Why does chocolate turn white?
No. It is bloom, and telling the two kinds apart tells you what went wrong and how to prevent it.
If you read nothing else
Smooth and slightly greasy is fat bloom, from warmth. Rough and gritty is sugar bloom, from moisture. Both are safe; neither is mould.
Telling the two apart
Touch it. Fat bloom feels smooth and faintly greasy, and often appears as streaks or a general dulling. Sugar bloom feels rough and gritty, and appears as fine speckles or a dusty film. That single test identifies the cause and therefore the fix.
If it is fat bloom
The chocolate has been too warm, or has cycled between temperatures, or was poorly tempered in the first place. Store at a steady 15–18°C rather than somewhere that swings — the swinging matters more than the average.
If it is sugar bloom
Moisture has reached the surface, almost always from refrigeration or from a damp environment. Keep chocolate out of the fridge; if refrigeration is unavoidable, wrap airtight and let it reach room temperature before unwrapping.
What to do with it
Eat it — the texture is compromised and nothing else. Or better, cook with it: melting destroys the crystal structure entirely, so bloomed chocolate makes a perfectly good ganache, brownie or hot chocolate with no trace of the problem.
Covered in this guide
- Chocolate bloom explainedThe full mechanism behind both kinds.
- Making ganacheThe best use for a bloomed bar.
Sources
- ChocolateHQ editorial synthesis — ChocolateHQ(citation identity confirmed; passage not re-read)