In our foods class Wednesday, a student made an egg white foam in the usual way with some cream of tartar added. She beat the whites in a stainless steel mixing bowl. The whites turned an unappetizing gray color and exuded a grayish liquid. Anyone know what might cause this? Reaction with the bowl?
Normally that's caused by using an aluminum bowl. Are you really, really sure it was a SS bowl?
Leah is 100% correct. Egg whites in an aluminum (or wood) bowl is a no-no we learned in 7th grade home ec! Of course, back then we also learned how to rotisserie a brontasaurus.
Copper is ideal for beating egg whites. No cream of tartar needed. Cream of tartar should be used when using a SS or glass bowl.