Hydration characteristics of wheat grain
Keywords:soaking, hydration, EMC, model
The hydration characteristic of wheat was studied by soaking in water at temperatures of 30 (room temperature) 50, 60 and 70 oC in constant temperature water bath. The weight gain due to the hydration process was determined in terms of moisture content (% d.b). Water absorption rate was high at the early stage of hydration (10-30 min depending on temperature) followed by a decreased rate and finally approaching equilibrium condition. Peleg's equation adequately described the hydration characteristics of wheat under the experimental condition (R2 = 0.95 to 0.99). The Peleg rate constant k1 decreased while Peleg capacity constant k2 increased significantly with an increase in temperature from room temperature to 70 oC, demonstrating that the water absorption rate increased and water absorption capacity decreased with increase in temperature. The agreement between experimental and estimated values of the hydration data (R2 = 0.97 to 0.99) confirmed that Peleg's equation could be used to describe the hydration characteristics of wheat under the experimental conditions considered.