Effect of cluster and berry thinning on Merlot and Cabernet Sauvignon wines composition
M. Karoglan, M. Osrečak, L. Maslov, B. Kozinahttps://doi.org/10.17221/598/2013-CJFSCitation:Karoglan M., Osrečak M., Maslov L., Kozina B. (2014): Effect of cluster and berry thinning on Merlot and Cabernet Sauvignon wines composition. Czech J. Food Sci., 32: 470-476.
The manipulation of grape yield is widely practised to improve grape and wine quality. Merlot and Cabernet Sauvignon vines in the Zagreb vineyard hills, north-western Croatia, were subjected to three crop removal treatments [cluster thinning (CT), berry thinning (BT), CT+BT, and untreated control] in a randomised block design experiment. CT and CT+BT treatments reduced the grape yield but increased the mean cluster weight compared to control vines. BT alone had a little effect on the yield components. Control grapes generally had the lowest soluble solids (°Oe) and highest titratable acidity (g/l). In most cases, control wines had the lowest total phenols, flavan-3-ols, and anthocyanin concentrations, while CT+BT treatment had the highest ones followed by CT treatment. It was concluded that CT+BT produced wines with generally increased total phenols, flavan-3-ols, and anthocyanins, as well as many individual phenolic compounds. Thus, grape yield per vine seems to be strongly connected with the grape and wine compositions. The final cost-effectiveness of this canopy interventions still remains questionable.Keywords:
crop removal; anthocyanins; flavan-3-ols; phenols