DETERMINATION OF ANNATTO IN HIGH-FAT DAIRY-PRODUCTS, MARGARINE AND HARD CANDY BY SOLVENT-EXTRACTION FOLLOWED BY HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHY

Utilizing solvents such as ethanolic aqueous ammonia, petroleum ether, hexane and chloroform, annatto components alpha- and beta-norbixin and alpha- and beta-bixin were extracted from cheese, butter, margarine and hard candy. After transferring the extract into a solution of aqueous acetic acid in methanol, bixin and norbixin were determined quantitatively using high-performance liquid chromatography (HPLC) and an absorbance detector set at 500 nm. Recovery of norbixin from spiked cheese samples averaged 92.6% over a range of 1 to 110 mu g/g. Commercial cheese samples were found to contain 1.1-68.8 mu g/g total norbixin, and two samples also contained 5.1-5.6 mu g/g total bixin. Samples of uncoloured butter were spiked with bixin and recovery averaged 93.2% over a range of 0.1 to 445 mu g/g. Levels of 0.2 mu g/g total bixin and 0.91 mu g/g total norbixin were found in one commercial butter sample; the others contained trace levels of both compounds. Hard candies were prepared in the laboratory and recovery studies conducted. Recovery of norbixin averaged 88%.