This process, which is called oxidation, happens because potatoes are a naturally starchy vegetable. And when exposed to oxygen, starches turn gray, brown, or even black. An oxidized potato is completely safe to eat. The process doesn't affect the flavor or texture of the vegetable.
Because you just put them into the freezer, the cell structure hasn't broken down so while the visual looks bad, they are probably still safe to eat.
Potatoes need to be pre-cooked before freezing or the texture and flavor will degrade, and the cold temperature will turn the potato black when thawed.
There is an enzyme reaction that has to take place to keep the potatoes from turning black. In the future, you'll need to cut the potatoes, placing them into water with a little lemon juice or white wine vinegar (something acidic) and then you need to blanch them by heating in water till mostly done.
However, If you do store raw potatoes in the freezer, they may last up to 10 to 12 months (more on storing potatoes later). To avoid a sweeter flavor and discoloration, blanch potatoes before refrigerating or freezing.
How to tell if frozen potatoes are no longer good? If dry spots or discolorations have developed on the frozen potatoes, freezer burn has begun to set in - this will not make the frozen potatoes unsafe to eat, but it will harm the texture and taste.
The exact color of freezer burn discoloration varies depending on the food, but freezer burn tends to look white on poultry (chicken), grayish-brown on meat (steak), white on vegetables, and icy crystals formations on ice cream.
Storing Potatoes in the Freezer
Potatoes contain enzymes that cause browning when they are left for too long—these enzymes remain active even when the potatoes are frozen. However, partially or completely cooking them helps deactivate the enzymes and prevent discoloration.
A: Almost always there are two reasons the potatoes turned black... exposure to air or oxygen and black spot bruising. As soon as the potatoes are cut I would try to get them into some sort of water and acid mixture, usually a gallon of water needs 1 tablespoon of concentrated lemon juice or white wine vinegar.
Do potatoes turn black when frozen? Often potatoes don't turn black in the freezer but turn black when thawed after being frozen. This is typically caused by exposure to oxygen and can be prevented by keeping fresh sliced or peeled potatoes submerged in water, and by blanching them before freezing.
A: Hash Browns or French fries are usually good in the freezer for 4-8 months at zero degrees F. While still cold, if they are soft to the touch that means they have lost the crispy texture you'll expect of a quick frozen potato. If this occurred over a day or two, you should be fine to heat them up.
Drain the potatoes in a colander, shaking to remove excess water. Freeze the potatoes on a sheet pan. Place the potatoes on a large baking sheet, spreading them so none touch, and slide into your freezer for 6 to 12 hours, or until each piece is frozen solid. Store the potatoes.
According to the American Journal of Potato Research: After-cooking darkening is caused by the oxidation of the ferri-chlorogenic acid in the boiled or fried potatoes. The severity of the darkening is dependent on the ratio of chlorogenic acid to citric acid concentrations in the potato tubers.
This process, which is called oxidation, happens because potatoes are a naturally starchy vegetable. And when exposed to oxygen, starches turn gray, brown, or even black. An oxidized potato is completely safe to eat. The process doesn't affect the flavor or texture of the vegetable.
You absolutely can freeze potatoes, and you should if you have an excess of spuds. But there's one important thing to remember: You should really only freeze cooked or partially cooked potatoes, as raw potatoes contain a lot of water. This water freezes and, when thawed, makes the potatoes mushy and grainy.
Mold on potatoes can vary in color and appearance, but it often appears as white, gray, green, or black spots. It may also appear as a fuzzy growth or a slimy, slippery texture on the surface of the potato.
Freezing potatoes in advance is an easy way to cut down on the holiday meal prep. When you're ready to serve them, simply fry, boil, or microwave them until fork tender — without any need to thaw them. You'll have mashed potatoes, french fries, or crispy roasted potatoes on the table in minutes.
How long do mashed potatoes last in the freezer? You can freeze mashed potatoes for up to one month. There's a good amount of liquid in the potatoes that could form ice crystals and cause freezer burn if they're frozen for longer periods of time.
According to the FSIS, freezer burn doesn't make food unsafe, but rather it makes it dry in spots which is a quality issue not food safety issue. These dry areas appear as grayish-brown spots and are caused by air coming into contact with the surface of the food.
Forgotten Leftovers and Meals
Sadly, frozen foods and meals should be eaten within three to four months, according to the USDA's Food Safety and Inspection Service. After that their quality degrades significantly. If anything has been in your freezer for more than six months, it may be time to say goodbye.
Check for soft spots, dark spots, sprouts, or green color. If the potato has little sprouts remove them, then prep potato for your dish. If there is a little green cut that off. If the potato has long spouts, is soft, wrinkled, or has lots of dark spots get rid of it.
Once frozen, the cell structure changes, resulting in a poorly textured potato that lacks flavor once thawed and then cooked. Unfortunately, the only good place for these potatoes is the bin! However, if the potatoes have been blanched then yes potatoes are good after being frozen.