Improved lycopene extraction from tomato peels using cell-wall degrading enzymes

Four commercial enzyme preparations with pectinolytic, cellulolytic and hemicellulolytic activities were tested for their ability to enhance lycopene extraction from tomato peels. Screening experiments were performed at 25 °C by subjecting the peels to a 4-h enzyme incubation followed by 1-h hexane extraction. Peclyve EP and LI were the most efficient, with an almost 20-fold increase in extraction yield. Peclyve LI was used to evaluate the influence of solvent type and enzyme incubation time on lycopene recovery. Hexane, ethyl acetate and the mixture hexane/acetone/ethanol 50:25:25 (v/v) were used as solvents. Under the best extraction conditions (1-h enzyme incubation followed by a 3-h solvent extraction at 40 °C) up to 440 mg of lycopene per 100 g of dry tomato peels were obtained. The percentage recoveries were in the range of 3–30%, for the untreated peels, and 77–98% for the enzymatically treated material.