Abstract:

Liposoluble cochineal dye was prepared by esterification of carminic acid as the major component of cochineal
dye with lauroyl chloride. The preparation conditions were optimized by single factor design and validated as follows:
1.0 g of cochineal dye, 15.3 mL of dimethyl formamide (DMF), 4.5 g of lauroyl chloride, a reaction temperature of 42.0 ℃
and a reaction duration of 1 h. Under these conditions, the recovery of cochineal dye was 59.35%. The structure of the resulting
liposoluble cochineal dye was characterized by Fourier transform infrared spectroscopy (FITR) and ultraviolet-visible (UV-Vis)
spectroscopy. Results showed that esterification took place between cochineal dye and lauroyl chloride and cochineal laurate was
obtained. The product was soluble and stable in edible corn oil with a solubility of 15.06 g/100 g at 20 ℃.

Key words: cochineal dye, lauroyl chloride, liposoluble, modification, characterization