Take a moment to better understand the steps for our tasty brews to reach perfection. We're certain to follow through with our guarantee to manufacture the highest quality beer we can offer.
1. MILLING AND MALTING
Milling is the cracking of the grain which the brewer chooses for the particular batch of beer. Milling the grain allows it to absorb the water it will eventually be mixed with in order for the water to extract sugars from the malt. Then in malting, the first ingredient to come into play is barley, which is grain (or, in other words, a seed). The seeds are soaked in water for about two days and allowed to begin their development into plants. Enzymes are released that break down the proteins and starches in each grain into simple sugars meant to nourish the baby plant. However, once this process has begun, the barley is cooked in a kiln, arresting the growth process while the enzymes are at their peak of production. This is called malting.
In the mashing stage, the grain is actually transformed into sugar. The grains are crushed into a fine powder, or grist, and then soaked in water. Proteins are broken down; these eventually give the beer its body. Starches are broken down into simple sugars that nourish the yeast. Complex sugars remain to give the beer its malty taste. The mash is heated and strained to yield a substance called wort. Next, the wort is brought to a boil and the flowers of the female hop plant are added. Bitter resins and aromatic hop oils are released. The variety of hop, the amount added, and the point or points in the boil at which they are added all contribute to the flavor of the beer. They add bitterness when added early to the boil, flavor if added in the middle, and aroma when added at the end.
The mash is transferred to a straining or “lautering” vessel, usually cylindrical, with a slotted false bottom two to five cm above the true bottom. The liquid extract drains through the false bottom and is run off to the brew kettle. This extract, a sugar solution called “wort”, is not yet beer. Water is “sparged” or sprayed through the grains to wash out as much of the extract as possible. The “spent grains” are removed and sold for cattle feed.
Boiling the malt extracts, called wort, ensures its sterility, and thus prevents a lot of infections. During the boil hops are added, which contribute bitterness, flavour, and aroma compounds to the beer, and, along with the heat of the boil, causes proteins in the wort to coagulate and the pH of the wort to fall. Finally, the vapours produced during the boil volatilise off flavours, including dimethyl sulfide precursors. The boil must be conducted so that it is even and intense. The boil lasts between 50 and 120 minutes, depending on its intensity, the hop addition schedule, and volume of water the brewer expects to evaporate.
At the end of the boil, the wort is set into a whirlpool. The so-called teacup effect forces the denser solids (coagulated proteins, vegetable matter from hops) into a cone in the center of the whirlpool tank. In most large breweries, there is a separate tank for whirlpooling. These tanks have a large diameter to encourage settling, a flat bottom, a tangential inlet near the bottom of the whirlpool, and an outlet on the bottom near the outer edge of the whirlpool. A whirlpool should have no internal protrusions that might slow down the rotation of the liquid. The bottom of the whirlpool is often slightly sloped towards the outlet. Newer whirlpools often have “Denk rings” suspended in the middle of the whirlpool. These rings are aligned horizontally and have about 75% of the diameter of the whirlpool. The Denk rings prevent the formation of secondary eddies in the whirlpool, encouraging the formation of a cohesive trub cone in the middle of the whirlpool. Smaller breweries often use the brewkettle as a whirlpool.
After the whirlpool, the wort must be brought down to fermentation temperatures (20-26°Celsius) before yeast is added. In modern breweries this is achieved through a plate heat exchanger. A plate heat exchanger has many ridged plates, which form two separate paths. The wort is pumped into the heat exchanger, and goes through every other gap between the plates. The cooling medium, usually water, goes through the other gaps. The ridges in the plates ensure turbulent flow. A good heat exchanger can drop 95 °C wort to 20 °C while warming the cooling medium from about 10 °C to 80 °C. The last few plates often use a cooling medium which can be cooled to below the freezing point, which allows a finer control over the wort-out temperature, and also enables cooling to around 10 °C. After cooling, oxygen is often dissolved into the wort to revitalize the yeast and aid its reproduction.
The wort is then cooled and moved into a fermentation vessel. Yeast is added and allowed to consume most or all of the sugars in the wort. This is the fermentation process during which alcohol is produced. The process takes about ten days. Each brewery has its own strains of yeast, and it is the yeast that determines the character of the beer.
8. STORAGE AND MATURATION
The beer is then separated from the yeast (racked). Once the yeast is removed the beer is passed from fermentation to storage vessels. During transfer the beer is cooled to minus one degree centigrade. The beer stays in storage at this temperature, and any material which might impair the appearance, flavour and shelf-life of the beer settles out.
Following a set time in storage, carbon dioxide gas collected during fermentation is added to give beer its characteristic head and sparkling taste. The beer is then passed through a filtration system to remove surplus yeast and protein.
Pasteurisation is a process of heating and rapid cooling which prolongs shelf-life and destroys any bacteria or other organisms in the beer. Canned and bottled beers are pasteurised in their containers, while draught beer is pasteurised by means of a special heat exchanger called a flash pasteuriser.
The filtered and sparkling beer is packaged into bottles, cans and stainless steel casks, or kegs, ready for distribution.