Asked by: BBC Focus - The Great British Bake Off Q&A special
Unlike bread and cakes, which tend to become hard the longer they spend in the air, most biscuits go soft over time. As in bread, starch from the flour in biscuits begins to crystalize after a few days, theoretically making biscuits more brittle. But in many biscuits, the high sugar content masks this process by absorbing water from the atmosphere, ultimately resulting in a soft biscuit.
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