Homebrew: 1. Maischen

The first step consists of extracting the wort out of the malt. This is done under controlled temperature setpoints and defined resting times.

To control the temperature I have bought an inexpensive PID controller + solid state array and hooked it up to a hotplate (bridging the internal knob).

Four temperatures are important to hold for a certain period of time for the conversion process:

  1. 47-53°C: „Eiweißrast“ – protein gets broken up by special enzymes. Today, this step is not always necessary since in processed malts very little protein is left to begin with. And a little amount of protein is needed for good foam on the final beer!
  2. 62-65°C: „Maltoserast“ – beta-amylase enzymes get re-activated at this temperature and begin converting starch to maltose (sugar). Later on, the yeast converts this sugar to ethanol.
  3. 70-73°C: „Verzuckerungsrast“ – alpha-amylase enzymes get re-activated at this temperature and being converting starch to dextrin. The yeast can only marginally process dextrin. Dextrin leads to a sweet and full-bodied taste in the final beer.
  4. 76-78°C: „Abmaischen“ – force remaining alpha-amylase to get re-activated to convert the remainder of the starch to dextrin. Having any starch left in the wort is highly undesired since this will lead to a fatty and unpleasant taste in the final beer.

A longer Maltoserast means more maltose and therefore ethanol gets produced, leading to a stronger beer. On the other hand, a shorter Maltoserast means more starch is left for dextrin production which leads to a fuller taste. In conclusion, temperature control and timing is crucial for achieving the correct balance between maltose and dextrin, which determine the final strength and taste of the beer.


Homebrew: An introduction to beer brewing

I got into beer brewing after receiving my first starter kit. Beer has a long tradition in Germany and hence the brewing process is very well understood both empirically and technically. In this post I’m going to give you a general introduction to the ingredients and process of brewing your own beer.

For brewing beer four ingredients are required:

  1. Malt: grains that have been germinated and temperature treated (germination produces enzymes which at the end get deactivated by hot temperature)
  2. Water: quality and mineral composition of the brewing water has impact on the taste (since beer consists mainly of water)
  3. Hops: plant belonging to the Cannabaceae family (the other member being Cannabis), brings the unique and bitter flavor to the beer
  4. Yeast: microorganism belonging to the Fungus kingdom, responsible for the fermentation process that converts carbohydrates / sugar to ethanol

And just like that, the brewing process can be divided into four main steps:

  1. „Maischen“: Add malt to water under a controlled temperature curve with defined resting times
  2. „Läutern“: Filter out residual malt particles, the so called draff („Treber“), from the raw yield and so called wort („Würze“)
  3. „Würzekochen“: Boil the wort and add the hop
  4. „Anstellen“: Add yeast to the wort to start the fermentation process

(Some intermediate and finish steps have been omitted, but will be explained later).