Use of a solution of organic acids, a byproduct of the Rectified Concentrated Must production process, for the acidification of wines

¹ CREA – Consiglio per la Ricerca in Agricoltura e l'Analisi dell'Economia Agraria – Centro di Ricerca Viticoltura ed Enologia, Via P. Micca 35, Asti, Italy
² Naturalia Ingredients S.r.l. – Gruppo Industriale Maccaferri, Via Avv. Ballatore 5, Mazara del Vallo (TP), Italy

Abstract

The production cycle of Rectified Concentrated Must (RCM) includes a deionization phase performed with ion exchange resins, that are regenerated after each deionization cycle with strong mineral acids or strong bases. The resulting waste water is particularly rich in cations and anions removed from the must, and various processes for the recovery of tartaric acid are normally performed. More recently, new techniques have been developed for the recovery of all organic acids of the must as concentrated solutions of organic acids (SGA: Solutions of Grapes organic Acids). The work was aimed at determining the acidic profile and some specifics of SGA for a possible use as wine acidifiers. Moreover, some trials were carried out to define the correct dose of SGA to be added to wines in order to cause a given decrease of pH, equivalent to that obtained with H₂T. As a result, a method was proposed for the calculation of the dose of SGA needed to determine a given decrease of wine pH. The recovery and valorization of SGA from the RCM processing cycle can represent a virtuous example of biorefinery, within the framework of the circular and green economy promoted by EU.