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Inhibition of apricot polyphenol oxidase by combinations of plant proteases and ascorbic acid.

ABSTRACT: The present research investigates the long term inhibition of enzymatic browning by inactivating the polyphenol oxidase (PPO) of apricot, using combinations of plant proteases and ascorbic acid (AA). The selected proteases were able to inactivate PPO at pH 4.5, with the degree of inactivation proportional to incubation time and protease concentration. Papain was the most effective protease, with 50??g completely inactivating PPO in less than one hour. AA prevented browning reactions that occur before or during PPO inactivation by protease. The combinations of AA/proteases were highly effective in vitro, where 2?mM AA/500??g proteases inhibited PPO activity completely over 24?h. The combination of AA/proteases was also effective in vivo, as treated apricot purees preserved their color (p?

SUBMITTER: Derardja AE

PROVIDER: S-EPMC6804514 | biostudies-literature | 2019 Dec

REPOSITORIES: biostudies-literature

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Inhibition of apricot polyphenol oxidase by combinations of plant proteases and ascorbic acid.

Derardja Ala Eddine AE Pretzler Matthias M Kampatsikas Ioannis I Barkat Malika M Rompel Annette A

Food chemistry: X 20190911

The present research investigates the long term inhibition of enzymatic browning by inactivating the polyphenol oxidase (PPO) of apricot, using combinations of plant proteases and ascorbic acid (AA). The selected proteases were able to inactivate PPO at pH 4.5, with the degree of inactivation proportional to incubation time and protease concentration. Papain was the most effective protease, with 50 μg completely inactivating PPO in less than one hour. AA prevented browning reactions that occur b ...[more]

PMID: 31650127

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