The Oxford Companion to Beer definition of
Munich Malt was first developed as a color and aroma malt by the Spaten Brewery of Munich, Germany in the late 1830s. It was dried using a then-revolutionary, indirectly fired kiln, a change from the direct-fired kilns of the day. See wheeler, daniel. This allowed Spaten to make a homogeneous malt with predictable brewing characteristics. The first beer style made with the new Munich malt, in 1841, is now known as märzen, which is also the forerunner of the oktoberfestbier. Its color is in the mid-20s EBC (approximately 10 SRM, light brown), only half as dark as the standard dunkel of the day with a typical color rating in the mid-40s EBC (approximately 17–20 SRM, dark brown). Outside Vienna, incidentally, a similar malt was developed contemporaneously by the Dreher Brewery. This Vienna malt led to the Vienna lager with a color rating in the mid-30s (approximately 13°L). Munich malts are available in a broad range of colors, from a low of 12 EBC (approximately 5°L) to a high of more than 30 EBC (approximately 12°L). Unlike other aromatic malts—such as caramel, chocolate, and roasted—Munich and Vienna malts are kilned gently at perhaps 50°C to 70°C (roughly 120°F to 160°F) until the moisture content has dropped to 10% to 20% to preserve much of their starch-reducing diastatic enzymes. Any remaining moisture is then quickly driven off during a quick final curing at approximately 110°C (230°F). This initiates the melanoidin-producing Maillard reaction. Melanoidins give beer malty-sweet aromas and deep color. The retention of enzymatic power is important, because this allows Munich malt to be used as a base malt, where it can lend deep malt flavors to beers styles such as märzen.
See also base malt, dunkel, european brewery convention (ebc), märzenbier, standard reference method (srm), and vienna lager.