Understanding Grains & Malting

What would we do without grains? We certainly would not be able to make beer. Grains not only create the sugars used by yeast for fermentation, they also provide the majority of the flavor, color, and body in our favorite beverage.

When grains are being classified, only the highest quality grain can be considered brewing grade. They are selected based on the uniformity of the size of the kernel, high starch levels, high diastatic power, and low nitrogen content. Although Barley is the most popular, many other types of grain may be used in brewing such as wheat, corn and rye.

So let’s take a look at the basics of brewing grains:

2-Row vs 6-Row

There are two types of barley used in brewing, and each gets their name from the way in which the barley grows on the stalk. 2-row barley has 2 rows of seeds on each of the stalk heads and 6-row has six rows of seeds on the head of the stalk. But what are the real differences? 2-row seeds are traditionally plumper as they are less crowded when growing. Because of this, they also have thinner husks which means that they have fewer proteins. They also tend to have a smoother and cleaner flavor profile as compared to 6-row base malts.

6-Row barley has developed a reputation for not being as tasty as 2-row. It is true that 6-row is a bit grainier than its predecessor, but this is not very noticeable in most beers, especially those that use a large amount of specialty grains and/or hops. So why use 6-row base malt? It has a much higher amount of enzymes or diastatic power. This makes 6-row especially useful when making a recipe that utilizes a lot of adjuncts or specialty grains with little to no diastatic power. We will go into further detail about enzymes in a little bit.

Malting Process

Malt is the end product after barley is processed by a Maltster via a three-step process. During which they take cereal barley and steep the grains in water for a period of two to three days to increase the moisture content of the grain to approximately 46-50%. At this time, the embryo inside of the grain kernel begins to germinate.

The Maltsters will then move the grain into a germination vessel. While in the vessel, humidified air is blown through the grains at a specified temperature to keep the grain from drying out and to promote the germination process. The grain will be periodically turned to keep the grain loose. This will occur over a period of four to six days depending on the malt type. Once sufficient enzymes have been produced within the grains, the cellular walls of the starches will begin to breakdown (known as modification).

Once this modification has occurred, the Maltster will move the grains to a kiln to stop the process by applying heat at 120°-160°. They will continue drying the malt for about two to three days until it reaches a moisture level of approximately 3-6%. At this time, the grain has become a base malt.

After the drying process has been completed, specialty grains will continue to be kilned at higher temperatures and for longer periods of time. This is where the true art of the Maltster comes into play. Additional kilning is what gives the grains the different flavors and colors that we use in our beer. By adjusting the time and temperature, they can determine the look and flavor profile of the grain; from light toast and caramel flavors to dark roast and chocolate.

Malted Grains

Base Malts- Base malts provide the largest amount of sugars and diastatic power of all of the grains and make up the largest portion of a brewing grain bill. They have been kilned at low temperatures so that they will retain a large portion of starches and enzymes.
Examples: Standard 2-Row, Standard 6-Row, Pale Malt, Pilsner Malt, Munich Malt, Vienna Malt

Crystal/Caramel Malts- Crystal and Caramel are different names for the same malt. Crystal malts do not go through the drying process and are instead moved to a roaster after they are germinated. In the roaster, the starches within the grain are converted to sugars. This is very similar to the process that brewers use when mashing. After the starches are converted, the temperature is increased to create the color and flavor. Some of the sugars in crystal malts caramelize during kilning and become unfermentable and will increase the final sweetness of a beer.
Examples: Crystal 10°-120°L, Carapils, Special B, Caramunich, Carastan.

Toasted Malts- Toasted malts are completely dried and then kilned at high temperatures in order to increase their color and cause less caramelization. This gives the grains flavors of nuttiness and toast.
Examples: Victory Malt, Brown Malt, Amber Malt, Aromatic Malt

Roasted Malts- Roasted grains are kilned at low temperatures with very low moisture. The temperature is then slowly increased to high temperatures over 400°. To keep the grains from burning, they are continually sprayed lightly with water. Roasted malts are the darkest of all of the malted grains. They also provide very strong flavors such as chocolate and coffee. Roasted malts are usually used in very small quantities.
Examples: Black Patent Malt, Blackprinz, Chocolate Malt, Carafa Malt

Unmalted Grains- In addition to all of the malted grains available, there are also unmalted grains that can be utilized by the brewer. They are often referred to as adjuncts and are used for such purposes as increasing or lightening the body and color of a beer, increasing head retention and adding additional flavors. Unmalted grains usually come in two varieties, raw and flaked. In order to use raw grains, the brewer will need to do a cereal mash. This is done by boiling the raw grain with some of the malted grains. This will cause the raw grains to begin to gelatinize. Flaked grains have already been gelatinized and are then rolled out, so no processing is necessary.
Examples: Corn, Wheat, Barley, Rye, Oats, Rice

Malt Color

The scale used for measuring malt color is called Lovibond or Degrees Lovibond. This is usually abbreviated using the symbol °L. The degree of lovibond assigned to a grain is based on wort that is created in a lab. The varying color can range from as low as 1° for a very light base malt, to as high as 500 °L. Although lovibond is used solely as a way of determining malt color, it is also important to mention that the flavor is always a factor as well.

Enzymes and Diastatic Power

Throughout this article we have mentioned how enzymes are present in malts, but what are they? The definition of an enzyme is “A substance produced by a living organism that acts as a catalyst to bring about a specific biochemical reaction.” In the case of brewing, the biochemical reaction is from the Beta and Alpha Amylase Enzymes that are created during the malting process. These enzymes break down the long starch molecules into much shorter chains of sugar, mostly maltose as well as some un-fermentable sugars giving us wort.

Another term that is often used when referring to grain is diastatic power. Diastatic power refers to the enzymatic power of the malt. The malts ability to break down starches into simpler fermentable sugars during the mashing process. As an example, 6-Row base malt has a higher diastatic power than 2-Row base malt.

The scale that is used to determine the diastatic power of a grain is Lintner. Now, just to make things really confusing for everyone, the symbol that is used to denote Lintner is °L. Yes, this is the same symbol that we use for Lovibond. So it is very important to make sure that you are reading malt diagrams correctly so that you do not confuse the two.

As grains are responsible for so much of the character of our beers, the more we learn about these ingredients, the more options we have in developing different flavor profiles and making truly outstanding beer.

For more information on brewing grains, please reach out to the staff of The Brew Hut, who will be happy to show you our large grain selection of over 80 different varieties of brewing grains.

Cheers!