Biomedical Engineering Reference
In-Depth Information
5.2 Applications in Food Processing and Production
Micro- and nanotechnologies can help improve many of the processes used
in the food industry (Kampers 2007, 2009). Since virtually all food materi-
als are derived from biological substances, they consist of a hierarchy of
structures starting from the molecular and supramolecular levels through
the micro- and mezolevels to the macrolevel where the consumer experi-
ences its specific qualities and texture. To improve on the latter therefore
usually means that the underlying structural levels also need to be modi-
fied. Traditional processing of foods already makes use of this principle but
was largely derived from trial-and-error and best practices that have been
handed over from one generation to the next for centuries. They all intervene
at the macrolevel but result in structural changes also at the nanolevel. If you
cook an egg, you process it at the macroscale; however, it results in conforma-
tional changes in the proteins, which provide the desired structural change
to give the texture the consumer prefers. With the advent of nanoscience, it
is now possible to devise processes that provide much more control at the
nanolevel and therefore can result in more accurate structural changes and
new functionality. However, we will start the overview of applications in
processing and production with the improved measurement technology that
will be possible through the use of micro- and nanotechnologies.
5.2.1 Process Monitoring
Because food materials are of biological origin, they exhibit large variabilities
in structure, composition, and properties. Within one batch, the properties
can vary substantially, making it difficult to realize the structural changes
everywhere in the same way. Moreover, the physical size of a food product
in relation to the macroscopic processing also provides a challenge if precise
structural changes are desired. A turkey cooked in an oven can easily be
burned on the outside and still raw in the core. Processes in the food indus-
try must be designed in such a way that they are robust for this variability,
and centuries of optimization have provided us with a range of processes
that can be used successfully. These processes already often use sensors to
determine critical parameters. In baking bread, the oven temperature and
the time inside the oven are important parameters to monitor, and experi-
ence dictates how to use them. However, a baker also uses visual and smell
monitoring during the process and intervenes when more accurate control is
necessary. Unfortunately, this method is difficult to automate. However, with
sensors that mimic the human vision and olfactory systems, new opportuni-
ties could arise.
One of the areas of research in micro- and nanotechnologies is directed
toward the development of an electronic nose (Gardner and Bartlett 2000).
The human olfactory system employs 300-350 different receptors located in
