Storage, shelf life and quality defects
This domain tests whether you can keep chocolate in condition, recognise a fault when it appears, and distinguish storage defects from manufacturing ones.
Ideal conditions
Store at 15-18 degrees C with relative humidity below 50%, away from light, odours and vibration, in airtight wrapping. Chocolate absorbs volatiles readily, so never store it beside spices, cheese or cleaning products. A stable temperature matters more than a slightly warm one; fluctuation is the greater damage.
Fat bloom and sugar bloom
Fat bloom is grey-white streaking or a dusty surface caused by cocoa butter recrystallising, usually after warmth followed by cooling, or from a poorly tempered bar. The chocolate is safe but texture and snap suffer. Sugar bloom is a rougher, granular film from condensation: moisture dissolves surface sugar, which recrystallises as the water evaporates. Fat bloom is a temper and temperature issue; sugar bloom is a humidity and cold-chain issue. Both differ from dust or mould.
Shelf life
Typical best-before dates: dark 12-24 months, milk 6-12 months, white 6-9 months, nut-filled products shorter because nut oils rancidify. Bloom risk rises with poor tempering and warm storage; milk and white are more sensitive to off-flavours and moisture.
Other defects
Mould from damp storage; insect infestation in cracked or old stock; rancidity in inclusions; moisture migration between filling and shell causing soft centres, cracks or sugar migration; and condensation marks or sticking.
Worked example. A bar shows a dull grey haze but no roughness and snaps cleanly. That is fat bloom: cocoa butter has re-crystallised after a warm spell. Warm the surface gently; if the colour returns, it is bloom, not mould. It indicates a storage or tempering fault and the chocolate remains edible.
Traps. Refrigerating chocolate and creating condensation; blaming sugar bloom on tempering; assuming all white surface marks are mould; ignoring odour transfer; storing at fluctuating temperatures in a shop window.