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In case of spices or crude drugs of medicinal- and aromatic plant origin, sensory characteristics, especially odour, has great commercial importance. The instrumental sensory analysis the so-called 'electronic nose' has proved to be a significant, new and quick method in chemometry. The sensor signal responses (data recorded by the electronic nose instrument) of the electronic nose were evaluated by statistical methods, including principal component analysis (PCA) and canonical discriminant analysis (CDA) and the combination of these methods by applying the discriminant analysis on the first eight principal components. The aim of this paper is the comparative analysis of the above evaluation methods as data processing tools of the sensor signal response of the electronic nose (chemosensor array). The essential oil of oregano (Origanum vulgare subsp. hirtum) selected line No. 10 was compared to the oil distilled from the selected line No. 11; and dried root samples of lovage (Levisticum officinale) harvested at different times from the two- and three-year-old population, were investigated with electronic nose (NST-3320, AppliedSensor Sweden AB). Principal component analysis, as a first step of the evaluation, did not clearly distinguish either oregano or lovage samples. Further statistical evaluation of the original sensor signal responses of the electronic nose with canonical discriminant analysis improved the separation power of the model. The best separation could be achieved by the combination of the two methods, whereby canonical discriminant analysis was applied to the first eight principal components, which described 99% of the differences. In all cases more than 92%, while in several experiments 100% of cross-validated grouped cases were classified correctly. Based on the results, the application of the electronic nose and the combination of multivariate methods, PCA and CDA, could be an appropriate tool either for identification of cultivar to accelerate selection process or to distinguish crude drugs of different age or different harvesting period.

Oregano is used worldwide both as spice and crude drug, which is mainly provided by species of Origanum genus. The quality of the product is usually determined by chemical analysis, whereas in food industrial applications sensory tests are also practised. The aim of the present study was a comparison of parallel quality investigations of oregano samples by a new and effective instrumental sensory evaluation method, the “electronic nose”, and by gas-chromatographic and human sensory analysis. The GC analysis of essential oil components revealed mainly differences between plant species (Origanum vulgare subsp. hirtum and Origanum majorana). Main components of the oil of the former taxon are carvacrol and thymol, while those of marjoram are terpinene-4-ol, ?-terpinene and terpinolene. A wholesale oregano sample showing considerable divergence from the other ones with respect to ratios of carvacrol, ß-caryophyllene ß-cubebene and thymol. It was assumed not to belong to ssp. hirtum. The electronic nose analysis, evaluated by PCA, proved to be an appropriate, rapid, non-destructive, reagent-less method for the reliable separation of all of the oregano samples based on their complex aroma features. Assumptions could be made about correlations between separation of samples by the instrumental sensors and proportions of terpenoid compounds of the oil established by GC in some cases only. The varying essential oil content of the samples did not influence the success of instrumental evaluation. The instrumental and human sensory analysis showed similar results: varieties of O. majorana could be well distinguished on the basis of their complex aroma, while their gas-chromatograms did not show characteristic differences. The results call the attention that quality evaluation of drug items of aromatic plants should be oriented in different directions, considering the current utilisation area of the items. 

To raise the efficiency of plant regeneration we studied the important and necessary elements of the procedure. The embryogen capacity of 33 various grape genotypes were tested on four different induction media. We successfully obtained anther derived embryogenic calli in 27 genotypes with the range of 1–12%, this is the first reported protocol for embryogenesis from Korai bíbor, Odysseus, Orpheus and Pannon frankos cultivars. Two sorts of sterilization treatments were examined before inducing somatic embryos. For optimisation of grape regeneration system the propagation of calli was attempted in Richter 110 cultivar, there was no any significant differences in the measured values, but CPE medium proved more successful in maintaining embryogenic capacity of callus. We experienced high developmental differences between the propagated embryogenic culture of Richter 110, Teleki 5C and Chardonnay derived from MSNOA liquid medium and from MSE solid medium. Regenerated plants from embryogenic callus were obtained in 21 genotypes, in Chardonnay cultivar CP medium influenced more positively the plant regeneration than the MS/2 medium.

In the case of a widely used spice — Origanum vulgare subsp. hirtum — the effect of different drying methods (natural, and by using dryers at temperatures of 30°C, 40 °C, 45°C) was investigated referring to the essential oil amount and composition in the final material. The sensory characteristics of olive oils flavoured by the oregano samples were also determined. The essential oil amount and the area percentage of its main component — carvacrol — were significantly influenced by the different drying temperatures. Compared to the natural way of drying in the case of the essential oil content the drying temperature of 40°C and 45°C was preferable for the higher amounts. Referring to the carvacrol area percentage the drying temperature of 30°C resulted in the highest amounts (89.74±0.28%), that was affirmed by the sensory analysis as well; based on the taste descriptions the consumers found it the most pungent one. According to our results sensory analysis data in most of the cases corresponds to the GC-MS measurements and give a much more complex characterisation of a spice.