Premium
Comparative Study of the Inactivation Kinetics of Pectinmethylesterase in Tomato Juice and Purified Form
Author(s) -
Fachin Diana,
Van Loey Ann M.,
Nguyen Binh Ly,
Verlent Isabel,
Hendrickx Marc E.
Publication year - 2002
Publication title -
biotechnology progress
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.572
H-Index - 129
eISSN - 1520-6033
pISSN - 8756-7938
DOI - 10.1021/bp0155080
Subject(s) - chemistry , pectinesterase , isoelectric point , chromatography , kinetics , thermal stability , pectinase , food science , enzyme , biochemistry , organic chemistry , physics , quantum mechanics
Pectinmethylesterase (PME) extracted from tomato fruit was purified by affinity chromatography. A single peak of PME activity was observed, presenting a molar mass of 33.6 kDa, an isoelectric point higher than 9.3, and an optimal temperature and pH for activity of 55 °C and 8.0, respectively. The processing stability of purified tomato PME in buffer solution was compared to PME stability in tomato juice. In both media, thermal inactivation of PME presented first‐order inactivation kinetics, PME in tomato juice being more heat‐labile than purified PME. Regarding high‐pressure treatment, tomato PME showed to be very pressure‐resistant, revealing an outspoken antagonistic effect of temperature and pressure. To avoid cloud loss in tomato juice, a time‐temperature treatment of 1 min at 76.5 °C was calculated in order to have a residual PME activity of 1 × 10 −4 U/mL.