 The brand also owns the "Rumford", "Davis", "Hearth Club" and "Royal" brands of retail baking powder, baking soda and corn starch, and the "Royal" brand of dessert mixes.The Clabber Girl name brand comes from the word "clabber", a type of sour milk.In the early 1800s, people mixed clabber with pearl ash, soda, cream of tartar, and a few other ingredients to make what we know today as baking powder.