What would cause a "Parmesan cheese" like odor in my cottage?

Thank you for your answer. We did have the hurricane this past summer. The light were out for several days. Had my neighbor, throw everything out of my fridge. It was clean and empty when I got here. Its a newer fridge, (Kenmore) side by side, I couldnt find how to check the the evaporation tray. Called sears, they suggested I get a service call, For $89. I said I would figure it out myself. I'm 75 years old, widow. But I did it. Took the lower back cardboard cover off, could see the tray, but lots of wires from the back. So I forced the front grill off, and there it was behind the water dispenser filter. Couldnt pull it out. So I filled my turkey baster with clorox clean up, and squirted into the tray. Right now, I think that was it, and explains why, I would smell it in the front room sometimes. Probably when the fan kicked on. I will wait now, for someone to visit that can get down on their knees to see it better. Thank you again.