Oral Processing of Chocolate Confectionary

Abstract

This chapter introduces the chocolate ingredients traditionally used in confectionary and chocolate manufacture and reviews the oral processing of chocolate and its relationship with chocolate sensory perception. When chocolate consumers first bite on a piece of chocolate, either with their incisors or molars, the hardness of the chocolate is sensed through the mechanoreceptors located in the oral cavity. After further chewing, the chocolate is broken down into smaller fragments. Stimulated saliva dissolves the sugar and the fat phase starts to melt. Mixing and shearing actions in the oral cavity emulsify the melted fat phase into the saliva phase. An oil-in-water emulsion stabilized with the surface-active ingredients from the chocolate formulation (e.g. milk proteins, cocoa solids and emulsifiers) is formed. Salivary protein also contributes to the stabilization of the oil–water interface. Over time, a chocolate bolus forms and a series of swallowing events follows once the chocolate boluses have developed favourable rheological properties. The swallowing action facilitates the perception of the chocolate flavour through retronasal olfaction. After swallowing, oil droplets can be retained in the oral cavity by adhering to the oral surface. The extent of this phenomenon is related to stability of the chocolate emulsion under oral conditions and contributes to the perception of mouthfeel.