Commercially suitable pectin methylesterase from Valencia orange peels

Authors : Şebnem ŞİMŞEK, Ahmet YEMENİCİOĞLU

Pages : 109-119

View : 25 | Download : 17

Publication Date : 2010-04-01

Article Type : Research Paper

Abstract :A simple and effective procedure was developed to extract pectin methylesterase insert ignore into journalissuearticles values(PME); from Valencia orange peels. Orange peels contain 25-34 mmol of COOH min-1 g-1 of peel PME activity. The enzyme was ionically bound to cell walls and could not be extracted with water. This enables removal of water soluble pectic substances and oils from peels via homogenization and washing with water before enzyme extraction. Enzyme extraction can be conducted simply by addition of suitable amounts of NaCl insert ignore into journalissuearticles values(optimum: 10 g of NaCl 100 g-1 of extraction mixture); to peel homogenate and stirring insert ignore into journalissuearticles values(optimum: 30 min at 200 rpm);. The PME extracted from orange peels contains almost the same amount of heat-stable and heat-labile fraction, and the enzymes cannot be activated by mild heating. A slight activation of enzyme insert ignore into journalissuearticles values(almost 20%); was achieved by adding 1 mM CaCl2 to enzyme extracts, but this agent was inhibitory at higher concentrations. The extracts stabilized by Na-benzoate and K-sorbate maintained more than 90% of their PME activity at 4 °C for at least 5 months. The obtained PME was successfully used to prepare low-methoxyl citrus pectin used in edible film formation in the presence of CaCl2. This study shows the potential of using Valencia orange peels as a source of commercial PME.
Keywords : Key words Extraction, orange peel, pectin methylesterase, stability, Valencia orange