Microencapsulation of an omega-3 oil in a Trehalose Matrix

MARIA SOLEDAD ALVAREZ CERIMEDO; ROBERTO JORGE CANDAL; MARIA L HERRERA

Long Beach, California

Congreso; 103rd AOCS Annual Meeting & Expo; 2012

American Oil Chemists' Society

Microencapsulation of an ω-3 oil in a Trehalose Matrix. M.S. Álvarez-Cerimedo1,2, R.J. Candal3,2, and M.L. Herrera*1,2, 1University of Buenos Aires, Faculty of Exact and Natural Sciences, Buenos Aires, CABA, Argentina, 2National Research Council of Argentina (CONICET), Buenos Aires, CABA, Argentina, 3National University of San Martin, School of Science and Technology, San Martin, Buenos Aires, Argentina. It is well known that stability of lipids is improved by encapsulation since it is a physical means offering protection against oxidation without the need of antioxidants. A concentrated from fish oil, mainly from salmon, rich in DHA (C22:6), EPA (C20:5), and DPA (C22:5) was encapsulated by freeze-drying emulsions. The selected emulsifier was sodium caseinate at 0.5, 2, and 5 wt% levels. The matrix was trehalose, a known cryoprotectant, which was used at 20 or 30 wt% level. The ability to retain the core material with time was studied by measuring the extractable and non extractable fat of the different formulations. Efficiency of encapsulation was strongly dependent on formulation. The 20 wt% trehalose, 5 wt% sodium caseinate powder had a retention efficiency of 80%. This powder has a water content of 5%. Its matrix was in the amorphous state. The mean volume diameter of particles (D4,3) was smaller than those of the other formulations. Besides, D4,3 of the reconstituted emulsion showed no significant differences compared to the original emulsion D4,3, showing that freeze-thaw did not affect initial droplet size distribution. This emulsion was stable at least for 1 week and its structure showed individual droplets evenly distributed.