Chapter 4: The Role of Bubbles in the Development of Food Structure

Creating aerated food structure is a challenge in culinary art, but creating such structures consistently at an industrial scale is an engineering challenge. Bubbles add novelty and versatility to the visual appearance and mouthfeel of foods. The foaminess of cappuccino, the sponginess of bread, and the brittleness or creaminess of aerated chocolates may be attributed to the formation of foam/bubble microstructures. This chapter addresses the development of bubble-containing structures in three specific food systems covering a wide spectrum of rheological behaviors exhibited: milk, chocolate, and bread. The characteristics of bubble-containing structures in milk (foamability, foam stability, overrun), aerated chocolates (density, gas holdup, bubble sizes), and dough and bread (gas-free density, specific volume, void fraction, bubble size and number distribution) are discussed and related to the process parameters, which led to the formation of the structure.