We get this question a lot because there are quite a few different Crystal Malt grains available on our website, all with a different “L” (Lovibond) number.
In short, all Crystal Malts are rated by their level of roasting using a degree system called Lovibond (“L”).
The longer the crystal malt is roasted, the higher the Lovibond number. For example, a 10L Crystal Malt will have a light caramel and sweet quality and contribute minimal color, while a 90L Crystal Malt will have a richer flavor of slight burnt sugar, raisins, or prunes. With each step higher in the Lovibond scale, the crystal malt will have a slightly different flavor characteristic and mouth feel.
Crystal malts do a number of great things for your beer including helping with its mouth feel, head retention, and also gives the beer different flavors (depending on the L): caramel sweetness, burnt sugar flavors, toffee flavors, raisiny flavors, etc., and will also help contribute slightly to the color of your beer.
We would recommend checking out each of the Crystal Malts on our website. Each has a flavor characteristic associated with the Lovibond number. This will help give you a better idea what flavors you can expect to get from the different “L” for each Crystal Malt.