Immobilization of enological pectinase by absorption on polyamide 6 microparticles and its application in the clarification of wine must

• Author(s): Oliveira, Sandra Cristina Gomes ; Dencheva, Nadya Vasileva ; Denchev, Z.
• Date: 2024
• Persistent ID: https://hdl.handle.net/1822/94168
• Origin: RepositóriUM - Universidade do Minho
• Document Type: Conference poster
• Language: English
• Contributor(s): Universidade do Minho

Description

Introduction: Enzymes are widely used as efficient biocatalysts in the food industry for various purposes. In winemaking, a specialized sector where enzymes play a crucial role, pectinases occupy a central position. These enzymes significantly influence the sensory properties of wines by catalyzing the hydrolysis of pectin, responsible for wine cloudiness. This contributes to enhancing clarification and filtration processes without compromising valuable wine components. However, native enzymes are very sensitive to extreme conditions, e.g., pH and temperature, and cannot be re-used. To overcome these limitations, enzymes can be immobilized on polymer supports. Polyamides could be good supports because they are biocompatible and possess appropriate physical and chemical properties that allow covalent and not-covalent enzyme immobilization. Objectives: Immobilization of a commercial pectinolytic preparation on highly porous polyamide 6 microparticles (MPA6), with and without magnetic properties; Application of the new complexes for the clarification process of industrial rosé must. Results: MPA6 with and without magnetic properties, were synthesized with controlled shape, size, and porosity by activated anionic ring-opening polymerization of caprolactam in solution. The pectinase immobilization was performed at room temperature, 24 hours, at pH 4.5. The activity of the new complexes against pectin was determined, as well as their kinetic parameters. In comparison with the free enzyme, the PA6-immobilized pectinase displayed a slightly higher affinity to the substrate pectin while acting as faster catalysts, being more resistant to inhibition. Furthermore, the immobilized complexes were applied in the clarification process of industrial rosé must samples and demonstrated enhanced performance, as compared to the free enzyme. Additionally, the immobilized pectinase biocatalysts offered the potential for 3 consecutive cycles of reuse. Conclusion: The developed PA6-pectinase complexes exhibited enhanced activity compared to the unbound enzyme. Kinetic investigations revealed a slight increase in their affinity towards the pectin substrate resulting in higher maximum velocities of pectin hydrolysis. In terms of clarification, these complexes demonstrated a slight acceleration in the process compared to the free enzyme, and they also proved capable of enduring multiple consecutive cycles of use.