PT - JOURNAL ARTICLE AU - Kristine M. Hagen AU - Markus Keller AU - Charles G. Edwards TI - Survey of Biotin, Pantothenic Acid, and Assimilable Nitrogen in Winegrapes from the Pacific Northwest AID - 10.5344/ajev.2008.59.4.432 DP - 2008 Dec 01 TA - American Journal of Enology and Viticulture PG - 432--436 VI - 59 IP - 4 4099 - http://www.ajevonline.org/content/59/4/432.short 4100 - http://www.ajevonline.org/content/59/4/432.full SO - Am J Enol Vitic.2008 Dec 01; 59 AB - Winegrape samples were collected from 2001 to 2003 in vineyards located in the Pacific Northwest. Riesling and Chardonnay had lower concentrations of biotin (often <1 μg/L) than did red cultivars. The concentration of pantothenic acid (mean 513 ± 181 mg/L) was lowest in Riesling but highest in Chardonnay. Most samples contained low amounts of yeast assimilable nitrogen (YAN), ranging from 25 to 336 mg/L (mean 124 ± 62 mg/L). While most grape samples had adequate amounts of pantothenic acid for fermentation, many were deficient in biotin or YAN.