If you freeze and later melt egg whites would they still be suitable to whip I read all the very useful answers to this question
Can raw eggs be frozen?   

But my question is a bit different:

When making anything that needs whipped egg whites, the condition (cleanness/pusity) of utensile and the egg whites is essential. I wanted to know if I freeze egg whites would I be able to melt and whip them later?
Yes, quite well -- I have personally made successful angel food cakes with frozen whites -- but if volume matters, they will not quite reach the maximal height of fresh whites (say, loss of 5-10%), and achieving peaks will take a little longer whipping time than normal.