Characterization of Flaxseed Oil for Nuclear Magnetic Resonance and Its Encapsulation

Abstract

Flaxseed (Linum usitatissimum L.) is one of the oldest crops known by humans and it has been used in numerous applications, such as in the textile industry, feed formulation, fertilizers, and paper industry. However, nowadays these seeds have won an important highlight for human consumption due to their active ingredients that make them an excellent functional food. Thus, this study aimed to extract flaxseed oil, an oil rich in omega 3 and 6, characterize it by using nuclear magnetic resonance (NMR) and Fourier-transform infrared spectroscopy (FTIR) and then encapsulate this oil in polycaprolactone (PCL) on the micro scale, using the nanoprecipitation technique and subsequently freeze-drying. To determine the mean diameter, the dynamic light scattering technique (DLS) was used, and to verify whether there was encapsulation, the pulse sequence MSE-FID, an NMR sequence in the time domain, was also used. In addition to the previously mentioned techniques, X-ray diffraction (XRD) was also employed. Flaxseed flour was also analyzed by time-domain NMR and FTIR. The results obtained by NMR show that the oil consists of fatty acid esters in the form of triglycerides in which there is the presence of esters of α-linolenic and linoleic acids, respectively ALA and LA, according to the literature. Regarding the material after encapsulation, it presented a mean diameter of 445.2 ± 41 nm and PDI of 0.674 ± 0.064, therefore classified as microparticles. Finally, using the sequence MSE-FID and the FTIR, it can be concluded that there has been the microencapsulation of flaxseed oil in the particles formed.