Hiya, you can tell by the colour of the bar itself, if it's a nice pale honey colour then you're okay, if it's quite dark then it's off. I had 2 off ones in 2 weeks, and on tuesday night we opended 6, and they were all off. I'm giving them a wide berth at the moment as they tasted so yucky, they had a really bitter aftertaste. Only cranberry for me from now on!