You've had that bar of baking chocolate in the pantry for months, and maybe you've just grabbed it for a recipe and noticed it looks a little... off. Maybe there's a powdery film on the surface, or the whole thing looks a little cloudy. Not quite like the creamy chocolate you're used to. But no worries, this chocolate is still delicious and ready for your next baking project (or mid-day chocolate snack emergency!)
When chocolate has been improperly handled, it forms a gray or white cast on the surface known as bloom. There are two types of bloom that occur on chocolate, each from a different cause.
FAT BLOOM is caused by either improper tempering of chocolate or by exposure to high temperatures during storage. Fat bloom is cocoa butter that has come to the surface of the chocolate and set, resulting in gray streaks or spots on the surface of the chocolate.
SUGAR BLOOM is caused by exposure to moisture, usually in the form of high humidity. This type of bloom is actually tiny crystals of sugar that have formed on the surface of the chocolate after the moisture evaporates, resulting in a whitish film on the chocolate.
It is difficult to distinguish between the two types of bloom based on appearance, and neither type of bloom is harmful other than to the appearance and texture of the chocolate. Fat bloom can result in a soft or a grainy texture, but it will completely disappear once the chocolate is remelted and tempered properly, or mixed into other ingredients for a recipe. Sugar bloom will also disappear without adverse effect when the chocolate is remelted and tempered, as long as the moisture that caused it has evaporated before the chocolate is used. You can still enjoy any confections exhibiting bloom without concern, even though they do not have the polished appearance that you strive for.
