Evaluating the Sustainability of Emerging Extraction Technologies for Chemical Analysis of Food Waste: Microwave, Ultrasound, Enzyme-Assisted, and Supercritical Fluid Extraction

The food industry generates substantial waste, raising economic and environmental concerns. Green Chemistry (GC) highlights extraction as key to waste valorization, driving interest in sustainable methods to recover valuable compounds efficiently. This review focuses on evaluating the sustainability of some of the most used emerging technologies, namely Microwave, Ultrasound, Enzyme-assisted, and Supercritical Fluid Extraction, and their compliance with GC principles. The review begins by exploring the principles, key parameters, and main advantages and disadvantages of each technique. Subsequently, the sustainability of these extraction techniques is evaluated in selected studies using the Analytical GREEnness Metric Approach (AGREEprep). By calculating the Greenness Score (GS), this metric assesses the adherence of extraction processes with sustainability standards. The analysis reveals variations within the same extraction technique, driven by factors such as the choice of solvents and operating conditions, as well as differences across the various extraction methods.