Reuse of Food Waste and Wastewater as a Source of Polyphenolic Compounds to Use as Food Additives

The problem of waste and byproducts generated from agro-industrial activities worldwide is an increasing concern in terms of environmental sustainability. In this ambit, the quantity of food wastes—produced in all steps of the whole food chain— is enormous, and it may be forecasted that food waste could amount to more than 120 billion tonnes by 2020. The reuse of food waste and wastewater as source of polyphenolic compounds could be an interesting discussion in this ambit. In fact, polyphenols obtained in this way might be used for food and non-food purposes by means of new, improved, and safe extraction methods. In light of the opportunity represented by the treatment of agro-industrial waste, different systems concerning the winemaking and olive oil production industries have also been discussed as describing approaches applicable to other sectors. More research is needed before considering recovery of phenolic compounds from wastewater as an economically convenient choice for the food sector.