Red onions, are cultivars of the onion (Allium cepa) with purplish red skin and white flesh tinged with red. These onions tend to be medium to large in size and have a mild, to sweet flavor.They are often consumed raw, grilled or lightly cooked with other foods, or added as a decoration to salads. They tend to lose their colour when cooked. Red onions are available throughout the year. Red onions are high in flavonoids, and fibre, (compared to white and yellow onions). They can be stored 3 to 4 months at room temperature (Wikipedia).