Produce Spotlight: The Ultimate Guide To Onions
From hair growth to curing a common cold, there are many questions about these staple veggies. Ever wondered where onions came from? Or how do onions grow? And then there is the ongoing question of how do you caramelize one, 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.
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.
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, cut into thin slices. I like to use a French Cut for caramelized onions because they do not break down even with the long cooking time.
How To French Cut Onion
How To Cook Caramelized Onions
- Swirl oil in the bottom of an unheated heavy-bottom saucepan. Add onion and some salt. Doing this will prevent the onions from frying and browning in the oil, and will allow them to sweat out their moisture. This allows them to soften before browning, which is KEY to caramelized onions soft texture.
- Cover and set pan over medium-high heat. Then from there, let the onions cook, removing the lid and stirring occasionally, until the onion starts to brown along the edges, 8 to 9 minutes.
- Once the moisture starts to reduce, you’ll have to drop the heat to medium low.
- Then just continue cooking, adding 1 tablespoon of water at a time as necessary to prevent burning, until the onion is browned and soft, 7 to 10 minutes longer.
Steps To Caramelize Onions
Added bonus: check out this post on how to properly dice an onion!
How do you pickle onions?
Pickling onions is a similar process to pickling cucumbers or any other vegetable. 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 slivered onion. Refrigerate for at least one day before enjoying. Red onions are most popular for pickling, as they result in a vibrant pink color.
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 little bit sharper of a 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.
Onion Recipes
vegetarian caramelized onion and mushroom lasagna
roasted delicata squash salad with warm pickled onion dressing
beet and caramelized onion bruschetta with goat cheese crumbles
minestrone soup cooking the onions until they have a bit of fond at the beginning of this soup is key to rich flavor.
PrintCaramelized Onions
- Total Time: 25 minutes
- Yield: 1 1/4 cup 1x
Description
How to make caramelized onions without burning them. Use a covered saucepan and control the amount of browning by adding water as they soften.
Ingredients
1 tablespoon plus 1 teaspoon avocado oil or olive oil
2 large onions, into thin slices
1/4 teaspoon salt
2 to 4 tablespoons water, as necessary
Instructions
- Swirl oil in the bottom of an unheated heavy bottom saucepan. Add onion and salt and place cover on top. Set over medium-high heat.
- Cook onions, removing lid to stir every minute or two until the onion is soft and starting to brown along the edges, about 5 minutes.
- Remove lid and reduce heat to medium-low. Continue cooking, uncovered stirring occasionally 7 to 10 minutes. You may need to add 1 tablespoon of water at a time to prevent burning before the onions are completely softened. Onions will be done when they are completely soft and browned.
Notes
Tip: When the onions are done, if browned bits have formed along the bottom of the pan, leave the saucepan off the heat, covered for 3 minutes. Remove lid and stir and the caramelized bits will melt into the onions.
- Prep Time: 25 minutes
- Cook Time: 20 minutes
- Category: Side Dish
- Method: Stove Top
- Cuisine: American
Nutrition
- Serving Size: 1/4 cup
- Calories: 48 calories
Thank you for so much information about onions!!
Hey Meredith! I hope you leaned a lot! Thanks!
Such a fun topic! My husband always gauges where our food supply is based on onions and garlic LOL! We love them!
Renee,
I could not agree more- that’s a pretty good way to base the food supply! We love them as well!
I love onions and enjoyed reading all of the onion facts in this post!
Hey Anne- so glad you enjoyed the post and wee able to learn from it!
What a great write up. Will come back here often.
Zuzana,
Thanks so much for the comment! Please come back any time!
Such a fun post! I learned so much! Thanks!
Thanks Megan! I’m so glad that you were able to learn something new!
I love onion and I eat it in some way almost every day. Pickled red onions goes with so many dishes, and I know its very healthy 🙂
Thanks for a good post
Handla,
Thank you for your post, and I agree! Pickled red onions are so good in so many ways!
Such an awesome resource! Never thought to freeze onions and will have to give it a try.
Matthew,
Thanks for your comment! Glad you were able to take something from it!
Neat! I never knew that release something and that’s why you cry- cool!.. and creepy lol
Shelby,
I can’t disagree with you! Onions are a crazy, cool, and sometimes creepy thing 😉
Shelby- It’s all true! Onions are crazy, creepy, but oh so cool 🙂
I did hear about onion juice for hair growth but am not prepared to do that myself. I’ll still to yummy caramelized onions!
Kelly- you use those onions in whatever way best suits you 🙂 Who knows- maybe it’ll come up in trivia someday and you’ll know! 🙂 Thanks for the comment!
Love onions. I use them in almost everything I cook, it seems like! This guide is really helpful!
Same here! They are such an easy way to add loads of flavor and depth to dishes in a healthy way.
So many fun facts! I love this as much as I love onions.
Aw, that’s a great way of putting it! Thanks Jori.
What a great tutorial. I really appreciate this.
Thanks So much Andrea. I am psyched you enjoyed this post so much. Have a great day!
Such good information on onions. I learned so many new things about onions. I especially like the part about why they make you cry.
Isn’t that part interesting! It’s funny you don’t really smell a “sulphur” smell when cutting them. More like onions, lol. But that’s the culprit!
This is crazy! I was literally just thinking today that someone should really write about just how useful and versatile onions are…and then I read this! This is a fantastic guide to one of the most used but underappreciated veggies out there.
You are not alone. My assistant/food stylist Stephanie just mentioned it to me yesterday too. So funny! Great minds. Have a wonderful weekend Cliona.
What a fun post! I loved learning more about onions. 🙂
Hi Raia, Thanks so much. I am psyched you enjoyed reading it. We had a lot of fun putting it together.