Yellowness index values
were in the range of 47–49. As discussed in the literature, yellowness
is a numerical depiction of how yellowness of a material is in comparison
with a clear water-white standard and indicates the degree of departure
of an object color from colorless or from a preferred white.
The decrease in the yellowness values attests greater clarity in terms
of cleanness or clearness (Bozkurt & Bayram, 2006).