2.12. Physico-Chemical Characterization of New Chocolate Textures
Bayés-García, L.; Calvet, T. *; Cuevas-Diarte, M.A.; Rovira, E.; Sato, K.; Ueno, S.
Chocolate is made up of cocoa butter (CB) crystals as a continuous body, in which tiny particles of sugar, cacao mass, and other ingredients are dispersed. Sharp melting and a quick release of flavor and sweetness/bitterness are determined by the melting behavior of CB crystals.
Cocoa butter exhibits six different polymorphic forms, referred to as I–VI. Among them, form V is industrially promoted through tempering processes, as this polymorph provides the desired melting, textural, and mouth-feel characteristics of chocolate.
Dynamic thermal treatments are highly significant in obtaining specific polymorphic forms of lipids. In this study, we examined the influences of dynamic thermal treatments on the development of new textures of chocolate revealing a soft mouth-feel (velvet effect), which can be obtained by tailoring rapid cooling and subsequent heating treatments. Fluidized chocolate (tempered mixture of chocolate and cocoa butter) was sprayed on two different substrates (metal and tempered chocolate) at different substrate temperatures (4 ˝C, 12 ˝C, 16 ˝C and 18 ˝C). Polymorphic crystallization and transformation was monitored in situ by using laboratory-scale X-ray diffraction.
Thermal treatments enabled the formation of thin layers of cocoa butter crystals with much smaller particle sizes and a low melting point compared to normally tempered chocolate, leading to the creation of a soft mouth-feeling.
The results confirmed the template effect caused by the substrate of chocolate, as polymorphic transformations occurred more rapidly than metallic substrates.