We've all experienced that moment where we open chocolate we'd been saving, maybe from Easter or some we'd brought back on holiday, to find a bit turned a lighter colour.
Why does it do that? Is it mould? Is it safe to eat?
We now know the answer.
If it changes colour, is it safe to eat? Yep.
The white powdery stuff is sugar bloom or fat bloom, which appears due to chemical changes in the chocolate.
Sugar bloom happens when the chocolate is exposed to too much moisture, and can be avoided by keeping it away from damp places and storing it in a cool, dry cupboard.
Fat bloom, on the other hand, is often a sign that the chocolate is made of less quality ingredients, like fat being used instead of cocoa.
Luckily for us living here in the EU, our chocolate products can't be made with less than 30% cocoa and 20% milk solids, unlike the US where they only need 10% cocoa. So we almost never get fat bloom.
If you want your chocolate to stay pristine, just store it well.