Effects of banana peel-ash-extract on cooking time and acceptability of hard-to-cook beans (Phaseolus vulgaris l.)

Abstract

Beans are among the most important crops that contribute substantially to the agricultural sector and household food security in Uganda. Kawanda (K) 132 (Nambale) is presently a major bean (Phaseolus vulgaris L.) variety of high nutritional value. However, the hard-to-cook (HTC) defect limits its utilization, requiring appropriate processing to preserve the nutrients. Banana peel ash-extract, widely used in indigenous processing of dry beans, was evaluated for chemical composition and potential in reducing cooking time of beans with HTC defect. The peel ash-extract was found to contain substantial amounts of sodium (0.36 g/ml), chloride (0.07 g/ml) and magnesium (0.04g/ml) ions. Calcium, iron, copper, zinc, sodium and phosphorus were also found in detectable amounts. Generally, addition of the peel-ash-extract was found to reduce the cooking time of K132 beans. The cooking time of K132 beans, processed in ash-extract (0.31 g/ml), reduced by 52.3%. Reduction in cooking time was also found to correlate strongly (R2=0.89) with the pH of the ash-solution. Processing of K132 beans in ash-solution of pH G 11 reduced the cooking time by nearly 50%. Sensory attributes of dry beans cooked in banana peel ash-extract were preferred to that cooked in ordinary water. Beans cooked in peel ash-extract at a concentration of 0.23 g/ml were the most preferred (5.81±0.59) to that boiled in ordinary water (4.71±0.26). The taste, flavor and acceptance scores were, in general, higher in beans processed in ash-extract than that of ordinary water. The appearance, consistency and texture of cooked beans were not significantly different (p<0.05). Overall, processing of dry beans in banana peel ash-extract reduces cooking time and imparts desirable sensory attributes.

Keywords: Banana peels, ash-extract, hard-to-cook beans, cooking time, sensory attribtes

Keywords: Banana peels, ash-extract, hard-to-cook beans, cooking time, sensory attribtes