The biochemistry of cocoa flavor - A holistic analysis of its development along the processing chain

Abstract

The seeds of the cacao tree Theobroma cacao L. are the key ingredient of chocolate (Codex Alimentarius, 1981). They have a unique and complex flavor profile. Up to 87 descriptors can be distinguished (Januszewska et al., 2018). Beside the typical chocolate aroma, floral, fruity and nutty aroma notes may occur. Regarding taste attributes, typical cocoa bitterness and acidity are of key importance. A pleasant, mouth-filling astringency does complete the typical flavor characteristics. These attributes can be more or less intense, or even absent as in the case of floral, fruity and nutty notes, resulting in a great diversity in the flavor profile between countries, regions and even plantations (sukha et al., 2007). This diversity depends on a network of multiple interacting factors along the processing chain, from the genetic background of the cacao trees, seed physiology and climatic conditions over fermentation, drying and roasting up to chocolate ingredients such as sugar (Andersson et al., 2006; Afoakwa et al., 2008; muñoz et al., 2019). The purpose of this review is to analyze the current knowledge about the impact of these factors and their interaction on the composition of taste- and aroma-active substances as well as respective precursors and how specific flavor profiles can be explained through them. Gaps in research as well as potential applications in cocoa processing and chocolate manufacturing are discussed.