Polyphenolic fractions improve the oxidative stability of microencapsulated linseed oil

Abstract

The main objective of this study was to evaluate the effect of incorporating polyphenolic-enriched fractions from murta leaves on the oxidative stability of linseed oil microencapsulated by spray drying. For this purpose, polyphenol-enriched fractions from murta leaves were separated by gel permeation chromatography and chemically characterized. The oxidative stability of microencapsulated linseed oil (MLO) with antioxidants was evaluated in storage conditions at 25°C for 40 days. The antioxidant effects of the polyphenolic fractions and commercial antioxidants (BHT and trolox) on microencapsulated oil were evaluated by the value of conjugated dienes, peroxide, and p-anisidine. In the initiation step of the oxidation, no significant oxidation delay (p>0.05) in MLO containing fractions F6, F8, or BHT and trolox was observed. However, in the termination step of the oxidation, the addition of fractions F6, F8, and BHT and trolox decreases significantly (p≤0.05) the rancidity in MLO. Furthermore, the results of this study demonstrated the importance of the addition of natural antioxidants such as fractions of murta leaf extract in microencapsulated linseed oil to increase its resistance to oxidation. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.