Changes during storage in conventional and ecological wine: phenolic content and antioxidant activity.
Polyphenol content, free radical scavenging capacity, and changes during storage over 7 months in the dark were studied in ecological and conventional red and white wines. In red wines, the most changeable components during storage were the anthocyanins since during storage anthocyanins content decreased 88% in conventional wine and 91% in ecological wine. Initially, the total flavonol contents of the conventional and ecological red wines were 163.88 +/- 2.69 and 153.58 +/- 1.71 mg/L, respectively, and no significant variations occurred during storage. No differences in hydroxycinnamic acid derivatives content between conventional and ecological red and white wines were observed. The flavonol level in white wines was very low, as expected since these compounds are found in grape skin. The initial antioxidant activity was 5.37 +/- 0.14 and 5.82 +/- 0.31 mM equivalents Trolox for conventional and ecological red wines, respectively; no significant differences were observed (p = 0.2831), and these values were 7-8 times higher than the antioxidant activity observed in conventional and ecological white wine. In contrast with other studies, the total concentrations of phenolic compounds in conventional and ecological red and white wines were not related to antioxidant activity (p > 0.05). In red wines, no significant differences were observed in the antioxidant activity of ecological and conventional red wine (p = 0.28), while in white wine significant differences were observed in the antioxidant activity between conventional and ecological white wine (p = 0.006).
Zafrilla
Pilar
P
Escuela Universitaria de Nutrición Humana y Dietética, Universidad Católica San Antonio, Murcia 30107, Spain. mpzafrilla@pdi.ucam.edu
Morillas
Juana
J
Mulero
Juana
J
Cayuela
José M
JM
Martínez-Cachá
Adela
A
Pardo
Francisco
F
López Nicolás
José Manuel
JM
D000872:Anthocyanins / Q000032:analysis; D000975:Antioxidants / Q000032:analysis*; D003373:Coumaric Acids / Q000032:analysis; D003624:Darkness; D005419:Flavonoids / Q000032:analysis*; D044948:Flavonols / Q000032:analysis; D005519:Food Preservation / Q000379:methods; D010636:Phenols / Q000032:analysis*; D059808:Polyphenols; D013997:Time Factors; D014920:Wine / Q000032:analysis*
D000872:Anthocyanins; D000975:Antioxidants; D003373:Coumaric Acids; D005419:Flavonoids; D044948:Flavonols; D010636:Phenols; D059808:Polyphenols