I try not to buy too many countertop appliances, but after three years, Kirk wore me down on the whole concept of air fryers. My only request was that it have enough space to cook for everyone in our family, and that the interior be made of metal.
He picked up a Ninja Double Stack Airfryer in the 8-quart size. This is a large machine, but it doesn’t occupy a lot of counter space. It can cook both sections at the same temperature or at different temperatures and times. You can have it air-fried in one and roasted in the other. It has six functions: Air Fry, Air Broil, Roast, Bake, Reheat, and Dehydrate.
I wondered how the dehydrator function would work, so I got four Gala apples, which I had recently dehydrated a batch in our dedicated dehydrator. I wanted to compare how the Ninja worked to a traditional dehydrator.
Wash and dry the apples, then peel them. I cut them into four sections, cored and thinly sliced. While I worked, I had a mixing bowl filled halfway wth water and a glug of lemon juice, to prevent browning. Slip the sliced apples into the water. Once done, I drained and spread the apples onto paper towels to dry off, then I divided them between the two cooking sections. I could fit about two apples’ worth in each section.
The Ninja has “crisping plates” that go into the bottom, and I made sure they were at the bottom as directed. And then spread the apples on it. This allows air movement under the apples. In theory, I could have added a second layer on top, as the Ninja comes with metal racks that have legs, allowing one to cook two separate items simultaneously. I didn’t worry about this, this time.
The directions will, of course, vary with your air fryer, if you have this option.

Top section loaded. We have very hard water, so disregard all the carbonate stains.

Bottom section.
I set both sections to 135° and set the timer for 7 hours. Every 2 hours, I opened the trays and shook them gently, and left them to do their business. The manual says 7 to 8 hours for apples. As I sliced them thinly, 7 was plenty.
I let them cool down and then stored them in a mason jar.

I decided to compare the apple slices to the ones we had recently dehydrated.

Dehydrator on the left, air fryer on the right.
The ones from the air fryer were far nicer – and better tasting. The texture was thinner, dry yet chewy. They had been cut to the same width. However, the air fryer did a faster job of drying, taking less than 7 hours, compared to over 24 hours for the dehydrator. Now then, you cannot dry as much in one run with the air dryer. But f it is just for one or two people? Then it can be better. Just one appliance – dehydrators are not a small countertop appliance. If you are doing a lot, then no, the air fryer isn’t a good choice. However, if you need snacks or a single ingredient, then go for it.
~Sarah