5,6-epoxidecarotenoids (cis-violaxanthin and antheraxanthin) often serves as the predominant carotenoids in fresh orange juice or juice without heat treatment, isomerizations of the main 5,6-epoxide carotenoids to 5,8-epoxides was probably responsible for the color changes of HTST-processed (90 °C, 30 s) juice (Lee & Coates, 2003).