Instant soups from cowpea varieties using foam-mat drying

Abstract

The effect of glyceryl monostearate (GMS) concentration (50, 100, 150, 200, and 250 mg/kg) on foam density of cooked paste, and functional and sensory properties of instant soups from four cowpea varieties (Sokoto, Drum, Honey and Mala beans) was evaluated. The foam density decreased with increased glycerol monostearate (GMS) concentration across the varieties. Foam density (0.49–1.05 g/mL) of the cooked paste varied with glycerol monostearate concentration and cowpea variety. Swelling capacity (14.0–36.5 g/mL), water absorption (2.5–3.6 g/mL), oil absorption (1.1–1.7 g/mL), loose (0.6–0.8 g/mL) and packed (0.8–1.1 g/mL) bulk densities of the instant cowpea soup powders were significantly affected (p < 0.05) by the GMS concentration and variety. The L* (70.7–94.3), a* (−1.7-1.4), and b* (17.3–21.5) parameters of the foam-mat dried (instant soups) powders were significantly affected by cowpea varieties and GMS concentration. Sensory evaluation conducted on the reconstituted powder and freshly made soup were significantly different. Among the reconstituted foam mat dried (instant soups) powders, reconstituted cooked paste from Drum cowpea variety with 50 mg/kg GMS was the most preferred by the panellists (6.8). Foam mat drying of cooked cowpea paste could be reconstituted into acceptable instant soup.