Assessment of traditional clarifiers on the adsorption of ochratoxin A in Cabernet Sauvignon red wine and their kinetics

Abstract

The effect of clarification on the elimination of Ochratoxin A (OTA) in wine was studied and the adsorption behavior of different clarifiers was evaluated. The results showed that OTA in wine can be effectively eliminated by gelatin with an adsorption rate of 28.59%, followed by chitosan (24.7%), bentonite (22.5%) and polyvinylpyrrolidone (PVPP) (7.6%). The clarification process was significantly affected by the clarifiers and OTA concentration. In addition, the experimental kinetic data for OTA removal were also evaluated by different equations. It displayed that the adsorption of gelatin and PVPP can be simulated by Pseudo-first order equation and Elovich equation, while that of chitosan and bentonite followed Pseudo-second order equation. The adsorption behavior of gelatin, chitosan and bentonite can fit Freundlich equation, Temkin equation and Dubinin-Radushkevich, and that of PVPP can only fitted by Langmuir equation. The thermodynamic parameters further revealed that the adsorption of OTA in wine was non-spontaneous.

Keywords: Adsorption; Adsorption isotherm; Clarifiers; Kinetic model; Ochratoxin A; Wine.