Polyphenol content in fruits usually refers to extractable polyphenols, but a Spanish scientist working at the Institute of Food Research in Norwich analysed apple, peach and nectarine. She found that nonextractable polyphenol content is up to five times higher than extractable compounds. Its really interesting and that might be the reason why our forefathers used to insist to eat whole fruits (though they might not have studied so exhaustively... !).
The interesting findings like, "polyphenols need to be treated with acid to extract them from the cell walls of fruit in the lab" will help at least now onwards to collect all the useful polyphenols (proanthocyanidins, ellagic acid and catechin) which without this new findings might have gone as waste. Dr Paul Kroon from IFR explains: “In the human body these compounds will be fermented by bacteria in the colon, creating metabolites that may be beneficial, for example with antioxidant activity.
Hope these nonextractable polyphenols, (which mostly escape analysis and are not usually considered in nutritional studies), will play a major part of bioactive compounds in the diet in the days to come. Congrats Professor Saura-Calixto, for this achievement.....
