The trend for total colour difference of reconstituted Gac powder
products as a result of the spray-drying process was similar to the
results for redness in terms of being significantly affected by the
inlet drying temperature; however, not by the maltodextrin concentration.
The reduction of redness, indicated by high hue angle
and low a*/b* value, is the possible explanation for an increased total
colour difference in reconstituted Gac powders due to high inlet
temperature. Additionally, it can be clearly seen that DE is a function
of value L*a*b*, therefore, increase in lightness with increased
inlet temperature was also a contribution to increasing DE. Contradictorily,
Rodríguez-Hernández et al. (2005) and Grabowski et al.
(2006) indicated that the influence of maltodextrin concentration
was found to be significant for the variation of DE in reconstituted
cactus pear juice and sweet potato puree powders, respectively.
Their different results may be due to different colour characteristics
of their raw materials and the different processing conditions.