Characterization and functional properties of muskmelon seed meal and oil

Abstract

Muskmelon seeds, often discarded as waste, are rich sources of protein and healthy oil, making them excellent alternate sources of fat and protein. Muskmelon seeds of hybrid cultivars were assessed for their physico-chemical and functional properties. Fat and protein content of endosperm varied from 38.77–42.74 % and 22.6–35.17 %, respectively. Muskmelon seed oil showed desired characteristics as per WHO norms with high saponification value of 190.28–197.65. Linoleic acid (60.5–65.6 %) and palmitic acid (8.3–9.5 %) were the major constituent of melon seed oil. Defatted muskmelon seed meals (DSMs) contained 36.45–48.12 % proteins and minerals like potassium, phosphorous, magnesium and calcium. The total polyphenol content of the various DSMs ranged from 11.94 to 15.503 mg GAE/g, and the antioxidant activity quantified as IC50 value, ranged from 24.75–32.97 mg/ml. Chloroform and methanol extract of seeds showed anti-proliferative activity, with IC 50 value varied from 75.07–141.3 µg/ml. Solvent retention capacity of defatted seed meals ranged from 60.94 to 104.5 % (water), 86.87–137.39 % (sodium carbonate), 95.09–123.11 % (lactic acid) and 89.27–138 % (sucrose). WAC and OAC varied from 1.64–2.35 g/g and 1.97–2.13 g/g respectively. Solubility of DSMs varied from 20–35 %, maximal at alkaline pH. Likewise, emulsion activity and solubility also followed classic U-shaped curve and were highest at alkaline pH. The study concluded that muskmelon seeds being rich in protein and oil can be unconventional, sustainable, environmentally friendly and vegan sources of high quality protein and PUFA rich oil.