Physicochemical characterization of ‘pinot noir’ grapevine (vitis vinifera l.) fruit during its growth and development under high altitude tropical conditions

Abstract

Although native of temperate climates, grapevines are grownin Colombia in the department of Boyaca, between 2,200 and2,560 m a.s.l. Under these specific conditions, both the physicochemicalbehaviorof the fruit and its optimum harvest timeas measured in growing degree days (GDD) had remained unknownso far. On these grounds, in the municipality of Nobsa(Boyaca, Colombia),grapevines of the variety Pinot Noir werephysico-chemically characterized during their growth anddevelopment. Since day 21 after anthesis (DAA ) until overripening,the physicochemical characteristicsof 20 berries fromeach of three clusters we collected every week were carefullyassessed. A total of 826.2 GDD accumulated during fruit growthand development, thus completing 126 DAA . The accumulationof both fresh and dry mass followed double sigmoid curves.During early growth there was a decrease in pH, total solublesolids (TSS ) and technological maturity index (TMI =TSS /TTA ), coupled to an increase in total titratable acidity (TTA ).After this period and until harvest, pH, TSS and TMI increasedwhile TTA declined. Based on fresh mass, SST and TMI it waspossible to set optimum harvest time at 800.6 GDD.