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Among the Moscato grapes, Moscato Giallo is a winegrape variety characterised by a high content of free and glycosylated monoterpenoids, which gives wines very intense notes of ripe fruit and flowers. The aromatic bouquet of Moscato Giallo is strongly influenced by the high concentration of linalool, geraniol, linalool oxides, limonene, α-terpineol, citronellol, hotrienol, diendiols, trans/cis -8-hydroxy linalool, geranic acid and myrcene, that give citrus, rose, and peach notes. Except for quali-quantitative analysis, no investigations regarding the isotopic values of the target volatile compounds in grapes and wines are documented in the literature. Nevertheless, the analysis of the stable isotope ratio represents a modern and powerful tool used by the laboratories responsible for official consumer protection, for food quality and genuineness assessment. To this aim, the aromatic compounds extracted from grapes and wine were analysed both by GC-MS/MS, to define the aroma profiles, and by GC-C/Py-IRMS, for a preliminary isotope compound-specific investigation. Seventeen samples of Moscato Giallo grapes were collected during the harvest season in 2021 from two Italian regions renowned for the cultivation of this aromatic variety, Trentino Alto Adige and Veneto, and the corresponding wines were produced at micro-winery scale. The GC-MS/MS analysis confirmed the presence of the typical terpenoids both in glycosylated and free forms, responsible for the characteristic aroma of the Moscato Giallo variety, while the compound-specific isotope ratio analysis allowed us to determine the carbon (δ 13 C) and hydrogen (δ 2 H) isotopic signatures of the major volatile compounds for the first time.

A novel preparative-scale triple gas chromatographic system, equipped with three Deans-switch devices, is herein described. The isolation of volatile compounds was achieved by using a lab-made collection system. Considerations are made on the possibility to inject high volumes of neat sample, maintaining, at the same time, high resolution levels. The degree of recovery of a series of compounds, characterized by a differing volatility, is also reported. In this respect, different collection conditions were evaluated, namely, the presence (or not) of packing material as well as CO(2) cooling, in various combinations. Finally, the interconnected features, that is time requirements and the isolation of "acceptable" analyte quantities (e.g., milligram level for NMR characterization), are related to parameters such as analyte concentration, injected volume, collection conditions, and number of GC runs. The results herein reported will demonstrate the need for a high-resolution GC step, prior to analyte collection, in the prep-GC analysis of complex samples.

Numerous samples of Italian cold-pressed bergamot oils, representative of the industrial production of the last three seasons (2008/09, 2009/10 and 2010/11), as well as several samples of bergapten-free, concentrated and recovered oils, have been extensively investigated in the present study. The samples were analyzed to determine the composition of the volatile fraction, the oxygen heterocyclic compounds, the enantiomeric distribution of twelve volatile components and the isotopic ratios of selected volatiles. Differences from previous studies emerged. The recent improvement in cultural practices is confirmed by the increase of linalool and linalyl acetate, indicative of better quality of the essential oils. The seasonal variation of the enantiomeric excess of α-terpineol, characteristic of cold-pressed bergamot oils, is confirmed. Some oxygen heterocyclic compounds are here quantitatively determined for the first time. The presence of herniarin is confirmed in genuine samples through high-pressure liquid-chromatography--mass spectrometry-ion trap--time of flight (HPLC-MS-IT-TOF). The isotopic ratios herein reported, tbr all the samples analyzed, represent a useful tool for the evaluation of genuineness of cold-pressed and processed bergamot oils. [ABSTRACT FROM AUTHOR]

White truffle ( Tuber magnatum Pico ) is one of the most valuable delicacies of the Italian and French cuisine. Previous works on truffle aroma report sulfur compounds and short-chain aldehydes as typical constituents which abundance is influenced by storage conditions. In this study, the head space of truffle aroma has been evaluated by two different (innovative) approaches: HS-SPME extraction and comprehensive two-dimensional gas chromatography (GCxGC), exploiting a dual-stage loop-type modulator within a GC system with simultaneous FID and MS double detection, analysis and Gas sensors array system analysis. Gas chromatographic peak identification was carried out by means of dedicated laboratory-made GC–MS libraries and comparison of Retention Indices with those retrieved from literature, while peak quantification by means of a specifically designed software for comprehensive GC. The truffle samples were stored at +8 °C for four days in three different ways: wrapped in blotting paper or covered by rice or under vacuum. Eighty compounds were identified with high confidence (>90% of mass spectra similarity). PCA of compounds relative percentages showed differences among the fresh product and truffles stored in rice and under vacuum; on the contrary no significant volatiles composition modification was observed for truffles stored in paper. [ABSTRACT FROM AUTHOR]