Just sorting my gear out for start of the season , got a bucket of pellets left Probably 2 years old now do I bin them or use them .
The oil that would secrete out of the original Hinders elips and collect at the bottom of the bag or tub was legendary. I had some prolific catches of the Middle Trent putting some of those oily pellets in the feeder when there was a bit of water on. The Elips available today, whilst still excellent, don’t seem to secrete any like the oil the old ones did.The only pellets I've known to really go 'off' is the old Elips pellets. I had a (seemingly) sealed container of them that had doubled in size with undissolvable mold ...it was like rubber!
My rule would be ...it they look ok, and smell ok, then they're ok.