Milk Proteins and Fat

Milk proteins thicken candy body and, because they brown easily, add a rich flavor to caramels and fudge. The casein proteins contribute to a chewy body, whey proteins to browning and flavor development, and both help emulsify and stabilize butterfat droplets. Butterfat lends smoothness and moistness to butterscotch, caramel, toffee, and fudge, and reduces the tendency of chewy candies to stick to the teeth. Because milk proteins curdle in acid conditions, and caramelization and browning reactions generate acids, candies that include milk solids are sometimes neutralized with baking soda. The reaction between acids and baking soda generates bubbles of carbon dioxide, so such candies may be filled with small bubbles that give them a more fragile texture, less chewy or hard or clinging.