We will make only brief reference to instant oatmeal, which, according to package directions, needs only a few seconds in the microwave or a dousing of boiling water. Such pseudo-porridge has only a passing resemblance to the real thing, forming a soft and smooth paste without the flavor or textural distinction that a true oatmeal lover would insist on.
The key distinction of oatmeal is whether it is made of processed or unprocessed oats. Unprocessed oatmeals have more oat bran than the processed ones. Oat bran has received attention lately because of its ability to absorb dietary cholesterol and remove it from the digestive tract before it is absorbed into the blood stream. Unprocessed oatmeals can provide substantial oat bran without adding the calories and cholesterol that have become problematic in other oat-bran products, like muffins and breads.
All the mass-market American oatmeals are made from rolled oats. These oats are cleaned, graded and pearled - a process that removes the husk from the oat grain, steam-softens it, then flattens it between heavy metal rollers spinning at super speed.
Oats processed in this way lose some protein, bran and B vitamins, but have a longer shelf life than more natural oatmeals, because enzymes in the grain are destroyed by the heat of steaming and rolling. These enzymes, present in unprocessed oatmeals, cause the oil in the oat germ to go rancid once the grain is exposed to air. Hence, unprocessed oatmeals are sold in vacuum-packed tins rather than the cardboard packaging of products of rolled oats.
