Dehydrated Onions | How to Dehydrate and Store Them

I just did another batch of dehydrated onions! During the time of the year when harvest is plenty, it’s time to preserve the bounty. Or, if something goes on sale, like Vidalia onions (my favorite)!

I have preserved batches of Vidalia onions with my dehydrator for long term food storage. Here’s why, and how.

(UPDATED, again!)

Why dehydrated onions?

When Vidalia onions are plentiful at our local produce market, and the price is right, we buy lots of them to dehydrate for later. I like the taste of these onions.

When winter comes along, we will have plenty of onions! In this case, my favorite, Vidalia onions from Georgia. It’s better than having to buy onions that have been shipped up from Mexico or South America during our winter!

How To Dehydrate Onions

Tip: When dehydrating anything, you must use quality fresh produce to ensure good and lasting results.

The process is really quite simple. Of course you need a food dehydrator (I use the Excalibur).

Cut the two ends off the onion.

Peel off the onion skin as you normally would. I tend to peel off the thick outer layer too, depending on how it looks.

sliced onions for dehydrating

Slice the onions thin (1/8 – 1/4 inch)

Cut the onion in half, and slice it into no larger than 1/4-inch thick slices. Even thinner if you can. However be as consistent as possible with the thickness. If some are too thick, they won’t dry the same as the others.

UPDATE: Our most recent batch while dehydrating onions… I used this hand-crank slicer that we had picked up at a yard sale. Wow, it worked great!! I set the thickness for about 1/8 inch. Here’s some pictures of it:

Using a meat slicer for the onions

Cut – Chop the sliced pieces

Some people like to chop up their onions fairly small. Whereas I like longer pieces as shown in the images here. It really doesn’t matter. Once the dehydrating is done, you can crunch them up smaller if you want to…

First I slice them as shown. Then, I just mix them up in order to dump them on the dehydrating trays.

chopped onions for the dehydrator

Fill your dehydrator trays!

onions on dehydrator tray
Excalibur dehydrator for onions

Important: Put your dehydrator outside!

The smell of onions will be strong!
Ask me how I know…

This is THE most popular dehydrator cookbook:
The Ultimate Dehydrator Cookbook
(view on amzn)

Set the temperature for 145-degrees F.

The total time will depend on the moisture content of the onions, how think you’ve sliced them, and the tempoerature of the dehydrator.

My typical batch takes (about) 9 or 10 hours. You results may vary.

Dehydrate until nearly brittle. Or at least very leathery. Keep in mind that the dryer they are, the longer the shelf life.

How do you know when the onions are done? The small pieces will tend to snap in half while the larger pieces may be very leathery but obviously dry.


How much do dehydrating onions shrink?

Well, it just so happened that one large onion fit on one tray of the Excalibur dehydrator. The end result was about one-third to one-half a cup of dehydrated onions per large onion.

After squishing them into quart-size widemouthed canning jars, I got about 8 onions equivalent per jar.

One large onion dehydrated to 1/4 cup

How To Store Dehydrated Onions

When they’re done, I keep the onions in ordinary canning jars for convenience.

quart size canning jar holds 8 dehydrated onions

The ‘working’ jar, or the one in current use. I use a wide mouth plastic lid for convenience. I vacuum seal the other jars for longer shelf life.

Plastic Lids for Canning Jars
(view on amzn)

I use a FoodSaver jar sealer accessory (connects to my vacuum sealer hose attachment). This will greatly prolong the shelf life. It simply removes the air from the canning jar (while using the existing canning lid and cover). I will reseal after each time I take out some of the contents.

I use the wide-mouth quart jars because they’re easier to fetch the contents.

How Long Dehydrated Onions Last

Let me put it this way… Awhile ago we ‘found’ (in our food storage) a vacuum sealed jar of dehydrated onions dated 6 years prior. (We always write the month/year on the lid). It was perfectly fine!

If they have been dried and stored properly, shelf life of dehydrated onions will last many years.

With that said, it’s a good rule-of-thumb to try and consume your home dehydrated foods within a year for optimal results. You can always make more if you’re running out, right?

My 9-tray Excalibur Dehydrator makes about 6 pounds of sliced onions per batch, which fills nearly 1 and a half quarts of mason jars.

[ Read: Things You Can Seal With A Vacuum Sealer ]