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by Rebecca Wittrig, Ph.D., Food, Flavor, & Fragrance Innovations Chemist
Analyzing Fatty Acid Methyl Esters
(FAMEs) by GC
Using Restek Capillary Columns and
Analytical Reference Materials
✔ Resolve individual cisand trans isomers on our new 100-meter Rt-2560 column.
✔ Separate saturated/unsaturated FAMEs on a FAMEWAX™ column.
✔ New Food Industry FAME Mix includes methyl esters of 37 common fatty acids in
animal, vegetable, and marine oils.
✔ Use new qualitative cis/transFAME Mix to identify C18:1 isomers.
Fatty acid methyl ester (FAME) analyses are an
important tool for characterizing fats and oils and for
determining the total fat content in foods. A new cap-
illary GC column and three new reference mixtures
from Restek can help you obtain the best results for
these challenging assays.
Individual cis and trans isomers of unsaturated
FAMEs, such as octadecenoic acid (C18:1) or
octadecadienoic acid (C18:2), are resolved on an
Rt-2560 column—our new 100-meter
biscyanopropyl phase column. An analysis of C18:1
cis and trans isomers is shown on page 9 of this
Advantage. The ability to resolve these isomers makes
an Rt-2560 column the column of choice for analyz-
ing partially hydrogenated fats and oils; the column
meets the requirements of AOAC Method 996.06.
Figure 1 shows a separation of 37 FAMEs commonly
encountered by food quality chemists, obtained by
using an Rt-2560 column.
GC_FF00649
Column: Rt-2560, 100m, 0.25mm ID, 0.2µm
(cat.# 13199)
Sample: 30mg/mL total FAMEs in methylene chloride
Inj.: 2.0µL split (split ratio 200:1), 4mm inlet
liner (cat.# 20814)
Inj. temp.: 225°C
Carrier gas: hydrogen, constant flow
Flow rate: 1.2mL/min.
Oven temp.: 100°C (4 min. hold)
to 240°C @ 3°C/min. (10 min. hold)
Det.: FID @ 250°C
Compound % in Mix
1. C4:0 methyl butyrate 4.0
2. C6:0 methyl hexanoate 4.0
3. C8:0 methyl octanoate 4.0
4. C10:0 methyl decanoate 4.0
5. C11:0 methyl undecanoate 2.0
6. C12:0 methyl laurate 4.0
7. C13:0 methyl tridecanoate 2.0
8. C14:0 methyl myristate 4.0
9. C14:1 methyl myristoleate ( cis-9) 2.0
10. C15:0 methyl pentadecanoate 2.0
11. C15:1 methyl pentadecenoate ( cis-10) 2.0
12. C16:0 methyl palmitate 6.0
13. C16:1 methyl palmitoleate ( cis-9) 2.0
14. C17:0 methyl heptadecanoate 2.0
15. C17:1 methyl heptadecenoate ( cis-10) 2.0
16. C18:0 methyl stearate 4.0
17. C18:1 methyl elaidate ( trans-9) 2.0
18. C18:1 methyl oleate ( cis-9) 4.0
19. C18:2 methyl linoleaidate ( trans-9,12) 2.0
20. C18:2 methyl linoleate ( cis-9,12) 2.0
21. C18:3 methyl γ-linolenate ( cis-6,9,12) 2.0
22. C20:0 methyl arachidate 4.0
23. C20:1 methyl eicosenoate ( cis-11) 2.0
24. C18:3 methyl linolenate ( cis-9,12,15) 2.0
25. C21:0 methyl heneicosanoate 2.0
26. C20:2 methyl eicosadienoate ( cis-11,14) 2.0
27. C20:3 methyl eicosatrienoate (cis-11,14,17) 2.0
28. C22:0 methyl behenate 4.0
29. C22:1 methyl erucate ( cis-13) 2.0
30. C20:3 methyl eicosatrienoate (cis-11,14,17) 2.0
31. C20:4 methyl arachidonate ( cis-5,8,11,14) 2.0
32. C23:0 methyl tricosanoate 2.0
33. C22:2 methyl docosadienoate ( cis-13,16) 2.0
34. C20:5 methyl eicosapentaenoate 2.0
(cis-5,8,11,14,17)
35. C24:0 methyl lignocerate 4.0
36. C24:1 methyl nervonate ( cis-15) 2.0
37. C22:6 methyl docosahexaenoate 2.0
(cis-4,7,10,13,16,19)
For analyzing mixtures of saturated and unsaturated
fatty acid methyl esters, stationary phases consisting
of polyethylene glycol (e.g., Carbowax®) typically are
used. FAMEWAX™ columns offer excellent selectivity
for analyses of polyunsaturated fatty acids. The poly-
ethylene glycol stationary phase is especially capable
of resolving Omega-3 polyunsaturated FAMEs, such as
eicosapentenoic acid (C20:5) and docosahexenoic
acid (C22:6). FAMEWAX™ columns combine excellent
resolution of polyunsaturated FAMEs with significantly
reduced analysis times, compared to traditional
Carbowax® stationary phases.
In addition to our new Rt-2560 capillary column
for cis and trans isomers analysis, we are introduc-
ing three new FAMEs mixtures to support food and
nutraceuticals testing. Our 37-component Food
Industry FAME Mix is a complete profile of the
common fatty acids in animal, vegetable, and
marine oils, including many polyunsaturated
FAMEs, such as C20:5 and C22:6. Figure 1 is a
chromatographic separation of this mix. New NLEA
FAME Mix was designed with AOAC Method 996.06
in mind; it can be used as the calibration standard
for this Fat by Fatty Acid Composition method. Use
our qualitative cis/trans FAME Mix to identify the
cis and trans isomers of octadecenoic acid
(C18:1). For descriptions and ordering information
for the latter two mixes, and an analysis of the
cis/trans FAME Mix, see page 9.
Before you attempt to characterize a fat or oil, contact
Restek for capillary columns and reference materials
that can help you obtain the data you need.
Figure 1
37-Component Food Industry FAME Mix includes common components of animal, vegetable,
and marine oils.
Ordering Information | Rt-2560 Column (Fused Silica)
Component
C4:0
C6:0
C8:0
C10:0
C11:0
C12:0
C13:0
C14:0
C14:1( cis-9)
C15:0
C15:1( cis-10)
C16:0
C16;1( cis-9)
C17:0
C17:1( cis-10)
C18:0
C18:1( trans-9)
C18:1( cis-9)
C18:2(all- trans-9.12)
Component
C18:2(all- cis-9,12)
C18:3(all- cis6,9,12)
C18:3(all- cis9,12,15)
C20:0
C20:1( cis-11)
C20:2(all- cis11,14)
C20:3 (all- cis 8,11,14)
C20:3(all- cis11,14,17)
C20:4(all- cis5,8,11,14)
C20:5 (all- cis 5,8,11,14,17)
C21:0
C22:0
C22:1( cis13)
C22:2(all- cis13,16)
C22:6 (all- cis 4,7,10,13,16,19)
C23:0
C24:0
C24:1( cis-15)
In methylene chloride, 1mL/ampul. For concentrations, see
Figure 1.
Food Industry FAME Mix (37 components)
ea.
35077
Descriptions and ordering
information for our NLEA
and cis/transFAMEs mixes
are on page 9 of this
Advantage.
Ordering Information | FAMEWAX™ Columns (Fused Silica)
ID df (µm) temp. limits 30-Meter
0.25mm 0.25 20 to 250°C 12497
0.32mm 0.25 20 to 250°C 12498
0.53mm 0.50 20 to 250°C 12499
ID df (µm) temp. limits 100-Meter
0.25mm 0.20 20 to 250°C 13199