Premium
Catechol oxidases, endogenous substrates and browning in developing apples
Author(s) -
Harel E.,
Mayer A. M.,
Shain Y.
Publication year - 1966
Publication title -
journal of the science of food and agriculture
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.782
H-Index - 142
eISSN - 1097-0010
pISSN - 0022-5142
DOI - 10.1002/jsfa.2740170901
Subject(s) - browning , catechol , chemistry , polyphenol oxidase , food science , catechol oxidase , substrate (aquarium) , enzyme , horticulture , biochemistry , botany , biology , peroxidase , ecology
The content of o ‐diphenols and catechol oxidase activity was followed in developing apples from fruit set to harvest time. Afterwards their level drops, apparently due to conversion to other compounds and cessation of synthesis. Catechol oxidase activity shows a peak after that occurring in content of o ‐diphenols. As the fruit ripens, activity drops sharply in the particulate fractions. In the ripe apple a slight amount of soluble enzyme appears. These findings were correlated with the rate of browning of apple slices and the location of enzymes and their substrate in the fruit. Browning of slices could be prevented by dipping them into solutions of I m M ‐2,3‐naphthalenediol or 2·5% N ‐vinyl‐2‐pyrrolidone. Addition of 1 m M ‐sodium ascorbate to the dipping medium improved the efficiency of prevention of browning.