Water, Starch, Hops, and Yeast

Did you 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.

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 water near Burton in England contains gypsum, which imparts a desired mouth feel into pale ale—so much so that many brewers will add gypsum to the local water when they brew pale ales in a process known as Burtonisation.

The next ingredient is the starch, which provides 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 in the kiln are what produce the different colors of malt, 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 conversion 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. Some big breweries like to use corn as an inexpensive replacement for barley, but needless to say, that is not an acceptable practice.

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 in the same way 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 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. 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 breweries ferment with pure yeast cultures.

That’s it. The foundation of every beer we make, and every beer you drink, is summed up in those four ingredients. Of course, this is just the beginning. Which varieties of hops, grain, and yeast, in what proportion, added at what point in the process, and so on . . . that’s where it gets complicated. But don’t worry; we’ll take care of the hard part for you. All you have to do is enjoy the finished product.

To the Republic (if you can keep it)… Cheers!