Chemistry Reference
In-Depth Information
Fig. 10.18
Compression stress/strain curves obtained for a low-fat spread (Flora) and
water-in-water emulsions (20% maltodextrin/4% gelatin/0.1 m NaCl) contained 0 or 10%
oil (emulsified with 0.5% (w/w) Tween 80, droplet size
∼
5
µ
m) using an Instron material
tester.
material properties, mouth-feel and sensory properties of a full-fat prod-
uct. An ingredient which has been used very successfully is low dextrose
equivalent maltodextrin gels, which when used in mixed biopolymer
systems can mimic the organoleptic properties (failure, melting, etc.)
and material properties (e.g. spreading, scooping, etc.) of the high-fat
products. Fig. 10.18 shows some gelatin/maltodextrin water-in-water
emulsions in which liquid oil has been added to produce a low or very
low fat spread with virtually no saturated fatty acids (SAFA). These mix-
tures were designed to have properties similar to fat-continuous spreads
(butter alternatives); as demonstrated in the figure, these water-in-water
emulsions can be constructed to give material properties very similar to
the original high-fat SAFA-containing emulsion (e.g. low-fat Flora). As
would be expected, the addition of oil has little effect, as it acts as a soft
filler. The material properties of the water-in-water emulsion depend
upon the continuous phase and, as such, depend on the bloom strength
of the gelatin which is present both as droplets in the water-in-water
emulsion and in the continuous maltodextrin phase. The major reason
that maltodextrin works in this system is that, as an oligosaccharide,
it forms aggregates which are crystalline in nature. These crystals then
interact to produce a crystal network. This network has properties that
