German smells

Smells are different here. I have never had a problem with sewer or rot smells in any home in the States. But in Germany, it is just part of life. Garbage smells worse, pipes smell funny, and sometimes we get a mystery smell of death in our refrigerator. We have a refrigerator bigger than most here, but it is still smaller than an American one. Anyway, we usually have very little real food (besides the ketchup, salad dressing, and jar of pickle-type stuff). We grocery shop about every other day and so we regularly cycle through the food. Anyway, yesterday morning we opened the refrigerator to get the milk out and were hit with a wave of stink that I cannot even describe. It permeated the whole house in a matter of seconds. It was awful. Obviously, we didn't have time to clean it out right then, so we just plugged our noses to put the milk back and decided to attack it when we got home.
The idea of cleaning out the refrigerator hung over me all day, the memory of the smell making me wince whenever I thought about it. I was mentally calculating the value of the contents of the refrigerator, and I had decided that I was willing to throw everything away. So, we slowly started taking things out, giving them the sniff test. Eventually, we had taken everything out and nothing smelled. We checked the freezer and still nothing! I decided to be extra sure and throw out the leftover taco meat and the two chicken breasts I was saving for dinner. Better safe then sorry. I even threw out the baking soda that I keep in the refrigerator. The refrigerator was empty. We took out the shelves and cleaned them and still the smell.
So, I boiled some lemons and put the bowl of lemon water in the refrigerator and it helped a little bit. But there is still residual smell. The refrigerator has never been cleaner and there is a funky smell.
I woke up this morning and I thought I smelled it... but I am pretty sure that was a psychological thing. The smell is mostly gone in the refrigerator, but now the whole kitchen smells. We took out the garbage and I am hoping that magically the smell will be gone.
The only redeeming factor is that everyone seems to get these mystery smells. in their refrigerators, hallways, showers. I am sure it has something to do with 500 year old houses and no garbage disposals. Maybe the lack of Lysol is a contributing factor.
-L