Scalded Milk: Then and Now

Some bread recipes call for scalding milk. What does this do?

To scald milk is to bring it to the verge of a boil (about 180 degrees), after which it must be skimmed of the thin skin that forms on top. In bread recipes, scalding has historically served two purposes: to kill harmful microbes in the milk and to break down the milk proteins that can otherwise thicken and hinder the rise of yeast. Since the advent of modern pasteurization, the risk of harmful microbes has been negated. But what about scalding's impact on yeast and rising?

To test whether scalded milk actually produces a higher rise in bread, we prepared two loaves of American-style sandwich bread, one made with scalded milk (heated to 180 degrees) and one made with milk warmed just enough to activate the yeast (to 110 degrees). The loaf made with scalded milk did have a slightly higher rise, but the loaf made with warmed milk was still very good. Since scalding introduces the possibility of killing the yeast if the baker doesn't let the hot milk cool down sufficiently (temperatures higher than 120 degrees will kill most yeast), we don't recommend this step; the small benefit isn't worth the risk.