Chemical Characterization, Gastrointestinal Motility and Sensory Evaluation of Dark Chocolate: A Nutraceutical Boosting Consumers' Health

Abstract

We performed a comprehensive study encompassing chemical characterization and sensory evaluation of two types of dark chocolate, i.e., artisanal (Choco-A) and industrial (Choco-I), as well as an evaluation of onset of gastrointestinal symptoms and gastrointestinal motility in healthy subjects fed with dark chocolate. Proteomic, lipid and metabolite analysis were performed by LC-MS/MS analysis and the total phenol content and antioxidant activity were estimated in both types of chocolate. Fifty healthy volunteers joined the study of the sensory characteristics of both types of chocolate; another 16 subjects underwent the study of gallbladder and gastric emptying by functional ultrasonography and orocecal transit time by lactulose H₂-breath test after ingestion of dark chocolate. Identification of polyphenols, amino acids and fatty acids was carried out in both types of chocolate analysed, and results confirmed their richness in polyphenols, amino acid derivatives and fatty acids (FAs) either saturated (stearic, myristic, palmitic, ecosanoic) or unsaturated (oleic and linolenic). For agreeability, Choco-A scored higher than Choco-I for smell, texture, and taste and they did not show significant differences in the gastrointestinal motility. In conclusion as for gastrointestinal motility studies, we report that the ingestion of a small amount of chocolate induced a mild gallbladder, gastric contraction and a fast transit time compared to the test meal in healthy subjects.

Keywords: chemical characterization; chocolate; high resolution mass spectrometry; nutraceutical; orocecal transit time; polyphenols; ultrasonography.

Figure 1

The diagram is shows the study design. Chemical analyses, organoleptic evaluation and clinical study of two dark chocolates compared with a standard meal (Nutridrink). Choco-A, artisanal; Choco-I, industrial.

Figure 2

Forms employed for the organoleptic evaluation of the chocolates.

Figure 3

Mean abundance (%) of the chemical profiling in chocolates.

Figure 4

Score of sensory evaluation of two chocolates. Data are expressed as means ± SEM. * p < 0.05 Choco-A vs. Choco-I.

Figure 5

Gallbladder emptying parameters in response to ingestion of chocolates and test meal. (A) Time-dependent changes of gallbladder volume as mL; (B) Residual gallbladder volume as mL; (C) Half-emptying time as min; (D) Area under emptying curve (AUC). Data are expressed as means ± SEM. * p < 0.05 vs. Choco-A and Choco-I.

Figure 6

Gastric emptying parameters in response to ingestion of chocolates and test meal. (A) Time-dependent changes of antral area as cm²; (B) Residual antral area as cm²; (C) Half-emptying time as min; (D) Area under emptying curve (AUC). Data are expressed as means ± SEM. * p < 0.05 vs. Choco-A and Choco-I.

Figure 7

Orocecal transit/colonic fermentation parameters in response to ingestion of chocolates and test meal. (A) Time-dependent changes of H₂ levels (ppm) in exhaled air; (B) Orocecal transit time (OCTT) as individual values and mean ± SEM reported below; (C) Area under H₂ curve (AUC). Data are expressed as means ± SEM. * p < 0.05 vs. Choco-A and Choco-I.