The beer brewing process
1. Malt Crushing
Firstly, we need to know the purpose of malt crushing, which is to split the wheat husk longitudinally, exposing the endosperm portion of the wheat kernel, which is broken up by crushing, allowing all parts of the endosperm to undergo an enzyme-catalysed decomposition effect that separates the husk from the lees.
According to the requirements of the craft beer process, the standard of malt crushing is: the malt grain skin is broken but not crushed, and the endosperm is crushed as much as possible. During wort filtration, the malt hulls act as a natural filter layer, so the hulls should be kept as intact as possible. If the hulls are crushed too finely, the bad layer will be too tight, increasing the resistance of filtration and prolonging the filtration time; in addition, the harmful substances in the hulls will dissolve more into the wort, deepening the colour of the wort, and making the taste of the beer rough and unpleasant.
The use of malt contains a variety of hydrolytic enzymes, in the appropriate conditions (temperature, PH value, time) of malt and auxiliary materials in the insoluble polymer substances are gradually decomposed into soluble low molecular substances, this decomposition process is called saccharification.
The purpose of saccharification is to make use of various enzymes to dissolve the insoluble substances and obtain as much soluble matter as possible, so that the wort forms a more suitable concentration.
3. Wort Filtration
After the end of saccharification, the saccharification fermentation must be carried out as soon as possible for the solid-liquid separation, that is, filtration, so as to obtain a clear wort. The solid part is called "lees" and the liquid part is wort, which is the substrate for beer yeast fermentation.
The rough husk from grinding the malt becomes the perfect filter at this point and produces a very thick wort, which is the first wort.
Boiling the wort means cooking the wort for 60 to 120 minutes. This causes the substances in the wort to react, evaporating the water and the unfavourable flavours of the beer, and at the same time sterilising the wort. During this time, we add the all-important hops to give the beer its bitterness and aroma. Other special ingredients, if required, are also added at this point.
At the end of the boil, the wort is pumped into a filter swirler for swirling and settling the wort. After boiling, the wort is swirled for 3-5 minutes and left to settle for a period of time, then the hot coagulum is drained off and the wort is cooled. The length of this process also has an effect on wort fermentation.
As yeast can only ferment at low temperatures, the hot wort must be cooled to the required fermentation temperature before it can be inoculated. The use of a plate heat exchanger allows the wort to be cooled quickly to the inoculation temperature of the yeast. A long period of slow cooling increases the chances of harmful microorganisms multiplying in the beer. Therefore, rapid cooling is very important. After the wort has begun to cool, thermal coagulation will continue to settle during the period up to 60°C. The wort will then be cooled to the temperature of 60°C and the yeast will be allowed to settle.
After the wort has been maintained at a suitable temperature, it is ready for fermentation after the yeast has been put in. Under the powerful action of the yeast, the simple sugars are broken down and alcohol, carbon dioxide and lipids (aroma molecules) are produced. After a period of fermentation, the flavour of the beer matures.