future beer. Light or dark malt is produced depending on the temperature. Light malt needs up to 80 degrees Celsius, dark up to 110 degrees. It is crucial to only increase the temperature gradually, otherwise the water escapes from the kernels too quickly, forming cavities that make the malt brittle. There is good reason for the old malster’s saying: “Soft fire makes sweet malt.” Kilning also produces important flavouring substances such as caramel. These are of decisive importance for the taste of the future beer. While the enzymes do not continue working in the kilned malt, they become active again immediately when they come into contact with water during mashing in the brewhouse.
The kernels are continually turned automatically during malting, causing the rootlets to drop off. The cotyledons are automatically removed as well. They would give the beer an unappealing aftertaste.

At the end of malting, the kernels look almost the same as they did at the start of the process. Except for the colour of dark malt, the crucial difference is not visible to the layperson. But anyone can tell by biting the kernel. Raw barley is hard and does not have a particularly intense flavour. Malt is pleasantly mellow and sweet. That is because the enzymes have turned part of the starch into sugar.

Barley malt and wheat malt
Barley malt includes Pilsner malt, Vienna malt, Munich malt and roasted malt. Certain speciality malts have a stronger caramel flavour and make the beer more full-bodied. Aside from barley malt for bottom-fermented beers, there is also wheat malt for top-fermented beers. Rye and spelt malts are used for special beer creations.

Andechs Monastery Emblem