In vitro study of bioaccesibility and oxidative stability of squalene in microencapsulated oil

Abstract

However, squalence is a polyunsaturated hydrocarbon highly susceptible to oxidation and may be affected by the prooxidant conditions of the digestion process. The objective of this work was to examine the effect of simulated gastronintestinal conditions on squalene stability in sunflower oil microencapsulated with casinate-lactose (CL) or modified starch (MS) by spray-drying. Squalene and its saturated analogue, squalane, were added to the oil (10,000 mg/kg oil) before microencapsulation. Encapsulation efficiencies obtained were 94.7 and 99.2% for CL and MS, respectively. For in vitro assays, simulated gastric and intestinal fluids were used, and released oil was extracted with organic solvents following gastric and intestinal digestions. results showed that bioaccesibility of squalene was similar for CL and MS (about 70%) but oil was mostly released under gastric conditions for CL whereas this ocurred under intestinal conditions fro MS. While only 39% of squalene in nonencapsulated oil remained intact after the whole digestion process, 54 and 67% of total squalence was bioaccesible and unaltered in CL and MS, respectively. In both CL and MS, the greatest oxidation degree of the squalene released occurred in the gastric medium. No significant oxidation was detected on the squalene not released from microcapsules throughout the complete digestion process. In conclusion, microencapsulation increased oxidative stability of squalene, especially in the case of MS due to ots lower release rate under gastric conditions.