Briefly describe and address the problem or issue:

            The main issue concerned when it comes to storing frozen food, like ice kacang, is to maintain the temperature of the food so as to prevent it from melting. When these frozen food items are stored in normal plastic containers, heat enters by several ways, mainly conduction, convection and radiation, causing the frozen food items to gain heat and begin to melt.

          Frozen food items melt when they gain heat. These substances remain frozen only when its temperature is kept at or below its ice point. For example, in the ice of ice kacang, the temperature of the ice is to be kept at 0ºC or lower. This is so as the ice point, or the melting point of the ice is 0ºC. Hence, to keep its molecules vibrating slowly in a fixed position, a low temperature is required so as to not break the bonds holding these molecules together.

          Placing the ice kacang in a normal container can cause heat to enter through conduction, convection and radiation.

          Firstly, most of the heat gained by the ice kacang is through conduction. Conduction is the transfer of heat energy through a material medium, solid, liquid or gas, by the passing on of increased atomic and/or molecular vibrations from the hot end to the cold end. In the case of a normal plastic container, the following process occurs. When one end of the solid is heated, the particles at this end gain energy and vibrate faster. The neighbouring particles are jostled and made to vibrate more vigorously. This would then go on along the solid. After some time, the increased vibration is spread from the hot end to the cold end and eventually to the ice kacang. Hence, this would increase the temperature of the ice kacang, causing it to melt.

          Secondly, some heat is also gained by the ice kacang through convection. Convection is the transfer of heat energy by the bulk movement of fluid, liquid or gas, due to changes in density. In the container storing the ice kacang, there would be some air available. Hence, convection of heat is one of the factors leading to the melting of the ice kacang.

       

 Lastly, heat is also lost through radiation.

Radiation is the transfer of heat energy by the emission and absorption of infra-red rays. When an object radiates heat, it is said to emit radiation. The rate at which a body radiates heat would depend on its temperature and the nature of its surfaces. For example, a dull surface is a better emitter or radiator while a polished, shiny surface is a good reflector of radiation. Since the containers used to contain ice kacang are usually smooth and light coloured, they prove to be a very good radiator of heat.

          Therefore, the issue in storing ice kacang would be the TYPE, DESIGN AND TEXTUREof the containers that would be designed.