Characterization of chia microencapsulated oil from freeze-dried layer-by-layer emulsions with sunflower lecithin

IXTAINA, VANESA Y.; NOLASCO, SUSANA M.; JULIO, LUCIANA M.; TOMÁS, MABEL C.

Orlando, Florida

Congreso; 2017 AOCS Annual Meeting & Industry Showcases; 2017

American Oil Chemists' Society

Microencapsulation is an alternative to protect chia oil from the adverse conditions of chemical environment, since its susceptibility to oxidation due to their high content of PUFAs. The aim of this work was to obtain and characterize chia oil microcapsules from freeze-dried layer-by-layer emulsions (LBLE). A lecithin (Lec) (-35mV at pH 3) and Lec+chitosan (LCh) (+45mV at pH 3) stabilized emulsions with maltodextrin addition were prepared by homogenizing (600 bar, 4 cicles) 5% wt chia oil with 95% wt aqueous solution and subsequently freeze-dried. The powders were stored in closed chambers at HR 33%, 25±2ºC and characterized in relation to moisture content, water activity, particle size, microstructure and oxidative stability. The D [3,2] mean diameter ranged from 1.2 to 2.7µm and the encapsulation efficiency was ~80% in all cases. Water activity and moisture content of powders were around 0.4 and 1.7%, respectively. Microcapsules presented porous, irregular and glass like surfaces. Both powders exhibited higher oxidative stability than no encapsulated chia oil giving LCh microcapsules the better protection against lipid oxidation. These data suggest that multilayer microcapsules could be an effective technology to deliver chia oil into functional foods.