Effect of Germination Duration on the Chemical Composition, functional and Pasting Properties of Acha Flour and its Potential for Biscuit Production

Abstract

Germinated acha flour was prepared by washing the acha grain (with tap water), soaking(for 6hours), drained, spread evenly on jute bag to germinate for varied duration(0, 12, 24, 36 and 48 h). The varied germinated grains were dried in a hot air oven at 60oC, milled, sieved and packaged in high density polyethylene. The functional, proximate, pasting, mineral and vitamin properties of the germinated flour were determined using standard laboratory procedures. Biscuit produced from the germinated acha flour were also analysed for physical and sensory properties. Biscuit with 100% wheat flour (WF) serves as a reference sample. The proximate results of the flour showed an increase in protein (15.38% to 12.93%), ash (3.54% to 0.58%), fat (8.08% to 5.12%), crude fibre (0.32% to 0.22%), but decrease in moisture (11.46% to 10.15%), carbohydrate (69.19% to 64.56%) content with increase in germination duration. The pasting properties of the flour, peak viscosity, trough, breakdown, final viscosity, set back, peak time and pasting temperature decreased from 1457.01 to 348.01, 1147.07 to 152.02, 310.01 to 164.02, 3306.02 to 569.01, 2159.02 to 417.02, 5.60 to 5.08 and 1397.44 to 289.17 RVU, respectively, with increase in germination duration. There was remarkable increase in the iron, zinc, vitamin B1and B2 content from 22.02 to 93.24, 49.01 to 69.01, 0.615 to 1.633 and 0.163 to 0.483mg/100g, respectively, and a decrease in the calcium and phosphorus content from 24605.53 to 18498.55 and 1124.94 to 894.960 mg/100g, respectively, with increase in germination time. The weight and spread ratio of the baked germinated acha flour increased from 11.73g to 11.43g and 4.80 to 4.27, respectively, while the break strength and the volume of the same, increased from 2.47 to 2.83kg and 60.43 to 61.58cm³ respectively, with increase (1-5days) in germination duration. All the sensory parameters of the biscuits assessed with exception of taste were accepted and compared favourably with the control (100% wheat biscuit).