engleski

The effect of the addition of laurel extract and plant material on fish oil oxidative stability

Fish oils that contain high levels of polyunsaturated fatty acids have a very important role in the human diet. However, due to their specific chemical composition, they are more susceptive to lipid oxidation than other fats and oils. Lipid oxidation is a complex process that causes rancidity, off-flavours, and losses of nutritional value and functional properties of foods. At ambient conditions it occurs slowly, so several accelerated methods (employing high temperatures and air-flow supply) have been developed to estimate the oxidative stability and shelf life of oil-containing products in a relatively short time. Tocopherols are usually used to stabilize fish oil ; however, their activity is not always effective, especially in the presence of high concentrations of metals. The aim of this study was to explore the effect of the addition of laurel (plant material and extract) on the stability of fish oil, using a Rancimat apparatus. According to the obtained results, the addition of laurel plant material caused prolonged oil stability and the effect was influenced by the size of the plant material particles and by the added amount of plant material. The same effect was obtained by extract addition (50 and 100 µL), while a higher concentration of phenolics caused the opposite effect and accelerated fish oil oxidation.

Laurus nobilis, Rancimat method, oxidation, antioxidants, phenolics

This work has been partially supported by the Croatian Science Foundation under the project IP-2014-09-6897 and by the project of the Student Union of the the University of Split “Najbolje od Dalmacije - znanost potvrđuje tradiciju”.