What to put in cut potatoes prevent them from changing colour?

Lemon juice, vinegar, or other acidic solutions: The acid in these solutions helps to slow down the enzymatic browning reaction. You can either soak the cut potatoes in a solution of water and lemon juice or vinegar before cooking, or brush them with the solution after they have been cut.

Salt: Salt also helps to prevent potatoes from turning brown. You can either sprinkle the salt on the cut potatoes before cooking, or boil them in salted water.

Cooking the potatoes quickly: The longer the potatoes are exposed to heat, the more likely they are to turn brown. Therefore, it is important to cook them quickly over high heat. For example, you can roast them in the oven, fry them in a pan, or boil them in water.

Storing the potatoes in a cool, dark place: After the potatoes have been cooked, store them in a cool, dark place. This will help to prevent them from turning brown.