Biomedical Engineering Reference
In-Depth Information
structure at the nanolevel, for example, by manipulating the extent and the
type of cross linking of protein fibrils, the texture of the food product can be
tailored to the tastes of these consumers.
5.3.2 Encapsulation and (Targeted) Delivery
In the same way as has been mentioned in Sections 5.1.2 and 5.1.3, encapsu-
lation mechanisms allow the delivery of specific nutrients where they are
most effective. Using self-assembly mechanisms, a structure can be created
that can contain specific nutrients. Depending on the type of substance on
the inside and outside, oily or watery, these structures are called either vesi-
cles or micelles. In fact, these structures have been used in the food industry
for a very long time, and also natural components of certain food products
are part of these categories of structures. Nanotechnology allows modify-
ing the wall of these structures to create new functionality, for example, to
release of the contents of the structure when a specific trigger is present.
Triggers can be a change in pH; however, the presence of certain enzymes,
present only at the desired location in the gastrointestinal tract, could also
be used to release the nutrients. This is called targeted release and can be
very effective in the delivery of nutrients necessary to maintain good health
(Weiss et al. 2006).
At the same time, these concepts can be used to encapsulate food compo-
nents that would spoil the desired characteristics of food products. Certain
ingredients are considered to be beneficial to health but have a bad taste.
When simply added to a food product in the normal way, this would spoil
the taste of the product, which, of course, is unacceptable. Certain peptides
that taste bitter and omega-3 fatty acids that can give a “fishy taste,” are
examples of this effect. By encapsulating these ingredients in a vesicle or
micelle, the ingredient can be released beyond the mouth region so as to
circumvent the experience of the taste.
Another reason to encapsulate a food ingredient is to make it more bio-
available. Encapsulation can maintain the dispersion of the material, which
increases the surface area and enables a faster exchange of molecules to the
phase in which the molecules are taken up by the organ of interest.
Finally, encapsulation is used to protect certain ingredients from the pro-
cessing conditions or to prevent them from being destroyed by other mol-
ecules in the food product. Some combinations of nutrients are essential for
the desired biological effect, but can also react with each other before con-
sumption, effectively destroying the beneficial effect. Vitamin A and iron
are examples of such a problem. With nanotechnology, new structures can
be engineered that keep the nutrients in separate compartments and pre-
vent premature reactions. These concepts will make fortification of popular
products possible, thus helping certain groups in society to maintain their
health.
