Pale malts
Pale malts, often referred to as pilsner malts, pilsner-style malts, or lager malts, are distinguished by their very light color (up to 5 EBC). The lightest in this group are green malt and enzymatic malt. Green malt is now used relatively rarely due to its exceptionally short shelf life (green malt is only gently dried to stop the growth process). More durable enzymatic malt is prepared specifically for customers for whom a high enzyme content is very important (including whisky producers).
Pale malts have a mild, slightly grainy, nutty, cereal-like flavor and aroma. They contain an optimal amount of proteolytic enzymes (proteases), which break down the proteins contained in the wort, and amylolytic enzymes (amylases), responsible for breaking down starch into fermentable sugars. Due to the lower malting temperature, pale malts may contain more precursors of dimethyl sulfide (DMS) and other substances that introduce vegetable-like aromas into beer. In the case of some malts, therefore, intensive boiling during hopping and cooling the wort below 70 degrees Celsius as quickly as possible are required.
Ale-type malts
These malts, most commonly referred to in Europe as pale ale or ale malt, are only slightly darker than pilsner malts (color up to 7 EBC). The difference is so small that not all consumers are able to notice it. Ale-type malts contain slightly fewer enzymes than pilsner malts and contribute somewhat more malty, biscuity notes to beer. Traditionally, they form the base for Belgian and English beers. In some countries, such as the Czech Republic, ale-type malt is often identified with Vienna malt.
Vienna malts
Vienna malts (or Vienna-style malts), due to their higher drying temperature, contribute many sweet, malty and slightly caramel aromas to beer. Their color usually does not exceed 10 EBC, and their enzyme content is slightly lower than that of pilsner malts. Vienna malt is traditionally used as grist in German and Austrian Vienna lagers. It gives beer a deep golden color.
Munich malts
Munich malt usually comes in two variants: light Munich (with a color of up to 20 EBC) and dark Munich (usually up to 25 EBC, although values as high as 35 EBC also occur). When brewers and beer enthusiasts talk about malt aroma, they most often mean the aroma of light Munich malt, dried at a temperature of 110-120 degrees Celsius. Munich malt is most often used for darker beers in the style characteristic of Munich, i.e. full-bodied, darker lagers. It gives beer a dark golden color and distinctly perceptible caramel aromas.
Caramel malts
During the roasting of green malt at high temperatures, the starch first undergoes partial saccharification, after which the sugars begin to caramelize. Due to the complexity of the process, which is influenced, among other factors, by the barley variety, maltsters carefully guard their recipes. As a result, caramel malts from different producers show significant differences. Roasting should be supervised by an experienced specialist, who decides when to end it and quickly cool the malt. Depending on the roasting time and intensity, caramel malts have different colors and flavors: from sweet, cereal-caramel notes to the deep, dry, caramel-chocolate notes characteristic of dark caramel malt. Some caramel malts (especially those with a color of around 70 EBC and darker) may have increased acidity, which has a beneficial effect on flavor and foam stability.
Biscuit malts
These malts, also known as cookie or biscuit malts, have low diastatic power. They are relatively dark—their color reaches 60-70 EBC. Unlike caramel malts, they are produced by roasting finished pilsner malt. They are distinguished by complex toasty or biscuity aromas, reminiscent of roasted corn. They usually account for up to 20 percent of the grist.
Dextrin malts
During production, these malts undergo partial gelatinization inside the grain before the drying process begins. As a result, starch broken down by enzymes forms dextrins, which have a positive effect on foam formation and increase beer body. Although dextrin malt is not roasted, it develops pleasantly sweet, malty and caramel flavor and aroma notes.
Smoked malts
Smoked malts differ from one another depending on the production process. In some malt houses, smoke is used while the malt is being dried; in others, the finished malt, most often pilsner malt, is exposed to smoke. In the first case, the smoke aroma penetrates the grain more deeply and is more intense; in the second, it settles mainly on the malt husk, so it weakens during brewing but is more complex and contributes more smoky and fruity nuances to the beer. Depending on the process used and the type of wood, smoky aromas may evoke a campfire, smoked meat, oscypek cheese, cloves and other spices. Soapy, estery or peaty aromas may also appear, reminiscent of hot asphalt, furniture polish and railway sleepers.
Roasted malts and roasted grain
Finished pilsner malt is used to produce coloring malts. In addition to black color, they contribute, among other things, coffee, chocolate, roasted and ash-like aromas to beer. To limit their intensity, dehusked malt can be used or it can be added toward the end of mashing. Roasted grain can also enrich the aroma of beer. Roasted barley and roasted rye are used most often. It should be remembered that dark malts slightly lower the pH value of the mash, which is important because dark beers should be mashed within a somewhat higher pH range.
Acidulated malts
Acidulated malts are used in some regions of Germany to comply with the purity law in force there (Reinheitsgebot). When it is necessary to lower the pH value of beer at the initial stage of the process, acid is not used; instead, malt sprayed with acid or malt on which lactic acid bacteria have naturally produced acid is used. In most styles, this has no significant effect on flavor, but in sour beers or beers brewed using the sour mash process, the bacteria developing on the malt may contribute aromas to the beer that are more complex than ordinary lactic acid.