The FA composition in fresh palm oil and non-fried chicken
fillets was shown in Supplementary Tables 1 and 2. The major fatty
acids in fresh palm oil were oleic acid, palmitic acid and linoleic
acid, whereas oleic acid and linoleic acid were the major components
in non-fried chicken fillets. The main TFA isomers found in
fresh palm oil before the start of frying were 9c 12t C18:2, 9t 12c
C18:2 isomers, among which 9c 12t C18:2 constituted the largest
portion (0.92 0.07 mg/g), followed by 9t 12c C18:2
(0.79 0.07 mg/g) (Supplementary Table 1). Interestingly, 9t C18:1
was not detected. These results were quite different from the fatty
acid profile of other vegetable oils such as soybean oil, rapeseed oil,
sunflower oil and corn oil, which were reported to be rich in 9t
C18:1 with a high level of 0.03e0.08 g/100 g (Hou et al., 2012). The
initial amounts of total trans fatty acids in our oil samples were
1.71 mg/g (0.18%) (Supplementary Table 1).