Efficient immobilization of a fungal laccase and its exploitation in fruit juice clarification

卷:196

Lettera, Vincenzo ; Pezzella, Cinzia ; Cicatiello, Paola ; Piscitelli, Alessandra ; Giacobelli, Valerio Guido ; Galano, Eugenio ; Amoresano, Angela ; Sannia, Giovanni

Univ Naples Federico II

关键词: Response Surface Methodology;    Phenols;    Laccase immobilization;    Food industry;    Mass spectrometry analysis;   

DOI  :  10.1016/j.foodchem.2015.10.074

学科分类：食品科学和技术

【 摘 要 】

The clarification step represents, in fruit juices industries, a bottleneck process because residual phenols cause severe haze formation affecting juice quality and impairing customers acceptance. An enzymatic step can be efficiently integrated in the process, and use of immobilized enzymes entails an economical advantage. In this work, covalent immobilization of recombinant PDXA1b laccase from Pleurotus ostreatus on epoxy activated poly(methacrylate) beads was optimized thanks to a Response Surface Methodologies approach. Through regression analysis the process was well fitted by a quadratic polynomial equation (R-2 = 0.9367, adjusted R-2 = 0.8226) under which laccase activity reached 2000 +/- 100 U g(-1) of beads, with an immobilization efficiency of 98%. The immobilized biocatalyst was characterized and then tested in fruit juice clarification reaching up to 45% phenol reduction, without affecting health-effective flavanones content. Furthermore, laccase treated juice displays an improved sensory profile, due to the reduction of vinyl guaiacol, a potent off-flavor possessing a peppery/spicy aroma. (C) 2015 Elsevier Ltd. All rights reserved.