While cooking a kielbasa in a toaster oven today, I noticed that periodically there would be flashes near the heating element. At one point there was a very large, bright flash of light and pop as though a flammable gas was being detonated. Some of the ignitions I was able to see in detail. Next to the heating element a small round flame would illuminate and waver then go out. It was obvious that some lighter than air gas was rising up and upon reaching a high enough concentration, igniting.
What gas would the kielbasa be emitting? My first guess would be methane, but why would a cooked kielbasa be giving off methane?