The present study reports on the development and application of a hydrophilic interaction liquid chromatography (HILIC) method for the separation of quinic acid (QA) in food matrixes. QA is a cyclohexanecarboxylic acid (mw 192 Da) evidenced in Quina (cinchona bark), cranberry, coffee beans and coffee beans-derived products [1,2]. QA is naturally found free or bound in chlorogenic acids and it is thought to be involved in the perceived acidity of coffee and fruit-derived beverages. QA determination therefore can be of interest in the quality control and authenticity testing of foods and beverages derived from fruits, beans and berries. Although QA levels should be expected to be quite commonly measured in vegetable and fruit extracts, this is rarely done. The reason for this lack of data on QA could be that this molecule is difficult to analyze in HPLC because of its high polarity, hydrophilicity and lack of chromophores [3-6].
In this study a simple HILIC-UV method was developed for the determination of QA using a ZIC-cHILIC 150x2.1mm, 3µm p.s. column at room temperature, with gradient elution using a pH 6.0 phosphate buffer and UV detection at 200nm. Validation of the method was carried out on cranberry juice. QA levels were measured in cranberry juice and in several other fruit juices, vegetable beverages, and fung
