Popis: |
Publisher Summary Polar antioxidants work better in non-polar matrices and non-polar antioxidants work better in polar matrices—hence, the “Polar paradox”. This pattern has provided a useful framework for further thought and experimentation about the function of antioxidants. William Porter's simple enunciation of the polar paradox should receive some credit for the amazing progress that has been made in the understanding of oxidation and antioxidants over the past 30 years, as it provided a framework within which questions could be asked, experimentally probed, and answered. This chapter explores such questions, experiments, and hypotheses. The polar paradox will be problematic if a generalized explanation is expected to fit all situations. Recent efforts have tried to explain the relationship between polarity and antioxidant behavior, especially in emulsions. These efforts to better understand the effect of minor oil components and various emulsion constituents and to utilize new series of antioxidants have led to better explanations of paradoxical behavior in system models. However, it remains difficult to predict antioxidant performance and behavior without considering the effect of many other factors, such as nature and amount of pro-oxidants, functionality of antioxidants, and the emulsion. The value of the polar paradox lies not in its ability to explain antioxidant performance but in the questions that it generates in the minds of researchers as they seek to explain the complex phenomenon of oxidation in foods. |