Are You Using the Right Onions?
The onion is believed to be one of the earliest cultivated crops, and with the hundreds of species of onions out there, it’s obvious why that is a fact.
Onions belong to the allium family, along with shallots, garlic, leeks and chives. The onion, or some member of its family, serves as the backbone to nearly every type of cuisine. The French make mirepoix, which is a combination of onions, celery and carrots. In Cajun and creole cuisine, cooks often use the “holy trinity” of onion, bell pepper and celery. Many Spanish dishes use a base known as sofrito which is garlic, onion, tomatoes and paprika, all cooked in olive oil. The cuisine of Cantonese China relies heavily on a combination of garlic, ginger and scallions.
More Than Just Flavorful
In addition to being packed with flavor, every member of the allium family is loaded with nutrients. They can be a good source of vitamin C, vitamin B6, potassium, folate and fiber, all without adding many calories.
But it’s their sulfur compounds that give them their characteristic taste and smell. Along with these compounds are the flavonoid quercetin – it’s what gives the allium family their more unique and powerful health benefits. These compounds have been linked to a lower risk of cancer, lower risk of heart disease and stroke, improved blood sugar control and can help fight bacteria. To get the most benefit from the sulfur compounds, let fresh onions and garlic rest for a few minutes between cutting and cooking.
The Right Onion for the Job
I would argue that you can’t really use garlic or onions incorrectly. I am extremely fond of both, but there are some tips and tricks for using onions to their full potential:
- Yellow onions can be a little strong when eaten raw. Because they have a slightly higher starch content they hold up well to heat; therefore, this is the ideal all-purpose cooking onion.
- Although they are even sharper in flavor than yellow, red onions are often eaten raw. If you need to mellow the flavor try soaking the cut onions in cold water; it will make the texture even crisper but tame the flavor. Red onions are also an ideal choice for grilling and pickling.
- While their color is similar to the yellow onion, white onions have a thinner, more-papery skin. They are also known for their consistently milder flavor, making them a better choice for serving raw. All three of these varieties are cured after harvesting, so they can typically last at least a few weeks at room temperature in a dark, dry pantry.
Even More Names and Some Confusion
Now this is where things get confusing! There’s more to onions than meets the eye.
- Sweet onions, which are often named for the region where they were grown, such as Washington’s Walla Walla, Georgia’s Vidalia and Hawaii’s Maui onions, look a lot like white onions. They are also great for eating raw. But unlike white onions, they need to be wrapped in a paper towel and stored in the refrigerator due to their high water content.
- Green onions, also known as scallions, can be used as an onion and herb all at once. The white end acts much like a white or sweet onion to add a mild sweet flavor, and if left raw, a nice juicy crunch. The green tops have a bit more flavor, and are typically used more like an herb.
- Spring onions look almost identical to green onions, but they have a slight bulb on the end. Green onions will never grow a bulb, where spring onions are just white or yellow onions that are harvested early. They are only available seasonally. Although they would work interchangeably with green onions; if you want to taste them at their best grill, roast or braise them whole.
- Leeks, which look like giant green onions, should be treated quite differently. They are much more fibrous, so they are usually not eaten raw. They are much more commonly found in soups and stews. Leeks should be washed well before eating.
- Green onions, spring onions and leeks must be refrigerated and should be stored in a reusable mesh (don’t use plastic) bags. However, if they still have their roots, try trimming them slightly, and then store them in a container with a small amount of water.
- Shallots are a great alternative to a yellow onion, with a hint of garlic flavor. The flesh of a shallots is much thinner than an onion, making them ideal for sauces and dressings.
- Pearl onions are just tiny sweet versions of white, yellow and red onions. Blanching them can help get the skin off, if you are trying to use fresh. They work well roasted, braised, pickled, creamed or glazed. Shallots and pearl onions are best stored at room temperature, like you would large bulb onions.
You can’t go wrong, no matter what onion you choose, if you use them in the proper way. They add flavor and plenty of nutrition, too.
Lauren Cornay, RD, LN, is a registered dietitian with Avera Heart Hospital. Get more information on nutrition and diet.