Rolled vs. steel

Jun 17, 2023

Manufacturers can prepare raw oat groats in various ways to make them ready for consumption. Steel-cut oats are the least processed form, whereas rolled oats, or oat flakes, undergo more processing and flattening through steel drums.

The manufacturing process changes the qualities of oats and how a person can prepare and enjoy them. Although similar, the benefits and nutritional value differ slightly.

This article explores the nutritional value and health benefits of rolled oats and steel-cut oats. It also looks at how a person can choose between the two.

The oat, or common oat, plant Avena sativa is a cereal grain people grow for its seeds. They harvest and process oats to various degrees, creating different oat products.

The outer hull of the oat is inedible, and so all processes involve removing the groats, or inner kernels, from the whole oats. Steel-cut oats and rolled oats are two processed forms of these groats.

Steel-cut oats, also known as Irish or coarse oats, are the least processed form. Steel-cut oat processing involves chopping whole groats into smaller pieces using steel blades.

The resulting oats take longer to cook. They also have a chewy consistency and a more robust flavor than other oats, such as quick oatmeal.

To make rolled oats, manufacturers steam the oats, then flatten them using large disks or drums. The oats break apart, so they become softer and can absorb water more readily. The processed oats are quicker to cook, with a consistent texture and milder flavor.

Steel-cut and rolled oats vary from more processed oat products, such as quick oats or instant oatmeal.

Quick or instant oats often undergo other processes, such as precooking the oat and then drying it out. The resultant product has a shorter cooking time. Manufacturers of instant oat products might also add other ingredients, such as flour or sugar to give more body or flavor.

The nutritional data for both steel-cut and rolled oats are almost identical, as whole groats go through minimal processing in both versions of the cereal.

The table below presents the nutritional value of 40-gram (g) servings of steel-cut oats and rolled oats:

The mineral and nutrient contents of rolled oats match those of steel-cut oats:

Oats are simple foods that are versatile enough to fit into most people’s diets. They also have several health benefits.

Whole oats are rich in fiber, which is essential for proper functioning of the digestive system and a person’s overall health.

The specific kind of soluble fiber in oats, called beta-glucan, has many health benefits. A 2015 review notes that consuming 3 g of beta-glucan fiber each day can lower coronary heart disease risk and reduce blood cholesterol.

Beta-glucans also have potential anticancer properties, as they may reduce some causes of colon cancer.

In addition to beta-glucans, oats are a good source of various antioxidants called phenols. They may help improve cell functioning in the body and reduce inflammation.

Oats could play a role in maintaining a moderate weight. According to a 2017 review, one observational study found that participants who ate oatmeal had a reduced risk of obesity.

Both short- and long-term intake of oats helps reduce weight in people with overweight and type 2 diabetes, as well as in healthy individuals.

This effect could be the oats high fiber content that makes people feel full and reduces their calorie intake.

Whole oats are slower to digest and have lower GI scores than quicker forms of oats.

Steel-cut oats have a GI score of about 53, and rolled oats — of about 57.

Steel-cut oats may take longer to digest, reducing spikes in blood sugar. Both oat types are better choices than other forms, such as instant oats, which have a GI of about 83.

A 2017 review notes that the beta-glucan fiber in oats is partially responsible for reducing blood glucose levels and the risk of heart disease, type 2 diabetes, and cancer.

Oats are naturally gluten free and may be an ideal substitute for many products containing gluten.

However, people with gluten sensitivity or allergies should take care to find certified gluten-free oats, as flours containing gluten could contaminate oats processed in areas with other grains.

Both steel-cut and rolled oats have comparable health benefits. They also have similar nutritional profiles and contain many of the same healthy compounds and fibers.

Specific groups of people may prefer one type of oats over the other depending on their preferences and needs.

Steel-cut oats can help a person feel full for longer, which could help them manage their weight. Steel-cut oats are a complete form of oats with little processing, which means they take longer to digest than quick or rolled oats.

Authors of a 2019 review note a relationship between lower body mass index and a diet rich in whole grains, such as oats.

Steel-cut oats have a slightly lower GI score than rolled oats. People watching their blood sugar, such as those with diabetes, may want to choose lower GI foods whenever possible.

As steel-cut oats and rolled oats have similar benefits, the primary considerations for the average person choosing between the two are cooking time and texture.

Steel-cut oats undergo minimal processing, and their hard exterior can take 15–30 minutes or more to cook, depending on the method.

In contrast, the manufacturing process breaks down rolled oats further. During cooking, they allow in more liquid and cook faster, taking around 5–10 minutes before they are ready.

Texture is another factor a person may wish to consider. Steel-cut oats tend to have a firmer and chewier consistency, even when fully cooked. Rolled oats, on the other hand, have a more consistent texture, although they may still be chewier than instant or quick oats.

A person can use either form of oats to prepare breakfast cereal. However, for other uses, such as replacing rice or other grains, the texture of steel-cut oats may provide a more suitable alternative.

For foods where consistency is important, such as baked goods, rolled oats may well be a better option.

If a person is looking to curb their hunger, they may wish to consider steel-cut oats. Because of the large, unbroken pieces, steel-cut oats take longer to digest, which helps reduce appetite.

Rolled oats and steel-cut oats are two minimally processed forms of oats. They have similar nutritional values and health benefits.

Steel-cut oats may take longer to digest and therefore help a person feel full for longer. They also have a slightly lower impact on blood sugar.

The most significant differences between steel-cut oats and rolled oats may be the time it takes to cook them and their final consistency.