Ha, I read a spice shop owner's blog post about this once and she said the dollar store stuff sits in warehouses way longer before it even hits the shelf. That's why the cumin was already dead on arrival. The cheap jars are also smaller, so you're paying more per ounce than you'd think. I've had better luck with the big bags from the Indian grocery, they turn over fast so it's actually fresh.

Tbh it's usually way before 50, around 20 for most.

Walnut does nothing for dark stains.