Electro-biorefinery as a Potential Tool for Valorization of Mango and Papaya By-products

摘要

During exotic fruits processing, a large amount of by-products, especially seeds and peels, are produced and discarded into the environment causing organic pollution. However, it is recognized that these by-products are a good source of high-added value compounds, which can be used for different purposes (i.e. food additives and/or nutraceuticals). At this stage of development, there is a lack of information about the different extraction methods that can be used for the recovery of high-added value compounds from papaya and mango by-products. In this line, the extraction assisted by pulsed electric technologies seems to be rather promising. In this research study, the exponential decay pulses with initial electric field strengths of =13.3 kV/cm and =40 kV/cm for PEF and HVED treatments, respectively, were used. The impacts of temperature and pH on extraction efficiency of different components (proteins, total phenolic compounds, carbohydrates, isothiocyanates) and antioxidant capacity were evaluated. The highest values of nutritionally valuable and antioxidant compounds were obtained for HVED-assisted extraction. However, the application of HVED-treatment may produce undesirable contaminants (chemical products of electrolysis, free reactive radicals, etc.) and the obtained extracts were unstable and cloudy. Application of the two-stage method (PEF + supplementary aqueous extraction at 50 °C) allowed a significant enhancement of the yields (=+200%) and antioxidant capacities (=+20%) of the extracted components from papaya and mango by-products even at neutral pH.