Rolled oats are probably the most famous oat product. Oats (Avena sativa) are in the family of grasses, and the valuable nutrients that they contain make them one of the most nutritious grains.
How long do you have to soak rolled oats for? Rolled oats are a key ingredient in many muesli mixes. You can soak oats in tap water overnight or pour milk alternatives or freshly squeezed orange juice (see Erb Muesli) directly over them, leave the oats to stand for a short time, and eat.
Porridge is traditionally made from rolled oats cooked with milk or milk alternatives. Milk alternatives include oat milk, rice milk, almond milk, and soy milk. In some countries such as Germany, porridge is sweetened. In Scandinavia, porridge cooked with water is known as havregrøt and is salted or lightly sweetened. Rolled oats that are baked with honey and nuts are called granola. Oatmeal gruel is a thin, watery porridge strained from oats that have been boiled in water. It is often given to babies or sick people, as it is easy to digest while also supposedly strengthening the digestive system.
Rolled oats not only taste good for breakfast, but they are also a great addition to spicy dishes. Baked or fried patties made from rolled oats and vegetables or potatoes are delicious. For dessert, you can make a variety of delicious rolled oats recipes including cookies, waffles, muffins, donuts, and chocolates. The lack of gluten in oats makes oatmeal less suitable for baking bread but you can make scones with oatmeal or oatmeal mixed with another type of flour — especially if you want to give your scones a special flavor!
Rolled oats are often combined with lots of sugar and fat, making the oats unhealthy. Remember to eat a balanced diet and always reduce your intake of salt, sugar, and fat.
Recipe for Vegan Porridge:
For the basic recipe (for 4 servings) you need: 200 g rolled oats (organic), 600 mL water, 1 pinch of salt, and 150 mL plant milk — almond milk works particularly well for this recipe. Bring the rolled oats to a boil in salted water in a large saucepan. After boiling, reduce the heat, let the mixture simmer for 5–10 minutes, and stir regularly. When the oats swell up and the mixture develops a creamy consistency, the porridge is ready to eat. Remove from the heat, stir in the almond milk, and sweeten and season the porridge to taste (e.g., with cinnamon, vanilla, turmeric, maple syrup, agave syrup, or chopped dates). You can also garnish the porridge with a variety of toppings, for example, nuts, seeds, banana slices, fresh (or thawed) berries, pumpkin puree, or other fruits.
You can try our following recipes: Oat Dessert Balls Made with Pulp (e.g., carrot), Lemon Poppy Seed Porridge with Rolled Oats and Lemon, Sunday Brunch Rolls (Raw) with Almond Pulp and Flaxseed, and Fruit Balls with Raisins, Nuts, and Rolled Oats.
Purchasing — where to shop?
Are rolled oats heated during processing? Yes, rolled oats are usually heated (kiln dried) and therefore cannot be considered a raw food. If a raw diet is important to you, you can also find raw oats (oat groats) made from sprouted oats. The sprouting process makes the rolled oats more digestible and increases the bioavailability of their valuable nutrients. Oats are heated to increase their shelf life.
When purchasing, it is helpful to be able to distinguish between common oats (Avena sativa) and hull-less oats (Avena nuda), also known as naked oats. Hulless oats have hulls that separate easily from the grain when threshed, meaning that they don’t need to undergo a dehulling process. Hulless oats are more difficult to find as they are more susceptible to fungal diseases and produce smaller yields. In common oats (Avena sativa), the hull is firmly attached to the oat, requiring complex dehulling procedures. Depending on the hulling process16, the oats are pretreated with heat to make the dehulling easier (bottom runner hulling process). On the other hand, when a peeler centrifuge is used, heat is only applied after dehulling. This “kilning” (drying) process is carried out on both conventional and organic oats. Not only does it destroy the oats’ sprouting capacities1, but valuable amino acids (e.g., lysine) are also lost in the process.
Can you eat raw oats? In principle you can — and you can also buy oats that have not been heating treated. If you are looking for raw, sprouted oats, it is best to look in organic food stores, health food stores, and on the Internet. If the term “gentle production” appears on the packet, it does not necessarily mean that the temperature has been kept below 42 °C.
You can find conventional (not raw) rolled oats in major supermarkets including Walmart, Whole Foods Markets, Kroger, and Safeway (United States); Extra Foods, Metro, and Freshmart (Canada); Asda, Sainsbury’s, Tesco, Aldi, and Lidl (Great Britain); and Woolworths, Coles, Aldi, and Harris Farm (Australia).
You can also buy oat groats and make rolled oats yourself — look for “naked oats.” In organic shops, you can also find naked or hull-less oats by looking for “sproutable oats” and “raw oats.” You may also be able to find these in package-free shops. If a package is just labeled “oats,” these are almost always common oats that are very rarely raw.1 If possible, try to buy organic, regionally grown oats and roll them yourself. This is because of additives found in conventionally processed rolled oats. In 2015, Ökotest detected pesticides, glyphosate, and mineral oil in every second sample of conventional rolled oats.2
Rolled oats are often divided into three categories:
- Coarse rolled oats: rolled whole oats that don’t undergo any further processing and can be cooked and eaten as old-fashioned oatmeal
- Fine rolled oats: smaller oat groats are used to make these rolled oats; they absorb water more easily
- Quick-cooking oats (instant oats): rolled oats that have been rolled into small flakes. They are basically powdered oats and take almost no time to cook. They are often used to make oatmeal for babies or for those following a special diet.
There are two types of wild oats: the common wild oat (Avena fatua L.) and the hairy brome (Bromus ramosus). Common wild oats are very closely related to cultivated oats (Avena sativa), meaning that they can be crossbred. Wild oats may negatively affect oat production as they tend to reduce the yield.4
Rolled oats are only edible (for humans) once they have been hulled. After harvesting, coarse dirt, other grains and kernels, and the straw parts of the plant are separated in the mill, and the kernels are sieved and sorted according to size. The oat kernels are then dried at approximately 90–120 °C bypassing the kernels through hot pipes. Drying reduces their moisture content and deactivates the fat-splitting enzymes they contain. This significantly reduces the risk of the oat kernels and rolled oats becoming rancid, and is ideal for transporting and trading oats as they gain a longer shelf life. Furthermore, this treatment process partially dissolves the starch contained in oats, making the oats more digestible. Kilning oats also change their taste, making them nuttier.5 Many manufacturers believe that oats taste bitter when they have not undergone heating. However, this is more likely to be true of hull-less oats, which tend to contain more bittering agents.
Kilning also makes the dehulling process easier16 (dehulling involves the removal of the outer hull, the husk, and the grain).
Kiln drying is unnecessary if you use a centrifugal peeler to dehull oats. For this, the oats are thrown into a baffle ring, where the husks are separated from the rest of the oat. The rest of the grain remains intact, including the endosperm, the outer layers, and the germ. Lighter husks are removed using a suction fan. It is only then that the oats undergo kilning.16 Before oats are rolled, they must be steamed with hot water vapor to improve their elasticity. After rolling, the flakes are dried again.3,5,6
Oats are considered whole grains as they contain an endosperm, germ, and bran.3
Store-bought rolled oats should be stored in a dry and dark place, ideally in an airtight container. Rolled oats that have undergone heat treatment have a considerably longer shelf life. Rolled oats made from sproutable oats or hull-less oats that have been specially rolled do not last very long, so you should always prepare them freshly. If the hull is destroyed, the rolled oats develop a rancid taste after a few weeks because they contain a lot of healthy, unsaturated fatty acids.
Nutrients — nutritional information — calories:
A serving of 100 g rolled oats contains approximately 371 calories. Oats are a very nutritious grain compared to other grains common in the United States and Central Europe. Protein makes up 13 % of oats, being mostly essential amino acids, while high contents of fat (7 %) and carbohydrates (69 %) mean that oats provide a lot of energy. The protein found in oats is much more nutritious than the protein found in wheat.7 Rolled oats contain high amounts of manganese, phosphorus, magnesium, potassium, calcium, zinc, and iron. Other nutrients found in oats include vitamins such as thiamine (vitamin B1), folate (folic acid), pantothenic acid (B5), and riboflavin (B2). For more detailed nutritional information, please refer to the table below the text.8
Oats also contain phytosterols, alkaloids, avenanthramides (phytonutrients), silicic acid, and linoleic acid. Oats also contain approximately 4.5 % of β-Glucans, a soluble dietary fiber.9
If you combine rolled oats with a source of vitamin C, you can increase the amount of iron you absorb from oats since ascorbic acid enables the conversion of Fe3+ to Fe2+, which the blood cells absorb.
Health aspects — effects:
Why are rolled oats so healthy? Rolled oats are healthy and inexpensive, and can serve as a superfood not only for athletes but also for people with a more moderate lifestyle. The essential amino acids contained in rolled oats help to build up muscles and support the metabolism in breaking down fat. This makes rolled oats a particularly healthy source of calories for bodybuilders.
Beta-glucans (β-glucans) are unbranched polysaccharides and are a form of soluble dietary fiber. Beta-glucans are mainly found in the outer layer of the endosperm (aleurone and subaleurone layer). They make up two-thirds of the soluble dietary fibers in oats. The physical and chemical properties of these beta-glucans have a positive influence on cholesterol and blood sugar levels. Beta-glucans bind bile acid, which leads to the excretion of cholesterol and thus reduces LDL cholesterol levels and total cholesterol levels.
Are rolled oats good for diabetics? Beta-glucans increase the viscosity of food in the stomach and intestines, slowing down gastric emptying. This slowing down of digestion helps you to feel fuller for longer, which is beneficial for type 2 diabetics as well as for people with healthy blood sugar levels.10 Scientific studies show that following a high-fiber diet reduces the risk of high blood pressure, lipid metabolism disorders, and coronary heart disease.11 Furthermore, β-glucans have a calming and regulating effect on the digestive organs.10 Compared to oat bran, wheat bran contains mainly water-insoluble fiber. This type of fiber helps to lower blood glucose levels but does not influence the blood lipid content.12
Can eating rolled oats help you to lose weight? Rolled oats help you to feel full for longer, helping to ward off hunger. They are therefore an excellent addition to the diet of people who want to lose weight in a healthy manner and maintain a healthy weight. Many grains contain phytic acid, which often has a negative reputation. This is because phytic acid binds minerals such as iron, zinc, calcium, and magnesium in the stomach and gastrointestinal tract, preventing them from being absorbed. By delaying the breakdown of starch in the body, phytic acid also regulates blood sugar concentration. According to Wikipedia, oats have between 0.42 and 1.16 g phytic acid/100 g.
Rolled oats contain antioxidants that can lower blood pressure and counteract inflammation and itchy skin.13 Furthermore, introducing rolled oats into children’s diets at a young age is believed to reduce the risk of asthma.14
Dangers — intolerances — side effects:
Oats are actually gluten-free. However, commercially available common oats (Avena sativa) are usually contaminated with other gluten-containing grains such as wheat, barley, spelt, and/or rye. Conventional oat products are therefore unsuitable for people with celiac disease. Gluten-free oats have a gluten content of fewer than 20 parts per million and are identifiable by the gluten-free symbol: the Crossed Grain.15 Various studies show that people with celiac disease can cope well with small amounts of oats. Many people with allergies to gluten and celiac disease are affected by gliadin but not by other types of gluten (e.g., avenaline in oats). If you are affected by celiac disease, it is essential that you buy oats that are labeled gluten-free.9 Some people cannot tolerate gluten-free oats either: it is important to test this with a doctor.
Traditional medicine — naturopathy:
Oatmeal is a proven household remedy for gastrointestinal problems. In case of constipation, eat rolled oats or oat bran with a sufficient amount of liquid to help ease constipation. Older people, in particular, swear by porridge as an easily digestible form of oats.
Occurrence — origin:
Oats were first cultivated in Switzerland during the Bronze Age. It was not until the nineteenth century that potatoes and wheat replaced oats as a staple food. Today, Russia, Canada, Australia, Poland, China, Finland, the United Kingdom, Spain, Argentina, and the United States are the top 10 producers of oats.9
Cultivation and harvest:
Oats are an annual summer crop produced and prefer a moderate climate with high rates of rainfall. They do not require a special type of soil. Oats are also known as a “nurse crop” because many pests do not reproduce in them. Oats forms in a multi-branched panicle, not in an ear like wheat.
Rolled oats are usually made from the common oat (Avena sativa), and more rarely from hull-less oats (Avena nuda). Both types of oat belong to the genus Avena and are sweet grasses. Common oats are cultivated as a grain and are colloquially referred to as oats. There are approximately 25 Avena species that spread from Northwest Africa and Spain through the Mediterranean region to the Near East.
Instant oats are used to make oat milk: this substitute for dairy milk is good for people who suffer from lactose intolerance or who want to eat a vegan diet.
Literature — sources:
Many researchers do not believe that Wikipedia is an authoritative source. One reason for this is that the information about literature cited and authors is often missing or unreliable. Our pictograms for nutritional values provide also information on calories (kcal).
- Zentrum-der-Gesundheit.de Qualität von Hafer erkennen.
- Ökotest.de Haferflocken im Test. 2015.
- Wikipedia Haferflocken.
- Wikipedia Flughafer.
- Alleskoerner.de Hafer Verarbeitung.
- Einfach-clever-essen.de Vom Haferkorn zur Haferflocke.
- Demeter.de Hafer.
- USDA United States Department of Agriculture.
- Wikipedia Saat-Hafer.
- Ernährungs-umschau.de Beta-Glucan aus Hafer.
- Daou C, Zhang H. Oat Beta‐Glucan: Its Role in Health Promotion and Prevention of Diseases. Online Library. 2012. doi:10.1111/ j1541-4337.2012.00189.x
- Schmandke H. Blutglucose- und -lipidsenkende Wirkung von Phytinsäure. Ernährungs Umschau. 2007;5.
- Sur R, Nigam A, Grote D, et al. Avenanthramides, polyphenols from oats, exhibit anti-inflammatory, and anti-itch activity. PubMed Arch Dermatol Res. 2008;300(10). DOI: 10.1007/ s00403-008-0858-x.
- Fiocchi A, Assa'ad A, Bahna S, et al. Food allergy and the introduction of solid foods to infants: a consensus document. Adverse Reactions to Foods Committee, American College of Allergy, Asthma, and Immunology. PubMed Ann Allergy Asthma Immunol. 2006;97(1).
- IG Zöliakie der Deutschen Schweiz. Hafer in der glutenfreien Ernährung. 2018.
- Heiss, R. (Hrsg.). Lebensmitteltechnologie: Biotechnologische, chemische, mechanische und thermische Verfahren der Lebensmittelverarbeitung. Springer; 1996: 149ff.