Aromatic complexity in Verdicchio wines: a case study

Aim: Verdicchio is a white wine grape variety that has been cultivated for hundreds of years in the Marche region of central Italy. Verdicchio is used to produce all kinds of dry, sweet and sparkling wines, some of which can be aged for ten or more years. This study aimed to extend knowledge of the volatile profile of Verdicchio wines and the recognition and detection of odorous molecules. We considered wines produced in multiple vintages from some of the best Cru from the Marche region, in the Castelli di Jesi Classico area. Methods and results: Two data sets were considered: a vertical collection that included wines from different vintages, same variety, different production areas vinified by the same winery and a horizontal collection of wines from the 2016 harvest, considering different production areas, harvest times and clones produced by the same winery. Samples were analysed with GC×GC-ToF-MS, GC-MS-MS and GC-O. Comprehensive profiling with more than 1000 compounds allowed the wines produced in different areas to be separated. By GC-O analysis 48 main odorants were found. This survey led to the identification of 3-methyl-2,4-nonanedione (3-MND) that impart an anise note and an interesting content in methyl salicylate as a possible key odorant characteristic in Verdicchio. Conclusion: The volatile profile of different Verdicchio wines from the best production areas was investigated in detail. This work confirms that it is possible to obtain wines with very different characteristics from this variety of grapes, producing premium wines with a distinctive pattern of volatiles, reproducible across several vintages and variable depending on the different location of the vineyard and winemaking techniques. Young wines are characterised by fruity, thiolic notes, while wines aged for longer are distinguished by their norisoprenoids content and by anise and balsamic notes, which can be attributed to the presence of 3-MND and to methyl salicylate released by precursors. With a derivatisation GC-MS-MS method it was possible to quantify 3-MND in the range of 10–50 ng L−1. With the use of GC-O, 48 potentially odour-active compounds were found for this wine. Analysis of the compounds after hydrolysis confirmed that a high amount of methyl salicylate characterised this variety. Methyl salicylate has a balsamic note from wintergreen oil that is often perceived in aged Verdicchio tasting.