Natural pigments and antioxidants properties of annatto extract at various pH of distilled water solvent and extraction times

Abstract

Annatto is a natural colouring agent obtained from the outer coats of the seeds of the Bixa orellana. Carotenoid pigment in annatto consists of bixin and norbixin. Pigment extraction from annatto seeds is commonly done by indirect extraction using organic solvents and direct extraction using oil or aqueous alkali. This research aims to characterize the natural pigment and antioxidants of annatto extract. The annatto was extracted by maceration using distilled water at various pH and extraction times. The distilled water pH variations used in this study were 4, 7, and 9 while the extraction times were 5, 7.5 and 10 mins. Analyzing bixin and norbixin revealed the potential of annatto extract as a natural pigment, while phenol and flavonoids disclose the potential as a natural antioxidant. The results showed that varying pH of distilled water and time of extraction influences the bixin, norbixin, total phenol, and flavonoid contents of annatto extract. Annatto extraction using distilled water produces higher levels of bixin than norbixin. The highest levels of bixin (61.06%) were built in distilled water pH 7 for 7.5 mins of extraction, while the highest levels of norbixin (30%) were produced in distilled water pH 7 for 10 mins. Extraction using pH 4 creates a higher level of total phenol while increasing the extraction time up to 10 mins decreased the total phenol content. However, high levels of flavonoids were made in extraction using alkaline pH distilled water (pH 9) for 10 mins. The results showed that all extracts have the potential as natural pigments and antioxidants.