I was frying some donuts tonight, and I noticed the oil looked sort of cloudy. It was cottonseed oil, and I decided that since its not the highest quality oil, and it was the only thing i had that was possible to fry with, it was worth trying a little bit. Once the oil got to temp, it seemed to have cleared up (sorry for sounding like a weather forecast here). The food came out fine.
My question: This has been sitting in the pantry for a few months? How would I know if oil is bad?