Pulsed ultrasound assisted extraction of protein from defatted Bitter melon seeds (Momardica charantia L.) meal: Kinetics and quality measurements
Mohan Naik, Venkatachalapathy Natarajan, Nikitha Modupalli, Suka Thangaraj, Ashish Rawson
Abstract
Bitter melon seeds (BMS) are a one such by-product discarded from Bitter gourd processing industries. In this study our aim was extraction of protein from defatted Bitter melon seeds meal using pulsed ultrasound assisted extraction (PUSAE). Effect of ultrasound power level (300, 375 and 450W) and time (2.50, 5.00, 7.50, 10.00, 12.50, 15.00, 17.50 and 20.0 min) on protein yield and quality characteristics were evaluated. Peleg's model was used to describe the kinetics of extraction process. The highest yield of 23.79% at 300W, 31.05% at 375W and 28.93% at 450W was obtained. At a higher ultrasound power levels, the yield was slightly reduced due to protein aggregation formation. Enhancement in water holding capacity, solubility, emulsion capacity, emulsion stability and least gelation capacity in PUSAE protein samples were observed compared to conventional extracted Bitter melon seed protein. The FTIR absorption spectra reveal the characteristics changes in secondary structure of protein mainly in the region of α-helix, β-sheet, β-turn and random coil. The present study indicates that PUSAE increases the protein yield and improves the techno-functional characteristics of Bitter melon seed protein.