Abstract:
To study the factors affecting the effective partition constant (K) of modeled mung bean flour washing water. The factors investigated were the concentration of protein solution (6.5 +- 1.0, 14.0 +- 1.0 and 19.0 +- 1.0 mg/ml), the rate of the progress of ice front (0.5, 1.0 and 2.0 cm/hr), and the stirring rate (200, 500 and 800 rpm). Moreover, the relationship between the K value and the concentration of protein solution obtained from this modeled solution was used to predict the changes in protein concentration of actual mung bean flour washing water from the vermicelli industry. At the protein concentrations of 6.5 +- 1.0 and 14.0 +- 1.0 mg/ml, the rate of the progress of ice front and the stirring rate were investigated in all 3 levels. However, at the protein concentration of 19.0 +- 1.0 mg/ml, the rate of the progress of ice front and the stirring rate were varied in only 2 levels (i.e., 0.5 and 1.0 cm/hr, and 500 and 800 rpm, respectively). At the conditions where the protein concentration was 6.5 +-1.0 mg/ml, the rates of the progress of ice front were 0.5 and 1.0 cm/hr, and the stirring rates were 500 and 800 rpm, the K values were nearly zero. The lowest K value was obtained when the rate of the progress of ice front was 0.5 cm/hr, and the stirring rates were 500 and 800 rpm, at the protein concentration of 14.0 +- 1.0 mg/ml. At protein concentration of 19.0 +- 1.0 mg/ml, the lowest K value could be obtained when using the lowest rate of the progress of ice front (0.5 cm/hr) in combination with the highest stirring rate (800 rpm). The linear relationship between the K value and the protein concentration obtained from the modeled solution could reasonably predict the concentration changes of waste protein solution from the vermicelli industry. Furthermore, this study also investigated the functional properties of mung bean protein from the modeled solution and of the resulting concentrated solution after being treated at the progress rate of ice front of 0.5 cm/hr and the stirring rate of 800 rpm. It was found that the solubility, the water adsorption value, and the emulsion activity index of mung bean protein from the modeled solution and those of the resulting concentrated solution were not significantly different (p>0.05). On the other hand, the oil adsorption value of the resulting concentrated protein was signifacantly higher than that of the protein of the original modeled solution (p<=0.05)