Physicochemical and Sensory Properties, and In-Vitro Digestibility of Biscuits Made from Blends of Tigernut (Cyperus esculentus) and Pigeon Pea (Cajanus cajan)

Abstract

Objective: The study explored the potential of tigernut and pigeon pea flour blends in the preparation of biscuits. Materials and methods: Tigernut and Pigeon pea seeds were processed into flour and formulated into blends. The chemical composition of the flours and biscuits prepared from the flour blends as well as in- vitro (starch and protein) digestibility, physical and sensory properties of the biscuits were evaluated using standard methods. Results: The chemical composition such as protein, moisture, fat, ash, crude fiber, ash, energy, iron, calcium, zinc and phosphorus contents of composite biscuits ranged from (11.64 to 17.81%), (4.11 to 6.03%), (12.80 to 18.40%), (2.43 to 3.63%), (3.81 to 4.95%), (437.84to 453.36kcal) , (3.18 to 3.81mg/100g), (60.15 to 87.69mg/100g), (0.50 to 1.27mg/100g) and (223.19 to 248.17mg/100g) respectively and were significantly (p≤ 0.05) higher than 100 % wheat biscuit. The composite biscuits had poor starch digestibility (25.43 to 44.18 %) than 100 % wheat flour biscuit (57.25 %) as well as high protein digestibility (60.20 to 71.57 %). Biscuits prepared from tigernut and pigeon pea flour blends were significantly (p≤ 0.05) higher in width and spread ratio than control samples while their break strength decreased with increase in pigeon pea flour addition. There were no significant (p≥0.05) differences in appearance, flavour, crust colour and overall acceptability between composite biscuits and control. Conclusion: This study reveals that tigernut and pigeon pea flour could be used in the production of nutritious biscuit and confirms their potential as a functional food especially for diabetic and obese patients due to their low starch and high protein digestibility. Keywords: Chemical, in-vitro digestibility, mineral composition, ph