Physical, nutritional and antioxidant properties of Zimbabwean bambara groundnut and effects of processing methods on their chemical properties

Abstract

AbstractThis study examined the physical, nutritional and antioxidant properties of popular Zimbabwean bambara groundnut landraces and the effects of different processing methods on their chemical properties. The physical, nutritional and antioxidant properties of grains of the bambara landraces differed significantly with grain type, and the processing methods investigated had varying effects on the chemical properties of the grains. Bambara had significantly lower protein content than the reference common bean. Protein and carbohydrate content of the grains increased upon dehulling, while tannin (approx. 36%), total phenolic content (approx. 83%) and antioxidant activities (approx. 18%) decreased. Roasting alone seemed to have little or no effect on the nutrient content of the grains, while sifting significantly reduced the phenolic content and antioxidant activity of all the dehulled and roasted samples. The results indicate that roasting bambara grains would be a suitable method as it is relatively more conservative of nutrients and antioxidants than the other methods investigated.