That odd, mildly off-putting white substance that you've likely noticed coming out of your fresh-out-the-oven salmon fillets is called albumin. And besides looking a little funny, it's nothing to much worry about.
Albumin is a water-soluble protein that coagulates with heat--in other words, it's a totally natural part of the fish that solidifies into white gunk and seeps out of the muscles when the salmon's flesh heats up during the cooking process (be it oven roasting, grilling, etc.).
The best way to prevent it?
Well, the longer the salmon cooks, the more albumin is going to surface. So the key to keeping the white goo-factor to a minimum and maximize aesthetic appeal is to make sure not to over cook your salmon--which should be high on the priority list anyway. Coating the fish's surface helps too.
Here are a few of our fave ways:
Roasted Salmon with Soy-Marmalade Glaze