Masa harina

One US cup of masa harina weighs between 93 and 114 grams, depending on how the cup is filled and which source measured it. That range is the answer; a single number would not be. Every figure behind it is below, with the method each source used.

Masa harina is dried, ground nixtamalized corn — the essential flour of Mexican and Central American cooking, used to make corn tortillas, tamales, pupusas, huaraches, gorditas, and atole. The Spanish name translates literally as 'dough flour', and that describes its purpose exactly: mixed with water, it reconstitutes into masa, the corn dough that predates the arrival of wheat flour in the Americas by several thousand years.

USDA FoodData Central lists corn flour, masa, unenriched at approximately 114 grams per cup, giving a density of 0.4818 grams per millilitre. King Arthur's ingredient weight chart publishes 1 cup at 93 grams and 0.3931 grams per millilitre. The two figures are 20 percent apart, well outside the 10 percent tolerance we apply to the milled category, so we publish the range 93 to 114 grams per cup rather than a single figure. The manufacturer specifications from Maseca (the dominant US brand) and Masienda both list approximately 114 to 116 grams per cup, aligning with USDA and suggesting the KA figure is either a lighter measurement method or an under-measurement.

Nixtamalization is the process that distinguishes masa harina from regular cornmeal or corn flour. Dried corn kernels are soaked and cooked in an alkaline solution (traditionally slaked lime, calcium hydroxide dissolved in water) which loosens the outer skin, softens the kernels, and chemically transforms the corn in several important ways. The niacin in corn becomes bioavailable (untreated corn causes pellagra when it forms most of a diet, as European colonists in the Americas learned the hard way); the calcium content increases dramatically (about 20 times more calcium than regular cornmeal); the amino acid profile becomes more complete; and the starch structure changes so that the resulting dough is pliable and holds together in tortilla form — a texture regular corn flour cannot produce.

The distinction from cornmeal is critical for anyone substituting between them. Regular cornmeal (also in this dataset) is coarsely ground plain dried corn. Corn flour is finely ground plain dried corn. Neither is nixtamalized, and neither will produce a workable tortilla. Substituting cornmeal for masa harina yields a crumbly, non-pliable mixture that falls apart when shaped. The reverse substitution — masa harina in a cornbread recipe — produces a strange, alkaline-tasting result that lacks the sweetness of untreated corn.

Masa harina and masa are related but not identical. Masa is the wet nixtamalized corn dough, either freshly made in a tortilleria or reconstituted from masa harina at home. Masa harina is the dried, powdered form for storage and shipment. USDA lists masa (cooked) as a separate entry (FDC 785450 for Masa Harina Cooked, which is misleadingly named — it refers to the reconstituted dough). This entry describes the dry powder.

Related products this entry does not cover: corn flour (finely ground non-nixtamalized corn, sometimes marketed as 'corn masa flour' outside Latin American markets, which causes confusion); hominy (whole nixtamalized corn kernels, sold canned or dried, used in pozole); grits (coarsely ground white corn); and blue masa harina (from nixtamalized blue corn, used for blue-corn tortillas, similar density to yellow masa harina).

FDA does not have an identity standard specific to masa harina. Codex Alimentarius standard CXS 154-1985 covers degermed maize meal but not nixtamalized corn products. Neither publishes a bulk density.

The category here is 'milled' because masa harina behaves like other fine milled powders in a measuring cup — it clumps, bridges, and its density depends significantly on scoop method. The 10 percent tolerance applies, and the two source figures are outside it, hence the range publication.