Meet the woman on a mission to change America's mind about room-temperature butter. Like many people, Joelle Mertzel , a mom and resident in Los Angeles, California, always thought butter should be kept in the fridge . After all, it's a dairy product and the label says, "Keep refrigerated." Plus, it's refrigerated in cases in the store. The logic follows. Several years ago, she left a stick out on the counter, only to find it significantly more enjoyable at room temperature.