FLOW PROPERTIES OF MALT CONCENTRATE-SWEETENED CONDENSED MILK MIXTURES

The rheological characteristics of various malt extract concentrate-sweetened condensed milk mixtures in the ratios of 50:50, 60:40, 70:30 and 80:20 (w/w) were studied at 30 to 80C, using a coaxial viscometer. The magnitudes of flow behavior index varied from 0.42–0.93. Experimental temperatures and concentrations of sweetened condensed milk considerably affected pseudoplasticity, consistency index and yield stress values of the mixtures. At 60 to 80C, the 60:40, 70:30 and 80:20 mixtures showed spectacularly higher flow behavior index values than those of the 50:50. The yield stress values increased with increasing temperature. The increases were considerably high in the 50:50 mixtures. The hulless barley malt concentrate-sweetened condensed milk mixtures, however, were mildly non-Newtonian and showed decreases in the values for yield stress with increasing temperatures. The activation energy values for flow behavior index and yield stress were negative in magnitudes, whereas those of consistency index were positive, which ranged from 1.6 to 15.0 Kcal/g mole.