The increase of a and b parameters was independent of the
drying temperature (Fig. 2). The relative visual yellow color
(b value) was slightly increased during drying at 45 and 60 ◦C,
and practically remained without changes during the drying at
75 ◦C. Similar results for the variation of values of parameter a
were found by Chutintrasri and Noomhorm (2007) in pineapple
puree during thermal processing at 70–110 ◦C. These authors
found that values of parameter b remained constant during
thermal processing at 70 ◦C.