Evaluation Of The Quality Characteristics Of The Marama Bean (Tylosema Esculentum), An Underutilized Grain And Tuber Producing Legume In Southern Africa

ABSTRACT

The potential of the Marama bean plant, Tylosema esculentum (Burch.) Schreiber, a drought-tolerant, bean–bearing legume, native to Southern Africa, was investigated to potentially form part of a food-based approach in rural agricultural extension programmes. Nutrient content and sensory attributes of roasted Marama beans were determined as well as the potential of the Marama plant as fodder for cattle. Chemical analyses were performed on roasted Namibia and Botswana Marama beans to determine the nutritional content thereof. The beans contain high levels of protein, unsaturated fats, phosphorus, calcium, vitamin A, vitamin B3, vitamin B6, folic acid, vitamin B12, vitamin E, iron, zinc and iodine. Quantitative descriptive sensory analyses were performed on roasted marama beans from Botswana and Namibia to determine and compare the sensory attributes thereof. The Botswana traditionally roasted, Botswana oven roasted and Namibian oven roasted samples grouped together. The Namibian traditionally roasted marama bean had a significantly more intense burnt, bitter and chemical aroma and flavour and taste. To assess the value of the marama plant as a fodder for cattle, an experiment was conducted to measure the effect of season, stocking rate and frame size on the diet selection of the marama plant by cattle grazing the veld of the Sandveld Research Farm in the eastern part of Namibia. This study proved that only season had a significant influence on the selection of the marama plant as a feedstuff for cattle. The marama plant is indeed utilized by free-ranging beef cattle, but not preferentially so.