probe the center with a toothpick or wire cake
tester, which should come out clean of any
batter or crumb particles.
Baking a cake. Left: A typical cake batter
includes starch granules from flour, egg
proteins that coagulate when heated, and gas
bubbles incorporated during mixing, all
swimming in a syrup of water and sugar.
(Most cakes include some form of fat, which is
not shown here for the sake of clarity.)
Center: When the mix is heated, the gas
bubbles expand, causing the mix to rise. At the
same time, the proteins begin to unfold and
the starch granules begin to absorb water and
swell. Right: At the end of baking, the fluid
batter has set into a porous solid, thanks to