malt syrup is an unrefined sweetener derived from germinated (sprouted) cereal grains, typically barley, in combination with other cooked grains. If malted barley alone is used, the resulting syrup may be called “barley malt extract,” or just “malt extract,” and the malt aroma will be more intense. Malt syrup is used in bread and other baked goods, jams, breakfast cereals, confectionery, and in brewing beer.
The first step in malting grains is to put them in a dark room and soak them in water. The germinating grains produce enzymes that convert starches into sugar to fuel growth. (Barley produces unusually active and abundant malt enzymes.) The maltster then halts enzymatic activity by quickly drying the sprouting seeds, which kills the seed embryo and preserves its nutrients. The malted grains are crushed, steeped in hot water, and mixed with cooked grains (unless it is a malt extract, in which case cooked grains are not added). Malt enzymes digest the starch present in the cooked grains, forming a slurry that is concentrated and evaporated by boiling off the water, or, in modern food-grade malt plants, by using a vacuum evaporator. The sticky dark brown syrup that is left is about half as sweet as table sugar, with a distinct flavor some have described as biscuity, honeyed, or, depending on the kilning technique, roasted, with chocolate and coffee-like flavors.