Technical feasibility research is being performed on the use of supercritical fluid to separate naturally occurring coloring and flavoring pigments from their botanical sources. Supercritical fluid technology is an innovation that substitutes compressed gases, at pressures and temperatures above their thermodynamic critical points, for liquid phase solvents. In this physical state, compressed gases have the solvating power of common liquid solvents, but retain the mass transfer and diffusion properties of a gas. Supercritical fluids are superior solvents for analyzing and purifying a wide range of organic and biological products.Currently used synthetic food colorants, such as FD&C Red No. 40, are suspected carcinogens. Natural red colorants are a potential alternative; however, current technology for the isolation of these colorants involves extraction with harmful organic solvents such as hexane, methanol, methylene chloride, and acetone. The application of supercritical fluid extraction for this purpose could provide an alternative supply of pure, solvent-free, noncarcinogenic natural coloring and flavoring compounds for food products.Anthocyanin-containing botanicals will be tested to determine the extractability of their pigment components with supercritical carbon dioxide. The effect of a number of experimental parameters on extraction rate will be studied and extracted pigments will be tested for color value and composition.National Institute Of General Medical Sciences
