Methods for food shelf life determination and prediction - Oxidation in Foods and Beverages and Antioxidant Applications - page 196

In this chapter, shelf life assessment strategies of foods and beverages
susceptible to oxidation during their life will be discussed. We will focus on the
definition of the acceptability limit described by the proper oxidative indicator
as well as possible methodologies for shelf life testing. In particular, methods of
shelf life evaluation under actual storage conditions and methods of shelf life
prediction based on exploitation of proper environmental factors able to
accelerate oxidation will be illustrated with reference to uncertainties and
possible risks arising during shelf life assessment.
9.2 Shelf life assessment strategies
The adoption of a systematic approach for shelf life determination is necessary
to obtain a cost-effective experimental design. Figure 9.1 schematically shows
the possible strategies that can be pursued to assess the shelf life of foods
undergoing oxidative reactions. The first step implies the definition of the
acceptability limit, defined as the quality level discriminating products that are
still acceptable for consumption from the no more acceptable ones. Following
this, the proper oxidative indicator should be identified before proceeding to
shelf life testing, which allows one to compute/predict the product shelf life
through kinetic modelling. Shelf life testing can be performed under actual or
accelerated storage conditions. The former is based on the direct measure of
shelf life under storage conditions simulating those actually experienced by the
product. This approach can be easily used when quality decay occurs in rather
short times (i.e., perishable foods). Generally, this is not the case of foods
undergoing oxidation. The prediction of long-term shelf life is traditionally
obtained by accelerating shelf life experiments performing stability tests under
environmental conditions able to speed up quality deterioration. After the
identification of the most suitable accelerating factor, the oxidation kinetics
Fig. 9.1 Strategies for shelf life testing of foods undergoing oxidative reactions.