Nanoencapsulation of flaxseed oil: Fabrication, characterization, and storage stability

Abstract

As a class of oil with high polyunsaturated fatty acid content, the poor oxidative stability of flaxseed oil (FO) has been the key factor restricting its expanded use. FO was encapsulated using flaxseed gum nano-capsules loaded with secoisolariciresinol diglucoside as wall materials. Flaxseed oil nano-capsules (FO-NC) had a particle size of 208.22 nm, an encapsulation efficiency of 96%, a PDI value of 0.131, and a zeta potential of −21.98 mV. By monitoring the changes in the above indicators during accelerated storage of FO-NC, the mechanism of the change in stability of FO-NC was comprehensively analyzed. The study also showed that the nano-encapsulated FO improved its oxidative stability by determining the fatty acid composition, peroxide value and oxidative stability index. Transmission electron (TEM) micrographs showed that FO-NCs were spherical, with a smooth surface. FTIR showed that the FO had been successfully encapsulated. The FO-NC showed good stability over 0–7 days, with higher oxidative stability than unencapsulated FO emulsions. Encapsulation efficiency is a key factor in the stability of FO-NC. The results suggest that nano-encapsulation is an effective means to enhance the oxidative stability of FO.