Beer can be made using just barley as the main grain. In fact, barley is the most commonly used grain in beer production and forms the base malt for all types of beers around the world. It provides the essential sugars that yeast ferment into alcohol, giving beer its characteristic flavor and body.
When brewing with barley, it is important to use malted barley. Malting is the process of soaking barley in water, allowing it to germinate, and then drying it in a kiln. This activates enzymes in the barley that convert its starches into fermentable sugars. These malted barley grains, known as malt, are then crushed and mixed with hot water in a process called mashing, which further breaks down the starches into sugars.
The resulting liquid, known as wort, is then boiled and hops are added for bitterness, flavor, and aroma. Hops also act as a natural preservative in beer. After boiling, the wort is cooled and yeast is added to begin fermentation. The yeast consumes the sugars in the wort and produces alcohol and carbon dioxide.
While barley is the backbone of beer, other grains can also be added as adjuncts to enhance flavors and add complexity. Adjunct grains such as oats, rye, wheat, and corn can be used, but they should only make up a smaller portion, typically up to 30%, of the total grain bill. These adjuncts can contribute different flavors, textures, and mouthfeel to the final beer.
Using just barley in beer production allows for a wide range of styles and variations. Different types of barley, such as pale malt, roasted malt, and caramel malt, can be used to create beers with varying colors, flavors, and aromas. For example, a beer made primarily with pale malt will result in a lighter, crisper beer, while the addition of roasted malt can create a darker, richer beer with flavors of chocolate or coffee.
Personally, I have brewed many beers using only barley as the main grain and have been impressed with the results. The simplicity and versatility of barley allow for a wide range of beer styles to be created, from light and refreshing lagers to robust and complex stouts.
While other grains can be added as adjuncts, it is absolutely possible to make beer with just barley. Its unique characteristics and ability to convert starches into fermentable sugars make it an essential ingredient in beer production. So, whether you're a fan of traditional beer styles or looking to experiment with your own recipes, barley is the foundation upon which great beers are built.