Well, most of us face this problem with butter milk or curds. When you feel like having a cup of buttermilk, its in the refrigerator, so its too cold for you to drink it comfortably. But, if you leave the yogurt or buttermilk outside the refrigerator it becomes sour and again you cannot enjoy your cup of buttermilk. Here is an easy way to help you keep the yogurt or buttermilk outside the refrigerator and yet preventing it from becoming sour. Just put a piece of Banana leaf inside the curd or buttermilk when you wish to keep it out or when there is a power cut for a very long time. Your curd will remain fresh and tasty!!