Cornmeal, Grits And Polenta Are One Grain Ground Three Ways

Three products made from corn sit in different aisles and different cuisines. What separates them is mostly how coarsely the grain was ground and what was removed first.

Grind size sets the cooking time

Water has to reach the center of each particle before the starch can swell and gelatinize. Larger particles take longer, and the relationship is not gentle.

Fine cornmeal hydrates quickly, which is why cornbread batters come together in minutes. Coarse grits and polenta need long, slow cooking to soften the same way.

Instant versions of both are precooked and dried, which is why they hydrate in minutes and why the texture is softer and less distinct than the slow version.

Degerminated and whole grain are different products

The corn kernel has a germ that contains oil. Removing it extends shelf life considerably, because that oil is what goes rancid.

Most supermarket cornmeal is degerminated for that reason. Stone-ground whole-grain meal keeps the germ, tastes more strongly of corn, and needs cold storage.

Anyone who has found a bag of stone-ground meal that smells sour in a warm cabinet has met the tradeoff directly. Refrigeration or freezing is the answer.

Hominy and grits involve an extra step

Some grits are made from hominy, corn treated with an alkaline solution in a process that loosens the hull and changes the flavor and the nutrition.

That process is also what makes masa for tortillas and tamales, which is why masa harina cannot be replaced by plain cornmeal in those recipes.

Untreated grits exist as well, so the label rather than the word grits is what tells you which product is in the bag.

The variety of corn matters

Grits in the South are traditionally made from dent corn, while some polenta is made from flint corn, and the two have different starch structures.

That affects how the cooked porridge sets. A firmer-setting variety is what allows cooled polenta to be sliced and pan-fried, which softer meals resist.

In practice most supermarket products are interchangeable if the grind matches, and the grind is the substitution that actually needs checking.

Substituting without ruining the dish

Swapping a coarse product into a fine application leaves grit in the finished texture, because the particles never fully hydrate in the time available.

Swapping fine into a coarse application produces a paste that thickens too fast and can go gluey, since all the starch releases at once.

Matching the grind first and treating the name second gets a usable result in almost every case, which is why the bag's description is worth reading past the front label.