Effect of Substitution of Chicken Egg with Duck Egg on Biscuit Quality

Abstract. Eggs are characterized  with  other components such  antioxidants, folic acid and other B vitamins, and unsaturated fats which might have beneficial effects on heart disease risk that counterbalance the small adverse effect of the eggs’ cholesterol content. A specific study of the effect of chicken egg and/or duck egg in biscuit production has allowed the determination of their respective effects on baking, chemical and sensorial properties. Five sample blends of chicken and duck eggs were made respectively from the following ratios: 0, 10:90, 20:80, 30:70, 40:60 and 50:50%, respectively. Baking and nutritional properties of samples of   biscuit were determined by standard methods, while sensory evaluation was also carried out. The results on the biscuit samples revealed the following ranges: baking properties (weight 14.53-14.85g, diameter 48.4-50.04mm, thickness 9.37-9.46mm, bulk density 0.61 to 0.82g/cm3 and spread ratio 5.12-5.37;  proximate parameters (moisture 3.22-4.78%, ash 0.64-1.74%, fibre 0.49-0.51%,  protein 9.4-12.9%,  fat 15.8-19.2%,  carbohydrate 62.4-68.8% and energy 397.67-411.85kcal/g). Biscuit samples contained varying amounts of calcium, phosphorus, potassium, magnesium, zinc and iron. Baking properties showed a decrease in the weight and thickness but increase in diameter and spread ratio of the biscuits with rising levels of substitution. . The chemical analysis results revealed that biscuit samples containing different levels of duck egg had significantly higher fat, ash and protein content but lower moisture and carbohydrate than the control. Mineral concentration was significantly affected (p≤0.05) by the substitution with duck egg in the biscuit formulations. The substitution of chicken egg with duck egg at a level of up to 40% produces biscuit without any negative effect in quality attributes and reasonable acceptance. Conclusively, the substitution of chicken egg with duck egg in biscuit production is an ideal approach to utilizing uncommon food ingredients. The use of duck egg produced biscuit with different characteristics and quality, depending on level of inclusion in the formulation, offering nutritious and healthy alternative to consumers.