Effect of pectinase on volatile and functional bioactive compounds in the flesh and placenta of ‘Sunlady’ cantaloupe

The effect of commercial pectinase, Pectinex^® Ultra SP-L (10,292 PGU/ml), on volatile and functional bioactive compounds of flesh and placenta of fully ripe cantaloupe cv. Sunlady was studied. It was found that enzymatic degradation of cantaloupe flesh and placenta until the reducing sugar contents as 57.09-58.48 and 39.12-40.44 mg glucose/g FM, respectively, had more bioactive compounds than other conditions significantly (p≤0.05). Antioxidant activities of flesh and placenta detected by DPPH method were 9 and 4 times higher than the undegraded samples (control) (1.57, 0.66 μg FM/μg DPPH); and those measured by ABTS method were 3 and 2 times higher than undegraded samples (5.12, 7.88 μg Trolox equivalents/g FM). Total phenolic contents were 8 and 3 times higher than the undegraded samples (14.95, 39.72 mg gallic acid equivalents/100 g FM). Total flavonoid contents were 10 and 2 times higher than the undegraded samples (2.25, 12.24 mg catechin equivalents/100 g FM). Beta-carotene had increased from 68.15 to 76.71 μg/100 g FM in flesh and 97.23 to 181.89 μg/100 g FM in placenta. Dietary fiber changed from 0.65 to 0.76 g/100 g FM in flesh and 0.32 to 0.52 g/100 g FM in placenta. Prebiotic activities resulted from probiotic type L.acidophilus La5 in flesh and placenta were 0.15 and 0.14, respectively, and ones from B.lactis Bb12 were 0.34 and 0.33, respectively.. Furthermore, the main volatile compounds found in enzymatic degraded flesh were nonanal, cis-6-nonen-1-ol, and geranyl acetone as well as those found in placenta were ethyl acetate, nonanal, cis-3-nonen-1-ol, and cis-6-nonen-1-ol, etc. Therefore, fully ripe cantaloupe flesh and placenta extracted by enzyme can be a good material to be developed as food colorant with bioactive compound and to be used instead of synthetic agent in the future.