Determination of free amino acids in wine by high performance liquid chromatography
Sanders, E.M.; Ough, C.S.
American Journal of Enology and Viticulture 36(1): 43-46
A method of analysis is presented which separates 20 derivatized amino acids in under 35 min. Prior to derivatization, white wine samples from a fermentation temperature study were filtered and passed through a C18 Sep-Pak in 0.1% trifluoroacetic acid in 70:30 water:methanol. During a 2 min reaction period, a fluorescent derivative was formed between the amino acid and an o-phthaldialdehyde (OPA)/.beta.-mercaptoethanol reagent. The derivatized amino acids were then separated on a Resolve, 15 cm (5 .mu.m) column. Recoveries following clean-up and analysis ranged from 77.5-100% and were very reproducible. Good agreement was found between results from an amino acid analyzer and the high peformance liquid chromatography OPA method.