A question about grated potatoes used in the making of potato pancakes.?!
Yes, there is a way to do this, restaurants grate their potatoes up to 2 days in advance. This is how its done:
Peel the potatoes an cut them in half. As you are working, place the peeled cut potatoes in cold water. This will keep them from turning black.
Boil a pot of water on the stove. Once the water starts boiling, drop the potatoes in. Set an egg timer for 8 minutes. Pull them out of the boiling water and let them drain in a colander. Place them in the fridge and cool them completely. Do not cover them until they are cold. Once they are cold, you can grate them. I guarantee, they will not turn black. This method is called "blanching". It sets the color of vegetables.
Note: The blanching time mentioned above may not be totally accurate. It depends on the size of the potatoes. You do not want the potato cooked all the way through. Cook them roughly al dente. A knife blade inserted into the potato should go through easily but meet some resistance. With practice, you will determine the right amount of blanching time for the size of potato you cut.
Just get a squirt or two of lemon juice and put it all over the potatoes. Make sure it's just enough to cover them and not extra. When you are ready to make them, you can leave the juice on or rinse it off, depending on whether you think the flavor will go with the rest of the dish or not.
Grate the potatoes into a bowl of ice water, and simply drain them & roll them up in a tea-towel to dry before using them.