Production and Quality Evaluation of Gluten Free Biscuits from Maize and Soybean Flour Blends

Abstract

The study evaluated the quality of gluten–free biscuits made from maize and soybean flour blends, and compared them with 100% wheat flour biscuit. Flours were prepared from maize and soybean grains. The soybean flour was used to substitute 5, 10, 15, 20 and 30% of maize flour in order to obtain various flour blends. The chemical composition, functional and pasting properties of the flours and their blends were determined. The flour blends were used to prepare biscuits, which were analyzed for the chemical composition, physical and sensory properties. The results showed that the moisture, protein, fat, fiber, ash, and carbohydrate contents of the flours ranged from 10.58-11.37, 7.30-42.23, 1.82-10.15, 0.34-5.20, 0.85-4.00, 27.84-76.41%, respectively. The phosphorus, iron and magnesium contents varied from 1.24-166.96, 2.31-19.54, 0.01-157.56mg/100g, respectively. The bulk density, foaming capacity, water absorption and oil absorption capacity of the flours and the blends ranged from 0.66-0.68g/cm3, 3.22-29.25%, 85.00-210.00g/g and 80.0-145g/g, respectively. The peak viscosity, trough viscosity, breakdown viscosity, final viscosity, setback viscosity, peak time and pasting temperature decreased with an increase in the level of soybean flour incorporation and ranged from 113.05-127.98, 83.95.97.05, 23.99-41.95, 224.02-409.98, 136.01-325.03, 6.12-7.05, and 55.4-95.0 RVU, respectively. The moisture, protein, fat, fiber, ash, and carbohydrate of the biscuits increased from 4.10-9.19, 34.94-40.38, 27.24-31.39, 6.88-7.93, 0.53-3.79, and 16.99-23.44%, respectively. The phosphorus, iron, and magnesium contents of the biscuits ranged from 47.01-65.91, 3.37-7.08, 0.0018-0.0047mg/100g, respectively. The sensory scores for the biscuit samples decreased with the level of soybean flour. However, the biscuits containing 10% soybean flour was not significantly (p>0.05) different from the 100% wheat flour biscuits in all the sensory attributes evaluated. Therefore, comparable biscuits with 100% wheat biscuit could be produced from the blend of 90 % maize flour and 10% soybean flour.