Pectic principles of mango peel from mango processing waste as influenced by microwave energy

- Microwave extraction of mango peel yielded maximum pectin within a short time period of 20 min.
- Pectin with high degree of esterification could be obtained at microwave energies of 660 and 1000 W for 20 min.
- Maximum pectin yield was observed at microwave energy of 1000 W for 20 min.
- Pectin of good quality can be extracted from mango peel using microwave energy.

Mango var. Totapuri is extensively processed into mango puree by the fruit processing industries. It results in generation of huge quantities of processing waste comprising of mango peel, stone and fibre. Microwave energy levels of 250, 440, 660 and 1000 W with time period ranging from 10 min to 25 min were studied for pectin extraction from mango peel. Microwave extraction affected the yield, methoxyl content, galacturonic acid and viscosity of pectin. Maximum pectin yield could be obtained with a short heating period as compared to the conventional method of extractions reported earlier. Higher methoxyl content and viscosity were observed in the mango peel pectin extracted at 660 and 1000 W for 20 min indicating the better gelling properties of the pectin. Yield of pectin was found to be maximum from the mango peel exposed at microwave energy of 1000 W for 20 min. Methoxyl content, viscosity, galacturonic acid decreased at 25 min of extraction at all microwave energy levels studied. Pectin extracted at the optimum conditions contained galacturonic acid, methoxyl content and viscosity of 57.2 g/100 g, 8.2 g/100 g and 98.2 mPa s respectively. Microwave extraction of mango peel under selected conditions resulted in higher yield of pectin.