Natural antioxidants have attracted attention owing to their potential good effects in health. On the other hand, valorization of residues is an opportunity to obtain profit in a sustainable way. In this work antioxidants were obtained from residues of rosemary after extraction of essential oil using steam distillation, hydrodistillation and Solvent Free Microwave Extraction (SFME). A solvent extraction with ethanol was used to obtain the antioxidants. Then a comparison of the results is made in order to know which process delivers a residue with higher concentration of antioxidants. Mass transfer rates of antioxidants from leaves are increased as a result of the previous extraction of essential oils. Higher yields and rates of extract from leaves after SFME have been observed.
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