Check the expiration or use-by date
Look for mold on the surface or lid
Notice any sour, rotten, or unusual smell
Watch for pink, green, black, or fuzzy spots
Check for a swollen, leaking, or damaged container
See if the texture is extremely watery, curdled, or separated beyond normal
Taste only if it looks and smells normal
Throw it out if it has been left unrefrigerated for more than 2 hours
Discard it if the yogurt tastes bitter, rancid, or off
When in doubt, throw it out