Why do onions make you cry? Are onions keto? Find out in this month’s produce guide: The Ultimate Guide to Onions! From hair growth to curing a common cold, there are many questions about onions. Ever wondered where these staple veggies came from? Or how do onions grow? And then there is the ongoing question of the best way to caramelize onions, or can onions be frozen? Look no further than this Ultimate Guide to Onions to learn everything about growing, cooking and nourishing about these lovely alliums.
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Onion Origin and Growing Information
Where do onions come from?
Onions were one of the earliest domesticated crops. They were originally cultivated in Iran and Pakistan. Due to their ease of growing, transportation and storage, they were likely a staple of the prehistoric diet. In ancient Egypt, onions were worshiped as a symbol of eternity and were buried as a sacrifice to a new Pharaoh. In several cultures, onions were used as medicine as well.
Where do onions grow best?
Onions are grown coast to coast in the US due to their hardiness and simplicity. Onions are commercially grown in over 20 states, including Vermont! Don’t worry about the soil, as onions can thrive in virtually any conditions so long as they are watered well.
How do onions grow?
These delicious alliums are a cold-weather crop, so they are typically planted in early spring and harvested in the late fall or early winter. Onion sets can be used to make them resistant to frost damage. They seed about 4” deep and should only be buried one inch below the soil, so they are perfect for a raised bed or small hoop house. If mulch is used, onions only need to be watered about once a week. However, onions will appear healthy even when they are bone dry so be sure to water well and soak the roots. Fun fact/wives tale: the thicker the skin on the onion, the harsher the upcoming winter will be!
When do you harvest onions?
Once the onion plants start sending up flowering stalks, it means they have stopped growing. These onions are not mature, but can be used within a few days. Once these flowers have turned yellow and start to fall over, the onion has matured. Mature onions can be pulled out of the ground at the base of the exposed flower, and stored in cool and dry conditions.
Cooking and Preparing Onions
Where should you store onions?
Store onions in a cool, dry place, ranging from about 40-50 degrees. Cellars or cool basements are perfect. Once you harvest the onions, let the onions cure on dry ground for a few days if weather permits. Do not store onions next to any high-ethylene fruits, such as apples or pears, as they encourage rotting and over-ripening. Onions should be kept in mesh bags or nylons to help with dryness. Kept on a typical counter, onions should keep four to six weeks.
Can onions go bad? How do you tell?
Unfortunately, onions can go bad. As with most fresh produce, check with your senses to tell if an onion has gone bad. If an onion is mushy, has black spots or obvious mold, it has probably gone bad. Onions can sprout if kept in the dark, much like potatoes, and they are still perfectly safe to eat. However, if the sprouts are soft or off-color, it is another sign your onion is no good.
Can you freeze onions?
Onions can be frozen, though it may slightly affect the texture and mute the flavor. This can be a great strategy to save onions you are worried about going bad. Chop up an onion to the size you look to use it and store it in an airtight bag. Freeze for two to three months. Note they will be wet when you thaw them. Drain away excess moisture and cook them as directed adding more time to evaporate any excess moisture if necessary.
How do you caramelize an onion?
We all know the delectable, sweet, tangy flavor of caramelized onions… but how do you create this at home? Several types of onions can be caramelized, including white, yellow and red. Onions caramelize when the large sugar molecules that naturally occur in the onion is broken down into simpler sugar molecules. This increases the sweetness and deepens the flavor of the onions. To caramelize an onion, french slice them, and add to a cold saucepan or skillet with oil or butter per onion. Cover and set over medium high heat. Cook and stir the onions as they release their liquid and soften. If they become dry add in a few tablespoons of water or reduce the heat. Once the onions are soft, remove the lid and allow any liquid to evaporate. They will start to brown. (Due to the lack of moisture- the sugars will be able to caramelize.) Keep an eye on them, and stir often until the mixture is golden brown and caramelized. Caramelized onions can be eaten immediately, or stored (if you have more self control) for up to a week in the refrigerator. Try them on pizza, in lasagna or on baguette for an appetizer.
How do you pickle onions?
Pickling onions is a similar process to pickling beets or carrots or any other vegetable. I love pickling them in Maple Syrup! Here is my favorite way to do that. Alternatively, try table sugar: Combine ½ cup vinegar, 1 cup water, 1 tablespoon of sugar and 1-2 teaspoon(s) of salt. Whisk to combine. Add to a mason jar with one philly cut or sliced onion (use a mandoline to cut as thinly as possible). Refrigerate for at least one day before enjoying. Red onions provide the nicest vibrant pink results, but yellow, sweet and white onions can also be pickled!
Which onions are the sweetest? Mildest?
Each type of onion has its own unique characteristics. Lets break down what they are:
Yellow onions: These are the “all-purpose” onions. They are used most often and get sweeter as they cook. These are perfect for stews, sautés or caramelizing. An example of a yellow onion is a Spanish onion.
White onions: These tend to have a slightly sharper flavor and are more commonly used raw for salsas or chutneys. However, they can be sautéed for a variety of dishes.
Sweet onions: These, as the name would suggest, are the sweetest and mildest of the onions. They lack the sharpness and acidity of other onions. Types of sweet onions include Vidalia and Walla Walla.
Red onions: These are the most eye-catching of the onions, with their red flesh and softer texture. These are similar to yellow onions in taste, but are also totally suitable to be eaten raw in salads or salsas. Unfortunately, when red onions are cooked they lose their beautiful color. If their strength is unappealing to you for eating raw, soak them in water for a few minutes before serving.
Nutrition of Onions
Which onions are the healthiest?
All onions have the same macronutrient and micronutrient profiles. The only thing that slightly differs is the amount of phytonutrients, which are antioxidants that show themselves through pigment. So, naturally, red onions would have slightly more phytonutrients than yellow onions, and white onions have the least phytonutrients. However, these slight differences do not drastically improve health.
Can onions cure a cold?
While a brothy soup that contains onions may feel comforting when you’re sick, it alone probably won’t cure you of your cold. The home remedy of onions curing illness started in the 1918 flu pandemic. Doctors would prescribe that families keep a cut onion at the bedside of a sick person so it would absorb the germs in their body. As a result of modern medicine, we now know that that is not how illness works. Additionally, vegetables may rot as a result of their own bacteria but they cannot absorb bacteria from the air and hold on to them. On the other hand, a diet high in vegetables and fruit is one of the best ways to prevent illness, and onions can absolutely be included in that.
Do onions help your hair grow?
The sulfur in onions is thought to stimulate hair growth when applied topically. However, the only study to find significant results for the use of onions was from applying onion juice to the scalp twice daily. About 70% of people with hair loss saw regrowth after 6 weeks from this method. For those of us who would rather avoid smelling like onion juice, eating onions (cooked or raw) provides sulfur that, though it is less concentrated, can still marginally help hair growth.
Are onions keto?
As with anything, the carbohydrate content depends on how much you eat. For example, ¼ cup of cooked onions contains about 5 grams of carbs and ¼ cup of raw onions contains about 4 grams of carbs, making it keto acceptable. There is slight variation between onions, but it is marginal. Most all non-starchy vegetables are nutrient-dense and important to include as a regular part of your eating pattern, keto or not.
Why do onions make you cry?
To stay out of the weeds on this one, the short answer is that onions release a slightly unstable chemical once they are cut. This is a type of sulfenic acid, a derivative of sulfur, which irritates the glands in our eyes that cause us to cry. There are several ways that people cut up onions without irritating their eyes, but they are all individual depending on your sensitivity to the acid. If onions make your eyes water, things to try include soaking the onion in water, keeping a piece of bread in your mouth or keeping the sliced side facing down. My mom gave me a pair of these onion goggles, and they actually work, but I ended up getting rid of them because they took up too much space in my kitchen drawer. If you are particularly sensitive, they may be a good option/worth the drawer space for you.
Added bonus: check out this post on how to properly dice an onion!