Malted barley has many forms. In brewing, we speak of two categories: base malts and specialty malts. A base malt is the main star: a nicely modified, malted grain that easily converts its starches to sugar in the right environment (the mash). Base malts absolutely have signature flavors and characters–but specialty malts are, for lack of better word–special. Typically used in a much smaller percentage within a recipe, they contribute stronger flavors: caramel, roast, nutty, smoky, bready or toasty characters, for example. The expression of these flavors depends greatly upon type. It’s good to note that specialty malts are not required to make a (good) beer–in fact, some notable beers are brewed with just one base malt (say, a SMASH, many English Barleywines, some pilsners, Märzens, etc.). But there are lots of great options to add additional flavors from said specialty malts. Who wouldn’t want more flavor to play with!
There are many kinds of specialty malts, it turns out, and it can help to understand how they’re processed. To borrow from John Mallett, author of the definitive guide and scholarly publication Malt, you can see specialty malt falling into essentially five categories. And while I could easily spend a book’s worth of blogging time on the malting process alone, here I just want to highlight some of the special products, so you might have more understanding of the delicious beverage in your glass or perhaps the one working on your homebrew system. If you need a refresher or would like to dive into learning more about the fascinating malting process, I recommend this fantastic presentation from Briess.
High-Dried or Extra Kilned
These malts start out similar to any base malt, but undergo a longer and hotter drying time in the kiln, which can bring out toasty and bready notes. A little extra color can go a long way in flavor production. Munich malt is made in this fashion, and is responsible for some lovely polished toasty German beers. Vienna malt is also a high-dried malt. Classic Vienna Lagers are somewhat hard to find these days, but they typically use Vienna malt at a majority or entire percentage in the malt bill. But used in conjunction with standard base malts, high-dried malts add complexity and malt presence, intrigue and interest.
Caramel or Crystal
These malts literally undergo a caramelization in their husks during the malting process, converting starches to sugars just like the mashing process in the brewhouse does. That’s a step beyond the normal process in the malthouse, however. This can be an advantage as far as recipe development is concerned, and allows brewers to add sweet and light candy-like notes to a beer as desired. That said, caramel or crystal malts should be used with care, as it’s easy to include too much and tip the balance of a recipe to too sweet or syrupy.
Roasted malts are exposed to higher temperatures, which in turn brings about roasty flavors. A drum roasting method is usually used, which rotates the grain and provides an even roasting temperature. Chocolate malt and black malt are two types in this category. Interestingly, one method for roasting coffee beans is somewhat similar. No wonder coffee stouts make so much sense!
Alternate Grains and Gluten-Free
Anything besides barley is considered an alternative grain. Most alternative grains have some sort of drawback and difficulty in the brewhouse if used at a high percentage in a recipe–there are many good reasons why barley has been the grain of choice for brewing for so long. Wheat, rye, oats, and other grains including sorghum, buckwheat (technically a seed), triticale, spelt and rice can all be malted and used in the brewhouse. Some of these are indeed used for brewing gluten-free beers, which are truly a field of their own. More common is to use an alternative grain at a small percentage to add flavor, mouthfeel, character, haze, etc. You are familiar with wheat beers, but also think about roggenbiers, oatmeal stouts, Asian rice lagers, etc. There are plenty of fun examples.
Some specialty malts don’t fit into the above categories very easily. They may have an additional procedure during the malting process, or skip over one entirely. Examples of these are smoked malts, peated malts, acidulated malts, roasted and unmalted grains, dehusked or debittered malts, and flaked pre-gelatinized grains (which you commonly know as breakfast porridge). And we can’t forget malt extracts–liquid syrups or powders that allow brewers (most often homebrewers) to skip all or part of the mashing process and just add malt sugars directly to their boil.
There’s a whole world of exciting malt out there–I hope you explore with sensory abandon and appreciation. Cheers!