Using Specialty Malts
When I began brewing back in 1992, I felt fortunate to find either a packet of dry yeast or a can of malt extract that had not celebrated a birthday, much less to hope to find one of a specific kind. Specialty malts were even more difficult to find. But today we homebrewers live in malt heaven, with suppliers offering varieties of malt numbering in the dozens. I will cover the basic types of specialty malt available and how you can incorporate them.
First a little background. All malt begins as raw grain. The grain is steeped in water, and then allowed to rest until it sprouts and the interior of the kernel begins a transformation that will allow it to convert starch to sugar. At this early stage the grain is referred to as green malt. The maltster can then take the green malt down a myriad of paths to produce anything from standard pale base malt to dark crystal malt and everything inbetween. Most specialty malts are made from barley, but malt made from wheat and rye are also major ingredients in many beers.
Green malt is then processed further to produce malt that you will have to mash to complete the conversion to sugar, or malt that will already be converted to sugar without the need for mashing. Most green malt takes the former route and is carefully dried, then kilned (gently roasted) into a malt with a healthy complement of amylase enzymes giving the malt its diastatic power. This diastatic power allows this malt to convert itself from starch to sugar when mashed. Examples of these malts include pale, Vienna, and Munich malt made from barley, along with standard wheat and rye malt. Alternatively, green malt can be carefully stewed in its own juices rather than dried so the enzymes complete conversion of starch to sugar (saccharification) within the kernel to produce crystal malts such as caramel and cara-pils.
Both pale and caramel or crystal malts can then be roasted at higher temperatures to produce many different final products. This additional roasting caramelizes the malt via the Maillard reaction; where free amino nitrogen and sugars combine to produce all those roasty-toasty flavors we love. To add to this malted and roasted diversity, there are also many varieties of barley, wheat, and rye. Roasting reduces any malt’s diastatic power, so malt that is roasted to a dark color may not be able to convert starch to sugar in a mash.
Now that you know some of the basic types of malt, let’s look at how to get them into the beer. As a general rule of thumb, most beer recipes typically consist of 80 to 90% base malt (malt that still contains the amylase enzymes for saccharification of it, and additional specialty malts). This leaves the remaining 10 to 20% of the malt bill to be made up of specialty malt or other adjuncts (such as flaked or roasted grains or other sugars). If you are just beginning to experiment with specialty malts, it is a good idea to limit them to around 10% of the total malt bill. This way you will learn how each kind of specialty malt will affect the flavor and color of your beer without overwhelming a batch with any one or a combination of malts.
In order to include specialty malt in a batch of brew the first step is to crush the malt properly. The goal in crushing malt is to get each kernel of malt cracked open without excessively pulverizing it. Malt that is crushed too fine can lead to astringent flavors, poor extraction, or a stuck (clogged) mash. Malt that is not crushed fine enough may not give up all of its contents to the wort and result in a low rate of sugar extraction.
Malt should be crushed so each kernel is broken into four to six pieces without creating an excess amount of flour or tiny husk fragments (in the case of barley malt). Wheat or rye malt has no husk, but must also be crushed before use. Though it is possible to crush your malt with almost anything, a rolling pin, coffee grinder, flour mill, or blender, a malt mill equipped with specially designed rollers will achieve the most reliable results. If you have your own malt mill, it is best to crush the malt just prior to use and to do so in an area other than where your beer will ferment. This is to avoid contamination by bacteria or fungi floating around in the malt dust created during crushing.
I crush my malt out in my workshop with a single roller mill and ferment my beer in the basement to keep the two processes separate. There are many good malt mills on the market now, depending on the size and type you prefer. If you do not have your own malt mill it is best to have the malt supplier crush the malt for you when you purchase it.
Crushed or uncrushed malt should be stored in a dry, cool place. When storing malt, keeping it dry is more important than keeping it cool. Malt stored in the freezer can end up smelling or tasting like a freezer and should be avoided. Airtight plastic containers that do not have any residual flavors (from storing things like pickles) are the best way to prevent malt from picking up stray flavors or moisture. It is best to use specialty malts within a year of purchase to get the most flavors from them.
Next you’ll need to determine if the specialty malts you are going to use can simply be steeped or require mashing. Crystal malts and any dark-roasted malt may be steeped to extract their goodness. However, if you plan to use any base malt such as pale, Pils, Vienna, Munich, wheat or rye that have not been darkly roasted, you will need to conduct either a partial or full-scale mash to complete the conversion of starch to sugar. If you are not sure if your malt should be steeped or mashed, conduct at least a partial mash to be sure you get the desired results from your malt.
If you are using liquid or dry malt extract as the backbone of your beer recipe and plan to use specialty malts that do not require mashing for conversion (such as caramel or crystal malt), then steeping is the easiest way to go. To steep your crushed malt, place it in a nylon or muslin grain bag (available from most homebrew suppliers) and put it in enough 130–170 °F (54.5–76.5 °C) brewing water to completely immerse the malt. Leave the bag of malt in the water for 15 to 20 minutes, stirring the water with the bag every few minutes.
After steeping, lift the bag out of the water with a sieve, then ladle about a quart of the water over the bag to strain the malt a bit more, allowing the liquid to run back into the steeping pot. Straining the malt with an excessive amount of water, with water hotter than 170 °F (76.5 °C), or squeezing the last liquid from the bag can lead to excessive extraction of tannins from the malt that can cause astringency in beer. Once the steeping is complete, dissolve the malt extract into the steeping water and continue on with the rest of your brewing process.
If you plan to use malt extract as the basis for you beer but wish to use some specialty malt along with base malts, then a partial mash is the way to go. A partial mash can be conducted with the same equipment used for steeping, but with more attention paid to temperature, water volume and time. To conduct a partial mash, heat 1.5 quarts (1.65 L) of water to between 150 and 158 °F (65.5 and 70 °C) for every pound (.45 kg) of specialty malts (and any other flaked or roasted grains) in the recipe. It is important to be precise with water volume and temperature as the mash thickness and temperature will be critical to success.
Place all of the crushed malt (and any other grains) in a grain bag and immerse it in the water and place the lid on your vessel to retain heat. Let the grain sit in the water for 45 to 60 minutes, monitoring the temperature every 10 minutes or so. If you have the water and grain bag in a pot that can be heated, you can apply heat in short 15 to 45 second bursts to boost the temperature if needed. If you increase the temperature a little too much, don’t panic, just add a little cold water to bring it back in range. If you have the water and grain bag in a vessel that cannot be directly heated, then keep some boiling water on the stove in case you need to add a small amount of it to adjust the temperature upward to keep the mash in the desired temperature range.
While your mash is resting, heat the same volume of water as you used for the partial mash to 168 °F (75.5 °C). At the end of the mash time, lift the bag of malt out of the mash water and place it in a sieve over the mash vessel and slowly pour the 168 °F (75.5 °C) rinse (sparge) water over the grain bag to rinse the rest of the sugars out of the mashed malt. Once the partial mash process is complete, the remaining malt extract called for in the recipe can be dissolved into the partial mash water and you can continue your brewing process.
If you plan to brew an all-grain batch of beer, include the properly crushed specialty malt(s) with the base malt and mash and sparge according to the recipe. The enzymes from the base malt should convert the starch in the specialty malt(s) to sugar, and the sparge water will carry the sugar, flavor and color compounds of the specialty malt into the wort.
Be aware that Munich malt does not usually possess the diastatic power to convert other specialty malts and should be limited to less than half of the malt bill. Also, both wheat and rye malt have a high diastatic power but do not have a husk like barley malt to serve as a filter in the mash. Wheat or rye malt may be mashed successfully in a grain bag when employing a partial mash, but will require either a base (barley) malt or rice hulls to provide a proper filter in a full scale mash.
Learning to use specialty malts will open a new world of colors, flavors, and styles of beer you can brew. Knowing how to include each type of specialty malt will take you as a brewer, to the next level.
