Biomedical Engineering Reference
In-Depth Information
10.3
Challenges
No single processing technology is complete and there are always positive and
negative attributes with each and every technology. Similar is the case with minimal
processing techniques too and all the pros and cons should be kept in the mind while
application of these technologies in meat and meat products as well as seafood. The
main challenges associated with them can be summarized as under:
Microbiological safety of
sous vide
processed meat and poultry products has
been a matter of apprehension especially the survival and potential growth of
psychrotrophic foodborne pathogens and spore-forming organisms including
C. botulinum
that could survive the mild heat treatment and potential germination
and outgrowth during storage (Hyytiä-Trees et al.
2000
). However, a survey of
commercially available
sous vide
products concluded that the health risks associ-
ated with these products are quite low as long as very low storage temperatures
are maintained (Nissen et al.
2002
).
The application and understanding of infrared heating in food processing is still
in its infancy (Krishnamurthy et al.
2008b
). Infrared treatment of meat and meat
product can affect their colour. Infrared heat-treated turkey samples were slightly
darker than the controls after treatments, however refrigerated storage for an
hour resulted in no signifi cant difference in colour values (Huang
2004
). Infrared
also has low penetration power and conductivity in solid foods, so heating may
require more time. Thus it can be combined with other techniques like micro-
wave heating to achieve the desired attributes.
Development of hot and cold spots is sometimes linked with microwave heating that
depend on the parameters such as product's geometry, composition, dielectric prop-
erties and packaging. This could be controlled by the use of vapour inserted in the
oven cavity to distribute the heat and packaging with valves (Lacroix et al.
2000
).
Most of the problems related to ohmic heating are due to the electrical nature of
the food treated. Compounds with poor conductivity, especially the fat in meat
products, do not generate heat as the same rate than muscle thus creating a cold
spot (Shirsat et al.
2004b
). Geometry factors such as the size of the meat pieces
are also important and limit the use of the technology. Other composition
parameters such as the acidity may affect the best working conditions of the
electrodes and reduce the effi ciency of the system. Therefore product composi-
tion has to be adapted to the technology (Zuber
1999
). Although ohmic cooking
procedures are quite mild, there is a risk of toxicological changes in meat and
meat products because of direct contact with the electrodes. The effects of
ohmic cooking on quality of meat products should also be verifi ed by examin-
ing different types of meat products in a wide range of ohmic cooking condi-
tions (Yildiz-Turp et al.
2013
).
During high pressure processing, temperature of food material increases as a
result of physical compression. This temperature increase may have an effect on
various characteristics of the product like gelling of food components, stability of
proteins, migration of fat, etc. The effectiveness of HPP is greatly infl uenced by
