Years ago, I tried to dehydrate potatoes, but I ended up with pile of black potatoes. I didn’t do my research. After getting a 10 pound bag of potatoes for $2 I decided to try again, and this time my potatoes stayed perfectly white after drying. The secret is lemon juice or citric acid, and blanching. Make certain you don’t put lemon juice or citric acid in the boiling water, however, as the potatoes will be left with a lemony flavor. These potatoes can be used in casseroles, crockpot dishes, fried into chips, and scalloped potatoes.
First and cut the potatoes in ¼ to 1/8inch slices – it will really depend on how you choose to employ the potatoes. Peeling is optional, just as the potatoes are well washed. Using a mandolin will yield even slices, allowing the potatoes to dry at the same rate. If you have a deli slicer, that’s even better, which makes quicker work of your project. But, a knife will work too.
As you peel the potatoes, put them in a dish with cold water with the juice of a lemon or citric acid.
Bring a pot to boil, and cook the potatoes for 1 minute 30 seconds.
Plunge hot potatoes into ice water with lemon juice or citric acid.
Place the potatoes in a single layer in your dehydrator and dehydrate 125 degrees until hard. My really thin slices only took 3 hours, but the time depends on thickness of the potatoes. I did some a little thicker which took 5 hours. Make sure the potato has no soft give at all. I store mine in glass jars for immediate use, and in mylar bags for long term storage.