There is some soup that has been sitting on my fridge for 3 days today. I am not feeling in the mood for it but don’t want to throw it away (and there is really no room in the freezer). Could I just boil it and return it to the fridge?
Will that reset the clock on it, so to speak?
It might, but the flavor and texture might suffer. Besides, it’s not always the bacteria itself that makes you ill, but the chemicals those bacteria create while they’re munching on you soup. Boiling won’t generally destroy those. Three days in the fridge is probably pushing it for soup, which is an excellent medium for bacterial growth. Throw it out; unless it is literally the best soup in the world, it’s not worth the risk, IMO.
rats. I mean, thanks.
Strangely, your response might push me to eat it even if I don’t want it, just not to throw it away. 
If I never post again, please don’t come here with an “I told you so”
Exactly what is it that bacteria are pooping in my soup?
Is there anything you can add to soup (at the time you put it in the fridge) to retard spoilage?
Sure. About 1/2 cup of salt. 
I think the freezer is the best method, if you have space in there.
I often have this problem myself (of cooking way more food than I’ll ever eat over a period of 3 days), and I’m trying to get into the habit of immediately tupperwaring and freezing all but one or two days’ worth of soup/stew after cooking. Soups and stews freeze well, and if you put them in those little 1 quart plastic containers, are quick ready-to-serve meals or snacks from the freezer. Just zap up in the microwave and voila.
so I finally threw it away. We will never know how it was then.
Um, was the soup on top of the fridge or in it? 'Cause three days in the fridge shouldn’t be too bad, but on top if it is just asking for food poisoning.
had it been ON my fridge that would have been IN my freezer and it would have been alright, thank you very much 