Influence of Fermentation Time on the Phenolic Compounds, Vitamin C, Color and Antioxidant Activity in the Winemaking Process of Blueberry (Vaccinium corymbosum) Wine Obtained by Maceration

Abstract

Flavonoid compounds, including anthocyanins and flavan-3-ol derivatives, total tannins, total vitamin C and resveratrol were analyzed by HPLC in blueberry fruits, their skin and pulp, as well as in wines produced from them. Two wines were elaborated, with different times of fermentation. The fruit analysis provided information on the distribution of bioactive compounds in the berries, showing that the skin had the highest concentrations of all compounds. The winemaking process needed a maceration stage to extract these compounds from skins to wine. This maceration process increased the concentration of all compounds and the antioxidant activity values measured by the DPPH assay, but long maceration times decreased the compounds and the antioxidant activity, due to the phenolic compounds that were involved in several reactions, such as polymerization, copigmentation, degradation, formation of pyranoanthocyanins and reactions between anthocyanins and tannins. The sensorial analysis of wines showed that partial fermentation wine had better characteristics than total fermentation wine, although both wines had a high acidity.

Keywords: anthocyanins; antioxidant activity; blueberry; vitamin C; wine.

Figure 1

Concentrations (mg/100 g d.m.) of 3-monogalactosides, 3-monoglucosides, 3-arabinosides and 3-pentosides derivatives of anthocyanins and anthocyanidins and flavan-3-ol derivatives in berries, skin and pulp of Windsor blueberry (means and standard deviations). Values with different superscript letters are significantly different, p = 0.01.

Figure 2

Concentration (g/100 g d.m.) of total tannins (a) and (mg/100 g d.m.) of total vitamin C (b) in berries, skin and pulp of Windsor blueberry (means and standard deviations). Values with different superscript letters are significantly different, p = 0.01.

Figure 3

Chromatograms of the anthocyanins fraction corresponding to initial juice (a), partial fermentation wine (wine PF) (b) and total fermentation wine (wine TF) (c). Anthocyanins: 1. Dp-3-gal: Delphinidin-3-galactoside; 2. Dp-3-glc: Delphinidin-3-glucoside; 3. Cn-3-gal: Cyanidin-3-galactoside; 4. Dp-3-arb: Delphinidin-3-arabinoside; 5. Cn-3-glc: Cyanidin-3-glucoside; 6. Pt-3-gal: Petunidin-3-galactoside; 7. Cn-3-arb: Cyanidin-3-arabinoside; 8. Pn-3-gal: Peonidin-3-galactoside; 9. Pt-3-arb: Petunidin-3-arabinoside; 10. Mv-3-gal: Malvidin-3-galactoside; 11. Mv-3-glc: Malvidin-3-glucoside; 12. Pn-3-pentoside: Peonidin-3-pentoside; 13. Mv-3-arb: Malvidin-3-arabinoside; 14. Pn: peonidin 15. Mv: malvidin.

Figure 4

Concentration (mg/L) of 3-monogalactosides, 3-monoglucosides, 3-arabinosides and 3-pentosides derivatives of anthocyanins and anthocyanidins and flavan-3-ol derivatives in initial juice and wines from Windsor blueberry (means and standard deviations). Values with different superscript letters are significantly different, p = 0.01.

Figure 5

Concentration (g/L) of total tannins (a) and (mg/L) total vitamin C (b) in initial juice and wines from Windsor blueberry. Values with different superscript letters are significantly different, p = 0.01.