Practically, strong thermal treatment has been used to achieve commercial sterility of vegetables. Therefore,
the kinetic parameters including reaction order, rate constant and activation energy are essential to predict the
quality loss during thermal processing. The researches on determining the discoloration of vegetables during
processing are mainly based upon quantitative analyzes of chlorophyll pigments. On the other hand, some investigators
used colorimetric parameters to determine kinetic parameters for the color changes in vegetables.
The CIE-L*a*b* system is a versatile and reliable method to assess the color of fruit and vegetables and its
changes during storage and processing (21, 22, 23). The parameters a and b express the green-red and blue-yellow
axis, respectively (23). The -a value has been used as a physical parameter to represent greenness
in color measurement (16, 24). Additionally, some other researchers (25) have monitored changes in chlorophyll
content by the ratio of -a to b value (-a/b) for canned green peas and green beans.