The essential oil composition of two different styrax gums, Asian and American were analysed by GC and GC-MS. Fifty-eight components representing more than 99.4% of the oil from Asian styrax gum and 57 components representing more than 99% of the oil from American styrax gum were identified. The major components were styrene (70.4 and 30.9% respectively), α-pinene (19.4 and 19.6%) and β β β β β-caryophyllene (0.2 and 20.2%) for the two oils. These results show that we could identify an Asian from an American styrax by relative amounts of styrene and β β β β β-caryophyllene in the essential oils.

Static-headspace (S-HS), headspace-solid phase microextraction (HS-SPME) and headspace sorptive extraction (HSSE) have been applied to the analysis of different grades of benzoin gums Siam and Sumatra. This study led to the identification of 58 compounds by GC-RI and GC-MS: 42 of them were characterized in Siam benzoin gum (grades 3 and 5) and 40 of them in Sumatra (grades B and D). SPME using divinylbenzene/carboxen/polydimethylsiloxane fiber and HSSE are complementary in these conditions and seem to be the most suitable techniques to identify volatile compounds of benzoin gums. S-HS is less sensitive but represents a good method for the quality control of these gums. For this reason it has been applied directly coupled to mass spectrometry for a rapid differentiation between several benzoin gum qualities.

For over the past 20 years, a remarkable development in the study and search of natural products has been observed. This is linked to a new market trend towards ecology and also due to new regulations. This could be a rupture, but also a real booster for creativity. Usually, in the flavor and fragrance field, creativity was boosted by the arrival of new synthetic molecules. Naturals remained the traditional, century-old products, protected by secrecy and specific know-how from each company. Regulatory restrictions or eco-friendly certification constraints like hexane-free processes triggered an important brainstorming in the industry. As a result, we developed new eco-friendly processes including supercritical CO2 extraction, allowing fresh plants to be used to obtain industrial flower extracts (Jasmine Grandiflorum, Jasmine Sambac, Orange blossom). These extracts are analyzed by GC, GC/MS, GCO, and HPTLC techniques. New or unusual raw materials can also be explored, but the resulting extracts have to be tested for safety reasons. Some examples are described.

The volatile extract composition of two different benzoin gums, Siam and Sumatra, were analysed by GC-MS. Twenty components representing more than 99.1% of the oil from Siam and 29 components representing more than 97.4% of the oil from Sumatra were analysed. The major components were benzyl benzoate (76.1-80.1%) for the two oils and benzoic acid (12.5%), methyl benzoate (1.5%) and allyl benzoate (1.5%) for Siam, and styrene (2.3%), cinnamic acid (3.5%) and benzyl cinnamate (3.3%) for Sumatra. Volatile compounds of oils and crushed benzoins were also studied using solid-phase microextraction (SPME) employing carboxen/polydimethylsiloxane and carbowax/divinylbenzene fibres.

The mixture of bark and gum obtained after size-grading of Siam benzoin gum was studied to establish its potential application as a valuable new grade of the balsamic resin. An analysis of its volatile constituents by means of static headspace and SPME led to the identification of 26 and 50 compounds, respectively. Significant differences were observed in both the headspace composition and olfactory properties of the byproduct as compared to those of Siam benzoin gum. This prompted the further analysis of its volatile extract and its resinoid by GC techniques, resulting in the identification of 60 (99.5%) and 16 (89.1%) components, respectively. To examine the influence of bark pieces, different extracts obtained from the raw material and from a sorted sample were analyzed by GC and HPLC techniques. The chemical compositions and the yields determined for the two resinoids lead to the conclusion that this harvesting byproduct is a new grade of Siam benzoin gum, providing interesting olfactory notes that differ from those of other grades.