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Healthy and Sustainable Food

Onions

DATES AVAILABLE:

New England: Mid-July through October; Storage: 5-8 months
Mid-Atlantic: Early June through mid-October; Storage: 5-8 months

BRIEF DESCRIPTION:

The onion (Allium cepa, Liliaceae), is one of the oldest and hardiest garden vegetable plants.  Formed underground as a bulb at the base of leafless stalks, onions are surrounded by a thin, paper-like skin and vary in size, shape, color (white, yellow, red) and pungency. A sulfur compound gives onions their pungency and is responsible for their smell as well as their ability to cause the eyes to tear. Usually categorized by color,  taste or use, onions can be grown directly from seeds, sets (previous year’s onions) or seed transplants.

VARIETIES:

As mentioned, onions may be classified by color, taste or use; in cooking, onions are often referred to as either “sweet” or “storage.” Sweet onions are higher in water and sugar content, have a sweeter and milder flavor and are eaten closer to time of harvest, either raw or lightly cooked. Warmer climates are more hospitable to growing sweet onions. Storage onions tend to be more pungent, last longer in storage and are often preferred cooked prior to consumption.

Red onions generally have a fairly sweet taste and are eaten raw or lightly cooked, particularly grilled. Used to add color to various dishes, sweeter-tasting red onion varieties found at farmers’ markets include New York State Redman, Braunsweiger, Benny’s Red and Mambo.  Varieties that hold up better in storage include Southport Red Globe, Redwing and Mars (moderate storage life).

White onions are popular for cooking because they have a clean, tangy flavor.  Often used in Hispanic dishes, varieties that may appear at farmers’ markets include Southport White Globe, White Portugal, and White Superstar. White onions may be more vulnerable to mold than other varieties, therefore proper storage in a dry, well-ventilated place is very important.

Yellow onions are the most common type of onions grown in the United States overall. Considered the generic onion, a yellow onion is what most people use when preparing a recipe. Yellow onions tend to be pungent (many find them too pungent to eat raw) due to high sulfur content and have complex flavors. When cooked, they become sweeter and milder. Varieties you may find at local markets include Ebenezer, Stuttgart/Stuttgarter, Yellow Super Star, Copra, Corona, Viceroy, Candy, Norstar, Arsenal, and Hustler.

Spanish onions are similar to yellow onions but are larger and sweeter. 

Shallots, also Allium cepa, are small onions with a more delicate, sweet flavor than other cooking onions. Shallots vary in taste, shape and color,  grow in clusters and are harvested in mid-summer and early fall. At farmers’ markets you may see red varieties such as Holland Red, Red Sun, and Prisma, which stores well. A common white variety is Ambition. Popular yellow varieties you may see are Golden and Bonilla. Matador is a common, popular brown variety that stores well. 

USING ONIONS:

At markets, select onions that are round and firm, with tight skin and good color. Avoid those that have sprouted or have an unpleasant or atypical odor, or that have green or moldy blemishes.

Onions are extremely versatile and typically consumed raw or cooked. They can be incorporated into a multitude of dishes such as salads, sandwiches, soups, pizzas, stews, casseroles and breads. Often a base ingredient for many dressings, sauces and soups, onions are also commonly included in appetizers, entrées or side dishes, but rarely eaten alone, with the possible exceptions of onion rings or when pickled. Onions can be broiled, boiled, baked, creamed, steamed, fried, sautéed, stir-fried, braised, grilled or roasted.  For a stronger taste, using raw or lightly cooked onions is ideal.

Shallots are often finely chopped and similarly included in many dishes.  A common ingredient in French sauces, shallots are also mild enough to be cooked and eaten alone.

NUTRITIONAL INFORMATION:

One cup of chopped onions provides about 65 calories, is high in vitamin C, is a good source of fiber and has substantial potassium. Onions also contain the flavanoid quercitin, an antioxidant thought to benefit the intestinal tract. They also contain anti-inflammatory components called isothiocyanates and sulfur compounds believed to be beneficial in preventing chronic disease.

STORAGE:

General: Onions can be stored for several months in a cool, dry, well-ventilated place.  To avoid tearing during cutting, cut under running water or chill in the refrigerator first. Refrigerate cut onions in an airtight container to avoid transfer of flavors and smell to other foods.

Drying: Onions can be dried.