Efficacy of different oils used for the extraction of annatto colour from the seeds of Bixa orellana L.

Abstract

Annatto, a naturally obtained colour is a potential and valuable Non Wood Forest Product (NWFP). It is obtained from the seeds of plant species Bixa orellana L. The present experiment was carried out to find the efficacy of different oils used for annatto colour extraction. Experiment was started with the pretreatment of seeds of B. orellana with soaking in water at 0%, 50%, 100% and 150% (v/w) for 24 hrs at room temperature and colour extraction with castor oil at 100°C showed that maximum bixin (%) was found from the pretreated seeds with 50% (v/w) water soaking i.e., 0.46% bixin. Similarly for oil soluble annatto extraction method, the maximum extraction of bixin (0.99 %) was found with castor oil at 120°C for 1 hr and least bixin (0.03 %) was recorded with mustard oil at 60oC temperature for 1 hr. Sesame oil and ground nut oil were also showed better extractability. Out of different treatments, castor oil at 120°C for 1 hr gave better result with respect to bixin extraction as compared to others.