Effects of Blanching with Chemical Preservatives on Functional and Antioxidant Properties of Fluted Pumpkin (Telferia occidentalis) Leaf

Abstract

Fluted pumpkin leaves were blanched with different salt solutions, sodium chloride (FPCT), sodium benzoate (FPNB) and ethylenediamine tetra-acetic acid (FPEB) and combined salt solutions (FPCM), unblanched leaves (FPUB). The samples were evaluated for chemical composition, functional properties, mineral compositions and anti-oxidative properties. The results of the proximate composition showed that the highest protein (36.32%) and ash (9.98%) contents were recorded in FPUB, while the highest fibre content (6.70%) was found in FPCT. The results of functional properties showed that the highest foaming capacity (4.23%) and stability (2.09%) was obtained in FPEB while FPUB had the highest water (364.77 %) and oil absorption (207.66 %) capacity and emulsion capacity (80.80 m2/g). The highest vitamin C content (184.00 mg/100g) was obtained in FPUB. FPED, FPCM, FPCT and FPUB had the highest potassium (3007.50 mg/mg), sodium (2130.80mg/100 g), iron (917.10 mg/100 g) and calcium (388.50 mg/100 g)  contents respectively. FPUB had the highest phenolic content (700.00 mg GAE/100g leaf extract) while FPED exhibited highest free radical scavenging ability (83.50%). In general, blanching of fluted pumpkin leaves with salt solutions resulted in improved nutrient retention capabilities as well as enhancement of some functional properties.Keywords: Phenolic content, vitamin C, salt solutions, emulsion capacity