Evolution of physico-chemical and sensory characteristics of Minutolo white wines during aging in amphorae: A comparison with stainless steel tanks

The work was aimed to evaluate the effects of aging on physico-chemical indices and antioxidant compounds of Minutolo wines produced through a traditional white vinification and kept for 12 months in 3 types of amphorae (raw, glazed, and engobe) and in stainless steel tanks. The concentrations of all the organic acids remained unchanged. The loss of flavonoids was in the range 35% (raw and glazed amphorae, stainless steel tanks)-45% (engobe amphorae). Flavans reactive with vanillin decreased by 66% in engobe amphorae and by 81% in raw amphorae. The decreases occurred in raw amphorae and stainless steel tanks were included in that range. The highest decrease of the antioxidant capacity measured through the ABTS assay was observed in raw amphorae (20% less than the starting value). The antioxidant capacity was mainly correlated to the concentrations of flavans reactive with vanillin (R⁠2=0.845). According to the Principal Component Analysis, the wines were homogeneously grouped as a function of the type of container. From a sensory point of view, aging time affected limpidity and minerality while the type of container influenced minerality, gustatory-olfactory intensity, structure, and harmony. The wines aged in raw amphorae were judged as the best

Effects of the treatment with oak chips on color-related phenolics, volatile composition, and sensory profile of red wines: the case of Aglianico and Montepulciano

The effects of the treatment of two important Italian wines, Aglianico and Montepulciano, with French oak chips were analyzed. The study was focused on the changes of color-related compounds such as anthocyanins and tannins, and of volatile and sensory profiles. An overall characterization of the wines was also performed. With reference to the phenolic profile, the behaviors of the two wines were different due to their different initial phenolic composition. The oak-chip treatments favored the polymerization of anthocyanins and tannins, whose concentrations in the oak-treated Aglianico samples were lower than in the controls (anthocyanins, â\u88\u9284 %; tannins, â\u88\u9271 %), while in the oak-treated Montepulciano wine the decrease concerned only anthocyanins (â\u88\u9257 %). The concentrations of polymeric phenols increased with aging in all the samples and, after 12 months, were higher in oak-treated wines than in the controls (+43 % in Aglianico, +39 % in Montepulciano). After 12 months of aging, the volatile profile of Aglianico oak-treated wines highlighted the highest acid (+68 %), terpene (+371 %), and lactone (+60 %) concentrations, while the oak-treated Montepulciano wine showed higher acid (+15 %), alcohol (+5 %), and lactone (+50 %) concentrations than the control wine. The sensory profile of the treated wines was characterized by high scores assigned to astringency and appearance of the typical oak aromas (woody, vanilla, and spicy notes) and the attenuation of floral and fruity attributes. These changes were responsible for the increase in intensity of the tannic character in Aglianico wine and the improvement of the Montepulciano wine aroma with respect to the corresponding untreated wines