Water has definite freezing point, either the solution which varies on solute concentration. Unfortunately, the group didn’t get the time for total solidification, yet we all know that the presence of solutes will give lower freezing point than that of water. This gives us the idea of freezing point depression, a colligative property of solutions. According to De Man, solutes are found to depress the nucleation temperature to the same extent as they depress the freezing point. On freezing process, volume will increase considering moisture content, concentration of solute, and the freezer temperature. (Fellow, 1990) High concentration of solutes reduce freezing point, and neither freeze nor expands. Crystallized components such as fats and solutes, when cooled, it bonds and lowers the volume of the solution. The more volume it increases, the harder it gets because of the water content. Since, approximately 50% of water content turns to ice. So, like in this experiment, the more concentrated the solution was, it has a soft texture and creamy feeling. Upon thawing and refreezing can create large ice crystals causing an undesirable grainy or gritty texture and diminished quality. So, it is not advisable to thaw and refreeze.
Water activity and MC are both related to the stability of most products. Both also determine the specific changes in color, aroma, flavor, texture, stability, and acceptability of raw and processed food products. Both the water content and the water activity of a sample must be specified to fully describe its water status.
In the freezing process, greater cooling speed is recommended for producing a fine crystal structure, which gives desirable quality. One must also take note of the temperature, solute concentration and water content, because it affects solution’s volume and texture. Indeed, it is recommended to produce an ice cream or products which are freshly frozen than thawed and refrozen.
The results were expected to be that high moisture contents and high water activity would hasten enzyme activity. Clearly stating that just by leaving mung beans with water for a few hours will surely have a significant change in its overall state, unlike some foods that just get soft overnight with water.
The results were that the mung beans with more moisture were able to change in its aroma, flavour, and to its texture. For better results, only use about a teaspoon of mung beans per sample or increase the amount of distilled water added so that the results will be more evident.