Recently browsing a certain online website I've discovered the cost of food dehydrators has fallen considerably since they first came to market. Realising that I may incur the wrath of my other half if I purchase yet another "White elephant" kitchen appliance, what are they most useful for in the domestic kitchen? It is clear that they can be used to produce dried fruit, which is then eaten all by itself. Are there any uses beyond that, which may make them more versatile?
I've got one, and I don't use it much.
Dehydrating food is worth it if you have a surplus of suitable homegrown or cheap local produce, or if you particularly want dehydrated food for some reason (portable snack probably). If your oven goes cool enough you can dehydrate in that, except the fumes from dehydrating chillies make it worthwhile to do that outside.
Dehydrators are rather bulky, so mine ends up stored in the attic, which is partly why I don't use it often.
We now have the Airfryer/toaster oven/dehydrator.
The dehydrator function is used most often to get the zucchini slices dry enough to make keto lasagna that won't be soupy without having to salt it and deal with the mess and extra work that involves. We have also made some really delicious beef jerky. Sadly it was too tasty and disappeared very quickly.
For Christmas I dried a large amount of thyme, sage and rosemary that was then blended to a nice powder and mixed with 5lbs of salt for a lovely herb salt. It is perfect with chicken soup. We are needing to do this again as it went over so well.
We are loving the Airfryer/toaster/dehydrator and use it daily. Ours sits on top of the microwave so it doesn't use anymore counter space. I was successful in talking my boss (nanny/cook) into getting one of these instead of a regular air fryer and he has been very happy. I hope any of this is helpful.
I use mine in patisserie, for making concentrated food puree. I use this concentrate for flavoring different creamy substances such as buttercream, pudding, pannacotta, etc.
The reason I do it is that, if you want your buttercream to have a fruit taste, you cannot simply put the raw fruit in, it has too much water. Jam and other preserves are an option, but they bring in too much sugar, and don't taste like the original. Similarly, cooking out the water at high heat also produces a taste very different from raw. Ideally, one can use freeze-dried fruit powder, but it's difficult to source and very expensive.
The solution I use is to start a fruit leather process, but to inspect it every hour or so and mix-and-spread the fruit mass with a spatula so it doesn't make a skin. I stop when the result is at the desired thickness - still miscible, but with as little water left as possible - and fold it in in my buttercream. This produces lovely aromatic results, and "I used real fruit" bragging rights.
Long term storage is one reason to dehydrate. There are others…jerky…fruit leather, dried fruit and tomatoes…all not necessarily long term situations. There are other creative culinary applications…dehydrated olives…working with methocel, for example. Is it worthwhile? Only you can answer the question. I use mine 6-8 times a year. Have had it for many years. Just another tool in the toolbox.
You can make black garlic in a food dehydrator, here's as video from Bon Appetit on it. While it's delicious, it's also really pricey if you buy it from a specialty store - while garlic itself is often dirt cheap. Maybe you can convince your other half that you can finance the purchase by selling black garlic? :)