the handbook of food engineering practice crc press chapter 10 ...

action or dispute. Sometimes consumers can be "trained" to accept lower standard
products by being exposed to products of gradually slipping quality. That makes the need
of alternative ways of assessing quality apparent (Herborg, 1985).
Chemical, microbiological and physical tests are being used widely in the study
of food quality. Characteristics used by the consumer for evaluation of a product, such as
flavor, color and textural properties can be measured instrumentally or chemically. The
study of the chemical and biological reactions and physical changes that occur in the food
during and after processing allows the recognition of the ones that are most important to its
safety, integrity and overall quality. Physicochemical or microbiological parameters can be
used to quantitatively assess quality. The values of these parameters can be correlated to
sensory results for the same food and a limit that corresponds to the lowest acceptable
organoleptic quality can be set. However, caution should be drawn to the fact that
correlation of values of individual chemical parameters to sensory data is often not
straightforward because overall organoleptic quality is a composite of a number of
changing factors (Trant et al., 1981). The relative contribution of each factor to the overall
quality may vary at different levels of quality or at different storage conditions.
Despite the discussed difficulties in defining and evaluating quality and
determining shelf life of a food, a lot of progress has been made towards a scientific and
generally accepted approach. It is an area of continuous and extensive research. An indepth
study of the different deteriorative mechanisms that occur in a food system and
systematic analysis and interpretation of the results lead to more meaningful and
objectively measurable ways of assessing food quality and determining shelf life. Proper
application of chemical kinetic principles to food quality loss is essential for efficiently
designing appropriate tests and analyzing the obtained results.
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