Production of high-protein extruded cassava snacks containing navy beans.
Abstract
Snack food consumption is on the rise due to people's hectic schedules and lack of time for meal preparation. However, most snacks are high in calories but low in other vital nutrients like proteins, minerals, fiber, and vitamins. Incorporation of pulses into starchy staples can enhance the nutrient density of the latter. In this study, navy beans (12.5-50%) were used to enhance the protein content of extruded cassava snacks. Extrusion was carried out at temperatures of 81, 93 and 89 degrees Celsius
(1st, 2nd and 3rd zones respectively), screw speed of 35 rpm and 5% added moisture. The extrudate properties (expansion index, bulk density, water solubility (WSI), water absorption index (WAI)), nutritional composition (carbohydrates, protein, dietary fiber, fat, ash, moisture content) and sensory acceptability (9-point hedonic scale) were evaluated. Inclusion of navy beans significantly affected (p < 0.05) the expansion index, bulk density, WSI, carbohydrate, protein, dietary fiber, fat, ash, moisture contents. WAI and consumer acceptability scores were not significantly affected (p > 0.05). The highest expansion index was observed in the 37.5% beans snack and the lowest was in the 100% beans snacks. Bulk density increased with increasing bean concentration. Carbohydrate content ranged from 51% (100% beans) to 83.8% (100% cassava). Protein, dietary fiber and ash increased with increasing bean concentration. The protein content increased from 1.7% (0% beans) to 10.8% (50% beans). Cassava extrudates containing up to 50% beans were
generally liked (6.5-7.5).
Navy beans can be incorporated in cassava to produce protein enhanced acceptable snacks.