How do I store chocolate so it does not go white?

The white or grey film on old chocolate is bloom, not mould. There are two types with two different causes, and both come from storing chocolate somewhere it did not want to be.

Step by step

1. Store it at 15 to 18°C.A cool cupboard, a cellar, or the coolest room in the house. Chocolate is stable in a fairly narrow band and both ends of the range cause problems.
2. Keep it wrapped.In its own foil and paper, or an airtight box. Cocoa butter absorbs smells readily, which is why chocolate stored beside coffee or spices tastes of them.
3. Keep it away from light.Light and heat together accelerate the fat separating out. A closed cupboard, not a worktop.
4. Understand fat bloom.Cocoa butter migrating to the surface and recrystallising, caused by warmth or temperature swings. It looks like a pale grey film and the chocolate feels slightly soft or greasy.
5. Understand sugar bloom.Moisture condensing on the surface, dissolving sugar and leaving crystals behind as it evaporates. It looks white and gritty and is caused almost entirely by the fridge.
6. Avoid the fridge unless the house is genuinely hot.If you must refrigerate in a heatwave, seal it in an airtight bag first and let it come back to room temperature still sealed, so condensation forms on the bag rather than the chocolate.
7. Know the shelf lives.Dark chocolate two years, milk about a year, white about eight months. Milk and white contain milk solids that go stale sooner.
8. Use bloomed chocolate for cooking.It is harmless and melting it restores everything. Bloom only matters for chocolate eaten as it is, where the snap and gloss are the point.
9. Keep couverture separate.If you temper chocolate, store the good stuff at a stable temperature and never in the fridge — tempering is destroyed by bloom and has to be redone.

Tips

• A cool cupboard beats the fridge in almost every UK kitchen.
• If you do refrigerate it, seal it first and unseal it only once it is back at room temperature.
• Bloomed chocolate is fine to cook with — melting resets it completely.

Common mistakes

• Keeping chocolate in the fridge as a default — The cold surface attracts condensation every time the door opens, which dissolves surface sugar and leaves a gritty white crust. It also picks up the smell of everything else in there.
• Storing chocolate next to coffee, spices or cheese — Cocoa butter is highly absorbent and takes on surrounding aromas within days. Chocolate stored in an open cupboard beside strong-smelling goods tastes noticeably of them.

If it doesn't work

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