PT - JOURNAL ARTICLE AU - DOUGLAS R. WEBSTER AU - CHARLES G. EDWARDS AU - SARA E. SPAYD AU - JOHN C. PETERSON AU - BARBARA J. SEYMOUR TI - Influence of Vineyard Nitrogen Fertilization on the Concentrations of Monoterpenes, Higher Alcohols, and Esters in Aged Riesling Wines AID - 10.5344/ajev.1993.44.3.275 DP - 1993 Jan 01 TA - American Journal of Enology and Viticulture PG - 275--284 VI - 44 IP - 3 4099 - http://www.ajevonline.org/content/44/3/275.short 4100 - http://www.ajevonline.org/content/44/3/275.full SO - Am J Enol Vitic.1993 Jan 01; 44 AB - Riesling wines produced in 1986 and 1988 from vines fertilized with 0, 56, 112, or 224 kg N/ha/year were analyzed in 1991 for free and bound monoterpenes, higher alcohols, and esters. Solid phase extraction using AmberliteĀ® XAD-2 resin was employed in the isolation of volatile compounds identified by gas-liquid chromatography/mass spectrometry. Relative recoveries of all compounds ranged from 79% to 112% with coefficients of variation generally less than 7%. Vineyard N fertilization affected the concentration of some free or bound monoterpenes in the aged wines, depending on the monoterpene and vintage. Concentrations of amyl alcohols and 2-phenylethanol decreased with increasing N fertilization while isobutanol and cis-3-hexen-1-ol showed no differences. Concentrations of 1-butanol, trans-3-hexen-1-ol, benzyl alcohol, and the majority of esters increased (p < 0.05) with increased N fertilization. Sensory analysis using triangle difference tests indicated that wines made from grapes fertilized with 0 or 224 kg N/ha significantly differed (p < 0.01).