Co-precipitation of carotenoids and bio polymers with a supercritical antisolvent process

ÁNGEL MARTÍN; FACUNDO MATTEA; FERNANDO MIGUEL; MARÍA JOSÉ COCERO

Erlangen

Congreso; 3rd International Meeting On High Pressure Chemical Engineering; 2006

University of Erlangen

The Supercritical Anti Solvent (SAS) micronization process allows the production of solvent- free microparticles with a reduced thermal degradation or oxidation of the product. Due to these characteristics, this technology is very suitable for the processing of pharmaceuticals or food additives. In previous works, this process has been successfully applied to precipitate different carotenoids (β-carotene, lycopene and lutein), using dichloromethane as the organic solvent and SC-CO2 as antisolvent. In some industrial formulations, these carotenoids are mixed with bio-polymers. This improves the stability of the carotenoid, its dissolution rate in water, and makes easier the dosage and handling of the product. The aim of this work is the development of a semicontinuous SAS process for the production of a mixture of carotenoids and Poly Ethylene Glycol (PEG) by co-precipitation. With this objective, the micronization of PEG with the SAS process has been studied. The experimental results have been interpreted with the aid of a phase equilibrium model based on the Perturbed-Hard-Sphere-Chain EoS. This model predicts the apparition of a liquid-liquid immiscibility region at moderate temperatures due to the co-solvent effect of CO2 on PEG, which makes difficult the precipitation in this range. The existence of this phase behavior has been corroborated by performing batch Gas Anti Solvent (GAS) precipitation experiments in a windowed vessel. Next, the co-precipitation of β-carotene and lutein with PEG with the SAS process has been carried out.