Nutritional, Phytochemical and Sensory Evaluation of Functional Biscuits from Tigernut (Cyperus esculentus) and Afzelia africana Flour Blends
Comfort Chinenye Nwagbo
*
Department of Food Science and Technology, Faculty of Agriculture, Chukwuemeka Odumegwu Ojukwu University, Anambra State, Nigeria.
MaryCynthia Obioma Iloka
Department of Food Science and Technology, Faculty of Agriculture, Chukwuemeka Odumegwu Ojukwu University, Anambra State, Nigeria.
Ijeoma Angela Ugwu
Nutrition Research and Education Unit, Integrated Healthcare Professionals Ltd, Citibase 61-67 Lewisham High Street Lewisham, London SE13 5Jx, United Kingdom.
Paul Abuchi Nwafor
Department of Food Science and Technology, Faculty of Agriculture, Chukwuemeka Odumegwu Ojukwu University, Anambra State, Nigeria.
Josephat Ikechukwu Anyadioha
Department of Food Science and Technology, Madonna University, Enugu, Enugu State, Nigeria.
*Author to whom correspondence should be addressed.
Abstract
Aims: Tigernut (Cyperus esculentus L.) and Afzelia africana are nutritionally rich, gluten-free indigenous crops. The unexplored functional food potential in composite biscuit production needs to be studied to address protein-energy malnutrition, micronutrient deficiencies, and rising consumer demand.
Study Design: This original research article used a completely randomized design (CRD). Biscuits were produced by substituting tigernut flour with Afzelia africana seed flour in this order: Control sample = 100% Tigernut flour; A = Afzelia africana (10%) + Tigernut (90%) flour; B = Afzelia africana (20%) + Tigernut (80%) flour.
Place and Duration of Study: The study was conducted in the Food Science and Technology department's laboratory at Chukwuemeka Odumegwu Ojukwu University, Igbariam Campus, in June 2024.
Methodology: Flour preparation and baking followed standard methods. Proximate composition, minerals, vitamins, phytochemicals, DPPH radical scavenging activity, and sensory acceptability were studied.
Results: Increasing Afzelia africana substitution was associated with significant dose-dependent increases in crude protein (3.66-5.52 g/100g), crude fiber (0.48-2.29 g/100g), crude ash (1.05-2.78 g/100g), calcium (172.18-273.62 mg/100g), magnesium (34.52-38.70 mg/100g), potassium (290.72-305.76 mg/100g), thiamine (0.51-0.88 mg/100g), riboflavin (0.43-1.08 mg/100g), niacin (0.16-1.17 mg/100g), total phenolic (12.87-16.82 mg GAE/100g) and flavonoid (4.49-6.69 mg/100g) content, alongside a progressive reduction in DPPH IC50 indicating enhanced antioxidant activity. All moisture values (3.49-5.31 g/100g) were within the recommended range for biscuit shelf stability. The control and sample A were not significantly different (p<0.05) in color, flavor, aftertaste, and overall acceptability.
Conclusion: Afzelia africana seed flour enhanced the nutritional value, antioxidant activity, and sensory appeal of tigernut biscuits. A 10% substitution of Afzelia africana seed flour was identified as the optimal formulation. These findings support the use of Afzelia africana seed flour as a functional food ingredient in biscuit production for protein- and micronutrient-vulnerable populations in Nigeria.
Keywords: Functional biscuits, tigernut flour, Afzelia africana, antioxidant activity, phenolic content, underutilized legume, Nigeria