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

Q(A)= k A exp (- E A
RT ) t (49)
and if Y=Q(A)/k A then the above equation can be written as
lnY= -1
RT E A + lnt (50)
i.e a plot of lnY vs E A of different food systems gives a straight line. For a particular
variable time-temperature distribution it is proposed that a unique point (T e ,t e ) is defined
from the slope and intercept of Eq.(50). This would allow calculation of the quality change
in a food system of known E A from the measured change of two (at least) other food
systems (or TTI) subjected to the same time -temperature conditions. It has been recently
argued that this approach is only valid for isothermal conditions (Maesmans et al., 1995).
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