Muffin pans, introduced in the mid-1800s, were an arrangement of "gem" cups fastened together by a rack. To this day, muffins are still called "gems" in many parts of the country.
For extra orange flavor, replace half of the milk with 1/2 cup of orange juice. When grating orange peel, grate only the orange part of the peel; the white part, or pith, is bitter.
Instead of using fat-free cholesterol-free egg product or egg whites, go ahead and use 1 whole egg, if you like.