RESUMEN
The influence of different combinations of Syrah grape maturation degree (19, 21 and 23⯰Brix) and maceration times (10, 20 and 30â¯days) on the volatile profile and aroma potential was evaluated for the first time through different chromatographic platforms (GCâ¯×â¯GC/TOFMS, GC-O-OSME, GC-FID and GC/MS). GCâ¯×â¯GC/TOFMS analyses resulted in 145 identified compounds and among these 29 were determined to be the most important for wine differentiation. The aroma compounds allowed the discrimination of Syrah wines made with grapes macerated for a shorter time (ten days) due to the higher levels of volatile compounds. The evaluation of these wines through GC-O-OSME together with GC-FID, MS resulted in the designation of 19⯰Brix as the most appropriate grape maturation degree to obtain a greater number of volatiles with pleasant odor and higher intensity and persistence. GCâ¯×â¯GC/TOFMS allowed five and six co-elutions to be resolved, involving, respectively, ten and twelve important wine compounds.
Asunto(s)
Odorantes/análisis , Vitis/química , Vino/análisis , Cromatografía de Gases y Espectrometría de Masas/métodos , Olfatometría , Compuestos Orgánicos Volátiles/análisisRESUMEN
São Francisco River Valley (SFRV) is a wine-producing semi-arid region in Brazil. Therefore, we used a 1H NMR and UPLC-MS-based metabolomic approach coupled to chemometrics to evaluate the variability in Chenin Blanc and Syrah wines for two harvest seasons, two vine training system and six rootstocks. Overall, the secondary metabolites were influenced by the three factors studied, whereas the primary metabolites were only by the seasonality. Chenin Blanc wines made in December presented higher content of an unidentified carbohydrate. In Syrah wines, glycerol, tartaric acid, succinic acid and 2,3-butanediol were greater in December, while proline and lactic acid were more abundant in July. For training system, caffeic acid derivatives were increased in wines produced from espalier. Lyre system increased phenolic compounds, organic acids and apocarotenoids. The effect of the rootstocks was less pronounced, affecting basically caffeic acid derivatives. Thus, we expect that our results may assist the winemakers to improve the SFRV wine quality.