What causes chocolate to bloom? (turn white)

So now we know what causes chocolate to bloom, now to identify what type of bloom has occurred.

Fat Bloom: Fat bloom in chocolate is caused by the cocoa butter within it. When the cocoa butter melts and then re-solidifies, it can create a dull white coating on the chocolate’s surface, making it lose its usual smoothness and shine. This undesirable effect is known as “fat bloom.”

Fat bloom typically happens for two main reasons. Firstly, it can occur due to incorrect tempering, which is the process of ensuring that the cocoa butter crystals are evenly distributed in the chocolate during its melting and solidifying stages. Secondly, fat bloom might happen if you store chocolate at too high a temperature, causing the cocoa butter to melt and rise to the surface.

So if you are leaving your chocolate in direct sunlight, in a warm cupboard or even leaving it in your car, you may see chocolate bloom appearing.

To prevent fat bloom, choose a cool, dark cupboard away from strong odours to store your chocolate goods.

Sugar Bloom: Chocolate afflicted with sugar bloom often develops a rough, whitish surface and a grainy texture. This type of bloom is usually the result of temperature changes or storing chocolate in a humid environment.

Temperature shock plays a significant role in sugar bloom. It occurs when you quickly shift chocolate from a warm or hot location (like an open shelf near the oven) to a cold one, such as the fridge. This abrupt change in temperature causes condensation to form on the chocolate’s surface, which then interacts with the sugar in the chocolate, leading to sugar bloom. For instance, if you place your chocolate molds in the fridge right after making them, you risk exposing them to temperature shock. To prevent sugar bloom, allow your chocolates to cool down at room temperature before refrigerating them.