Thanks, Michal, for your kind appreciation and for providing the link. I had the study in my library already, because I had to investigate the effects of banana PPO on the smoothie. These effects are to be considered, particularly in food preparations that are not consumed immediately. However, when exposure is brief (consuming the blended items directly after preparation), then the polyphenol loss shouldn't be of great concern. Another question that complicates the interpretation is that most polyphenols aren't easily absorbed intact. That is, they probably unfold their health effects through the various metabolites to which they are transformed by the gut microbiota. Hence the view on PPO's degrading effect on polyphenols may be too narrow.