The moment you slice an onion, you are breaking the cell walls and releasing enzymes that are now interacting with each other and producing a volatile compound that affects your eyes. Hence the tears.
Used extensively in many cultures around the world, onions hold a special place in our hearts and kitchens. What would a dish be without onions? For one, it wouldn’t taste the same. Onions add flavor and lots of it. From soups to sauces and stews, onions are indispensable in the kitchen. Onions actually flavor more dishes than any other spice in the world. What makes this tear-inducing aromatic vegetable so unique? Let’s take a closer look.
Background
The round, baseball-sized onions we are familiar with are believed to have originated in what is now the country of Afghanistan. Set along the Ancient Silk Route, it’s no wonder onions easily traveled East and West. China is the world’s largest producer of onions. India comes in second while the United States ranks third as the world’s largest producer of the beloved bulb.
Varieties
Onions take on many forms, from scallions and shallots, to leeks and globe onions. Scallions are sold in bunches. They are sweet and mild, with the white end being a little more pungent. Shallots are oval and possess a delicate onion flavor while at the same time retaining pungency. Globe onion varietals can be yellow, red, white and brown. Leeks are long, thick and hearty. They are treasured for the exquisite flavor found in the white part of their stalks.
Uses
Every culture seems to have a preferred onion varietal. The Chinese favor scallions, while the French and Turkish prefer shallots. In Mexico, raw white or yellow onion is added to spicy salsas and guacamole. Throughout Latin America, onions are the main ingredient in sofrito, a wet seasoning used in almost every dish. In India, the brown-skinned globe onion is the most popular.
Onions can be used fresh, cooked or pickled. The French famously use them in soup while Americans favor deep-fried onion rings as an appetizer. Onions are also used in dips and tarts, and seem to have a special affinity for potato and meat dishes, as people across the world have known for centuries.
Although it seems every culture uses onions, there are exceptions. Follwers of Jainism, a religious sect in India that preaches non violence, avoid eating roots like onions beacause they believe the plant is killed when uprooted.
How to Buy
When buying globe onions, look for bulbs that are firm and dry. The color should be even and the onion should have lots of papery layers of skin. Keep away from blemished onions or those with sprouts or open necks – all signs of decay.
Storage
Dry bulb onions (including shallots) should be kept in a dark cool cupboard. They last longer this way. But scallions and leeks do better in the fridge. To keep scallions fresher longer, place in a plastic bag before you refrigerate. Leeks can be loosely stored in your refrigerator’s vegetable drawer.
Benefits
When you cook with onions, you are adding more than just flavor, you are eating for your health. Onions possess a large amount of antioxidants that have been found to combat cancer. Since they are a member of the garlic family, onions also contain allicin, an active compound that can help lower cholesterol, thin our blood and kill cancer cells. This is according to numerous studies cited in Healing Spices, a book written by Bharat B. Aggarwal, PhD and Debora Yost.