Zero waste principle for the fruit processing industry: Recovery, advanced conversion and revalorization approaches

The fruit processing industry holds a significant position in the global economy; however, it also has substantial environmental impacts. The fruit processing industry generates significant amounts of waste, accounting for up to 8 % of total food waste. The water footprint of this industry is concerning, with approximately 10 L of wastewater generated for every 1 L of juice produced. These abundant, inexpensive, and easily accessible waste materials contain high amounts of beneficial compounds that can serve as substrates for biochemical transformations. These waste streams are rich in valuable phytochemicals, particularly phenolic compounds, which possess antioxidant, antimicrobial, and antiviral properties. Phytochemicals can be utilized in the food industry, healthcare, pharmaceutical industry, and cosmetics. In this way, negative effects on the environment, the pollution load of wastewater, and economic losses can be reduced, contributing to the circular economy. However, the wastewater still requires treatment even after some compounds have been recovered. Treatment plants generally include biological processes, while some technologies, such as membrane-based systems and advanced oxidation, have also been reported in the literature. This study aims to reveal the recovery, advanced conversion, and revalorization approaches of valuable components from fruit processing industry wastes for sustainable and environmentally friendly food production by reviewing the current literature.