Physicochemical behavior of Riesling x Silvaner grapevine fruit under the high altitude conditions of Colombia (South America)

Abstract

The Valle del Sol (Sun Valley) of the Boyacá department is a zone with temperate tropical climate conditions (2,500 m above sea level) that is suitable for the production of grapes for quality wine. The objective of this investigation was to study the physical and chemical behavior during growth and development of the grapevine fruit var. Riesling x Silvaner, produced for winemaking, in the municipality of Corrales (Boyacá, Colombia). To determine the physical and chemical characteristics of the fruit starting at 28 days after anthesis (daa), 14 weekly samplings were carried out, in each of which three clusters were taken from randomly selected plants. The development of the berry lasted 119 daa in which three stages were defi ned: herbaceous, veraison and maturation1. The herbaceous stage ended at 63 daa, the veraison period lasted 14 days and ended at 77 daa, whereas the maturation and ripening stage lasted 42 days; no period of overmaturity was observed. The behavior of the fresh mass, dry mass and diameter of the fruit followed a double sigmoid curve. During berry development, total soluble solids (from 5.03 to 23.73 °Brix at the harvest point), pH (from 2.88 to 3.71) and technological maturity index (from 2.27 to 21.84) all increased, whereas total titratable acidity decreased from 3.96 to 1.11%.