Table 3.
Chemical analysis of cold pressed sesame oil.
| Parameter | Method of Analysis | Oil |
|---|---|---|
| Fatty acids profile (relative%) | ||
| C16:0 | GC-FID | 9.74 ± 0.06 |
| C16:1 | GC-FID | 0.10 ± 0.03 |
| C18:0 | GC-FID | 5.41 ± 0.09 |
| C18:1n9c | GC-FID | 42.66 ± 0.35 |
| C18:2n6c | GC-FID | 41.25 ± 0.22 |
| C18:3n3 | GC-FID | 0.20 ± 0.03 |
| C20:0 | GC-FID | 0.54 ± 0.04 |
| C20:1n9 | GC-FID | 0.11 ± 0.02 |
| ∑ SFA | GC-FID | 15.68 |
| ∑ MUFA | GC-FID | 42.87 |
| ∑ PUFA | GC-FID | 41.45 |
| 18:2n6/18:3n3 | GC-FID | 203.94 |
| 18:1n9/18:2n6 | GC-FID | 1.03 |
| Total vitamin E (mg/kg) | HPLC-DAD-FLD | 483.95 ± 7.11 |
| α-Tocopherol (mg/kg) | HPLC-DAD-FLD | 13.78 ± 0.85 |
| α-Tocotrienol (mg/kg) | HPLC-DAD-FLD | 14.04 ± 0.29 |
| γ-Tocopherol (mg/kg) | HPLC-DAD-FLD | 456.13 ± 6.05 |
| Phytochemicals | ||
| TPC (mg GAE/100 g) | Spectrophotometric (765 nm) | 13.4 ± 1.3 |
| TFC (mg ECE/100 g) | Spectrophotometric (510 nm) | 20.3 ± 1.7 |
| Antioxidant activity | ||
| FRAP (μmol FSE/100 g) | Spectrophotometric (595 nm) | 215.5 ± 6.7 |
| DPPH• (mg TE/100 g) | Spectrophotometric (Kinetics reaction, 525 nm) | 7.9 ± 0.9 |
| Oxidative stability | ||
| Induction time (h) | Rancimat method | 5.8 ± 0.0 |
| Colour | ||
| Chromatic coordinates (x, y) | Spectrophotometric (445, 495, 560, 595, 625 nm) | (0.3641, 0.3647) |
| Transparency (%) | Spectrophotometric (445, 495, 560, 595, 625 nm) | 73.2 |
| Dominant wavelength (nm) | Spectrophotometric (445, 495, 560, 595, 625 nm) | 579.3 |
| Purity | Spectrophotometric (445, 495, 560, 595, 625 nm) | 27.4 |
| Peroxide value (meqO2/kg) | Titration | 2.6 ± 0.3 |
| K232 nm | Spectrophotometric (232 nm) | 0.03 |
| K270 nm | Spectrophotometric (270 nm) | 0.01 |
Values presented as mean ± standard deviation (n = 3), except for colour and oxidation products parameters (n = 1). Results of fatty acids in relative percentage (%). C16:0, palmitic; C16:1, palmitoleic; C18:0, stearic; C18:1n9c, oleic; C18:2n6c, linoleic; C18:3n3, linolenic; C20:0, arachidic; C20:1n9, eicosenoic acids; SFA, saturated; MUFA, monounsaturated; PUFA, polyunsaturated fatty acids; TPC, total phenolic compounds; GAE, gallic acid equivalents; TFC, total flavonoids content; ECE, epicatechin equivalents; FRAP, ferric reduction antioxidant power; FSE, ferrous sulphate equivalents; DPPH•, 2,2-diphenyl-1-picrylhydrazyl radical; TE, trolox equivalents; K, extinction coefficient; GC-FID, gas chromatography-flame ionization detector; HPLC-DAD-FLD, high-performance liquid chromatography-diode array detector-fluorescence light detector; ND, not detected.