One of the simplest ways to manipulate the flavor of your beer is to use crystal malts. Crystal malts are specialty grains that add flavor and color to any brew. These malts are used in many beer styles, from pale ales to porters, and are the most widely used type of specialty grain. You can use crystal malt no matter what type of homebrewer you are — extract, partial mash or all-grain.
Adding crystal malt is a common way to add a sweet flavor to beer. The sweetness of crystal malt has distinct caramel tones to it. For this reason, crystal malts are sometimes called caramel malts. Crystal malt sweetness is a key characteristic of several styles of beer, most notably in pale ales and related styles. Other sweet styles of beer, such as Scotch ales or milk stouts, employ other methods to achieve their sweetness, including yeast choice and adding sugars that brewer’s yeast cannot ferment.
Crystal malts also add color to your beer. Crystal malts are rated according to their color depth. This is usually expressed in degrees Lovibond (°L). Crystal malts range from 20 °L to around 200 °L and the most common crystals are in the 30 ° to 40 °L range. Pale malts, by comparison, are usually rated between 1.5 ° and 3 °L, while chocolate malts are rated around 350 °L. On the low end of their color range they look only slightly darker than pale malts. As you move up the color range they appear more reddish. The darkest crystal malts are nearly brown. The color of the crystal malt is a function of how it was prepared.
How Crystal Malt is Made
Crystal malts are made from barley grain in a process similar to that of making pale malts. As with pale malts, the grains are steeped and germinated. Unlike pale malts, crystal malts are then stewed — they are heated in a closed system that doesn’t allow moisture to escape. As a result, the starch interiors of the barley grains are broken into sugars by amylase enzymes in the barley. After stewing, the grains are kilned. Kilning dries the grain, darkens the husk and caramelizes some of the sugar inside.
Crystal malt is used in many styles of beer. The amount of crystal malt used varies with the style of beer. Pale ales, bitters or ESBs may contain up to 20 percent crystal malt. For example, a beer may be made with ten pounds of grain, two pounds of which are crystal malt. Lagers such as Octoberfests or Vienna lagers may contain up to 15 percent crystal malt. Darker ales, such as porters and stouts, may also contain crystal malt along with more darkly roasted grains. See the box (at right) for some helpful guidelines to using crystal malt.
The more crystal malt used in a recipe, the darker the color. Since crystal malts are commonly rated in degrees Lovibond, you can calculate how much color you are adding to your beer. To calculate the amount of color contributed by the crystal malt, use the following formula:
HCU = [weight (lb.) x color rating of grain (°L)]/volume of beer (gallons)
HCU stands for homebrew color units. HCU is weakly correlated with SRM. SRM stands for Standard Reference Method, which is the unit preferred by the American Society of Brewing Chemists for measuring the color of malt or beer. (For more on SRM and Lovibond, see “Crystal Malt: Homebrew Science”) For beers that measure from zero to 10, the two color measures — HCU and SRM — are roughly equivalent. For beers over 10 on either scale, the HCU value will be higher than the SRM value. As a rough guide, a dark brown beer with 50 HCUs added would typically have an SRM of 20. Measuring actual SRM requires the use of a spectrophotometer.
HCUs only measure the amount of grain color added to your beer. But many things that affect beer color do not enter into the HCU equation. For example, extended boil times darken the wort. Oxidizing hot wort will also darken it. In contrast, fermentation decreases wort color. Also, different mash or steeping conditions will extract different amounts of color from the grain.
Another limitation of HCUs is that they only measure the amount of color, not the hue. So calculating HCU does not tell you everything you might want to know about color. However, HCU is useful as a relative measure of color among your own beers. If you use the same equipment and brewing procedures the other variables should cancel out and beers with higher HCUs will be darker than beers with lower HCUs.
Using Crystal Malt
The first step in using crystal malt is to crush the grains. If you don’t have a grain mill, have your homebrew shop do it for you. If you do have a mill, the simplest way is to crush the crystal malt along with any other grains you are using. Be aware that the kernel size of crystal malt may be smaller than that of pale malt. If it isn’t getting crushed sufficiently, crush it separately. Your goal is to break the grain into pieces, not grind it into flour.
Extract brewers can steep the crystal malt in their brewing water. To do this they should place the crushed grains in a nylon grain bag and heat their brewing water to between 150–160 °F (66–71°C). The grain bag can then be steeped for 15 minutes. It’s a good idea to stir the water every five minutes or so to move color and sweetness out of the bag and into the brewing water.
Once the 15 minutes of steeping are up, lift the grain bag out of the pot with a large kitchen strainer. Hot water from the pot can be poured into the grain bag to rinse out the (slightly) higher concentration of sugar and color from the grains. If you really want to extract all you can from the grains, rinse the grain bag with 170 °F (77 °C) water. One quart of hot water should suffice for this. Once the grains are rinsed the bag can be set aside and brewing can proceed as normal.
Homebrewers use different variations of the steeping procedure. For example, some prefer to steep their specialty grains in hot wort rather than hot water. These brewers claim that steeping crystal malt in wort extracts less color and flavor than steeping in water but that the flavor is smoother and less astringent when the specialty grains are steeped in wort. To my knowledge, no data has ever been presented to support this view.
Likewise, different homebrewers use different rinsing techniques. Some homebrewers prefer to rinse their grains with cold water instead of water at 170 °F (77 °C). They claim this cuts down on the amount of starch extracted from the grains. If you are using more than a pound of crystal malt, or have had problems with cloudy beer, you might try this. Some homebrewers skip the rinsing step altogether. If you swirl the bag around a few times in the water before removing it, most of the color and sweetness will be extracted. Adding a little bit (perhaps 5 percent) more crystal malt may compensate for a lack of rinsing.
Adding crystal malt to a partial mash or all-grain brew is even simpler than it is with extract beers. Just mash the crystal malt along with the rest of your malt and brew as normal. When mashing, enzymes from the pale malt should degrade any starch from the crystal malts, so worrying about extracting starch is not a problem. Incorporating crystal malt in your beer recipes is a simple way to add color and flavor to your brews.