Evaporated milk

One US cup of evaporated milk weighs 252 grams. Going the other way, 100 grams is about 0.40 cups.

Evaporated milk is regular whole milk with about 60 percent of the water removed by heating under vacuum. The result is a thick, shelf-stable liquid roughly twice the density of milk solids, sold in cans and used in coffee, pumpkin pie custards, key lime pie, tres leches cake, savoury cream sauces where milk would be too thin, and traditional dishes across Latin American, Filipino and Southeast Asian cuisine where refrigerated dairy is historically less available.

USDA FoodData Central publishes 1 cup of evaporated milk at 252 grams and 1 tablespoon at 16 grams (FDC 171267, Milk, canned, evaporated, not reconstituted). That gives a density of 1.0651 grams per millilitre. King Arthur's ingredient weight chart publishes 1/2 cup at 113 grams, which extrapolates to 226 grams per cup and 0.9553 grams per millilitre.

The two figures are far apart, and the King Arthur figure is physically impossible. Regular milk is roughly 88 percent water and has a density of 1.03 grams per millilitre — slightly above water because milk solids are denser than water. Removing 60 percent of the water leaves a product that is roughly 74 percent water with concentrated protein, lactose and fat. This mixture must have a higher density than regular milk, not a lower one. USDA's 1.0651 gram per millilitre figure matches the physics; King Arthur's 0.9553 does not. This is the ninth entry on this site where King Arthur's chart uses the eight-fluid-ounces-times-28.35-grams convention (or in this case, four fluid ounces times 28.35 for the half-cup row) to fill in a dairy row that has not been measured against a scale.

Standard US cans of evaporated milk are labelled 12 fluid ounces, which corresponds to 1.5 cups by volume or 378 grams by weight at USDA's density. Larger 5-fluid-ounce cans are 148 grams. Most recipes calling for evaporated milk assume the 12-ounce can as the reference, and 'one can' generally means the full 378 grams regardless of the volume conversion.

Evaporated milk should not be confused with sweetened condensed milk, which is a completely different product. Sweetened condensed milk has both water removed and sugar added, producing a much sweeter and denser final result (306 grams per cup at 1.29 grams per millilitre). Recipes are not interchangeable: substituting evaporated for sweetened condensed will remove all the sweetness from the recipe, while substituting the other way will add sugar and change the texture completely.

Related products this entry does not cover: evaporated skim milk (lower fat, weighs about 256 grams per cup because more water remains proportionally when the fat is removed); powdered milk reconstituted with less water to approximate evaporated milk (density varies, texture is different); and cream-condensed milk products such as evaporated cream or table cream, which have higher fat content.

FDA identity standard for evaporated milk is at 21 CFR 131.130, requiring not less than 6.5 percent milkfat and not less than 16.5 percent nonfat milk solids, plus a minimum total milk solids of 23 percent. Codex Alimentarius standard CXS 282-1971 (Standard for evaporated milks) covers the international identity requirements. Neither publishes a density, but both indirectly constrain it through the composition minimums.

The category here is 'liquid' rather than 'sugar' or 'milled' because evaporated milk behaves as a thick liquid in a measuring cup: it pours (slowly), self-levels, and the density is determined by its water and solids content rather than by how it was measured. The 5 percent liquid tolerance would apply if there were a second accepted source; since King Arthur's figure is rejected, the entry is medium confidence on the strength of the USDA measurement plus the physics-based rejection.