The yellow onion is the most common onion variety. It has a stronger, more complex flavor than white onions and is frequently used in cooked dishes. Yellow onions are divided into three categories: sweet, mild, and storage, with each variety having its own set of characteristics.
Bulb onions are usually classified into three color groups. The skin and flesh of white onions are both white. Red onions have a deep red skin and a white flesh with hints of red in between layers, and are also known as purple onions. The skin of the yellow onion, also known as the brown onion, is flaky and dark yellow or light brown, with white flesh.
The yellow onion is used in the majority of recipes by most cooks. Yellow onion varieties account for roughly 87 percent of the onion crop in the United States, while red onions account for only 8% and white onions for only 5%. Yellow onions are available all year, but some varieties are only available during specific seasons. During the spring and summer, sweet and mild yellow onions grow, but storage varieties grow during the last summer, autumn, winter, and early spring.
Yellow onions contain more sulfur than other onion types, giving them a more complex flavor. When the onion is cooked, the flavor intensifies. Cooking a yellow onion caramelizes it, bringing out its sweetness, but raw yellow onions can be quite pungent.
When sauteed or grilled, yellow onions come in a variety of colors. The onions should be cooked over low to medium heat for these light cooking methods, as quick, high heat can cause the onion to become bitter. Another advantage of cooking the onion slowly over low heat is that the flavor is sweeter than if it is cooked quickly over high heat.
Sweet onions are the most commonly eaten raw of the various yellow onion varieties, followed by mild onions. Sweet onions have a mild flavor and a short aftertaste. Mild yellow onions, also known as fresh onions, have a slightly stronger flavor that lingers in the mouth. The storage onion is the most pungent, and it is not recommended to eat them raw. However, most cooks prefer storage onions for recipes that require a long cooking time because the sulfur content is higher in this variety and has the strongest chemical reaction when cooked.
However, because sulfur is also what makes people cry when they cut onions, yellow onions produce more tears than other bulb varieties. Cooks can mitigate this effect by rinsing the onion in cold water to remove excess sulfur. If this does not work, a person can try cutting an onion while using a fan to disperse the irritant and send it away from the eyes.
When purchasing yellow onions, consumers should look for firm onions with a dry, paper-thin skin. Yellow onions with a moist skin, as well as those that are soft and “give” when pressed, have gone bad and will develop mold spots in a matter of days or hours. Whole onions should be kept in a cool, dry place. Yellow onions can be stored in a sealed container for up to a week after being chopped or sliced.