Analysis for tomato seed oil was performed using a gas chromatography-
flame ionization detector (GC-FID). Tomato oil consists of
polyunsaturated fatty acids (PUFAs) that must be analyzed by high
temperature gas chromatography. Before injection, the extracted
oil was converted to methyl esters according to the method of
Roy et al. (1996). Two ml of hexane was added to 50 mg of extracted
oil. Then, 0.2 ml of 2 M KOH solution in methanol was
added to the sample and shaken at 100 C for 10 min. The sample
was centrifuged at 1500 rpm (309.5 G-force) for 15 min. Methyl esters
dissolved in the hexane layer were separated by a funnel and
analyzed by GC-FID (Gas Chromatography GC-14A, Shimadzu, Japan)
equipped with a DB-5 capillary column (15 m 0.250 mm
0.25 lm). The oven temperature was increased from 70 to
320 C at 5C/min intervals. The injector and detector temperatures
were controlled at 250 and 300 C, respectively. The injection
volume was 0.6 ll. All samples were injected in duplicate. The peak
area percentage of each PUFA in the extract at each extraction condition
is cited as mean ± standard deviation.