Effect of processing methods on some nutrients, antinutrients and toxic substances in amaranthus cruentus.

ABSTRACT

The presence of antinutrients and toxic substances severely limits the nutritional benefits of vegetables. The objective of this study was to assess the effects of processing methods on some of these substances. Effects of boiling and sun drying on oxalate, cyanide and nitrate, vitamin C, β-carotene, and the mineral elements Fe, Cu, Mg, Na and K in Amaranthus cruentus were investigated. Both methods significantly (p < 0.05) reduced oxalate, cyanide and nitrate levels. Vitamin C content was significantly (p < 0.05) decreased. β-carotene level increased on boiling but was reduced in sundried vegetable. Boiling exceeding 5 minutes significantly (p < 0.05) reduced β-carotene level. The mineral elements decreased upon boiling but sun drying had no significant effect on their levels. We conclude that both methods are effective means of reducing the levels of antinutrients and toxic substances in Amaranthus cruentus to tolerable levels with boiling being a better method.