Changes in amino acids and phenolic compounds in Emir, Narince, and Sultaniye grapes were monitored by high-performance liquid chromatography for two consecutive seasons. | Turkish Journal of Agriculture and Forestry Research Article Turk J Agric For (2015) 39: 984-991 © TÜBİTAK doi: Seasonal variation in amino acid and phenolic compound profiles of three Turkish white wine grapes 1, 2 3 4 M. Ümit ÜNAL *, Aysun ŞENER , Kemal ŞEN , Murat YILMAZTEKİN Department of Food Engineering, Faculty of Agriculture, Çukurova University, Balcalı, Adana, Turkey 2 Department of Food Engineering, Faculty of Engineering, Adıyaman University, Altınşehir, Adıyaman, Turkey 3 Department of Food Engineering, Faculty of Engineering and Architecture, Nevşehir Hacı Bektaş Veli University, Nevşehir, Turkey 4 Department of Food Engineering, Faculty of Engineering, İnönü University, Malatya, Turkey 1 Received: Accepted/Published Online: Printed: Abstract: Changes in amino acids and phenolic compounds in Emir, Narince, and Sultaniye grapes were monitored by high-performance liquid chromatography for two consecutive seasons. Seasonal and varietal variations in amino acid content were observed among the cultivars. Arginine, histidine, and alanine were the most prominent amino acids in all 3 cultivars in both years, with arginine being the highest found in the Sultaniye cultivar, varying between 910 and 955 mg/L. The phenolic contents also showed seasonal and varietal variations. Of the phenolic compounds identified, catechin was the most abundant in all three cultivars, with the highest found in Narince ranging between 106 and 109 mg/kg. Procyanidin B1 and gallic acid were the second most prominent. Key words: Amino acid, phenolics, seasonal change, grape, wine 1. Introduction Free amino acids and ammonia account for the majority of the nitrogen-containing compounds that are, next to sugars, quantitatively the most important yeast nutrients in wine grapes for successful alcohol and/or malolactic fermentation. Yeast growth, fermentation rate, fermentation .
