Lots of info on the web, generally very conservative..."use no more than 3 weeks after sell-by date"
Well, I found a full can of ultra-pasteurized Reddi-Whip aerosol that has been sitting patiently in my fridge for a couple of years!
Yes, the sell-by date reads Oct 2012.
So after some research, I decided to give it a shot. The best guiding principle is "use your senses". Smells bad? Looks wrong? Tastes sour? Then throw it out. Geez, if you feel squeamish about it in the first place, don't do it.
Sprayed it into a bowl. No separation, no funky smell, no odd yellowish color. Pure white, like when it's new.
Next step: dip my finger and taste.
It tasted fine! Just goes to show that if it doesn't look moldy or gross, you should try to trust your own senses to determine if something is bad or not. In this case, it tasted bad IN NO WAY.
I've had containers of buttermilk 3-4 weeks past the expiry date still be fine.
Those expiration dates are often just a guideline...use your senses to figure out what's good and what's not.