What’s the Difference Between Types of Oatmeal?

If you're going to eat oatmeal, you might as well eat the kind not stripped of its nutrition. Especially if you're feeding it to kids. But hey, you matter too. What’s the difference between steel-cut, Scottish, Irish, rolled, quick-cooking, old-fashioned, and instant oats? Some are milled differently, while others are exactly the same but called different names.

For every type, the oats first undergo cleaning, hulling, and conditioning, which removes the outer shell (called a hull), leaving the inner kernel or oat groat. The groat is then brushed clean in scouring machines. Next, a kiln heats the groats to about 215 degrees Fahrenheit to deactivate their enzymes, which limits how the oils present in the germ can react with oxygen, making the oats stable for storage. Chelsea Lincoln, a representative from Bob’s Red Mill Natural Foods, says this is important because “oats go rancid very quickly if not stabilized.”

From there, the whole oat groats are processed differently depending on what type of oatmeal they are being made into. Lincoln says that to make steel-cut oats (also known as Irish oats), the groats are chopped up with steel blades. “This allows for a chewier oatmeal,” says Lincoln. For Scottish oats, the groats are ground into a meal, which makes a “porridge-type oat with a nice, creamy texture.” Irish and Scottish oats take about 30 minutes to cook.

Rolled (also known as old-fashioned) oats take less time to cook. The groats are softened by steaming, then run through metal rollers to flatten them. Lincoln says that Bob’s Red Mill regular rolled oats are flattened to 0.024 to 0.032 inches, while quick-cooking oats are rolled even thinner—about 0.017 to 0.022 inches—so they will cook in under five minutes. Instant oats are also rolled thin, but are then “cooked and then dried again,” says Lincoln. Just add hot water and stir.

The less processed the oats are, the more nutrition they retain. And watch for added sugars and preservatives in instant oats. The three most obvious things to make with oats are oatmeal, cookies, and bars. What might not be obvious, is how exactly to create these dishes and treats, and to create them well. Here are eight of our favorite ways.

1. Apple Oatmeal Bars


Some of us at Chowhound have made these for a casual party, and they were a hit. They're chewy, sweet, soft, and a little crunchy on top with the oat crumble. And they're easy to make with ingredients many of us keep on hand already so there's no hunting down a random ingredient at the store. Get our Apple Oatmeal Bars recipe.

2. Slow Cooker Steel-Cut Oatmeal


Toss the ingredients into your Crock-Pot right before you go to bed and wake up to some creamy, warm breakfast. Just add vanilla, nuts, and fruit — fresh or dried. Get our Slow Cooker Steel-Cut Oatmeal recipe.

3. No-Bake Oatmeal Cookies


Wait, what? Oh, yes. These are especially great during the summer, when you don't want to heat up your kitchen more than it is already. It takes 15 minutes to make, plus cooling time. These cookies taste of chocolate and peanut butter too, and we love that. Get our No-Bake Oatmeal Cookies recipe.

4. Peach Melba Pie


This is what your summer is missing: Peaches and raspberries encased in a crust and topped with an oat-brown sugar streusel. Serving this pie with a scoop of good vanilla ice cream is a must. Get our Peach Melba Pie recipe.

5. Oatzravaganza Cookies


In these cookies, coconut flakes and chopped pecans provide a pleasing texture along with their nutty, tropical sweetness. Get our Oatzravaganza Cookies recipe.

6. Overnight Oats with Summer Fruit

You don't have to cook this at all! The rolled oats absorb the milk and get soft with time. Now that's easy. Dump the ingredients in a bowl or jar the night before, refrigerate, and then take it out the next morning, top it with fresh fruit, and eat. Get our Overnight Oats with Summer Fruit recipe.


7. Blueberry Oatmeal Crumble Bars

Bob's Red Mill

Want something healthy-ish and sweet? Go for these bars, made with whole wheat pastry flour, rolled oats, and coconut sugar. There's no regular sugar in them, and you can use fresh or frozen blueberries. Get the recipe.

8. Easy Apple and Pear Crisp with Oatmeal Streusel


You know when you want pie, but you don't want to deal with making a crust? That's what crisps are for. And this oatmeal streusel's got it goin' on. Get our Easy Apple and Pear Crisp  with Oatmeal Streusel recipe.

Head image: mmgood.com

Originally written by Roxanne Webber March 21, 2008; updated by Amy Sowder June 24, 2016.

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