Brewing

Brewing

IngredientsWater – Must be well-filtered, and have the appropriate levels of calcium and other ions. pH must be carefully watched, as too much acid or base could ruin the final product.

Malt – Made from barley. The barley grains are allowed to sprout, then are kiln-dried to arrest further growth. The barley is rolled between carefully-calibrated rollers to crack the husk of the barley, but not grind it into flour.

Hops – A flower of the plant Humulus lupulus, it is use to stabilize and flavour the final product.

Yeast – Used to ferment the final product, and consume some of the sugars from the malt, which it converts to ethyl alcohol.

Hops

Barley Field

Barley Grains

H-Two-Woah

Yeast (budding)

Yeast (budding)

ProcessMashing – The malt is added to the water, and it mashed in a temperature-controlled vat. A large blade turns the mash. At this stage, other ingredients may be added for flavour, such as wheat, rice, corn, etc.

Lautering – The mash is filtered, to remove the big chunks of malt and grain. The filtrate (liquid that comes out) is called wort. Water is sprayed through leftover grains to remove as much wort as possible.

Boiling and hopping – The wort is boiled at a very specific temperature for a very specific period of time, depending on the desired outcome. The wort is boiled for about two hours, and hops are added at this stage. The boiling serves to extract flavors, sterilize, and achieve a desired specific gravity. Hops are strained out after this step. Unwanted precipitates are removed here, as well.

Cooling – The wort is cooled to about 15.5 degrees C.

Fermentation – Yeast is added. Top-fermenting yeast is used in ales and stouts, while bottom-fermenting yeast is used for lagers.

Some brew houses use natural yeast. They simply open the doors, and let yeast come in. Most modern breweries use a specific species of the genus saccharomyces. The yeast breaks down the sugars in the wort, making ethyl alcohol and carbon dioxide.

Process

Mash Tank

Mash

Lautering

Lautering

Boiling

Fermenting

Pasturization

Louis Pasteur

Specific Gravity

Relating the weight of something to the weight of an equal volume of something else, usually water.

We can use a hydrometer to measure this.