Chemistry Reference
In-Depth Information
Fig. 10.4
Designed gel beads with included oil droplets to control flavour release of oil-
soluble flavours. The photomicrograph shows oil droplets (the small white droplets) inside
an alginate gel beads (which were designed to be soft and elastic) within a continuous
aqueous phase (scale bar is 100
µ
m).
this experiment, a subject is asked to chew a food while the headspace
within their nose is removed and analysed for the aroma compounds in
real time.
An important aspect that emerges from this type of study is that the
mouth is a mixer, which dilutes and mixes to a scale of about 10 µm.
With this as background knowledge, it is possible to design and modify
the release of tastes and flavours from foods. This requires the researcher
to think about the mixing dimensions and how to build structures that
can change these mixing dimensions. An example of how this can work
can be illustrated for low-fat products. It has been reported (Malone
et al
., 2003b) that the flavour release of a 3% fat emulsion can match
a 40% fat emulsion if the fat is included inside gel beads with di-
mensions of 100 or greater microns (Fig. 10.4). Flavour release from
the fat droplets is then delayed as it needs to be transported to the
edge of the gel bead before it can enter the saliva and ultimately the
head space. This causes the flavour to be released more gradually
and gives the impression of the product having a much greater fat
content.
It has been proposed (Vliet
et al
., 2009) that particles of food broken
down during the mastication process can not only form a bolus by
adhering to one another, but can also adhere to the oral mucosa and
stay in the oral cavity after the bolus has been swallowed. The same
situation is also likely to occur with liquid that could be excluded from
