Heavy Cream or Heavy "Whipping" Cream has 36 - 40% butterfat and when whipped it holds its form and doubles in volume. Heavy cream is used for filling and decorating
pastries
.
Whipping Cream has a butterfat content of 30%. It whips but not as well as heavy cream, and will not hold its form long. Good for fillings but does not hold up well for piping.
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whipped cream is whipped cream it can't be substituted for heavey cream