Grapevine row orientation, vintage and grape ripeness effect on anthocyanins, flavan-3-ols, flavonols and phenolic acids: I. <i>Vitis vinifera</i> L. cv. Syrah grapes

Phenolic concentrations are affected by environmental factors and grape cultivar, as well viticultural practices, which should be considered when a specific phenolic profile is intended. The effect of microclimate induced row orientation on compounds Vitis vinifera L. cv. Syrah/101-14 Mgt grapes was investigated. Grapes were harvested from four vintages at 22 °Brix, 24 °Brix 26 N-S, E-W, NE-SW NW-SE orientated grapevine rows. Phenolics quantified in freeze-dried skins using an HPLC method. A vintage only evident for individual phenolics the vintages. rows had highest total flavonols anthocyanins. Catechin N-S whereas acids, caffeic acid °Brix. Isoquercetin kaempferol quercitrin E-W majority results indicate that affects development Syrah grapes, but has limited phenolics. Light fruit zone positively However, it unlikely single index can applied to all growing conditions cultivars. Rows allow moderate radiation intensity canopy (i.e., during day) seem more favourable than light berry temperature resulting have potential widening range wine styles. In practice, desirable may not applicable environments. Management remains option increasing or decreasing exposure, irrespective orientation.