Physicochemical Characteristics of Biscuits Produced from Gluten-Free Amaranth Seed and Tiger Nut Composite Flour

Abstract

This study was carried out to advance the use of indigenous composite flour obtained from amaranth seed and tiger nut in the production of biscuits to increase access to a healthy and sustainable diet. Biscuit was produced from amaranth seed flour substituted with tiger nut flour at 0%, 10%, 20%, 30%, 40% and 50%. The functional and pasting properties of the flour samples were determined, the proximate composition was evaluated and selected minerals contents of flour and biscuit samples were also assessed using standard methods. The results showed that the protein, fat, ash and fibre content of amaranth seed flour increased from 13.86%, 4.12%, 1.77% and 1.26% respectively to a range of 13.86 – 16.16%, 4.47 – 5.18%, 2.18 – 2.65% and 2.35 – 3.96% respectively with the addition of tiger nut flour. An increase in protein, fat, ash and fibre was also recorded in the biscuit samples with the increased concentration of tiger nut flour. Flour and biscuits produced from 100% wheat had lower protein, fat and fibre content than 100% amaranth seed flour and the blends. The bulk density and water absorption capacity of 100% amaranth seed flour and the blends were significantly higher than 100% wheat flour. Biscuits produced from amaranth seed flour substituted with tiger nut flour at 50% had the highest content of sodium (202.59 mg/100g) and potassium (299.57 mg/100g). In comparison, 100% wheat biscuit and 100% amaranth biscuit had the highest calcium (186.67 mg/1000g) and iron content (4.13 mg/100g) respectively. The study concluded that amaranth seed and tiger nut flour blends could be utilized to produce high-nutritional quality gluten-free biscuits that will increase access to an affordable healthy and sustainable diet.

Keywords

• amaranth seed
• tiger nut
• pasting properties
• proximate composition
• gluten