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Updated: May 13, 2026
10:14
Expression and Purification of Nuclease-Free Oxygen Scavenger Protocatechuate 3,4-Dioxygenase
Published on: November 8, 2019
Triggering mechanisms for oxygen-scavenging function of ascorbic acid-incorporated whey protein isolate films
Theeranun Janjarasskul1, Sea C Min, John M Krochta
1Department of Food Science and Technology, University of California, Davis, CA 95616, USA.
Journal of the Science of Food and Agriculture
|March 2, 2013
Summary
Ascorbic acid (AA) in whey protein isolate (WPI) films effectively scavenges oxygen, with high water activity and neutral pH accelerating this protective function for food oxidation.
Area of Science:
- Food Science
- Material Science
- Biochemistry
Background:
- Whey protein isolate (WPI) films incorporated with ascorbic acid (AA) enhance food protection against oxidation.
- The oxygen (O₂) scavenging capability of AA-WPI films can be activated by contact with food products.
- Investigated food factors include water activity (a(w)), pH, and metal catalysts as triggers for O₂ scavenging.
Purpose of the Study:
- To investigate the triggering mechanisms for activating the O₂-scavenging function of AA-WPI films.
- To determine the influence of food-related factors on the O₂-scavenging rate of AA-WPI films.
Main Methods:
- Studied the kinetics of O₂ scavenging by AA-WPI films.
- Evaluated the effect of varying water activity (a(w)) levels on O₂ scavenging rates.
- Assessed the impact of different pH values and the presence of Cu²⁺ on O₂ scavenging.
Main Results:
- O₂ scavenging by AA-WPI films followed first-order kinetics.
- Film water activity (a(w)) was identified as the primary controller of the O₂-scavenging rate.
- Optimal O₂ scavenging occurred at high a(w) and neutral pH (7.4), with Cu²⁺ further accelerating the process at high a(w).
Conclusions:
- AA-WPI films demonstrate effective oxygen scavenging activation under conditions of high a(w), neutral pH, and in the presence of metal catalysts.
- These findings suggest AA-WPI films are suitable for protecting foods highly susceptible to oxidation.
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