title: Immobilization of tomato (Lycopersicon esculentum) pectinmethylesterase in calcium alginate beads and its application in fruit juice clarification.
abstract: Clarity of fruit juices is desirable to maintain an aesthetically pleasing quality and international standards. The most commonly used enzymes in juice industries are pectinases. A partially-purified pectinmethylesterase from tomato was entrapped in calcium alginate beads and used for juice clarification. The activity yield was maximum at 1 % (w/v) CaCl2 and 2.5 % (w/v) alginate. The immobilized enzyme retained ~55 % of its initial activity (5.7 × 10(-2) units) after more than ten successive batch reactions. The Km, pH and temperature optima were increased after immobilization. The most effective clarification of fruit juice (%T620 ~60 %) by the immobilized enzyme was at 4 °C with a holding time of 20 min. The viscosity dropped by 56 % and the filterability increased by 260 %. The juice remains clear after 2 months of storage at 4 °C.
authors.affiliation: Department of Biotechnology, Seth Jai Parkash Mukand Lal Institute of Engineering and Technology (JMIT), Radaur, Yamuna Nagar, 135133, Haryana, India, poonam2073@yahoo.co.in.
authors.forename: Pushpa
authors.initials: P
authors.lastname: Bogra
authors.forename: Ashwani
authors.initials: A
authors.lastname: Kumar
authors.forename: Kalika
authors.initials: K
authors.lastname: Kuhar
authors.forename: Surbhi
authors.initials: S
authors.lastname: Panwar
authors.forename: Randhir
authors.initials: R
authors.lastname: Singh
mesh_terms: D000464:Alginates / Q000737:chemistry*; D001628:Beverages; D002265:Carboxylic Ester Hydrolases / Q000737:chemistry / Q000378:metabolism*; D004795:Enzyme Stability; D004800:Enzymes, Immobilized / Q000737:chemistry / Q000378:metabolism*; D005511:Food Handling / Q000379:methods*; D020723:Glucuronic Acid / Q000737:chemistry; D006603:Hexuronic Acids / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D018551:Solanum lycopersicum / Q000201:enzymology*; D008863:Microspheres; D013696:Temperature
chemical_list: D000464:Alginates; D004800:Enzymes, Immobilized; D006603:Hexuronic Acids; D020723:Glucuronic Acid; D002265:Carboxylic Ester Hydrolases; C022323:pectinesterase