Although melting might play an important role in aroma release
and flavour perception, it is not a sufficiently strong parameter to
explain the flavour delivery of samples. When subject do not bite
the chocolate shape and let it melt in mouth, free circulating air in
the mouth may also play an important role in aroma release. The
aroma compounds which are released, while the shape is melting,
should freely circulate in order to reach the olfactory receptors
located in the nasal cavity. If the shape is perfectly adapted to the
mouth, aroma compounds could remain entrapped resulting in
none of the stimuli reaching the olfactory receptors during melting.
Therefore, it is suggested that the open void volume, i.e. the volume
in the mouth, which is available for freely circulating air once the
piece of chocolate is in the mouth, may also be a key driver to
increase flavour release and thus boost flavour perception (Fig. 9).
In other words, flavour release and flavour perception might be
enhanced not only when a shape melts at an optimum rate to
release a maximum amount of aroma compounds but also when
the shape allows an important volume for freely circulating air in
the mouth.