R.U.1 - ALMA MATER STUDIORUM - UNIVERSITY OF BOLOGNA

RU1 will mainly be involved in the first phase of the project. The activities will focus on various tests using environmentally friendly solvent mixtures and sustainable technologies to select the best procedure for the optimal extraction of functional phenolic compounds still present in apple pomace, in order to transform this common agri-food waste into a safe, high-quality extract/product enriched with value-added molecules. Natural Deep Eutectic Solvents (NADES) will be used as the solvents of choice. These are environmentally friendly solvents characterized by high solvent power, low toxicity, and high biodegradability.

The extraction efficiency will be measured in terms of the type and concentration of the various classes of phenolic compounds found in the skin and other parts of the pomace: anthocyanins, hydroxycinnamic acids, flavonoids, type B procyanidins, flavonols, and flavan-3-ol monomers. It will also measure antioxidant capacity in vitro using various spectrophotometric assays. The extraction optimization process will follow a Response Surface Methodology (RSM) approach, a statistical method that allows the evaluation of the interaction effects between the different variables used and their optimization. Once the optimal extraction technique has been selected in terms of extraction time and temperature and solid-liquid ratio, it will be applied to samples of peel and pomace taken from different cultivars, which differ in the intensity of the red color of the fruit peel (Red Moon, Red Love, Polpa Rossa Unibo, Mela Rosata Unibo). These activities are complemented by the unit's researchers' many years of experience.

Following the results obtained by RU2, RU1 will be involved in the bio-guided fractionation process and chemical characterization of the extracts that prove most promising in terms of biological properties.