A Simple and Fast Method for Arginine Determination in Grape Juice
HUA LI1*, XINHONG LIANG1,2, LIDAN FENG1, YANLIN LIU1 AND HUA WANG1
1. College of Enology, Northwest University of Agriculture and Forestry, Yangling 712100, Shaanxi Province, China
2. School of Food Science, Henan Institute of Science and Technology, Xinxiang 453003, Henan Province, China
(Received: April 25, 2007; Accepted: October 18, 2007)
Arginine in grape juice can be metabolized by wine yeasts and malolactic bacteria to precursors of ethyl carbamate, a known carcinogen. The aim of this study was to develop a simple, fast and accurate method for determining arginine in grape juice with Sakaguchi reaction following the separation of arginine with Amberlite IR120 strong cation-exchange resin. Measurement was done under optimized conditions as follows: sample (mg) to cation-exchange resin (g) ratio of 0.683, sample pH 2.0, sample flow rate 0.5 mL/min, use of distilled water rinsing to avoid interference of other compounds adsorbed on the resin, and elution with 1 mol/L of NaOH solution. This method can be applied in a quick and accurate quantification of arginine in grape juice for controlling the ethyl carbamate level in wine.
Key words: grape juice, arginine, ion-exchange, ethyl carbamate, Sakaguchi reaction