Heavy cream

One US cup of heavy cream weighs 238 grams. Going the other way, 100 grams is about 0.42 cups.

Also called heavy whipping cream, whipping cream, double cream (British 48% fat is a distinct product).

The King Arthur figure for cream extends the same volume-to-weight conversion error already documented on the milk and yogurt entries, and adds a clearer proof that it is a convention rather than a measurement: King Arthur assigns a single weight of 227 grams to three products (heavy cream, light cream, and half and half) that have substantially different fat contents and therefore different densities. Half and half is 10 to 18 percent milkfat, light cream is 18 to 30 percent, and heavy whipping cream is a minimum of 36 percent under FDA identity standards. A bench measurement of the cup weight for these three products would produce three different numbers.

Applying the same 227 gram figure to all three demonstrates that the number is an 8-fluid-ounce serving converted as if the fluid ounces were weight ounces, not a measurement of what a cup of any specific cream weighs. The value is rejected under rule 7 rather than deleted, because a published figure that is wrong is worth knowing about, and this one is refuted by the products themselves rather than by an external standard. USDA FDC 170859 (Cream, fluid, heavy whipping, minimum 36 percent milkfat) gives a cup at 238 g, or 1.006 g/ml.

This is slightly above water because the aqueous phase of cream carries dissolved milk solids that raise the density enough to offset the presence of butterfat, and the balance falls just above water at the 36 percent fat level. Higher-fat creams sit closer to or slightly below water: British double cream at 48 percent fat is approximately 0.99 g/ml, and clotted cream at 55 to 60 percent is genuinely below water. These are distinct products from US heavy whipping cream and are not covered by this entry.

USDA also publishes a tablespoon at 15 g for the same record, and 15 times 16 gives 240 g, close to the cup figure. The 2 g difference reflects nutrition-label rounding on the small measure; the cup portion carries the more reliable density. Whipping cream (the lower FDA category at minimum 30 percent milkfat, sometimes labelled light whipping cream) is a distinct product that USDA lists separately at FDC 170858 with a cup portion of 239 g.

The density is effectively identical to heavy whipping cream at the precision published, since the 6-percent fat difference is within the rounding band. Light cream, half and half, single cream, coffee cream and pouring cream form a spectrum of lower-fat products with densities from about 1.02 down to 1.01 g/ml, each covered by its own USDA record and none matching King Arthur's 227 g figure. Whipped cream, which is the same product with air incorporated to double its volume, weighs roughly half as much per cup at 60 g (FDC 173441 pressurised, 120 g whipped from 1 cup fluid).

This is not a state of heavy cream in the sense used for coconut oil solid and liquid: it is a distinct food produced by mechanical aeration, and it belongs in its own entry. That leaves one accepted source. The entry is held at medium confidence until an independent second and third are found.

Dairy composition standards regulate milkfat content rather than density directly, so the Codex route that resolved olive oil is not available here.