In Part I & II of the Beer Brewing Process, we discussed the first three stages of the five-stage process. These stages are used for the actual production of the beer and include malting, mashing and fermentation. The produced beer must be matured to fully develop its taste and to have the remaining yeast removed from it.
Stage 4 & 5 : Maturation and Filtering
Even though maturing and filtering are two separate tasks, they are most frequently done in a single step. The filtration process involves removing any unnecessary contents from the beer that make it cloudy. Filtration usually takes place during the maturation process.
In the past, the beer was cooled at very low temperatures for extended periods of time in order to remove yeast and other residing chemicals. Now, modern filter technology can remove yeast and other cloudy molecules quickly and effectively. The maturation processed has been shortened from about three months to under a month.
Freshly brewed beer often has a hint of sulphur to its taste because of the presence of H2S, which escapes the beer as a gas and can be vented from the beer. Beer is packaged in aluminium cans or dark containers to avoid the UV rays from light initiating further chemical reactions after brewing.
The modern day production of beer is highly complicated and can only be accurately described by science. The most common present beer brewing is done in large breweries by chemical engineers, but many smaller breweries still employ brewmasters – which are not trained engineers. But beer was discovered by accident and brewed long before the science behind it was understood. Brewmasters use a lot of the same equipment and skills that chemical engineers do. The practice of brewing has evolved from a routine trial and error method to a much more precise process thanks to chemical engineers and brewers alike.
Variations on each of these five stages and the main ingredients of the beer brewing process are applied to produce most of the beers on the market today – whether they be commercial or home brewed.