The present invention relates to a process for the isolation of carotenoid crystals having lutein and zeaxanthin in a weight ratio of 10:1, 5:1 and 1:1, respectively. The process comprises contacting a plant source rich in lutein with hexane and extracting at a temperature of 40°C to 60°C to obtain an oleoresin rich in lutein; contacting a plant source rich in zeaxanthin with hexane and extracting at a temperature of 40°C to 60°C to obtain an oleoresin rich in zeaxanthin. The oleoresin rich in lutein and the oleoresin rich in zeaxanthin are mixed separately in a ratios ranging from 80:20(w/w) to 90:10(w/w) or 70:30(w/w) to 30:70(w/w) or 10:90(w/w) to 20:80(w/w), respectively, and homogenized to obtain a mixed oleoresin. The mixed oleoresin is hydrolyzed with an alcoholic alkali at a temperature of 70°C to 80°C to obtain a reaction mixture. The carotenoid crystals are precipitated by adding hot water to the reaction mixture to form a precipitate. Carotenoid crystals having lutein and zeaxanthin in a weight ratio of 10:1 or 5:1 or 1:1, respectively, are obtained by filtering, washing, and drying the precipitate.