The red onion is not as common as the white or yellow onion. It has a milder flavor that is slightly sweeter than that of yellow onion. Its flavor makes it ideal for salads and crudités because it is much better raw.
Red onions, also known as purple onions, can be bought from the vegetable section of supermarkets and fruit and vegetable dealers or suppliers.
Cooking red onions is not recommended, because they lose a great deal of their flavor and become bland. Red onions can be stewed and used as a sweet relish for spreading on toast.
Red onions are mainly eaten raw. They have a mild, slightly sweet flavor that goes very well with crudités. A few slices can also be served in a burger or sprinkled over a pizza. Besides its good flavor, its color makes it suitable for enlivening the appearance of many dishes.
A red onion will keep for several days in the vegetable crisper drawer of the refrigerator.
Red onions have more nutritional properties than other types of onions, which are already well known for being natural health foods. All onions contain vitamins and minerals; they are one of the best sources of selenium (a significant antioxidant in the fight against aging) in our diet. Red onions have some of the highest levels of antioxidants, which reinforce their benefits to our cardiovascular system. They inhibit (especially when fresh) platelet aggregation, resulting in a lower risk of blood clots.
There are several varieties of red onion. Among these are Red Brunswick, resembling a fig in shape; Flat of Italy; Doux de Toulouse (quite rare); and Simiane (Rossa Lunga di Firenze), with a dark red, very large, and elongated bulb. The Rosé de Roscoff, which is pinky red, comes from Brittany and has Protected Designation of Origin (PDO) status.