Effect of Rachis Position on Size and Maturity of Cabernet Sauvignon Berries

Abstract

As part of a crop forecasting study, the variability in grape berry maturity and weight within individual clusters of Cabernet Sauvignon were determined. Each cluster was weighed as a whole and the number of berries within the cluster was counted. The difference between bottom berry weight and average berry weight was found to be statistically significant. Four berries were chosen systematically from the four sides of each cluster’s top, middle, and bottom region, yielding measurements of four variates: (1) top berry Brix, (2) middle berry Brix, (3) bottom berry Brix, and (4) Brix determined by mixing the juice extracted from all of each cluster’s remaining berries. Each of the replicates of variate (4) values were then subtracted from the corresponding measurements of variates (1), (2), and (3). The mean of the bottom berries’ difference in Brix from the entire cluster’s Brix was found to differ from zero significantly. This suggests that the Brix of a cluster may be represented poorly by berries near the bottom of the cluster.