Division 5.4 Gas chromatographyF1

Operating conditions:

• Injector temperature (on-column injector) lower than solvent boiling point (68 °C);

• Detector temperature: 350 °C;

• Column temperature: programming of furnace temperature: 60 °C for 1 minute, increasing by 15 °C per minute up to 180 °C, then by 5 °C per minute up to 340 °C, then 340 °C for 13 minutes;

• Carrier gas: hydrogen or helium, set at a linear velocity sufficient to obtain the resolution reflected in Figure 1. The retention time of the C ₅₄ triglyceride must be 40 ± 5 minutes (see Figure 2). (The operating conditions indicated above are indicative. Operators will have to optimise them to obtain the desired resolution. The peak corresponding to 2-glyceryl monopalmitate must have a minimum height equal to 10 % of the recorder scale.)

• Quantity of substance injected: 0,5-1 μl of the n-hexane solution (5 ml) (5.3.3).