The Onion's Flavor, in one form or another "Blends into almost everything in the meal except the dessert." - Julia Child
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Behold, the Onion (Allium Cepa). It is a member of the Allium Family (Shallots, Leeks, Green Onions, Garlic, etc.) and is beloved and loathed—likely in equal parts—all across the globe. Onions emit a chemical substance when chopped that can cause tears to roll, hacking coughs, fits of sneezing and more because when the Onion’s cell walls are broken by the blade, Amino acids called sulfoxides mix and form sulfenic acids. These acids create a gas called syn-propanethial-S-oxide that are released into the air, and once they reach the eyes, they bind to sensory neurons. This is what causes the stinging sensation and causes the tear glands to produce tears to dilute and flush out the irritant.

Despite the side effects, Onions are still one of the most common ingredients in savory dishes all over the world. Onions are available in numerous varieties ranging from Mild to Sweet to Pungent in flavor. See Varieties below.


Onions are a Fall Seasonal Vegetable and a Winter Seasonal Vegetable, yet they are also grown and harvested all year round.


Onions are available all year long, at almost any grocery store.


Onions are grown in a 5-6 month cycle and are grown from seeds or they are transplanted.


Onions are grown commercially in over 20 states nationwide. The most popular type of Onion grown in the United States is the Yellow Onion, which accounts for a whopping 87% of all production.

Most onions are harvested using machinery for “storage” (white, yellow, red) onions and hand harvested for fresh onions (green etc.).


Yellow Onions, Red Onions and White Onions, are all Bulb Onions, which come in many sizes ranging from the Super Colossal Onion at 4 ½ inches, or more, in diameter to the Creamer Onion that is under 1 inch in diameter.

Other familiar Onions include: Bermuda Onions, Shallots, Green Onions, Spanish Onions, Pearl Onions, Vidalia Onions, Maui Onions, Cipollini Onions.


When purchasing onions, look for dry outer skins that are free of spots or blemishes. The onion should be heavy for its size with no discernible scent.


Store whole onions in a dry, cool, well-ventilated place. Storing in a plastic bag is not a good idea as Onions need strong air circulation. If you happen to have an old pair of pantyhose around, they can come in handy to store Onions and extend their shelf life. Tie a knot between each onion. Onions will last 2-4 weeks at room temperature.

Whole peeled Onions should be properly refrigerated at 40°F or below, out of The Food Danger Zone. Chopped or sliced onions can be stored in a sealed, air-tight container in your refrigerator at the proper temperature of 40°F or below for 7 to 10 days.

For pre-cut fresh or frozen products, always use and follow manufactures "use by" dates.

Culinary Uses

Onions have a pungent, sweet flavor and a paper-like, firm layered texture. Onions are used for their flavor and for their texture in Baking, Roasting, Flame Roasting, Sautés, Pan Frying, Sweating, Deep Frying, Grilling, and Stir Frying. Onions can also be Boiled, Braised, Stewed, Steamed, Simmered, made into Stocks or even eaten raw. As a principal component of the Mirepoix, Onions are also the base, of the base, of many of the world’s classical dishes.

To minimize crying while chopping raw onions chill the onion for 30 minutes and then cut off the top and peel the outer layers, leaving the root whole. You can also mitigate the tears by chopping Onions near running water, not under but near.

Smart Kitchen has a number of exercises that utilize Onions including: Caramelize Onions, Peeling Onions, Dice an Onion, Onion Brulee, Van Dyke an Onion, White Mirepoix, Brown Mirepoix, Sweating Onions and more.

Portion Size

Allow 1-2 oz of Onions per person.


Chives, Leeks, Shallots

Nutritional Value USDA
Amount Per 100g
Calories 40
%Daily Value*
Total Fat 0g
Saturated Fat 0g
Polyunsaturated Fat 0g
Monounsaturated Fat 0g
Cholesterol 0mg
Sodium 4mg
Potassium 146mg
Total Carbohydrate 9g
Dietary Fiber 1g
Sugars 4g
Protein 1g
* Percent Daily Values are based on a 2,000 calorie diet. Your Daily Values may be higher or lower depending on your calorie needs.

Onions are high in Vitamin C and Dietary Fiber as well as other nutrients, additionally they are very low in calories and fat free.

Gluten Free


Low Fat


Low Calorie