Preserving Onions: How to Make Onion Powder in 6 Easy Steps!

It’s no secret that we love to dehydrate things around here. It is such a great way to preserve so many types of foods! Onions are no different. Whenever we have a large harvest of onions, we always turn some into powder for long-term storage. Truth be told, onion powder just might be my favorite of all our homemade seasonings. Shhh! Don’t tell the garlic powder.

Homemade onion powder is sweet, herbaceous, and versatile – adding the perfect pop of flavor to dang near any meal! The smell reminds me of onion bagels… Yum! Onion powder is also super simple to make, and requires significantly less work than creating garlic powder. When dried properly, it will last over a year in your pantry. Come follow these 6 easy steps to make your own too!

What kind of onions should I use to make homemade onion powder?

You can use any kind of onions to make onion powder: red, yellow, white, sweet, spicy, small, large… We tend to grow mostly sweeter white or red onions, which helps make our resulting onion powder nice and sweet as well. Since you can dry and use all parts of the onion, making homemade onion powder is as an excellent way to reduce waste.

For instance, sometimes our onions begin to flower before they fully bulb up, meaning they will not be able to cure for long term dry storage. That also means we’ll have A LOT of fresh onions on our hands at one time – more than we can use before they’d go bad. On the other hand, our cured onions sometimes start to sprout after months of storage. Sprouting onions are still good to eat, but need to be used ASAP. Homemade onion powder is the perfect solution! Even more, the green leaves from all onions can also be dried and turned into powder with the rest of the onion.

HOW TO MAKE ONION POWDER

Supplies Needed

• Onions – Make a little, or make a lot! To create a full pint of powder, we used most of the onion bulbs shown above, plus about half the greens.
• A food dehydrator or oven. The use of a dehydrator may be preferred for optimal quality and health benefits, explained further below.
• A good blender, food processor, or coffee grinder. We use a Vitamix.
• Airtight storage containers, such as mason jars.

Oven-Drying Versus Using a Dehydrator

You can make onion powder in a food dehydrator (our preferred method) or dry onions in the oven. I’ve included instruction for both below. We prefer using a food dehydrator for a number of reasons. First, using a dehydrator allows us to “set it and forget it”. No stirring and fussing over the hot oven needed. There is also zero risk of burning it, and ensures even and consistent drying.

Another important aspect (in my opinion) is that a dehydrator allows us to dry the onions while also preserving the nutritional value.  While we do not follow a raw food diet, we try to avoid exposing our food to excessively hot temperatures when we can. Especially healing foods like onions! If you read our Fire Cider recipe, you’ll remember that onions have stellar immune-boosting, inflammation-reducing properties. When food is exposed to heat over 118°F, it will reduce beneficial nutritional properties, antioxidants, and active enzymes. Therefore, we dry our onions around 100-110°F.

Low, and slow.

INSTRUCTIONS

1)  Clean and Peel Onions

If you are using fresh homegrown onions, the roots and greens may still be attached. Wash them to remove excess dirt, and cut away the tough bottom bit that is attached to the roots. We also find it easier to cut the green tops off, and set aside in their own pile to process separately from the bulbs. Peel away and remove the outermost papery skins of the onions.

2) Thinly Slice Onions

Cut the onions into thin, even slices. The thinner the slices, the more quickly they will dry. Furthermore, the more consistent the cuts, the more evenly they’ll finish drying together. We typically aim for about 1/8” to 1/4″ thick, if I had to measure – which I don’t! For green onion stems, you can either cut them into rounds or long slender pieces.

Lay the slices of onion out evenly in a single layer on your food dehydrator trays as you go. You can pack a large amount on to each tray! The pieces can touch side to side, but make sure they aren’t piled on top of each other. We need some space for good air flow between them.  

Tip: Did you know that holding a piece of citrus in your mouth while chopping onions helps reduce the sting and tears? It really works!

3) Dehydrate the Onions

Load up your food dehydrator with its trays full of onions, and turn that puppy on! We choose to dry ours on about 100-110°F. Again, this is because we don’t want to overheat and essentially “cook” the onions, denaturing its beneficial enzymes and antioxidants. If you aren’t overly concerned about that, you can use a warmer setting (around 135°F) to get it done much faster. It will taste just as good!

The time it takes to fully dry will vary. It depends on your dehydrator or oven, how you prepared and organized the onion, and the temperature you use. When we used our old Nesco dehydrator, it took several days on 110°F to completely dry. Our Excalibur dries it nicely in about half that time, and could easily do it in less than 12 hours on a higher setting than we use. (Keep reading below to see how to tell when they’re “done”.)

Tip: Onions smell very pungent as they dry. If possible, you’ll want to put the dehydrator in a separate room with an open window. We sometimes put ours in the garage.

Drying Onions in the Oven:

To dehydrate onions in the oven, prepare them in the same fashion as described above. Next, spread them in a thin layer on a baking pan covered with parchment paper. Bake at 140°F until they are completely crunchy dry. It is suggested to stir and re-spread the onion bits every 30 minutes as you go. We have never done this, but read that this method takes several hours.

4) Check Doneness

Before removing the onions from your dehydrator or oven, check to make sure they are totally crispy dry! If you try to break them, the thin dry slices should snap and crack crisply in half, and not bend or be malleable at all. The texture tells you if all the excess moisture has been removed. If they’re still bendy or soft instead of crunchy, keep on drying!

If too much moisture is left, your powder will clump up later in the storage container. 

You may find that some are done and some are not. Also, onion greens tend to dry much faster than the bulb portion. In that case, you could either pull out the crispy ones and continue to dry the others, or just keep drying it all. We’ll often keep all the green onion leaves on separate trays than the other onion slices. That way, we can pull out those trays of greens when they finish more quickly than the rest.

Once it is dry as tinder, it’s….

5) Time to Grind!

Next, it is time to grind your crispy dry onion bits into homemade onion powder! This can be done in a blender, food processor, or coffee grinder. In a Vitamix, the result is a super fine, fluffy onion powder. Pulse and grind it until all the chunks appear to be broken up.

6) Store

Finally, transfer your finished homemade onion powder into an airtight storage container. We typically use mason jars, either half-pint or pint-sized, depending on how much we make. Repurposing old spice containers would work well too! You’ll probably want the assistance of a funnel here, so you don’t spill your precious goods. Our canning funnel is our best friend when we’re working with mason jars.

When stored in an airtight container, homemade onion powder is good for up to a year! And hot dang, is it good… We have enjoyed year-old onion powder that had no obvious degradation in quality or taste, though we usually go through it much faster than that. Good thing onions grow quicker than garlic – so we can make several batches per year to easily replenish our supply!

7) Enjoy Your Onion Powder

I’m sure you can all figure out a million wonderful ways to use your homemade onion powder, right? Well, just in case you need some ideas: Add it to fresh salsa, guacamole, sautéed or roasted veggies, in tomato and pasta sauce, soups, curry lentils, chili, hummus, salad dressing, egg dishes, sprinkled in with cooking rice or pasta, or added to homemade sourdough or herb sourdough pizza crust (yeah, that is as delicious as it sounds)… There are limitless options! 

Voilà!

You have successfully made your own onion powder! Wasn’t that easy? In all, I hope you have enjoyed this article, and feel empowered and excited to go make your own. I will work on making a “how to grow onions” article soon. Please feel free to ask questions, and spread the love by sharing this with all your onion-loving friends!

If you liked this tutorial, you may also enjoy: How to Make Garlic Powder or How to Make Homemade Chili Powder. The process is very similar, but with a few minor tweaks!