Mild-Heat and High-Pressure Inactivation of Carrot Pectin Methylesterase: A Kinetic Study

• Published in: Journal of food science Vol. 68; no. 4; pp. 1377 - 1383
• Main Authors: Ly-Nguyen, B, Loey, A.M. Van, Smout, C, ErenÖzcan, S, Fachin, D, Verlent, I, Vu Truong, S, Duvetter, T, Hendrickx, M.E
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Publishing Ltd 01.05.2003; Institute of Food Technologists; Wiley Subscription Services, Inc
• Subjects: affinity chromatography; Analytical, structural and metabolic biochemistry; Biological and medical sciences; carrots; Chromatography; Enzymes and enzyme inhibitors; Food industries; Food science; Fruit and vegetable industries; Fundamental and applied biological sciences. Psychology; heat; heat inactivation; high pressure; Hydrolases; inactivation; Kinetics; mathematical models; pectin methylesterase; pectinesterase; temperature; Heat treatment; Carrot; Vegetables; Physical dressing; Enzyme; Esterases; fractivation; Inactivation; Carboxylic ester hydrolases; High pressure; Heating; pectin methylesterase; Hydrolases; carrots; Kinetics; Pectinesterase
• ISSN: 0022-1147; 1750-3841
• DOI: 10.1111/j.1365-2621.2003.tb09653.x

Pectin methylesterase (PME) was extracted from carrots and purified by affinity chromatography. The thermal high-pressure inactivation of the PME was investigated in a model system. Under these conditions, the (thermo) stable fraction is not inactivated and the isobaric-isothermal inactivation followed a fractional-conversion model. At lower pressures (< 300 MPa) and higher temperatures (> 50°C), an antagonistic effect of pressure and heat was observed. A 2nd- and 3rd-degree polynomial model (derived from available thermodynamic model) was successfully used to describe the heat pressure dependence of the inactivation rate constants. From the purified carrot PME sample, the thermostable PME fraction was isolated. The thermal inactivation of this fraction followed first-order kinetics.