Guide to Dehydration

My entry into food dehydration was through my love of foraging. Our woods are full of bolete mushrooms, relatives of the porcini. When eaten fresh, they are slimy. When dried and rehydrated, they sing.

My initial attempts at dehydrating were in the bottom of my oven. At the lowest heat, especially in a fan oven, I dried mushrooms, tomatoes and herbs with success…until someone would turn the oven on blast, burning my preserves to a crisp. I’ve since bought a dehydrator, but you can easily dehydrate without one.

Dehydrating in the Oven

Turn your oven to to the lowest setting, cut your fruit and veg into ¼ inch slices, and put them in the oven on a lined sheet pan for as long as they need, usually 6 to 8 hours.

Using a Dehydrator

A food dehydrator is a small kitchen appliance that is used to dry, or dehydrate, your food. Utilizing a built-in fan and low amounts of heat, this small appliance uses a light flow of hot air to reduce the overall amount of water found in fruits, veggies, meats and other foods. Once the water is removed, the food won’t spoil as quickly as it normally would, and is also impervious to many kinds of bacteria that would otherwise grow. You want your food to be crisp when it is dehydrated, to break when bent. Thats how you know it is ready to be stored.

Additionally, food that has been properly dehydrated will continue to retain the vast majority of its original nutritional value. A food dehydrator allows you to retain all of those nutrients and vitamins within your food, but makes it more convenient for you to store and carry around with you. n

Temperature Settings For Fruits – 135F/57c

Fruits need a medium to high temperature to help dehydrate them to the correct texture. Most popular fruits will take around 7 hours to fully dehydrate at this temperature.

  • Apples: Remove core and cut into thin slices. These are a nice quick and easy snack to make.

  • Bananas: Peel, and cut into thin slices.

  • Melons: Get rid of skin and cut up into 1/2inch/ 1cm slices. Melons do take a while to dry out, taking between 9 – 18 hours in total.

  • Peaches: These are best peeled and cut into eights or quarters.

  • Pears: These can be peeled if necessary, but they must be cored and either sliced into eights or quarters.

  • Pineapple: Must be peeled and cored, then sliced.

  • Strawberries: These are quite easy to prepare, simply slice them in half.

Temperature Settings For Vegetables – 135F/57C

The thick texture of most vegetables means that they will take on average around 9/10 hours to dehydrate.

  • Carrots: Can be peeled, and should be cut no thicker than 3/8in/ 1cm slices.

  • Mushrooms: Mushrooms are very simple to prepare, and simply need to be cleaned with a thin brush before dehydration.

  • Onions: These must be peeled, and the tops must be cut off. After that they can be sliced into 1cm/3/8in slices

  • Tomatoes: These should be washed, then cut into quarters or eights, or sliced.

Temperature Settings For Jerky – 145-160F/ 62c-71C

Jerky needs a high temperature to fully dehydrate due to the density of the meat texture. In addition to this, it must also be dried at a high temperature so that bacteria cannot develop on the meat at any point. Any temperature above 140F is sufficient to prevent this. Prior to dehydrating, you must try to get as much fat as possible off the meat. Fat doesn’t dehydrate well. Salt or season as you wish. A tip here is that frozen and then thawed meat is actually easier to dehydrate than fresh meat as more water has come out.


Drying times generally vary, depending on how thickly sliced the jerky is.

Storing & Rehydrating Dehydrated Foods

During storage, be sure to protect your dehydrated foods from heat, light and moisture. Any of these in excess may shorten the shelf life of the food. Once your food is dehydrated, allow it to cool to room temperature to avoid condensation inside packaging.

For best results, we vacuum pack our veg or place them in glass jars. It sort of depends on how soon I plan to use them. Store them in a dark place though. It helps keep them fresh.

To rehydrate foods, plan to place 1 cup of food in 1 cup of hot or cool water, depending on your planned use. Once this is completed, allow up to four hours for rehydration. nUse as you would normally in your recipe. If you’re using a slow cooker to prepare your food, then just simply add your vegetables to the cooker, add the amount of water your recipe calls for and your veggies will rehydrate themselves.

Kat GoldinComment