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

10.4 EXAMPLES OF APPLICATION OF KINETIC MODELING
10.4.1. Kinetic calculations
Two examples highlighted, are based on simulated model systems (Saguy and Cohen,
1990) describing a nonenzymatic browning reaction (Table 6; Figure 9) and thiamin
retention (Table 7; Figure 10). The data was generated assuming the values of the energy
of activation, E A /R, the rate constant defined at a reference temperature, k ref and the initial
concentration A o . A random error of +/- 5% was introduced to account for realistic
experimental conditions and error. It is worth noting that in both examples, the reference
temperature, T ref , was chosen as 300 K. As pointed out previously, this transformtaion is
important for improving the stability during numerical integration and for nonlinear
parameter estimation. The transformation is also recommended since the parameters are
highly co-linear and are not easily regressed directly (Cohen and Saguy, 1985; Haralampu
et al., 1985; Nelson, 1983).
Linear and nonlinear subroutines were utilized to derive the regression
coefficients and analyses (BMDP1R and BMDPAR; Dixon, 1989).
Figure 9.
Nonenzymatic browning of a model system as a function of
storage temperature (zero order reaction).
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