Supercritical Anti Solvent Coprecipitation of β-carotene and PEG: Influence of Process Parameters

FACUNDO MATTEA; ÁNGEL MARTÍN; MARÍA JOSÉ COCERO

Kyoto

Congreso; 8th International Symposium on Supercritical Fluids; 2006

Carotenoids are natural compounds widely employed in industrial and pharmaceutical processes due to their characteristics as natural colorants and antioxidants. Most of these processes use a mix of the carotenoids with bio-polymers to improve their stability, dissolution rate in water, and makes easier the dosage and handling of the product. The Supercritical Anti Solvent (SAS) process is especially suitable for the production of fine powders of these mixtures, as it yields solvent-free products with a reduced thermal degradation or oxidation of the carotenoids. In a previous work the Supercritical Anti Solvent (SAS) micronization process was studied to co-precipitate β-carotene with polyethylene glycol (PEG) [1] and lutein with poly-lactic acid (PLA) [2]. The viability of the process was confirmed and the optimal pressure and temperature conditions were established (10 MPa and 288 oK). It was also found that the concentration ratio between the polymer and carotenoid had a great influence over the coating results, but a complete study of this influence was not made. In this work the concentration ratio: PEG concentration (CPEG) / Carotenoid concentration (CCAR) was varied from 4:1 to 1:4, and two different injector diameters were tested. The resulting products were characterized with x-ray diffraction (XRD), differential scanning calorimetry (DSC), and scanning electron microscopy (SEM) in order to analyze the influence of these parameters on particle morphology, and to determine the best operating conditions to acquire complete polymer covered carotenoid microparticles