Unlocking the green potential: sustainable extraction of bioactives from orange peel waste for environmental and health benefits

Oranges dominate the world in terms of harvested area, with an annual global production of 60 million tonnes. Approximately 40–50% of orange production is utilized for fruit processing. Notably, the peel waste generated from juice processing industries exceeds 32 million tonnes. Most of the waste generated is either disposed of in landfills or thrown into rivers, leading to water contamination and elevated pollution rates. Factors contributing to this include low pH, high water and organic content, ease of fermentability, and substantial demand for oxygen. The orange peel is rich in bioactives, providing protection against a range of diseases. Both traditional and non-conventional extraction methods, are available to extract these bioactives. Traditional methods come with various limitations, meanwhile, the non-conventional green extraction methods like microwave assisted extraction (MAE), supercritical fluid extraction (SFE), ultrasound assisted extraction (UAE), pulse electric field extraction (PEF), enzyme-assisted extraction (EAE), etc., are becoming more significant because of their no thermal nature and environmentally beneficial characteristics. Moreover, green extraction methods employ reduced amounts of solvents, consume less energy, require shorter extraction time, yield higher extraction rate, and are environmentally friendly. This review compiles the effective utilization of orange peel for the bioactive recovery, sources, properties and novel extraction techniques.