Don't Forget the Lowly Onion

Good flavors come in threes, and onions are often used with garlic and olive oil as an aromatic and flavorful base for many traditional savory dishes. If it isn't dessert, there's probably an onion in it somewhere, and using onions to advantage can be an art.

Onion Facts and Background

Onions (Allium cepa) are biennial plants with edible bulbs. They are related to the lily, and from their origins in Asia have become common throughout the world. One of the first cultivated plants, the onion is related to garlic, shallots, and chives. Its sharp flavor comes from a volatile oil in the meat of the onion that contains sulfur compounds. These sulfur compounds also help to create an enzyme that causes you to tear up when cutting onions, which is probably one of the plants defenses against predators.

How to Choose Onions

Look for onions that have papery outer skins and feel heavy when you hold them in your palm. Onions should be juicy, and heavier onions will be juicier onions. Whole onions should never have a strong smell, a sure sign that the skin has been torn or bruised. Avoid any onions that have started to sprout. Young onions are the sweetest, and sprouting is a sign of age. Sprouting also robs the onion of its juice.

Storing Onions

• Storing Whole Onions: Onions will keep for up to three months in your pantry, basement or garage if you observe three rules: Keep it dry, dark and cool. Airflow is also important; that's the reason onions are sold in mesh bags. Turn them once in a while. This will help extend their life.
  
  Never store whole onions in plastic grocery bags. Plastic will lock in moisture and gasses, prematurely ageing the onion.
  
  Don't store onions with potatoes. Potatoes and onions kept together will spoil much faster. Their combined gasses and the moisture released by the potatoes are a terrible environment for either vegetable. Don't keep uncut onions in the refrigerator. It's too cold. Exceptions to this are scallions and some of the sweet onion varieties.

• Storing Cut Onions: After cutting, wrap onions tightly and place them in the vegetable bin of your refrigerator. They will keep there for a week or so. To avoid contaminating your other refrigerated foods with onion odor, be sure to seal the wrap well, or place the wrapped onion in a sealed plastic bag.

Saving Onion Parts

Don't throw out the top, paper or outer skin of the onion. Place it in a plastic freezer bag and freeze it for soup stock. The skins and top will help flavor your soup, and the outer skin (parchment) will give your stock a nice golden-brown color.

Growing Onions

Onions are easy to grow in the garden in light, sandy soil. They can be harvested young for their shoots, or later for their bulbs. Give them a sunny spot and plenty of room to spread out.

No Tears Onions

Although science is working on developing no-tears onions, for now we'll just have to rely on the tried and true methods of cutting onions under running water or placing them in the refrigerator for an hour before cutting.

Cutting Onions

Cutting round vegetables on a flat cutting board can be a challenge. To avoid injury, cut onions in half and place the flat side on the countertop before slicing or chopping. This will make the process easier and safer.

Preparing Onions

Onions release sugars as they cook, so cooking enhances an onion's flavor. The process also makes the taste less pungent.

When cooking onions, always remember to monitor the heat closely to avoid charring. Burnt onions are bitter and unsightly. Lower heat and regular stirring is a good way to dissipate the escaping moisture in the onion and cook it evenly
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Avoiding Onion Breath and Smelly Fingers

Onion releases oils when eaten, which leads to onion breath. This can be camouflaged with mints, parsley, cloves or seeds like fennel, but basically it's just going to have to dissipate in its own time.

The problem with stinky fingers from handling onions or garlic is similar. The onion oil is absorbed into your skin and lingers for a while. To minimize the absorption, rub olive oil on your hands before handling onions. This will create a barrier and limit the amount of onion oil that's absorbed. If you can still smell onion on your hands, a lemon juice rinse will help, as will rubbing salt or cornstarch on your palms and fingers.

Onion Varieties

Yellow cooking onions aren't the only types of onions out there by any means. White onions are a good substitute for yellow onions, are easy to find and work well in cooking where high heat is required.

For use raw, purple onions and yellow sweet onions are wonderful choices. Vidalia, Walla Walla, Imperial and Maui onions are all sweet varieties. They are more fragile than yellow or even purple onions and only last a few weeks once harvested, but they offer a lot of sweet onion flavor with no heat.

Onion Tips

• Need a cup of chopped onion? A good rule of thumb is to have one large onion on hand for every cup of chopped onion in a recipe.
  
  
• Onions are high in vitamin C.
  
  
• A medium sized onion contains only about 60 calories.
  
  
• Eating onions helps lower blood pressure, reduce cholesterol and promote heart health.