How Does a Dehydrator Work? See How It Dries Your Favorite Snacks

oranges in a food dehydrator

Sometimes, you’re just in the mood for a snack. If you have a food dehydrator, you can have all sorts of tasty dried snacks around all the time. That leads us to the question: How does a dehydrator work?

How Does a Dehydrator Work?

If you’re wondering what a food dehydrator is, one of these contraptions is exactly what it sounds like. It’s a kitchen appliance that you use to dry out food.

But you probably already knew that. What you’re wondering now is, how does a dehydrator work?

Before modern times, our distant ancestors would actually dehydrate food themselves. They would simply place the food out in the sun to dry out.

Although they eventually created more complex apparatuses that involved solar dehydration, these dehydrators weren’t nearly as efficient as the ones that are available to you today, such as the Excalibur 3926TB or the Nesco FD-1040 Gardenmaster.

Devices of the olden days had to rely on the natural movements of air and the sun, while dehydrators today have components that ensure even circulation of warm air to dry out food.

So how does a dehydrator work? You’re about to find out now!


Although there are several unique models of dehydrators, they all have a few common features. Generally, they operate using some sort of heating element, air vents, fan, and trays that hold your food.

The dehydrating process

Of course, you’re still wondering, how does a dehydrator work? All the components of the dehydrator work together to remove the moisture from your food.

The heating element heats the food up, which allows it to release its moisture into the chamber of the dehydrator. The heat causes the water to evaporate from the food. Then, the fan will push all this excess moisture to the vents, which will release the moisture outside of the device.

Most foods go through the dehydration process at temperatures that lie somewhere between 95 and 145 degrees Fahrenheit. You should dehydrate meats at higher temperatures then fruits and vegetables because the lower temperature ranges might make your meats more susceptible to bacterial growth.

Even though it may be tempting because you think you’ll get quicker results, be careful not to dehydrate your foods at too high of a temperature. It’ll likely lead to food that’s dry on the outside and still moist on the inside.

In some dehydrators, air will circulate vertically; in others, it circulates horizontally. If it circulates vertically, the fan will be on the bottom or the top. If it moves horizontally, the contraption will have a rear mounted fan.

There are often multiple tiers of trays so that you can dehydrate different types of food at the same time. The separation via the presence of multiple trays ensures that none of the flavors of different foods that you’re putting in there are going to be mixed, which is extremely convenient.

You might not have been expecting this as the answer to the question, how does a dehydrator work? The truth is, though, that dehydrators are fairly simple and straightforward in their functioning. And they are very useful as well.

Reasons to Use a Food Dehydrator

There are many reasons why you would use a food dehydrator. These go beyond seeing a live demonstration that can answer the question, how does a dehydrator work?


The most obvious reason you’d want to dehydrate your food is that it’ll last longer that way. Without all the moisture that they have in their natural states, they’ll be impervious to spoilage and infection via different types of bacteria.

It’s pretty amazing how long some of these foods will last if you store them properly.

Powdered milk or milk substitutes will very likely last for up to 20 years. If you dehydrate fruits, vegetables, pasta, corn, wheat, rice, or other greens, you can expect them to last up to 30 years. Of course, you have to make sure that you pack the food in airtight, moisture-proof containers.


If you’ve ever tried to get dried snacks in a store, you’ve probably seen that they can be pretty expensive. If you use a food dehydrator instead, you can get those same snacks at a fraction of the expense.

Considering that dehydrating these foods can make them last for decades, don’t you think it’s worth it to have the option at all times?


Many people think that cooking or dehydrating food will take out all the nutritional value. However, this is not the case at all.

If you dehydrate vegetables, the end result will still be high in fiber. Dehydration will take almost no vitamin C away from the food, and it’ll also allow the preservation of all vitamin A or beta carotene.

You can also expect the retention of minerals, such as magnesium, potassium, and selenium.

How to Work with Your Food Dehydrator

Of course, you can’t just shove food into your dehydrator and expect it to work magic. You need to be able to work well with the contraption.

It’s fairly simple, but there are a few things that you should keep in mind when you’re working with a food dehydrator.

1. Don’t skimp on the prep work

Considering that a big part of why you are dehydrating this food is that you want to avoid spoilage, you should make sure to get rid of all bacteria before the dehydration process.

Before you put them into the device, make sure that you thoroughly wash all of the foods you’re planning to dehydrate with an antibacterial food cleaner.

Also, make sure you’re wearing gloves while you’re handling them, so you don’t get skin oils on the food.

If you have low acid vegetables, steam them for about 10 minutes, and then pat them dry before you put them in the dehydrator. Apples and bananas should be spritzed with lemon juice, in order to avoid excessive browning.

You should also preheat your dehydrator, the same way that you would pre-heat your oven before you bake something. You just need to turn it on and let it warm up to the required temperature before you put the food in.

If you want the best possible results, you should put items that require the same temperature for dehydration in at the same time. Also, try to slice all of your items so that the pieces are of equal sizes and thicknesses. This way, you can be sure that everything is dehydrated equally.

2. Don’t just crank it up all the way

Some people might be tempted to turn up the temperature settings all the way because they think the food will dry quicker. However, this isn’t really how it works. All it’s going to do is seal the outside and leave moisture on the interior, which means the food is going to spoil before you have a chance to eat it.

The appropriate temperature depends on the type of food you’re trying to dehydrate, as well as the exact model of dehydrator you have.

Each dehydrator is going to come with general guidelines when it comes to time and temperature for different foods. This can help you figure out how to estimate the times and temperatures for your batches of food.

3. The 95 percent rule

You should try to make sure your food is at least 95 percent dehydrated. If the food feels sticky, spongy, or soft, you should just put them back in the dehydrator and let them dry out some more. Items are done when they are crunchy, hard, or even breakable.

You might need to dehydrate the foods for longer than guidelines would suggest if you have high indoor humidity, stronger than average breezes, or potent air conditioning. Try to keep your dehydrator away from windows and air vents. Instead, set it up in a place that is warm and dry while it’s doing its work.

Dying to Start Drying out Some Food Now?

Now, you’ve learned quite a bit of interesting information about food dehydrators. This information goes beyond a simple answer to the question, how does a dehydrator work? You also know why it’s so useful and what you can get out of it.

If you’re interested in dehydrating food so you can have delicious snacks around the kitchen that you can keep around for a long time, you should definitely look into getting this appliance for yourself.

It doesn’t require a lot of work from you, because it does the work on its own. Also, if you enjoy dried snacks, this is one purchase that is worth every penny.

As you have seen, there is a fairly simple answer to the question, how does a dehydrator work? You likely didn’t have much trouble understanding the principles on which its operation is based. You might be more excited, however, at the prospect of actually using a dehydrator to make delicious snacks!

What do you think of everything you’ve just learned about how a dehydrator works? Share your opinion in the comments section!

Last update on 2021-09-18 at 06:50 / Affiliate links / Images from Amazon Product Advertising API


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