## 3 Results
The opposite happened for the aliphatic acids which showed in these varieties the lowest amount. As regards aliphatic acids and higher alcohols, a limited influence on the wine aroma has been demonstrated probably due to their high OTV [19] and water solubility; they contribute to the general complexity of wine aroma, but they are not able to inhibit the perception of other volatile compounds [19]. Pre-fermentative aroma, namely C6 alcohols, have been identified and the highest amount occurred for MR samples. They arise from membrane lipids through the lipoxygenase pathway during technological operations prior to the fermentation, as well as during heating of must heating or grape meration. Their concentration depends on grape variety, ripeness stage, treatments prior to fermentation, and temperature/duration of contact with the skins. At a low concentration, they contribute positively to the overall aroma of the wine [18]. Although the volatile compounds generated in the fermentation process are usually the most important contributors to the overall aroma of the wine, the varietal aroma compounds originating in the vine play a fundamental role in the characteristics of many wines, among these, mainly Muscat wines. Indeed, terpen, that are among the main varietal aroma contributors, have been detected in the highest amount in Moscato grapes; they can contain more than 5 mg/kg of terpen, with linalool and geraniol the main ones [20]. Figure 1 reports a chromatogram of a Moscato wine sample in SIM mode (\(m/z\): 93.00 + 121.00 + 136.00). As shown in Figure 1, it is possible to verify the presence of a large number of terpenes, both hydrocarbons and oxygenated monoterenes, and some were identified here for the first time. Considering the amount of each varietal aroma, a different composition resulted between the varieties not only for the amount of each volatile but also for the ratio among these. In all the varieties linalool, geraniol and trans-linalool oxide (furanoid form) were  
Figure 1: HS-SPME-GC-MS (head space-solid phase micro extraction-gas chromatography-mass spectrometry) profile in SIM (selected ion monitoring) mode (\(m/z=93.0\) + 121.0 + 136.0) of a fortified Moscato Giallo wine sample. the main compounds among terpenes. Linalool had the highest concentration in MG, MO, and MR wines whereas geraniol was more prevalent in MB and MBPG wines. Our data are comparable only with those of [PERSON] et al. [8] who analyzed the amount of free and glycosylated monoterpenes in fortified Moscato nero d'Aqui wines using SPME-GC-MS; the total amount of terpenes is comparable with our results even if the amount of each terpene was different. In particular, Moscato Nero fortified wines have been characterized by a high amount of citronellol that prevailed among the other terpen [8]. In our samples the total amount of terpenes ranged between 286 and 811.7 ug/L with the highest value in MG and MO wine samples (Figure 2). This content was higher than that reported by [PERSON] et al. in fortified wines [8]. Terpenes accumulate in the berry during ripening and are mainly responsible for the Moscato aroma [21]; the wines obtained from Moscato varieties are in fact defined as aromatic wines due to the high number of monoterpenes, both hydrocarbons and oxygenated [6]. Among C\({}_{13}\)-norisoprenoids, 6-methyl-5-hepten-2-one and geranyl acetone have been identified; these substances arise from the carotenoid degradation. The highest amount of these compounds was found in MR wines. The ratio among the esters (fruity notes) and the terpenes (floral notes) is reported in Figure 2 showing interesting differences among varieties: the amount of esters was 2.5-3 times higher than terpenes in yellow varieties (MG and MO), 4.3-5-times higher in white varieties (MB and MBPG), less than 2 times in MR.