caa a22 4500 465797482 CHVBK 20180323112042.0 cr unu---uuuuu 170327e19901101xx s 000 0 eng 10.1007/BF02540496 doi (NATIONALLICENCE)springer-10.1007/BF02540496 Determination of cis and trans -Octadecenoic acids in margarines by gas liquid chromatography-infrared spectrophotometry [Elektronische Daten] [W. Ratnayake, R. Hollywood, E. O'Grady, J. Beare-Rogers] A combined capillary gas liquid chromatography (GLC) and infrared spectrophotometry (IR) method is described for the determination ofcis andtrans-octadecenoic acids in margarines made from partially hydrogenated vegetable oils. The totaltrans-unsaturation of margarine fatty acid methyl esters determined by IR, with methyl elaidate as the external standard, was correlated to the capillary GLC weight percentages of the componenttrans fatty acid methyl esters by the mathematical formula: IRtrans=%18∶1t+0.84×%18.2t+1.74×%18∶2tt+ 0.84×%18∶3t where 0.84, 1.74 and 0.84 are the correction factors which relate the GLC weight percentages to the IRtrans-equivalents for mono-trans-octadecadienoic (18∶2t),trans, trans-octadecadienoic (18∶2tt) and mono-trans-octadecatrienoic (18∶3t) acids, respectively. This formula forms the basis for the determination of totaltrans-andcis-octadecenoic acids in partially hydrogenated vegetable oils. From the weight percentages of 18∶2t, 18∶2tt and 18∶3t determined by capillary GLC on a cyanosilicone liquid phase and the totaltrans-unsaturation by IR, the percentage of the totaltrans-octadecenoic acids (18∶1t) is calculated using the formula. The difference between the total octadecenoic acids (18∶1), determined by capillary GLC, and the 18∶1t gives the totalcis-octadecenoic acids. AOCS Press, 1990 cis and trans -Octadecenoates nationallicence cis-trans fatty acid isomers nationallicence GLC-IR analysis nationallicence hydrogenated fat nationallicence margarine nationallicence Ratnayake W. Food Directorate, Health Protection Branch, Health and Welfare Canada, Bureau of Nutritional Sciences, K1A 0L2, Ottawa, Ontario, Canada aut Hollywood R. Food Directorate, Health Protection Branch, Health and Welfare Canada, Bureau of Nutritional Sciences, K1A 0L2, Ottawa, Ontario, Canada aut O'Grady E. Food Directorate, Health Protection Branch, Health and Welfare Canada, Bureau of Nutritional Sciences, K1A 0L2, Ottawa, Ontario, Canada aut Beare-Rogers J. Food Directorate, Health Protection Branch, Health and Welfare Canada, Bureau of Nutritional Sciences, K1A 0L2, Ottawa, Ontario, Canada aut Journal of the American Oil Chemists' Society Springer-Verlag 67/11(1990-11-01), 804-810 0003-021X 67:11<804 1990 67 11746 https://doi.org/10.1007/BF02540496 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF02540496 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Ratnayake W. Food Directorate, Health Protection Branch, Health and Welfare Canada, Bureau of Nutritional Sciences, K1A 0L2, Ottawa, Ontario, Canada aut NATIONALLICENCE 700 1- Hollywood R. Food Directorate, Health Protection Branch, Health and Welfare Canada, Bureau of Nutritional Sciences, K1A 0L2, Ottawa, Ontario, Canada aut NATIONALLICENCE 700 1- O'Grady E. Food Directorate, Health Protection Branch, Health and Welfare Canada, Bureau of Nutritional Sciences, K1A 0L2, Ottawa, Ontario, Canada aut NATIONALLICENCE 700 1- Beare-Rogers J. Food Directorate, Health Protection Branch, Health and Welfare Canada, Bureau of Nutritional Sciences, K1A 0L2, Ottawa, Ontario, Canada aut NATIONALLICENCE 773 0- Journal of the American Oil Chemists' Society Springer-Verlag 67/11(1990-11-01), 804-810 0003-021X 67:11<804 1990 67 11746 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer