Evaluation of the Storage Conditions and Type of Cork Stopper on the Quality of Bottled White Wines.

The effects of different storage conditions, light exposure, temperature and different commercially available cork stoppers on the phenolic, volatile and sensorial profile of Verdejo wines were studied. Two natural corks of different visual quality and a microgranulated cork stopper were investigated over one year at two different storage conditions. One simulating light exposure and temperature in retail outlets and the other simulating optimal cellar conditions (darkness and 12 °C). The wines stored under commercial conditions showed greater losses of total and free SO2 and higher levels of brown-yellowish tones, related to the oxidation of flavan-3-ols. Although these wines underwent a decrease in the total content of stilbenes, a significant increase in trans-piceid was observed. In addition, these wines suffered important changes in their volatile and sensory profile. Volatile compounds with fruity and floral aromas decreased significantly, while volatile compounds related to aged-type characters, as linalool oxides, vitispirane, TDN or furan derivatives increased. Wines stored in darkness at 12 °C underwent minor changes and their sensory profiles were similar to wine before bottling. The high-quality natural corks and microgranulated corks better preserved the quality of the white wines from a sensory point of view. These results showed that temperature and light exposure conditions (diffuse white LEDs and 24 ± 2 °C) in retail outlets considerably decrease the quality of bottled white wines and, consequently, their shelf life, due to the premature development of aged-type characters.

Effect of Wine Lees as Alternative Antioxidants on Physicochemical and Sensorial Composition of Deer Burgers Stored during Chilled Storage.

Wine lees from two grape varieties (Vitis vinifera L. Cv. "verdejo" and "palomino") were studied as natural preservatives in deer burgers compared with the traditional additive sodium ascorbate. Burgers packed in modified atmosphere packaging and stored in refrigeration were analyzed at 0, 4, 8, and 12 days. The addition of lees (2.5% and 5%) produced a reduction of pH and variations in color (L* and a*), higher antioxidant capacity and phenolic content, lower lipid and protein oxidation, and the inhibition of psychotrophic aerobic bacteria and enterobacteria during the storage time. Likewise, burgers with lees kept the aldehydes concentration (volatile compounds indicators of lipid oxidation) over storage time, while esters, acids, and other compounds, previously present in lees, increased. These changes provided new odor and taste attributes like wine, bakery, and raisin notes. Therefore, the addition of wine lees had an antioxidant and antimicrobial effect and produced new sensory attributes in deer burgers.