Oxidative stability omega

Gas Chromatographic Methods. Gas chromatographic methods may be used for measuring volatile oxidation products. Static headspace, dynamic headspace, or direct injection methods may be employed. Specific aldehydes may be measured as indicators for oxidative stability of oils and fats. Thus, propanal is an and as indicator for stability of omega-3 fatty acids, whereas hexanal is best for following the oxidative stability of omega-6 fatty acids. 

The combination of high oleic acid and low Unoleic add, with the conventionally low-saturated fatty acid content, is the key to the very measurable benefits of the Omega-9 oils for the food industry, that is, improved oxidative stability resulting in longer shelf life, and longer fry life, as well as clean and bland taste profile. Table 5.6 shows some physical and chemical properties of these oils. 

Omega-9 oils are considered high quality frying oils because they fulfill all of the above-mentioned charaeteristics. They are naturally low in saturated fat (7%), high in oleic acid (>72%) and low in polyunsaturated fatty acids (<18% linoleic add and <2% linolenic acid). This fatty acid profile provides high oxidative stability (17 h OSI) and a high smoke point (>450°F). 

Omega-9 oils can also blend with other liquid oils (com, conventional canola, etc.) to attain the desired qualities of the fatty acid profile, oxidative stability, taste and eost. Figure 5.2 shows the difference in the saturated and trans fats in French fries when fried in partially hydrogenated soyabean oil and Omega-9 canola oil. 

Omega-9 oils are well suited for this application because of high oxidative stability, resistance to polymerize and low-saturated fat making it possible to operate without heating the spray nozzles, as it is liquid at room temperature. 

Kodali, D.R. Oxidative stability measurement of high-stability oils by pressure differential scanning calorimeter (PDSC). J. Agric. Food Chem. 2005, 53, 7649-7653. Kris-Etherton, P.M. Harris, W.S. Appel, L.J. Fish consumption, fish oil, omega-3 fatty acids and cardiovascular disease. Circulation 2002, 106, 2747-2757. 

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