browning During the first stage, the batter expands to its full volume As the batter temperature rises, the gases in the air cells expand, chemical leavening releases carbon dioxide, and beginning around 140ºF/60ºC, water vapor begins to form and expand the air cells even further During the second stage of cake baking, the risen batter is set into its permanent shape by the oven heat Beginning around 180ºF/80ºC, the egg proteins coagulate, and starch granules absorb water, swell, and gelate The actual setting temperature depends strongly on the proportion of sugar, which delays both protein coagulation and starch swelling; in a highratio cake, the starch may not gelate until close to 212ºF/100ºC In the last stage, batter solidification is completed, flavor-enhancing browning reactions take place in the nowdried surface, and the cake often shrinks slightly, an indication that it should be taken out of the oven Another test of doneness is to 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 ... 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... 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. ..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