Water, starch, hops and yeast

In case you didn’t know, there are only four fundamental ingredients in beer: water, starch, hops and yeast. That’s it. Other ingredients are sometimes used (often as additional flavoring agents), but at the basic level, beer only has four components.

Cool, clear, water

The first and most simple of the four is water. I know you’re thinking that it seems pretty straight forward, but subtle variations in water’s chemical composition play a huge part in determining the final product. Different regions have water with different mineral components; as a result, different regions were originally better suited to making certain types of beer. For example, Dublin has hard water well suited to making stout, such as Guinness; while the Pilsen region in the Czech Republic has soft water well suited to making pale lager, such as Pilsner Urquell. The waters of Burton in England contain gypsum, which benefits making pale ale to such a degree that brewers of pale ales will add gypsum to the local water in a process known as Burtonisation.

Delicious malted barley

The next ingredient is the starch, which provides the fermentable material and is a key determinant of the strength and flavor of the beer. The most common starch source used in beer is malted grain. Grain is malted by soaking it in water (allowing it to begin germination) and then drying the partially germinated grain in a kiln. Malting grain produces enzymes that convert starches in the grain into fermentable sugars. Different roasting times and temperatures are used to produce different colors of malt from the same grain, with darker malts producing darker beers.

Nearly all beer includes barley malt as the majority of the starch due to its fibrous husk, which is important in the sparging stage of brewing (water is washed over the mashed grains to form the wort) and also because it is a rich source of amylase, a digestive enzyme that facilitates starch converting into sugars. Other malted and unmalted grains (including wheat, rice, oats, and rye) may be used. In recent years, a few brewers have produced gluten-free beer made with sorghum instead of barley malt for people that cannot digest gluten-containing grains like wheat, barley, and rye. Big brewers like InBev/AB and Miller Coors use corn as an inexpensive replacement for barley, but needless to say, that is NOT an acceptable practice.

Sweet smelling hops

Flavoring beer is the work of hops. The flower of the hop vine is used as a flavoring and preservative agent in nearly all beer made today.

Hops were used by monastery breweries, such as Corvey in Westphalia, Germany, from 822 AD, though the date normally given for widespread cultivation of hops for use in beer is the thirteenth century. During this time, beer was flavored with other plants and various aromatic herbs, berries, and even ingredients like wormwood, which were combined into a mixture known as gruit and used as hops are used today. Hops remained a fringe flavoring agent until the sixteenth century when taxation of traditional gruit ingredients by the church forced brewers to accept using the bitter flower.

Hops contain several characteristics that brewers desire in beer. They contribute a bitterness (which is measured on the International Bitterness Units scale) that balances the sweetness of the malt. Hops also contribute floral, citrus, and herbal aromas and flavors to beer. Additionally, they have an antibiotic effect that favors the activity of brewer's yeast over less desirable microorganisms, and hops aids in "head retention", or the length of time that a foamy head created by carbonation will last. Finally, the acidity of hops is a preservative, which in the old days was a very big deal, though not as important today.

The little buggers hard at work

The fourth and final ingredient is yeast, a microorganism that is responsible for fermentation in beer. Yeast metabolizes the sugars extracted from grains, which produces alcohol and carbon dioxide, and thereby turns wort into beer. In addition to fermenting the beer, yeast influences the character and flavor. The dominant types of yeast used to make beer are ale yeast and lager yeast (see my blog post on zymurgy for more info). Before the role of yeast in fermentation was understood, fermentation involved wild or airborne yeasts. A few styles such as lambics rely on this method today, but most modern fermentation adds pure yeast cultures.

Here’s to craft-brewed happiness… Cheers!