How to Dehydrate Bananas Without a Dehydrator
Bananas go from perfect to bruised in about a day and a half. Then someone says “I’ll make banana bread,” and 3 weeks later the freezer has 6 black bananas in it.
Drying is the other option. It takes some slicing and a low oven, and it doesn’t take a dehydrator.
How to dehydrate bananas, the short version: peel firm, ripe bananas and slice them 1/8 inch thick. Soak the slices for 10 minutes in lemon juice and water so they don’t darken, then drain them. Spread them in a single layer and dry at 140°F until they’re tough and leathery, about 6 to 10 hours. Cool them, hold them in a jar for about a week, then store.
Times and temperatures here follow the drying guides from Colorado State University, Penn State and NDSU.
What do you need to dehydrate bananas?
- Bananas. Firm and ripe. Not green, and not collapsing.
- Something for the soak: lemon juice or citric acid.
- A sharp knife. 1/8 inch is thin, so slice slowly.
- Oven racks, or cookie sheets lined with cheesecloth or curtain netting.
- An oven thermometer, and a wooden spoon to prop the door open.
- A glass jar with a lid.
How do you dehydrate bananas in the oven, step by step?
- Peel the bananas and slice them into rounds 1/8 inch thick. Keep them the same thickness so they finish together.
- Make the soak. Use one of these:
| Soak | Mix it with cold water |
|---|---|
| Lemon juice | 1 cup lemon juice plus 1 cup water |
| Citric acid | ½ teaspoon in 2 cups of water |
- Drop the slices in for 10 minutes, then lift them out gently with a slotted spoon and drain well. Banana slices are fragile, so don’t stir them around. The soak also helps kill bacteria while they dry.
- Lay them in a single layer on the racks, with no slices overlapping.
- Set the oven to its lowest setting, aiming for 140°F. Put the thermometer on the rack, prop the door open about 2 inches with the wooden spoon, and turn the fan on if you have one.
- Dry them for about 6 to 10 hours, until they’re tough and leathery.
- Near the end, turn the oven off and leave the door wide open for an hour, because fruit scorches easily right at the finish.
- Test one (see below), then let the rest cool completely.
Is your oven up to it?
Some aren’t. Set the oven to its lowest setting, put a thermometer on the rack, prop the door open, and put a fan near it if you can. If it holds 140 to 145°F, you’re fine. If it runs much hotter, the outsides of the slices harden before the middles dry, which is called case hardening.
A fan oven beats a regular one, because it moves the air. Oven drying isn’t a good idea with young children and pets around, since the door is propped open and the oven runs for hours. Got a dehydrator? Use it. It’s faster, and the method is the same.
How long does it take to dehydrate bananas?
6 to 10 hours at 140°F. A dehydrator or a fan oven is at the short end, and a regular oven is at the long end. Thickness, humidity and how many slices are crowded on a rack all move it. Go by the test, not the clock.
How do you know when dehydrated bananas are done?
They should be “tough and leathery.” That’s chewy, not crunchy.
Take a few slices out and let them cool for a few minutes, because warm fruit feels softer and wetter than it is. Then squeeze a handful. If your hand stays dry and the pieces spring apart when you let go, they’re done.
Do you have to condition dried bananas?
Yes, and it takes about a week. Some slices dry more than others, and a few damp ones in a sealed jar can grow mold. Conditioning shares the moisture around.
Pack the cooled slices loosely into a glass jar, about two-thirds full, with the lid on. Shake it once a day. If beads of moisture form on the inside of the jar, the bananas aren’t dry enough. Put them back in the oven and dry them longer.
How long do dried bananas last?
6 to 12 months in a cool, dry, dark place. Heat shortens that, and the fridge or freezer makes it last longer.
- Cool them completely first. Warm fruit sweats inside a jar.
- Use small jars, so you’re not opening the same one over and over.
- Use glass, so you can spot moisture.
- Toss anything that smells off or shows mold.
If you left the slices uncovered while drying, add one step: heat them in the oven at 160°F for 30 minutes, or freeze them at 0°F or below for 48 hours, to kill any insect eggs.
How do you use dried bananas?
Eat them as a snack, or stir them into granola or hot cereal.
Common questions
How thin should you slice bananas for drying?
1/8 inch.
What temperature do you dehydrate bananas at?
140°F. Anywhere from 140 to 150°F works in an oven.
Do you have to soak bananas before dehydrating them?
Yes, it’s part of the method. A 10-minute dip in lemon juice and water, or citric acid, keeps them from darkening.
Can you dehydrate bananas in an oven?
Yes. Use an oven that holds 140 to 150°F, with the door propped open.
Your next small step
Peel 2 bananas, not a whole hand. Slice them thin, soak them, and put them on one rack. That’s enough to find out whether you like chewy.
Drying apples too? Here is how to dehydrate apples in the oven.
Want the bigger picture on preserving in a small kitchen? Start with the free guide.
Know someone with a freezer full of black bananas? Send this their way.
Sources (each read 2026-09-21):
- Colorado State University, Drying Fruits (reviewed August 2025)
- Penn State, Let’s Preserve: Drying Fruits and Vegetables (Dehydration)
- Penn State, Dried Apples (oven and pasteurizing details, which apply to fruit drying generally)
- NDSU, Food Preservation: Drying Fruits
- National Center for Home Food Preservation (University of Georgia), Packaging and Storing Dried Foods
