Black malt extract is the darkest of the common roasted malts.
Black malt provides the color and some of the flavor in black porter, contributing an acrid, ashy undertone to the taste. In small quantities, black malt can also be used to darken beer to a desired color, sometimes as a substitute for caramel color.
- Due to its high kilning temperature, it contains no enzymes.
Source: Wikipedia, https://en.wikipedia.org/wiki/Mash_ingredients