Freeze Dryer vs. Dehydrator: The Pros, Cons, and Logic

Let’s start with the basics: Both dehydrators and freeze dryers are used to remove moisture from food—but they operate on different principles and have distinct purposes. 

A Dehydrator uses a heating element and a fan to circulate warm air around the food to remove the moisture.  Sufficiently high heat can seriously hamper or even kill bacteria and weaken other elements that can cause food to “go bad”.  This helps a dehydrator prepare food so that it lasts for weeks or sometimes months, much longer than fresh food would ever manage.

A freeze dryer, on the other hand, stops the deterioration process much more thoroughly by removing more moisture and much of the available oxygen needed by bacteria, mold, and enzymes.  Without these two vital elements, deterioration stops for decades instead of just months, putting the food in a form of suspended animation.  The process involves freezing the food and then lowering the pressure, which allows the frozen water in the food to sublimate directly from ice to vapor without passing through a liquid phase.

Dehydrators operate at much higher temperatures, usually between 100°F (38°C) and 165°F (74°C), so people ask does this “cook” the food?  The answer is that the dehydrator does not cook it in the traditional sense.  Its primary purpose is to preserve food by reducing its moisture content, which inhibits the growth of bacteria, yeast, and molds. 

It can alter the texture and taste of food by removing water.  This is particularly useful for preserving fruits, vegetables, herbs, and even making items like beef jerky but it will result in a product that may be chewy or leathery, and the color may darken.  Some nutrients may be lost due to the higher temperatures.

Freeze Dryers, on the other hand, operate at much lower temperatures during the freezing stage and even lower temperatures during the drying stage. This helps preserve the color, texture, and nutritional quality of the food better than traditional dehydrating.

Your food is still going to look much the same as it did when you began, and it can be restored by resupplying the original amount of water that was removed initially.  This is why people weigh the frozen food before freeze-drying and note the weight when the process is complete.  They then know precisely how much water to add when they want to rehydrate the food.

While dehydrators are good for preparing dried fruits, jerky, some types of dried vegetables, and of course herbs, they are not as versatile as freeze dryers.  The latter can manage everything the dehydrator can produce, but are better for a wider range of foods such as fruits, vegetables, meats, dairy products, and even complete meals.

Which one is right for you?

The decision between buying a dehydrator or a freeze dryer depends on your specific needs, preferences, and budget. Here are some considerations to help you decide:

Buy a dehydrator

1. if budget is a consideration, since they are a lot more affordable ($50-$200) than freeze-dryers ($2000-$4000).
2. for the choice for pure simplicity, requiring little more than the knowledge to plug them in.
3. if you primarily want to make items like dried fruits, jerky, or certain types of dried vegetables, a dehydrator may be sufficient.

Buy a freeze dryer

1. if you prioritize preserving the original color, flavor, and nutritional content of a wide range of foods, the freeze dryer is a superior tool compared to a dehydrator.
2. if you have a wide selection of foods to preserve—because freeze dryers can handle a broader selection, including fruits, vegetables, meats, dairy products, and complete meals. If you want to preserve a diverse range of foods, a freeze dryer is more versatile.
3. if you're looking for a longer shelf life for your preserved foods, a freeze dryer is a better choice. Freeze-dried foods generally have a significantly longer shelf life compared to dehydrated foods.

Can you make freeze dried candy in a dehydrator?

 The answer is No. Freeze-dried candy is popular for its crispy texture and intensified flavor, attributes that are specific to the freeze-drying process. This distinct texture of freeze-dried candies emerges only under strong vacuum conditions. Given that dehydrators lack a vacuum mechanism, they are unsuitable for producing 'freeze-dried' candies.

Do You Need Both?

What if money is no object…would having both be a good idea?  Dehydrating is fast and simple if you need “trail food”.  Meals require a little more work to preserve successfully, but the payoff is instant food upon need that is nearly indistinguishable from something you just cooked on the stove!

Freeze Dryers take more space and have more equipment, but modern ones are well-made and durable—some early models are even in their second decade of life!  They’re also more expensive, but over their lifetimes will pay for themselves over and over.

Freeze dryers are an investment.  If you’re growing things and can’t tolerate wasting production that you can’t use immediately, then preservation is for you.  Freeze dryers will let you preserve things longer, and in greater variety.

The Takeaway

Dehydrators are simpler, faster, and less expensive, but freeze dryers offer superior preservation of color, flavor, and nutrients, and with a much longer shelf life.  This makes them suitable for much longer term storage, so you have inexpensive food when prices are outrageous, a broader range of foods all year long, and if you’re a prepper, sufficient stock and supplies for years of independence from the grid.

Freeze Dryers are known for preparing food that is stable for the long term.  The vacuum system is much better at removing moisture than just heating something into submission.  It provides a crispy, light texture, preserves color, flavor, and nutrients, and the resulting product lasts nearly forever.  The biggest exceptions are high sugar and high fat foods, which neither system handles well, but knowing that in advance makes decisions easy as to what to attempt to preserve.

As an interesting side note, a package of a dozen ice cream sandwiches may cost a couple of dollars at the grocery store, but once freeze dried, make highly desirable items at a roadside stand, in a shop, or just for your own family’s consumption.  Each one could sell for the price of a whole box and people would delight in them.  You could turn such a thing into a profitable side business, which will pay for your freeze dryer much faster than using it just for yourself!  Besides, you can’t make candies in a dehydrator, but the freeze dryer just lends itself to the process…

And—in our humble opinion—dehydrated banana chips are like trying to eat a plastic poker chip, whereas freeze-dried bananas are a light, tasty, delicious treat that the whole family loves while providing essential potassium for the diet.

Check out Stay Fresh Freeze Dryers.