Basil (Ocimum basilicum L.) leaves were dried using a microwave oven at atmospheric pressure or two traditional methods: air-drying at 50 degrees C and freeze-drying. The microwave-drying was carried out at different powers and times on raw basil leaves, while for air and freeze-drying techniques, both raw and blanched leaves were used. The raw and dried basil was analyzed for selected aroma compounds by gas chromatography/mass spectrometry-selected-ion-monitoring, the chlorophyll a and b by HPLC and the color by a reflected-light colorimeter. For dried samples microwaved for 1 min at 270, 2 min at 440, 1 min at 650, and 1 min at 1100 W, the percentage retentions of the characteristic volatile compounds (eucalyptol, linalool, eugenol, and methyl eugenol) were higher than in the samples dried by traditional methods, with the exception of freeze-dried unblenched basil. Microwave drying allowed a larger retention of chlorophyll pigments than air-drying and freeze-drying (with or without blanching) and preserved the color of the raw basil. Microwave drying requires a much shorter treatment and implied the simultaneous blanching of the material.

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The quality parameters of muskmelon (Cucumis melo L var reticulatus Naud) are often related to sugar content and aroma composition. A study of aroma composition using two different extraction techniques (GC-HS and GC-MS extraction concentration) was performed in order to find correlations with sensory descriptors, other quality indices and ripening stage. Two muskmelon varieties (Calypso and Pamir) were assayed at three different ripening stages (unripe, ripe, overripe). Chemical, physical and sensory analyses were performed on the muskmelon samples just after harvest and after 7 days of cold storage. Solid soluble content (SSC) changed from about 10 • Bx in unripe samples to about 15 • Bx in ripe and overripe samples. Different aroma composition and sensory evaluation were found depending on the ripening stages. The main flavour components detected were esters which increased 10-15-fold from unripe to ripe and overripe stages. The acceptance judgements by panellists were strongly correlated with the sensory descriptor flavour. High statistical correlations were also found between sensory descriptor flavour and some classes of aroma compounds, mainly with total esters (about 0.66-0.69), formates (0.70) and acetates (0.64 and 0.72). The paper demonstrates that some classes of esters are very important to assess the sensory flavour and overall eating quality of muskmelons.

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