Organic Acids, Sugars, and Glycerol Content in White Winemaking Products Determined by HPLC: Relationship to Climate and Varietal Factors

Abstract

An ion-exclusion polymeric HPLC method with RI detection was developed for direct separation and quantitation of organic acids (citric, tartaric, malic, succinic, galacturonic, and lactic), sugars (glucose and fructose), and glycerol in white winemaking products. The precision, linearity, sensitivity, and accuracy of the method were satisfactory. This rapid method — without sample preparation — was applied to routine quality control procedures in the winemaking industry: 33 A.O.C. Penedès varietal musts (Macabeo, Xarel.lo, and Parellada) and their white wines from five harvests (1989-1993) were analyzed. The contents of some of these compounds were related to grape variety (galacturonic acid) and/or climate parameters (citric, malic and galacturonic acids, and glycerol). Macabeo wines have high amounts of galacturonic acid than other varietal wines. The must content of malic and citric acids were correlated with weather factors such as temperature, atmospheric pressure, and rain; galacturonic acid and glycerol levels in must were affected by humidity.