Enzymatic peeling of apricots, nectarines and peaches

Different combinations of Peelzym (I, II, III and IV) concentration (0.1, 0.55, 1 cm(3) enzyme/100 cm(3) solution), temperature (20degreesC, 35degreesC, 50degreesC), pH (3.0, 4.5, 6.0) and time (20, 40, 60 min) were used for enzymatic peeling of apricots, nectarines and peaches. The optimum conditions were determined by using response surface methodology. Peeling yield, absorption of enzyme solution and texture changes were measured after peeling. For peeling of apricots with Peelzym IV, the optimum temperature was 45degreesC; the optimum values of time were in the range of 57-60 min and that of pH and enzyme concentration were in the ranges of 3-3.5 and 0.85-0.90 cm(3) enzyme/100 cm(3) solution, respectively. Optimum conditions of peeling for nectarines were determined to be temperature, 44-47degreesC; time, 53-58 min; pH, 3.5-4.1; and enzyme concentration, 0.70-0.90 cm(3) enzyme/100 cm(3) solution by using Peelzym I. For peaches the ranges were 41-46degreesC for temperature, 44-54 min for time, 3.6-4.5 for pH and 0.73-0.90 cm(3) enzyme/100 cm(3) solution by using Peelzym IV. By this method, peeling was successful at moderately high temperatures. (C) 2003 Swiss Society of Food Science and Technology. Published by Elsevier Science Ltd. All rights reserved.