Fat bloom is recognized as a greyish-white sheen on the surface and is predominantly triggered by the exposure of chocolates to excessive temperatures for prolonged periods. The optimum temperature for chocolate to be stored is between 57-61°F. If chocolate is exposed to high temperatures, the delicate and low melting point of the cocoa butter triggers it to melt and rise to the surface and then re-solidifies where it sets as grey streaks, which we refer to as fat bloom. While visually undesirable, products are still edible but the flavor and texture is compromised. It is perfectly fine to use for baking. See ‘How do I best store chocolate’ to ensure the chocolate remains in the best condition.