PT - JOURNAL ARTICLE AU - Mark A. Kelm AU - Andrea Versari AU - Giuseppina Paola Parpinello AU - John H. Thorngate III TI - Mass Spectral Characterization of Uva Longanesi Seed and Skin Extracts AID - 10.5344/ajev.2012.12017 DP - 2012 Sep 01 TA - American Journal of Enology and Viticulture PG - 402--406 VI - 63 IP - 3 4099 - http://www.ajevonline.org/content/63/3/402.short 4100 - http://www.ajevonline.org/content/63/3/402.full SO - Am. J. Enol. Vitic.2012 Sep 01; 63 AB - Polyphenolics in grape seed and skin extracts of Uva Longanesi were analyzed at harvest with selected chromatography techniques. Seed extract of Uva Longanesi was characterized by high content of proanthocyanidins (average 49 g/100 g extract), of which 42% was polymeric and ~28% was oligomeric. Epicatechin comprised the primary extension subunit (~75%), whereas catechin predominated as the terminal unit (~67%); epicatechin-gallate was present in both extension (~11%) and terminal subunits (~9%). As skins matured, terminal unit galloylation decreased and extension unit galloylation increased. The mean degree of polymerization of seed proanthocyanidins was relatively constant (average 2.7 subunits) across the sampling dates.