Abstract
Since the beginning of the 20th century, fruits and vegetables have historically been promoted as an important part of the human diet. The plethora of epidemiological and intervention studies has shown, since then, positive associations between fruit and vegetable intake and improved health outcomes and/or prevention of certain chronic diseases. In this regard, dietary fiber has traditionally been viewed as having beneficial effects due to inherent physical properties of solution viscosity and insoluble particles coupled with fermentation by colonic bacteria. However, it is now clear that they exert an important function as a carrier for phytonutrients, which is particularly important for fruits and vegetables, which often have high contents of bioactive phytonutrients such as polyphenols. Remarkably, production and processing of fruit and vegetables for human consumption results in a large amount of food waste due to their high-water contents, fast respiration rate, high sensitivity to environmental factors, and/or presence of inedible parts. Although the utilization of fruit and vegetable waste as animal feed is limited due to their low content of digestible energy, their rich palette of dietary fibers and polyphenols could make it a rich source of health-promoting dietary compounds. As an example, interest in the ability of dietary fibers and (poly)phenolic compounds to influence carbohydrate metabolism and colonic health could make problematical fruit and vegetable biomass a game-changer source of dietary supplements. This presentation will cover recent progress on the nature of interactions between polyphenols and the plant cell wall, how this affects polyphenol bioaccessibility and bioavailability during digestion, and how processing can result in dietary supplements with tailored structure and solubility of their dietary fibers and chemical stability and bioaccesibility of their (poly)phenolic compounds.
Dietary fibers from fruit and vegetable waste: methods of extraction and processes of value addition