Where Are Thick and Quick Oats Used?

Rolled oats are made by steaming oat groats to soften them, then flattening them between rollers. If the groat is flattened whole, it becomes a thick rolled oat; if it is broken first and then flattened, it becomes a quick oat. The only difference is the size of the piece, but this difference makes the two products behave like two separate ingredients in the kitchen. That is why seeing only the word “oats” on the package is not enough; check the size of the pieces too. Substituting these two oat types for each other in the same recipe can give a result that is far from expected.

Thick oats absorb water slowly and hold their shape as they cook. In oatmeal, you can feel each oat separately; they leave a chewy texture in your mouth. Cook them in milk or water for a few minutes, then let them rest for a while after removing them from the heat. Thick oats are also used in overnight recipes because they do not fall apart, even after soaking in water for hours. Stir thick oats only occasionally as they cook; constant stirring breaks the flakes and ruins their texture.

Quick oats do the opposite. Their large surface area lets them absorb water quickly and gives them a creamy, smooth texture in a short time; pouring them into boiling milk and letting them sit for a few minutes is often enough. This speed is an advantage, but it is a problem if you want a chunky texture. Oatmeal made with quick oats is always soft and does not feel grainy. This speed is especially convenient for breakfasts made in a hurry in the morning. On the other hand, for someone who wants a chunky texture, this speed is a limitation rather than a benefit.

The difference is even clearer in baked recipes. Use thick oats in cookies and granola; the flakes stay whole as they bake and add both visual appeal and crunch. If you use quick oats in the same recipe, the flakes blend into the dough and disappear, giving the cookies a floury texture. By contrast, if you need a binder for meatballs, quick oats are more suitable because they absorb water quickly and bring the mixture together. When a recipe calls for quick oats, you can pulse thick oats briefly in a food processor to make them finer, but you cannot do the reverse.

There is a third type: steel-cut oats. Because the groat is only cut and not flattened, this type takes the longest to cook and has the most pronounced texture; it needs a cooking time of up to half an hour. The three types cannot be substituted measure for measure because they absorb water at different rates. Store all three the same way: in a closed jar in a cool, dry cupboard. Oats have a relatively high fat content, so a package kept for a long time may develop a bitter smell. Transferring opened oats to a jar slows their exposure to both moisture and odors.