In brief
Overwhipped cream can become grainy and lose its airy texture.
Useful to know
Overwhipped cream can become grainy and lose its airy texture. King Arthur demonstrates improving it by gradually adding cold, unwhipped cream at low speed. [1]
Add small amounts while watching the mixture rather than pouring in one large quantity. The amount needed depends on how far the structure has changed, and the technique cannot repair every possible end state. Next time, reduce the speed near the finish and check frequently. Thick foam can begin separating quickly.
Sources
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