Does microwaving salmon soup exacerbate albumin release, why or what is this excessive white stuff?

If I immerse salmon in a bowel of water and microwave it I notice that a white froth quickly rises and builds to the top of the water. After the salmon is cooked there is an excessive amount of white frothy stuff that i need to use a sieve to remove. The froth itself tastes ghastly. When I cook in a pot on the hob however the soup water doesnt become frothy, rather it looks clear.

1. Is this albumin?
2. Why does microwaving specifically give this result but not when cooking the soup on a hob.
3. I notice alaska sockeye salmon produces far less forth even when in the microwave. Know why this is, does it have anything to do with sockeye being wild caught rather than farmed?

In relation to Jefromis comment, I cannot see inside the microwave though it may not even boil. I say that because water is almost to top of bowel and after removing i dont see traces of water from boiling. After microwaving glass bowl is too hot to touch so maybe the water\glass is very hot though not boiled. in case of hob, i bring to boil, add salmon then simmer for 5-10 minutes, no foaming occurs like the microwave.