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to an acceptable level by heating the syringe to 60°C just before taking the sample. The gas
chromatograph was the Hewlett-Packard 5890A fitted with 25 m capillary column, 320 µm I.D.
containing a film of BP-20 that was 1.0 µm thick. The column was maintained at an initial temperature
of 35°C for 5 min. and then programmed up to 200°C at 10°/min. A 500 ml sample of head space was
introduced into the column through a split injection system with a split ratio of 3:1. The Hewlett-
Packard 5995C mass spectrometer was employed with the chromatograph. The transfer line was
maintained at 250°C, the source at 240°C and the separator at the same temperature 240°C. A
chromatogram of the volatile materials contained in the head space over some oranges that had been
incised with ten shallow cuts 20 cm long, is shown in figure 5.31.

Figure 5.31
Chromatogram of the Volatiles Contained in the Head
Space Over a Mechanically Damaged Orange (ref.41)
It is seen that an satisfactory chromatographic resolution is achieved and the solutes could be easily
identified by spectra matching. The authors