3.3.3.3. Aldehydes. Aldehydes were detected in the pulp and nib fractions
of unfermented beans. Their levels increased about 9 fold in the pulp but
less than 2 fold in the nibs during fermentations in the absence or presence
of nisin + lysozyme (Fig. 6e, f). No differences (p N 0.05) in the concentrations
of these aldehydes in the pulps or nibs were found between
fermentations in the absence and presence of nisin + lysozyme. The two
main aldehydes in the pulp were benzaldehyde (69–73%) and phenyl
acetaldehyde (19–20.5%), with the values in brackets corresponding to
the concentrations found at the end of fermentations. Three main aldehydes
in the nibs were benzaldehyde, phenyl acetaldehyde and hexanal
and their relative amounts in roasted nibs of both fermentations were in
the range of 67–69%, 16–17% and 16–18%, respectively