Microemulsions (ME) are a well-known and studied field, having applications in a large range of industrial technologies.
The ability to mix oil and water to a stable mixture and to solubilize different types of active ingredients for different purposes has made this field a matter of interest for many researches.
Lycopene is a lipophilic natural pigment that has great importance to the food industry. It is used as a food coloring agent due to its non-toxicity feature. It is light sensitive to oxidative degradation by visible light radiation which limits its shelf life.
In this study we investigated the stability of two different types of lycopene: molecular lycopene and oleoresin lycopene, both solubilized in ME and dissolved in organic solvent (acetone) as control. Concentration of lycopene was measured during 4 weeks in order to determine the percent of lycopene remained after its exposure to daylight.
The results show that oleoresin lycopene maintains its concentration throughout the whole period, in both systems (ME and in solvent). On the contrary, molecular lycopene decreases up to about 50% of its initial concentration during the first week, also in both systems.
These results indicate the important role of oleoresin in the Lycopene preserving mechanism and the possibility that ME does not affect its stability.
Prof. Nissim Garti garti@vms.huji.ac.il
