After UV-C exposure and thermal pasteurization, an increasein lightness (L*), and decrease in redness (+a*) and yellow-ness (+b*) were observed in juice samples. The increase in L*value makes the juice brighter and more transparent due toimpairment of coloured compound initially present in juice.Natural pigments such as carotenoids largely contribute tothe yellow colour (+b*value) of Chokanan mango juice andheat causes accelerated carotenoid isomerization (Rodríguez-Amaya, 1997) which leads to loss of yellowness in juice(decreased +b*value).