What Causes Bloom in Chocolate?

What Causes Bloom in Chocolate?

There are two types of bloom. One is caused when the cocoa butter, reacting to heat, separates from the other ingredients. It rises to the surface of the chocolate forming pale irregular spots or blotches. This is known as fat bloom. It can be wiped off with a paper towel but it is not necessary to do so. Sugar bloom looks similar but has a slightly gritty texture. It is caused by damp, humid conditions that encourage moisture build up on the surface. This “sweat” dissolves some of the sugar in the chocolate. When it re-crystallizes, a dusty coating is produced that cannot be removed.

Bloom has nothing to do with the age of the chcolate. It can happen to just purchased treats that are left in a hot car. When the partially melted morsels re-harden at home they are prone to get the characteristic white speckles of fat bloom. The same thing can occur when summertime temperatures soar up into the 90's. If you don’t have central air conditioning, your kitchen cupboards heat up, creating ideal conditions for bloom.

Putting a brand new partially used and loosely closed package of baking bars in the refrigerator can trigger sugar bloom because it’s such a moist environment. A long period of warm rainy days can have a similar effect on the chocolate in your pantry because the relative humidity in your home is likely to rise above 55%.

But bloom is only a change in appearance. It’s not a sign that chocolate is old or has gone bad. Now that you know there’s nothing wrong with chocolate that’s not picture perfect go ahead and use it to make something wonderful. Cheers!