Studies on compaction behavior of composite flours during uniaxial compression process of pasta making

The mechanical compaction behavior of composite flours during simulated direct compression process of pasta making was studied using a uniaxial compression test. Composite flours (decorticated minor millet flour viz., foxtail millet, little millet and kodo millet with refined wheat flour), blend in the ratio of 30:70, 40:60, 50:50 at 9 and 37% moisture contents (db) were subjected for compaction studies through instrumental (piston-cylinder assembly, D:H, 60:65 mm) measures with known applied pressure range (0 - 1477 kPa) and manual tapping procedures. The range of initial bulk density, critical bulk density, tap density and compressibility index for foxtail millet, little millet and kodo millet composite flours at 9 and 37% moisture content (db) were determined as 505 - 438 and 618 - 548 kg m⁻³, 1224 - 999 and 1539 - 1119 kg m⁻³, 778 - 658 and 733 - 649 kg m⁻³ and 39.34 - 3.22 and 38.29 - 10.07%, respectively. Data were analyzed statistically for its significance with different moisture levels and composite flour ratio. Pressure-density relationship for composite flours were established and validated with Peleg's equation (R² >0.948) to evaluate the compaction behavior of composite flour during pasta making