Influences of matrix particle size distribution (PSD) (18, 25, 35, 50 μm) and fat content (25, 30, 35%) on flavour release of dark chocolate volatiles were quantified by static headspace gas chromatography using GC-MS. Sixty-eight (68) flavour compounds were identified comprising: alcohols, aldehydes, esters, ketones, furans, pyrans, pyrazines, pyridines, pyroles, phenols, pyrones, and thiozoles. From GC-olfactometry 2-methylpropanal, 2-methylbutanal and 3-methylbutanal had chocolate notes. With cocoa/roasted/nutty notes were: trimethyl-, tetramethyl-, 2,3-dimethyl-, 2,5-dimethyl-, 3(or 2),5-dimethyl-2(or 3)-ethyl- and 3,5(or 6)-diethyl-2-methylpyrazine and furfuralpyrrole. Compounds with fruity/floral notes included: 3,7-dimethyl-1,6-octadien-3-ol, 5-ethenyltetrahydro-R,R,5-trimethyl-cis-2-furanmethanol. Caramel-like, sweet and honey notes were conferred by: 2-phenylethanol, phenylacetaldehyde, 2-phenylethylacetate, 2,3,5-trimethyl-6-ethylpyrazine, 2-carboxaldehyde-1H-pyrrole, furancarboxaldehyde, furfuryl alcohol and 2,5-dimethyl-4-hydroxy-3(2H)furanone. There were direct relationship between fat content and 3-methylbutanal and branched pyrazines but inverse with 2-phenylethanol, furfuryl alcohol, methylpyrazine, phenylacetaldehyde, 2, 3, 5-trimethyl-6-ethylpyrazine and 2-carboxaldehyde-1-H-pyrrole. Particle size influenced higher alcohols, aldehydes, esters, ketones and pyrazines concentrations at all fat contents. A multivariate product space suggested flavour effects of the interacting factors.
- flavour volatiles,
- flavour release,
- acetic acid,
- particle size distribution,
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