The Real Reason Your Candy Bar May Look Dusty

You may have noticed from time to time that a chocolate bar will appear to have a dusty coating on its exterior, like it was dipped in some kind of white powder that was wiped off just before packaging. That's not powdered sugar added for extra sweetness, though, and the reason for it has more to do with chemistry than cleanliness or aesthetics.

According to Taste of Home, this dusty-looking coating is called a "chocolate bloom." It can occur when chocolate reforms after being partially melted, or when it is put into a humid environment, like the refrigerator. While it might look suspicious, these candy bars are perfectly safe to eat. The chocolate might taste a little different than you're used to, but there won't be any real harm done.

Asher's Chocolate Co. points out that there are two main types of bloomed chocolate: One is caused by the fats found in the chocolate, and the other by the sugars.

According to MSU Extension, sugar blooms in chocolate are caused by excess moisture in the environment — when there is too much water in the air, it can collect on the surface of the chocolate. This draws out the sugar, and then when the water evaporates again, it leaves behind a chalky, white coating of sugar crystals on the chocolate's surface.

The cause of chocolate blooms is the fats found in cocoa butter. Alpha Foodie says that the fats found in chocolate can arrange themselves into six different forms of crystals. The most desirable is Form V, which typically gives chocolate a shiny gloss and sharp snap when bitten into. Chocolatiers obtain this form through a careful manipulation process known as tempering, which usually involves careful temperature control and a lot of stirring. If done improperly, it can cause these chocolate blooms as the fats set into any of the other crystal forms. It can also occur in chocolate that has melted in high temperatures and has then been allowed to set again.

Ultimately, there's nothing wrong with eating chocolate that has bloomed. As those with sweet tooths know, a day with imperfect chocolate is better than a day without any at all.