RT Journal Article SR Electronic T1 Canopy Management and Enzyme Impacts on Merlot, Cabernet franc, and Cabernet Sauvignon. II. Wine Composition and Quality JF American Journal of Enology and Viticulture JO Am. J. Enol. Vitic. FD American Society for Enology and Viticulture SP ajev.2010.10035 DO 10.5344/ajev.2010.10035 A1 Frederick Di Profio A1 Andrew G. Reynolds A1 Angela Kasimos YR 2011 UL http://www.ajevonline.org/content/early/2011/02/23/ajev.2010.10035.abstract AB Merlot, Cabernet franc, and Cabernet Sauvignon vines in Niagara-on-the-Lake Ontario, were subjected to four treatments [hedged control; cluster thin at veraison (CT); basal leaf removal (BLR); CT+BLR] in a randomized complete block experiment. Musts from each treatment replicate (CT+BLR excepted) were thereafter either left untreated, or treated with one of ColorPro or ColorX enzymes. Cluster thinned and CT+BLR treatments in most cases had the highest wine anthocyanin and phenol concentrations, as well as the highest color intensities (A420 + A520). Leaf removal resulted in small increases in wine color intensity, anthocyanin and phenol concentrations. Cluster thinned and BLR treatments both reduced titratable acidity (TA) and increased pH relative to controls, but BLR tended to be more effective than cluster thinning in this respect. The CT+BLR treatments usually resulted in the lowest TA and the highest pH. Enzyme treatments increased wine TA and reduced pH, and typically increased color intensity, total anthocyanins and phenols. Both viticultural and enological treatments had noteworthy impacts on individual wine phenolic compounds and anthocyanins, although the viticultural treatments were more efficacious. The viticultural treatments enhanced intensities of several aroma and retronasal descriptors (e.g. black fruit, black pepper, tobacco) and reduced those of others (e.g. bean/pea, mushroom). The CT+BLR treatment has potential to substantially improve fruit and wine composition in cool climate regions; a negative consequence to this might be that excessive leaf removal could result in lowered ethanol, as well as undesirable increases in pH. Enzyme treatment has potential for increased color intensity, but with occasional increases in TA.