Chemistry Reference
In-Depth Information
cryogels was that the ice formed caused the polymer network into large
aggregates with large pores between them.
One of the main objectives for self-structuring is that the structure
produced to stop gastric emptying must eventually be removed from the
stomach to allow the next regular meal to be consumed. From the work
reported on gellan, it seems that aggregation caused the gel strength to
decrease as the pH goes below 3 and that the gel became a sponge-like
structure. This type of behaviour is potentially very important when
materials are being designed for self-structuring in the human stomach.
A gelling system that responds to acid to produce a strong elastic gel
and then changes structure as the acidity drops below pH 2 to give a
sponge-like structure could potentially lead to system that gives fullness
originally and then allow compression and compaction as the stomach
empties after digestion of the meal.
10.4
CONCLUSIONS
As this review has demonstrated, the use of practical rheology can help
in formulating healthy everyday foods, as long as the techniques are
used in combination and as tools to understand how microstructures
can be developed to give specific performance. By doing this, it is
likely that significant progress will be made in the next few years in
the development of healthier foods that fit into a normal everyday diet.
This is most likely to be for self-structuring systems for manipulation
of eating patterns, the use of tribology to understand the performance of
materials in the mouth and how consumers respond to reformulation of
foods, and in the development of duplex emulsions and their material
properties. The latter has promised such potential in the past but never
delivered due to production and stabilisation issues. However, recent
advances seem to offer hope for their future use in everyday foods.
REFERENCES
Aguilera, J.M. and Lillford, P.J. (2007)
Food Materials Science: Principles and Practice
(Food Engineering Series)
, 1st Edition. New York: Springer.
Akhtar, M., Stenzel, J., Murray, B.S. and Dickinson, E. (2005) Factors affecting
the perception of creaminess of oil-in-water emulsions.
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521-526.
Akhtar, M., Murray, B.S. and Dickinson, E. (2006) Perception of creaminess of model oil-
in-water dairy emulsions: Influence of the shear-thinning nature of a viscosity-controlling
hydrocolloid.
Food Hydrocolloids
20
(6), 839-847.
Andrews, G.P., Laverty, T.P. and Jones, D.S. (2009) Mucoadhesive polymeric platforms
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