Hops and m alt - God preserves
The brewer only needs four things: m alt, water, hops and yeast. But the road to beer is long.
In 1516, the Bavarian Duke Wilhelm IV put an end to some obscure brewing practices and established the "German Purity Law". Since then, beer in this country can only be made from the basic ingredients barley, hops and water. And of course with the help of yeast, which was already responsible for fermentation back then, but nobody knew about its existence: it was not added, but was omnipresent in the air in the fermenting room.
Before barley can be made into beer, it has to be m alted. To do this, the grain is soaked in water and allowed to germinate. In the next few days, enzymes are produced that are later to convert starch into sugar - in nature, the germinating plant feeds on this. But before these molecules become active, the "green m alt" is dried in the kiln, where germination is stopped. Depending on how long and how hot the air blows over the grains, light to dark m alt is produced, later lighter or darker beer accordingly.
In the brewery, the m alt is crushed, mixed with water in the mashing pan and gradually heated. At certain temperatures – the one or two-hour rest period – the enzymes mentioned get going and the mash gradually becomes sweeter. In addition to the saccharification, a variety of other biochemical reactions are also taking place, producing important nutrients for the yeast - as well as substances that will ensure a nice foam.
Once the starch molecules have been completely converted into sugar, the mash is transferred to the lauter tun. The insoluble m alt components remain on a filter floor. These spent grains are valuable cattle fodder.
Did you know?
The name Bockbier probably derives from the northern German town of Einbeck, where beer has been brewed since the 14th century. In Bavaria it was first called "AinpöckischesBier", then "Ainpockbier" and finally "Oanbock". The wort obtained in this way then flows into the brewing pan, where it is boiled and hops (Humulus lupulus) are added. Hops were first mentioned in a text from 768. For a long time it was used solely to preserve beer. Because its bitter substances inhibit lactic acid bacteria, which were the beer's greatest enemy before pasteurization. Today there are dozens of hop varieties with different levels of bitterness, and it is entirely up to the master brewer to add which hops to the wort and when to achieve the desired taste.
Before the invention of the chiller, one last beer was brewed in the spring. This was stronger so it lasted longer and the beer-free summer break was as short as possible. The beer was named Maerzen after the month it was brewed.
Apparently a Kulmbach journeyman brewer froze a beer keg in the yard one winter a hundred years ago. But only the water was frozen, while the concentrated beer remained liquid. Since then there has been the Eisbock with an alcohol content of nine percent. And by the way: The first beer can was filled in 1935 at the Krüger Brewery in Newark, New Jersey.
The work of the added yeast then begins in the cold store. Before the invention of the refrigeration machine in 1873 by Carl von Linde, almost only "top-fermented" beers were brewed. This is because the yeast species Saccharomyces cerevisiae feels particularly at home when the temperature does not fall below 15 degrees Celsius. And it tends to accumulate on the surface of the wort after the work is done, hence the name. Alt beers, wheat beers and Kölsch are among the best-known top-fermented types.
Did you know?
The German beer drinker is in third place in an international comparison. He consumes over 120 liters per year. A good 150 liters flow through the Irish throats, the Czechs even bring it to around 160 liters. The bottom-fermented Saccharomyces carlsbergensis, on the other hand, requires temperatures below ten degrees Celsius and settles at the bottom of the vessel after fermentation. In the past, such beers could only be brewed in winter. Today, the vast majority of beer in this country – including Pils, Export and Märzen – is brewed bottom-fermented.
The yeast first uses the oxygen in the wort for aerobic growth and after a few hours switches to anaerobic metabolism, the actual fermentation. Only now does she convert sugar into alcohol. This also produces carbon dioxide and heat, but also substances that cause the "fat head" the next morning.
Did you know?
Altbier is not old, but simply fermented in an "old" way, i.e. top-fermented. In the case of top-fermented beer, fermentation is already complete after two to three days. Bottom-fermented beers, on the other hand, have to be stored for several weeks before being filtered and finally bottled under pressure.
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