In this article:

The influence of oxygen on the reaction of polyphenoloxidase in grapes was determined. Rapid browning of injured fresh fruits, fruit juices and drying fruits is generally caused by polyphenoloxidases.

The importance of these results for wine making is discussed

The Affinity for Oxygen of Polyphenoloxidase in Grapes

1973, Zeitschrift für Lebensmittel-Untersuchung und -Forschung., vol 152, pages 38 – 41

csiro 290

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