I've heard of the front milk being kind of "bluish" because of the protein, and when pumping, I find that the first few ounces to come out are bluish-green. At first I blamed it on my spinach-loving self, but then I read about the protein factor. If I completely empty my breasts, the hind milk is very white and creamy, and it usually offsets the blue/green color. I also read that eating food with a lot of color, such as blueberries, etc, can affect milk color. Either way, I am sure it is absolutely nothing to worry about.