I have asked many people this question. How can you tell if buttermilk has gone bad. I learned the answer today. The hard way. Just thought I would share it with you. For your own personal knowledge. If you get all your cornbread ingredients mixed up, reach into THE BACK (very important) of the fridge to get the opened buttermilk before you open the new one, pour the rest of the container of buttermilk into your ingredients, open the new jug to pour in some more, look down and their are LARGE amounts of gray green MOLD in your cornbread, you can pretty much figure out it is bad. Nuff said. P.S. This is also a good diet plan to follow. Promises to take away any and all appetite for a LONG time.