RT Journal Article SR Electronic T1 Survey of Biotin, Pantothenic Acid, and Assimilable Nitrogen in Winegrapes from the Pacific Northwest JF American Journal of Enology and Viticulture JO Am J Enol Vitic. FD American Society for Enology and Viticulture SP 432 OP 436 DO 10.5344/ajev.2008.59.4.432 VO 59 IS 4 A1 Kristine M. Hagen A1 Markus Keller A1 Charles G. Edwards YR 2008 UL http://www.ajevonline.org/content/59/4/432.abstract 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.