Preparation and Characterization of an Immobilized Enological Pectinase on Agar‐Alginate Beads

Abstract

AbstractA commercial enological pectinase is immobilized on agar‐sodium alginate hydrogel beads via external gelation technique. Biocatalyst surface and their internal morphology are characterized by Scanning Electron Microscopy and a good enzyme distribution throughout mixt biopolymer matrix is observed. The biocatalyst is characterized by Fourier Transform Infrared Spectroscopy, confirming the presence of absorption bands associated with amino groups present in the enzyme. Mechanical performance of beads is followed by Texture Profile Analysis and it is demonstrated that agar‐alginate beads exhibited a hardness 3.8 times higher than agar beads. Enzymatic activity of the immobilized pectinase prepared under the optimal conditions reached 0.592 ± 0.041 U per grams of beads. Reusability studies indicated that the immobilized pectinase retained 61% of its initial activity after six successive cycles. The use of the developed biocatalyst decreased significantly the turbidity values after grape must is treated for 120 min at 20 °C. Due to these good properties, the immobilized pectinase synthetized in this work may find applications in the clarification process of winemaking.