Pumpkin purée

One US cup of pumpkin purée weighs 245 grams. Going the other way, 100 grams is about 0.41 cups.

Canned pumpkin purée is one of the ingredients where King Arthur's chart quietly repeats its fluid-ounce-as-weight convention. King Arthur publishes 1 cup at 227 grams, which implies a density of 0.9595 grams per millilitre — lighter than water. Canned pumpkin is 90.5 percent water plus fibrous solids that are themselves denser than water, so the mixture must be denser than water, not lighter. The number is physically impossible.

The 227 figure is what you get when 8 US fluid ounces are read as if they were 8 weight ounces (8 × 28.35 = 227). It appears across King Arthur's chart on milk, yogurt, heavy cream, Greek yogurt, vanilla extract and now pumpkin — anywhere the row happens to have been filled in by that conversion rather than by a scale reading of the actual product. We reject the King Arthur figure on the same physical grounds we reject it for the dairy products in that list.

USDA FoodData Central publishes 1 cup of canned pumpkin (without salt) at 245 grams (FDC 168450), which implies a density of 1.0355 grams per millilitre. That fits the physics: canned pumpkin is very close to water in density, slightly denser because the pumpkin solids are denser than the water they sit in. Roughly 90.5 percent water, 1.1 percent protein, 8.1 percent carbohydrate (of which 7.1 grams per cup is fibre) and 0.3 percent fat, per USDA's own composition breakdown.

Two related products should not be confused with canned pumpkin purée. Pumpkin pie mix is canned pumpkin plus sugar and pumpkin-pie spices, and weighs substantially more per cup because of the added sugar — USDA lists it at 281 grams per cup for a density of 1.187 grams per millilitre. Fresh pumpkin purée, made at home by cooking and blending a whole pumpkin, has more variable density depending on how much moisture cooks off and how finely it is blended; USDA's canned figure is a reasonable starting estimate.

Libby's dominates the canned-pumpkin market in the United States, and much of what USDA sampled would be Libby's or comparable pack. Other brands (Farmer's Market, Trader Joe's, Whole Foods 365) publish nutrition labels within a few grams per serving of Libby's, so the entry represents canned pumpkin purée generally rather than one specific brand. Any brand marked '100% pure pumpkin' will be close to this figure.

FDA has no identity standard for canned pumpkin purée. The Codex Alimentarius has no standard for pumpkin. There is no third source qualifying for high confidence — USDA plus the physics-based rejection of King Arthur is the sourcing envelope for this entry.

The category here is 'liquid' rather than 'sugar' or 'milled' because canned pumpkin behaves as a semi-liquid paste in a measuring cup: it settles into the container without gaps, and the density is set by the water it contains rather than by how it was scooped. The 5 percent liquid category tolerance would apply if there were a second accepted source; since there is not, the entry is medium confidence on the strength of the single USDA measurement plus the well-established physics.