Effect of drying methods on the functional, physicochemical, pasting, and sensory properties of unripe plantain flour and its cooked paste (Amala)

Abstract

The effects of drying methods on the functional, chemical, pasting, and sensory properties of unripe plantain flour and its cooked paste (amala) was investigated. Grated, dewatered and pulverized unripe plantain wet cake were dried using flash, solar, and sun drying to generate flour. Functional, physicochemical, pasting, and sensory properties of amala paste, were assessed. Values obtained were 5.90 to 9.91 for moisture, 80.51 to 85.78 for carbohydrate, 1.92 to 2.92 for crude fat, 1.85 to 3.53 for crude protein, 1.30 to 2.25 for ash and 1.38 to 2.22 for crude fibre. The lowest moisture content was obtained in the flash-dried sample. Sun and flash-dried samples gave the highest iron, sodium, and potassium values. The highest values for total starch, resistant starch, and amylose contents were obtained in flash and sun-dried samples, solar dried samples gave the lowest values. Flash-dried flour showed significantly high values for water absorption capacity. Flash and sun-dried flour showed significant values for wettability, while flash and solar-dried flours had high values for dispersibility, bulk density, and swelling index at 60, 70, 80 and 100°C (6.31, 6.36, 6.69 and 6.84 respectively). Sun-dried samples had the highest values for swelling power at 70, 80, 90, and 100°C (10.70, 10.73, 13.53, and 14.46, respectively). Flash- dried flour had the highest peak, trough, and final viscosity values for the pasting profile. Sensory scores showed that flash-dried amala had highest scores, while its flour had desirable proximate composition, functional and pasting properties.