The Effect of Drying and Salting on the Nutrient Composition and Organoleptic Properties of Talinum triangulare Leaves
Fred Omon Joseph Oboh *
Department of Basic Sciences, Benson Idahosa University, P.M.B. 1100, Benin City, Nigeria
Gift Ejehiokhin Madojemu
Department of Basic Sciences, Benson Idahosa University, P.M.B. 1100, Benin City, Nigeria
*Author to whom correspondence should be addressed.
Abstract
Aims: The present study was undertaken to determine the effects of drying and salting on the nutrient content and sensory properties of Talinum triangulare leaves.
Study Design: The methods of drying and salting were: oven drying to constant weight at 40°C without any pretreatment, blanching in steam prior to oven drying to constant weight at 40°C, light salting (25 g dry salt/ kg leaves), light brine and vinegar treatment (50 g salt / L +50 ml vinegar/ kg leaves), and heavy salting (250 g/ kg leaves). Each salt treatment was provided for a duration of 14 days.
Methodology: Moisture, pH, ash, Ca, Fe, Na, crude fibre, β- and total carotene and vitamin C content of the fresh leaves and the products of the treatments were determined. Values for the fresh and the treated leaves on one hand, and those for products of the various treatments were then compared statistically. Sensory characteristics were also recorded.
Results: Compared with the fresh vegetable, oven drying, alone or after blanching of the leaves, resulted in a decrease in nutrient content, with retention ranging from 22.08% (for vitamin C in the leaves dried without prior blanching) to 95.69% (for Na in the blanched and oven-dried samples). Blanching prior to drying gave higher retention of β-carotene, total carotene and vitamin C than oven drying alone, but offered no advantage over the latter for the preservation of ash, iron, sodium and calcium (minerals). Compared with the fresh vegetable, salting resulted in high loss of β-carotene, total carotene, vitamin C and iron, and an increase in sodium and calcium.
Keywords: Water leaf, blanching, salting, quality characteristics, drying