Spearmint (Mentha spicata L.) was dried using three different drying methods: oven-drying at 45 degrees C, air-drying at ambient temperature, and freeze-drying. The effect of the drying method on the volatile compounds and on the structural integrity and sensory characteristics of the spice was evaluated. The volatile components from fresh and dried spearmint samples were isolated by simultaneous distillation-extraction (SDE) and analyzed by gas chromatography-mass spectrometry (GC-MS). A total of 28 compounds were identified, carvone, limonene, and 1,8-cineole, in that order, being the main components in all of the samples. Oven-drying at 45 degrees C and air-drying at ambient temperature were the methods that produced the best results. An increase in monoterpenes was observed in all of the dried samples, except in the freeze-dried samples that underwent freezing at -198 degrees C. Freeze-drying resulted in substantial losses in oxygenated terpenes and sesquiterpenes. The effect of each drying method on leaf structure was observed by scanning electron microscopy. From a sensory standpoint, drying the spearmint brought about a decrease in herbaceous and floral notes together with an increase in minty odor.

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-Manchego cheese, produced from local ewe's milk in the La Mancha region of Spain under a Protected Designation of Origin (PDO), is Spain's most popular cheese variety and may be made from raw milk (artisanal cheese) or pasteurised milk (industrial cheese). As a consequence, the cheeses so manufactured may show differences in their organoleptic properties, associated with differences in volatile composition, important for cheese aroma. Samples of Manchego cheese made from raw milk and from pasteurised milk and aged for 2, 4, 6 and 12 months were analysed in this study of the volatile composition of the different cheese types, performed using two different analytical methods, Simultaneous Distillation Extraction (SDE) and Automatic Dynamic Headspace (P&T). Approximately 79 compounds were detected by SDE and 44 by headspace, falling in the chemical groups free fatty acids (FFAs), ketones, esters, alcohols and others. Also, olfactory profiles of the cheese samples were assessed by sensory analysis. Nine odour attributes (odour intensity, milk odour, lactic/yoghurt odour, briny odour, rancid odour, butter odour, dry hay odour, fruity odour and pungent sensation) were assessed sensorially. Both the concentrations of the volatile compounds detected and the intensity of the sensory odour attributes evaluated were found to vary during ripening. The results were distinctly different for the artisanal and industrial Manchego cheese samples.Manchego cheese / ripening / volatile compound / sensory analysis Résumé -Relation entre les composés volatils et l'arôme dans les fromages Manchego artisanaux et industriels. Le fromage Manchego d'Appellation d'Origine Protégée (AOP) est la variété la plus connue en Espagne. Sa production est limitée à la région de la Mancha. Ce fromage est fabriqué 613