Homebrewing

Beer was brewed domestically for thousands of years before its commercial production although its legality has varied according to local regulation.

Beer has been brewed domestically throughout its 7,000-year history, beginning in the Neolithic period in Mesopotamia (modern Iraq), Egypt and China.

Women brewers dominated alcohol production on every occupied continent[1][2] until commercialization and industrialization of brewing occurred.

By the Tang dynasty, homebrewing seems to have been a familiar domestic chore in China, albeit the lower classes had to make do with poorly-filtered mash.

In 1857, French microbiologist Louis Pasteur explained the role of yeast in beer fermentation, allowing brewers to develop strains of yeast with desirable properties such as efficiency converting sugar to alcohol and ability to handle higher alcohol content.

[6] Australia followed suit in 1972 when Gough Whitlam repealed the law prohibiting the brewing of all but the weakest beers in one of his first acts as Prime Minister.

In 1978, President Jimmy Carter signed into law a bill allowing home beers, which had not been permitted unless the excise taxes were paid as a holdover from the prohibition of alcoholic beverages, which had been repealed in 1933.

[citation needed] Owning or operating a distillation apparatus without filing the proper paperwork and paying the taxes carries federal criminal penalties.

For brewers with equipment and advanced knowledge about the brewing process, all-grain kits include all the ingredients necessary to create homebrew beer.

Pre-hopped kits simplify the brewing process by removing the need to add hops at specific times during the boil.

Some kits may not require a boil at all, but that may increase the risk of off flavors in the resulting beer from contamination from bacteria and wild yeasts.

In one procedure popular with homebrewers called the "Infusion Mash", milled grains are combined in the tun and hot water is added.

The sparging process will also stop any further enzymatic activity if much hotter water is used; conversely the mash may be heated to around 80 °C (176 °F) to end such activity prior to placing it in the lauter-tun, and to prevent cooler grain from lowering the sparge water temperature to a lower than desirable figure.

Finings such as Irish moss, a form of seaweed, gelatin, and others can be added in the final 15–30 minutes of the boil to help prevent haze in the resulting beer.

Other benefits of rapidly cooling of the wort include "locking in" hop flavor and aroma, aiding in the production of "cold break" where haze-producing proteins coagulate ultimately resulting in a clearer beer, slowing the production of dimethyl sulfide (DMS), and hindering the growth of wort contamination by pitching yeast as soon as possible.

After placing the cap or the lid, the fermenter is tumbled slightly to let the hot wort sanitise all internal surfaces.

Where the desired outcome is to capture wild yeast from the air, some homebrewers leave the wort to cool in a broad, uncovered container, typically called a coolship.

Recent innovations in nanotechnology have enabled a fermentation lock called the Sterilock to also prevent bacteria, wild yeasts and other potential harmful fungi reaching the fermenter although in some beer styles known as Sour Beer, bacteria or wild yeasts are desirable to obtain the sour characteristics.

A layer of sediment, the lees or "trub", appears at the bottom of the fermenter, composed of heavy fats, proteins and inactive yeast.

While not required, it is generally practiced by home brewers who wish to age or clarify their beer by removing it from the sediment left behind by primary fermentation, often through the addition of isinglass, colloidal silicon dioxide, or spakolloid.

[68] Homebrewed beers and lagers are typically unfiltered[69] (filtering improves visual appearance of the product, but complicates carbonation).

Beer may also be force-carbonated using a keg and special bottling equipment so that the carbonation level can be carefully controlled.

Carbonation is often achieved with approximately 4 ounces (110 g) of corn sugar boiled in 2 cups (500 mL) of water then cooled and added to a typical 5-US-gallon (19 L) batch before bottling.

Carbon dioxide is added to pressurize the keg via an inlet port on the top and is facilitated by gently rocking the brew back and forth.

The kegs are drilled for a drain at the bottom, and the top cut open to create a large stainless steel cooking kettle.

[citation needed] Conventional 15.5-US-gallon (59 L) kegs have circle spring clips that can be removed to release the tap valve.

A simple valve seal depressing tool and a screwdriver with a 1⁄8 inch (3.2 mm) diameter shaft must be used to release the safety catch.

[76][77] Brewers now have access to a variety of software tools, whether free/open source or commercial, which allow them to formulate and adjust recipes.

More traditional Internet forums continue to provide brewers with sources of advice and information from their peers all over the world.

These competitions provide blind feed back to brewers so they can get objective feedback, make adjustments to improve their brewing, and be recognized for outstanding homebrew.