Bijdrage tot de kwalitatieve en kwantitatieve bepaling van aromakomponenten in de bloemen van "Azalea indica" /

Diss. lic

New method for quantitative essential oil analysis

A new method for quantitative essential oil analysis, using combined steam distillation-extraction is described. The construction of the micro-version apparatus is such that all the volatile material is collected in only 1 ml of dichloromethane containing a suitable internal standard. The main advantage is that no further enrichment by evaporation is required. The method allows the quantitative analysis of total essential oil content and the percentage of the individual compounds in less than 4 h, including sample preparation, steam distillation-extraction and capillary gas chromatographic analysis

A new method for the quantitative analysis of organochlorine pesticides and polychlorinated biphenyls

A simple method is described for the quantitative determination of organochlorine pesticides and polychlorinated biphenyls (PCB's) in water at the sub-ppb level. A micro gas-phase extractor advantageously replaces other preconcentration and purification techniques. The extract is analyzed by capillary gas chromatography without further enrichment. The recovery at the ppb level was nearly 100% for organochlorine pesticides and more than 80% for PCB's. The complete procedure including sample preparation, steam distillation-extraction, and capillary gas chromatographic analysis is carried out in less than four hours

Odour evaluation, fraction collection and preparative scale separations with glass capillary columns

A simple but effective GC approach to odour evaluation and fraction collection with capillary columns is described. An allglass device splits the column effluent, with one splitter arm going to an FID. For odour evaluation, the other splitter arm is led via teflon tubing to the nose. Off-line heart-cutting is carried out by collecting the split effluent on a glass capillary microtrap, the inner walls of which are coated with OV-101. This allows recovery of nanogram amounts of material. Multipass operation or repeated collection leads to preparative capillary GC for further spectroscopic investigation. These techniques do not involve sophisticated equipment or valves. Applications of this type of smell analysis, heart-cutting and enrichment in the analysis of Rhododendron fragrantissimum essential oil, black pepper essential oil and hop essential oil, illustrating the versatility of the systems, are presented

Chromatographic investigation of jasmin absolutes

Several Jasmine (oil) samples of different origin were studied by glass capillary gas chromatography (CGC) and by CGC—mass spectrometry. Only quantitative differences were observed. There are only 15 major components. Avout 100 minor constituents were identified after fractionation by partial evaporation, preparative gas chromatography and chemical group separation. The concentration of important smell contributing compounds is lower in the French oil sample than in the other oils. In the head space or most volatile fraction this situation is reversed. This is ascribed to the enhancing and fixating effects of the less volatile fractions of the oils. A new way to study such effects is proposed