Canola oil

The only published measurement for a US cup of canola oil is 218 grams. One source is not enough to publish it as this site’s figure, so it is shown below with where it came from and what is still missing.

Also called rapeseed oil, low erucic acid rapeseed oil, colza oil.

The first entry where USDA's own portions disagree with each other. FDC 172336 publishes a cup at 218 g (0.9214 g/ml), a tablespoon at 14 g (0.9468 g/ml) and a teaspoon at 4.5 g (0.9130 g/ml), a spread of 3.7%. This is unlike olive oil, where USDA's cup, tablespoon and teaspoon all resolve to a single density rounded three ways.

The cup is the only one of the three whose rounding is tight enough to carry a density: at the nearest whole gram, 218 g admits 0.9193 to 0.9235 g/ml, a band of 0.5%. The tablespoon cannot. Fourteen grams is a whole number appearing identically across every canola product USDA lists, including the corn-and-canola blend at FDC 169867, which is the signature of a labelling convention rather than a measurement; its rounding band is 3.6% wide, wider than the quantity being measured.

The teaspoon at 4.5 g carries the whole density in one decimal place and is no better. Codex Alimentarius CXS 210-1999 specifies relative density for low erucic acid rapeseed oil as 0.914 to 0.920 at 20C, determined per IUPAC 2.101. USDA's cup figure of 0.9214 sits 0.15% above that ceiling.

The lower edge of USDA's rounding band does fall inside the Codex range, and an earlier draft of this entry published 0.9214 on that basis. The validator refused it, correctly: a figure that falls outside a standard consulted for the entry cannot be published because an argument can be constructed for why the gap does not count. Every wrong number in every converter on the internet has such an argument behind it.

Nothing is published here until a third source settles whether the true value is at the Codex ceiling or just above it. This is a narrower question than flour's, where three sources measured three genuinely different quantities; here two sources disagree by a fifth of a percent about one quantity, and the honest position is that the dataset cannot yet tell which is right. Two further cautions on the standard: its table describes crude oils, while retail canola is refined, and the standard notes that characteristics vary with origin and growing conditions.

Canola and low erucic acid rapeseed oil are the same product under different names, the former being the North American trade name. Oil, industrial, canola, high oleic (FDC 171042) is a different product and is not covered by this entry. Density falls as temperature rises, so oil measured warm weighs slightly less per cup than the same oil measured cold.