OMB Meeting Book_9-11-14

Table 2012.13A. Stoichiometric factors (Si FA) for converting the fatty acid methyl esters (FAME) to fatty acids (FA) Chain length Configuration and group Abbreviation FAME m.w. FA m.w. TAG m.w. Si (FA) C4:0 SFA 102.1 88.1 302.4 0.863 C6:0 SFA 130.2 116.2 386.5 0.892 C8:0 SFA 158.3 144.2 470.7 0.911 C10:0 SFA 186.3 172.3 554.9 0.925 C12:0 SFA 214.4 200.3 639.0 0.935 C14:0 SFA 242.4 228.4 723.2 0.942 C14:1 ω-5 (or n-5) cis MUFA 240.4 226.4 717.1 0.942 C15:0 SFA 256.4 242.4 765.3 0.945 C15:1 ω-5 (or n-5) cis MUFA 254.4 240.4 759.2 0.945 C16:0 SFA 270.5 256.4 807.3 0.948 C16:1 ω-7 (or n-7) cis MUFA 268.5 254.4 801.3 0.948 C17:0 SFA 284.5 270.5 849.4 0.951 C17:1 ω-7 (or n-7) cis MUFA 282.5 268.4 843.4 0.950 C18:0 SFA 298.5 284.5 891.5 0.953 C18:1 TFA trans a 296.5 282.5 885.5 0.953 C18:1 ω-9 (or n-9) cis MUFA 296.5 282.5 885.5 0.953 C18.2 TFA trans a 294.5 280.5 879.4 0.952 C18:2 ω-6 (or n-6) cis PUFA LA 294.5 280.5 879.4 0.952 C18:2 CLA ω-6 (or n-6) cis / trans PUFA CLA 294.5 280.5 879.4 0.952 C18:3 ω-6 (or n-6) cis PUFA 292.5 278.4 873.4 0.952 C18:3 TFA trans a 292.5 278.4 873.4 0.952 C18:3 ω-3 (or n-3) cis PUFA ALA 292.5 278.4 873.4 0.952 C20:0 SFA 326.6 312.5 975.7 0.957 C20:1 ω-9 (or n-9) cis MUFA 324.6 310.5 969.6 0.957 C20:2 ω-6 (or n-6) cis PUFA 322.5 308.5 963.6 0.957 C20:3 ω-6 (or n-6) cis PUFA 320.5 306.5 957.5 0.956 C20:3 ω-3 (or n-3) cis PUFA 320.5 306.5 957.5 0.956 C20:4 ω-6 (or n-6) cis PUFA ARA 318.5 304.5 951.5 0.956 C20:5 ω-3 (or n-3) cis PUFA EPA 316.5 302.5 945.4 0.956 C21:0 SFA 340.6 326.6 1017.8 0.959 C22:0 SFA 354.6 340.6 1059.9 0.960 C22:1 ω-9 (or n-9) cis MUFA 352.6 338.6 1053.8 0.960 C22:2 ω-6 (or n-6) cis PUFA 350.6 336.6 1047.8 0.960 C22:6 ω-3 (or n-3) cis PUFA DHA 342.5 328.5 1023.6 0.959 C24:0 SFA 382.7 368.7 1144.0 0.963 C24:1 ω-9 (or n-9) cis MUFA 380.7 366.6 1137.9 0.963 a Does not include trans fatty acids into MUFA and PUFA sums.

Case 3.—Presence of C18:3 TFA isomers (three isomers, C18:3 c,c,t; C18:3 c,t,c; and C18:3 t,c,c).— The same as described above for Case 2, but with the C18:3 c,t,c. The peak area of this isomer is always small and is sometime lower than the LOQ. In case of co- elution with C20:1 n-9 (or another C20:1 isomer), its contribution on total C18:3 TFA is negligible. Case 4.—Presence of C18:3 TFA isomers (four isomers, C18:3 t,c,t; C18:3 c,c,t; C18:3 c,t,c; and C18:3 t,c,c) .—The same as described above (Cases 2 and 3), but with the C18:3 t,c,t. This isomer is formed by the degradation of C18:3 c,c,t and C18:3

confirmatory tool to verify the presence of TFA isomers. Most of the time, a maximum number of four isomers is encountered. Case 1 .— Absence of C18:3 TFA isomers .—No peak (if only one peak is detected; see the comment above regarding the presence of another C20:1 isomer in milk). The presence of only one C18:3 TFA isomer is not possible. Case 2.—Presence of C18:3 TFA isomers (a minimum of two isomers, C18:3 c,c,t and C18:3 t,c,c.) .—The C18:3 t,c,c peak area is approximately 80% of the C18:3 c,c,t peak area (ratio 5:4). This ratio is always constant when other C18:3 TFA isomers are present.

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