Physical Chemical Stability of Emulsions Formulated with Marine Oil

ALVAREZ CERIMEDO MS; HERRERA ML; CANDAL RJ

Orlando, Florida, USA

Congreso; 100th American Oil Chemists' Society Annual Meeting and Expo; 2009

American Oil Chemists' Society

The development of an effective strategy to prevent undesirable changes in the properties of a particular food emulsion depends on the dominant physicochemical mechanism. It is therefore important for food scientists to identify the relative importance of each mechanism. The n-3 fatty acids, such as alpha-linoleic acid (ALA, 18:3 n-3), eicosapentaenoic acid (EPA, 20:5 n-3) and docosahexaenoic acid (DHA, 22:6 n-3) have many health benefits. Oil enriched in these fatty acids is of great importance for supplement makers and functional food formulators. Stability of emulsions formulated with commercial fish oil, trehalose, and sodium caseinate (NaCas) as emulsifier was studied using a TMA 2000 analyzer. The reading head is composed of a pulsed near-IR light source (lambda= 850 nm) and two synchronous detectors. The samples were put in a cylindrical glass measurement cell and the backscattering (BS) and transmission (T) profiles as a function of the sample height (total height = 70 mm) were studied in quiescent conditions at 22.5°C. Five concentrations of NaCas were used: 1, 2, 3, 4 and 5 wt%. Droplet size diminished as sodium caseinate concentration increased. For 1 wt% NaCas concentration migration was the most important mechanism of destabilization. As the concentration increased coalescence occurred and became the main mechanism.