A 5971MSD quadruple-type (electron accelerating voltage 70 eV) Hewlett-Packard mass spectrometer (MS) was used. The volatiles were separated on a cross-linked methyl silicone capillary column DBl (60 m in length, 0.25 mm i.d. 1 pm thick coating), at 40°C. One ml of head-space gas was withdrawn from the conical flasks and injected into the GC-MS. The gas flow was split up in ratio of 1 : 6. The emerging volatiles from the GC were tracked by an MS in the selective ion monitoring (SIM) mode. Two ions of HzS with a mass/charge (m/z) ratio of 34 and 33, representing the molecular ion, M+ and the fragment ion M t, that had lost a hydrogen atom from M+ respectively, were selected. The mass spectra of the strawberry volatiles were compared to those of pure HIS.