What eggs do in cake
Raw egg proteins are folded into tight coils. Heat unfolds them, and they bond into a net that sets around the air bubbles and starch in the batter. That net is why a cake holds its shape and slices clean.
Why recipes say room temperature
Cold eggs chill creamed butter back to firm, so the fat and water split and the batter looks curdled. Room-temperature eggs blend in smoothly and whip to more volume. In a hurry, soak whole eggs in warm tap water for a few minutes.
Test yourself
Questions from the interactive lesson, with the answer and the why.
What lets a cake hold its shape after it cools?
Egg proteins bond into a net. Heated proteins link up and set around the bubbles, holding the crumb in place.
True or false: Egg yolks, which carry fat and an emulsifier called lecithin, make a cake crumb softer than whites alone.
True. Yolk fat and lecithin soften the crumb and help the batter mix smoothly.
What went wrong? You beat fridge-cold eggs into creamed butter and sugar. The batter turns lumpy and looks split.
Cold eggs chilled the butter, so fat and water split. Firming butter can't hold the egg's water in an emulsion, so the batter breaks.
Fill the blank: In the oven, egg proteins unfold and ___ to each other, forming the net that sets the cake.
In the oven, egg proteins unfold and bond to each other, forming the net that sets the cake. Unfolded proteins link up and form the net that holds the crumb.
