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Onions are from the Allium genus.  Other close relatives include garlic, shallots, leeks, chives and scallions.  Studies show that eating lots of allium vegetables may help reduce LDL cholesterol and increase the good HDL cholesterol.  They also contain phytochemicals such as quercitin and phenolic compounds which may reduce the risk of cancer and heart disease.

Onions add more than just flavour to your meal. They are low in calories (30 kcal per ½ cup), they are a good source of vitamin C (10% DV) and a souce of fibre (1.4g/1/2 cup), B6, folate, iron, potassium and manganene.

Buying Onions:

When choosing onions, pick clean, firm, well-shaped onions with no openings at the neck and that have crisp, dry skins.  They should have little or no scent.  Any sign of sprouting or mold means the onion is past its prime. Older onions also tend to have soft spots, with moisture around the neck and dark patches, all of which indicate decay. Scallions should have green, fresh looking tops that are crisp but tender. The base should be whitish. Once again, any sign of wilting or yellowing is not a good sign.

Storing Onions:

Onions should be stored at room temperature, away from bright light, and with good ventilation. Ideally, place them in a wire basket or perforated bowl to allow maximum airflow, especially if the basket or bowl has a raised base or can be suspended to allow air flow underneath. Onions with more pungent flavours, such as yellow onion, last longer in storage than the sweeter white onions, since the compounds that incur the taste also prevent spoilage. However, onions should never be stored with potatoes, as they will absorb their moisture and ethylene gas, causing them to spoil more readily.

Once cut, onions should be wrapped tightly in plastic or placed in a sealed container. They should be used within a day or two, as onions oxidize, and the oxidation process tends to deplete nutrient content quickly. Cooked onions will best maintain their taste in an airtight container where they can be kept for a few days. Don’t ever keep cooked onions in any metal containers, as this can cause discoloration. Peeled and chopped onions can be frozen (without first being blanched), but this process will cause them to lose some of their flavor and texture.

Preparing Onions:

A large deterrent in the consumption of onions is often the preparation. As onions are chopped, cells break and a reaction occurs that releases sulfur compounds and these compounds may irritate the eyes and cause tearing.  Cutting onions under running water can prevent this gas from forming and reaching your eyes, and using a sharp knife reduces cell breakage, also reducing the chances of bleary eyes. Chilling your onion in the refrigerator for 30 minutes before cutting can also reduce the enzyme action and thus tearing.

Cutting onions:

Peel off the skin and cut off the tip (not the root end as this end has more sulfur compounds.  Cut the onion in half and then slice even cuts up to but not through the root.  Then slice horizontally making the desired dice you need.  Cut off the tough root at the end.

Eating Onions:

Raw: in salads, salsa and burgers

Sauteed with mushrooms, in stir fry or for pasta sauces

Caramelized and served with cheeses

Roasted with root vegetables

Marinated or stewed.

They are used in virtually every type of cuisine from Indian and French.

Average onion consumption is 13.5lbs of onions per person across the world.