Sensory Characterization of Single-Origin Dark Chocolates from Wild Amazonian Cacao

Abstract

The sensory diversity of Amazonian wild cacao (Theobroma cacao L.) remains largely undocumented. While cultivated cacao has been extensively characterized, little is known about how non-domesticated Amazonian cacao expresses aroma, flavor, and mouthfeel in finished chocolate. This exploratory study investigated the sensory profiles of commercial single-origin dark chocolates produced from wild cacao sourced from regions of the Amazon rainforest in Brazil, Bolivia, Peru, and Venezuela. Panelists (n = 8, 7 women) completed five 2-hour sessions encompassing lexicon development and descriptive analysis to standardize attribute definitions and use of a 15-point intensity scale. Panelists subsequently participated in four evaluation sessions to assess nineteen commercial dark chocolates (17 wild cacao chocolates and 2 controls; cocoa percentage from 66% to 100%) and rated the intensity of 20 attributes in terms of mouthfeel, aroma, and flavor. Sensory data was collected in Compusense® and statistical analyses were conducted in R/RStudio (α=0.05). Sensory profiles of the chocolates were generated from the mean intensity ratings for each attribute. Means were analyzed using a three-way ANOVA (product x judge x replicate) with Tukey's HSD for post-hoc comparisons. Multivariate differences among products were assessed using MANOVA and Principal component analysis (PCA) was applied to visualize relationships among samples and identify attributes contributing most strongly to variation. Thirteen sensory attributes (bitterness, sweetness, acidity, astringency, graininess, creaminess, brittleness, coating, chocolate flavor, fruity flavor, vanilla flavor, cocoa aroma, and coconut aroma) differed significantly across products (p<0.05) and the wild Amazonian cacao chocolates expressed broad sensory heterogeneity. Compared to the two control chocolates, the wild Amazonian cacao samples were generally less sweet and exhibited higher bitterness, acidity, astringency and fruitier notes while the controls were characterized by greater sweetness, cocoa aroma and vanilla flavor. PCA revealed a dominant first principal component explaining 61.7% of the variance, representing a gradient from high cacao, bitter-astringent samples to sweeter creamier samples, with the controls positioned in proximity to one another and the wild cacao chocolates displaying broad dispersion. Hierarchical cluster analysis confirmed three broad sensory groupings among the 19 samples, consistent with the PCA distribution. Chocolate sensory properties are a result of complex interactions among cacao genetics, fermentation, post-harvest handling, and processing. This research supports the need to further investigate how cacao genotype diversity within the Amazon rainforest and terroir influence fine flavors and high-quality sensory characteristics in chocolate. This knowledge is vital to support current and future cacao preservation efforts, breeding for fine-flavored cocoa, sustainable production, and economic development.