Rolled oats are probably the most famous oat product. Oats (Avena sativa) are in the family of grasses, and thanks to the valuable substances they contain, they are one of the most valuable grains.
From Wikipedia: “Rolled oats are traditionally oat groats that have been dehusked and steamed, before being rolled into flat flakes under heavy rollers and stabilized by being lightly toasted.
Rolled oats that are sold as porridge oats usually have had the tough bran removed. They have often, but not always, been lightly baked or pressure-cooked or "processed" in some fashion. Thick-rolled oats are large whole flakes, and thin-rolled oats are smaller, fragmented flakes. Oat flakes that are simply rolled whole oats without further processing can be cooked into a porridge and eaten as "old-fashioned" oats, but more highly fragmented and processed rolled oats absorb water much more easily and therefore cook faster into a porridge, so they are sometimes called "quick" or "instant" oats. Rolled oats are most often the main ingredient in granola and muesli.
Rolled oats can be further processed into coarse powder, which, when cooked, becomes a thick broth. Finer oatmeal powder is often used as baby food.”
“Whole oats are an excellent source of thiamine, iron, and dietary fiber. Whole oats are also the only source of antioxidant compounds known as avenanthramides; these are believed to have properties which help to protect the circulatory system from arteriosclerosis. Oat products also contain beta-glucan, which may help people with Type 2 diabetes control their blood glucose level, and might also help stimulate the immune system to fight off bacterial infections.”
“The oat, like other cereals, has a hard, inedible outer husk that must be removed before the grain can be eaten. After the outer husk (or chaff) has been removed from the still bran-covered oat grains, the remainder is called oat groats. Since the bran layer, though nutritious, makes the grains tough to chew and contains an enzyme that can cause the oats to go rancid, raw oat groats are often further steam-treated to soften them for a quicker cooking time (modern "quick oats") and to denature the enzymes for a longer shelf life.”
“Rolled oats can be eaten without further heating or cooking: The oats are soaked for 1-6 hours in water-based liquid, such as water or fruit juice. The soak duration depends on shape, size and pre-processing technique, saving the time and the energy spent on heating, preserving its taste, and saving its nutritional values destroyed during cooking.
Traditionally, oat groats are a whole grain that can be used as a breakfast cereal, just like the various forms of oatmeal, rolled oats and pinhead oats can be cooked to make porridge. Rolled oats are used in granola, muesli, oatcakes, and flapjacks.”
From “en.wikipedia.org/wiki/Oat”: “Oats are best grown in temperate regions. They have a lower summer heat requirement and greater tolerance of rain than other cereals, such as wheat, rye or barley, so are particularly important in areas with cool, wet summers, such as Northwest Europe and even Iceland. Oats are an annual plant, and can be planted either in autumn (for late summer harvest) or in the spring (for early autumn harvest).”
“In 2014, global production of oats was 22.7 million tonnes, led by Russia with 5.3 million tonnes or 23% of the world total. Other major producers were Canada, Poland, and Australia.”