Pin It

How do you make beer? 

What follows is only an abbreviated version of the beer-making process, and is not meant as a step-by-step procedure.

Beer is an alcoholic beverage made from malted grains, hops, yeast, and water. The grain is usually barley or wheat, but sometimes corn and rice are used as well. Fruit, herbs, and spices may also be used for special styles. The process consists of: Milling, Mashing, Wort Separation, Boiling, Hop Separation, Cooling, Fermentation, Aging and Packaging.

Milling: The act of crushing malted barley and other grains. The purpose is to break open the outer portion of the grain to expose the inner layers. It is then poured into a "mash tun"- a tub used for sugar extraction.

Mashing: The crushed grain is infused with hot water as it runs into the "mash tun," a process called "doughing in." This mixture is allowed to steep according to a particular temperature profile in order to convert malt starch into fermentable sugar. When starch conversion is complete, the liquid sugar solution, called "wort," must be removed from the spent grain.

Wort Separation: The sweet wort is drained from the grain bed in a process called "lautering." After the strong wort is pumped into the kettle, weaker wort is rinsed out with hot water in a process called "sparging." This weaker wort is also collected in the kettle.

Boiling: The wort is brought to a boil, and measured quantities of hops are added. The brewer adds hops in the beginning of the boil to add bitterness, in the middle for flavoring, and in the end to add aroma to the brew. Fruit, spices or sugar adjuncts (like homey, molasses or invert syrup) may also be added during the boil. This process, typically lasting between one and three hours, has the important effect of sterilizing the wort prior to fermentation.

Hop Separation: After boiling, the hops are no longer needed and must be removed prior to fermentation. The most common method of hop separation is the use of a whirlpool vessel, where the spinning liquid causes pressure differences that force the hops and haze-forming solids to settle out of solution via the "tea-cup effect."

Cooling: The boiled, clarified wort is pumped through a heat exchanger in order to reduce the temperature to the desired level for fermentation. Yeast is the active microorganism responsible for fermentation, and performs best in a temperature range of 46 degrees to 76 degrees Fahrenheit (depending on the strain of yeast used). By cooling the wort rapidly, the yeast can be added as soon as possible to initiate fermentation and protect it from spoilage by other microorganisms.

Fermentation: Brewer's yeast is often added or "pitched" into the wort during transfer to a fermentation vessel. Old, traditional vessels were open to atmosphere (open fermenters), whereas modern vessels are sealed (closed fermenters). Brewer's yeast metabolizes malt sugars into alcohol, carbon dioxide, and flavor components. Production of alcohol and carbon dioxide from "primary" fermentation typically takes between four and nine days.

Aging: After primary fermentation most of the yeast enters a dormant phase while a portion of the yeast remains active. Aging is also known as "cold conditioning" because the near-freezing temperature helps settle the yeast and stabilize the beer clarity. The remaining active yeast plays an important role in flavor maturation. The dormant yeast, traditionally, is removed from solution by natural settling, but modern technology (and money) allows brewers to use centrifugation or filtration to remove yeast from the fermented beer. Aging can last as little as one week or may last several months. Prior to packaging, most beer is filtered to remove any remaining yeast.

Beer carbonation can be achieved using one of three methods: 1) adding a dose of actively fermenting beer to the flat beer in the aging tank, a technique known as "krausening"; 2) injecting carbon dioxide into the filtered beer; or 3) inducing refermentation in the bottle by adding active yeast and fermentable sugar.

Packaging: For much of its history, beer has been packaged in wooden barrels generally called "casks." The British had colorful names for different cask sizes (measured in Imperial Gallons): a Pin -- 4.5 gallons; a Firkin -- nine gallons; a Kilderkin (slang "Kil" or "Kiln") -- 18 gallons; a Half-Hogshead -- 27 gallons; a Barrel -- 36 gallons; and a Hogshead -- 54 gallons. While some specialty beers are still fermented in wooden vessels, almost no beer is now shipped in wooden casks. For the most part, aluminum and stainless steel kegs have replaced casks. The most popular container these days is the glass bottle, followed by the aluminum can. The first beer to be sold in a plastic bottle was brewed by Bass in 1997.

  • Pin It

Comments

Subscribe to this thread:

Add a comment

Latest in Beer Issue

08/28/2014

Search Events

Recent Comments

© 2014 Creative Loafing Atlanta
Powered by Foundation