science
2. Objectives
The objectives of this experiment are to observe the keeping quality of some food products, study the various simple methods of moisture determinations using different drying method. And determine the water activity in some food samples such as biscuits, bread, flour and instant noodles by using water activity measurement machine.
3. Theory
To determine the moisture content in the food, methods such as open dish method and infrared balance method are used.
3.1 Hypothesis of Experiment
This report was written to investigate and discuss the results (moisture content and water activity) obtained from this experiment and the possible storage methods to keep the foods safe from chemical, microbiological and physical spoilage due to the presence of water in the foods. At the end of the experiment, the theoretical moisture content in the flour should not be more than 14.5% and the water activity for bread, flour, biscuits and instant noodle should be 0.95, 0.352-0.35, 0.30 and 0.342-0.497.
3.2 Drying Oven
Drying oven is a common method used to calculate the moisture content in food products and the principle used in oven drying method is through the evaporation of water by the hot air in the oven. Thus, when a sample is placed inside the oven, water molecules in the sample will be evaporated and the moisture content can then be determined by the difference between it initial weight and dried weight. However, this method is time-consuming and needs a longer period of time to obtain accurate results.
3.3 Infrared Balance
Infrared Balance provides a primary method for accurate moisture measurement by using the loss on drying (LOD) method and the principle of this method is through infrared radiation and during the drying process, the sample will absorbed the heat energy produced from the infrared rays to dry the sample. In addition, during the drying process, the weight loss by the sample will be calculated automatically
The objectives of this experiment are to observe the keeping quality of some food products, study the various simple methods of moisture determinations using different drying method. And determine the water activity in some food samples such as biscuits, bread, flour and instant noodles by using water activity measurement machine.
3. Theory
To determine the moisture content in the food, methods such as open dish method and infrared balance method are used.
3.1 Hypothesis of Experiment
This report was written to investigate and discuss the results (moisture content and water activity) obtained from this experiment and the possible storage methods to keep the foods safe from chemical, microbiological and physical spoilage due to the presence of water in the foods. At the end of the experiment, the theoretical moisture content in the flour should not be more than 14.5% and the water activity for bread, flour, biscuits and instant noodle should be 0.95, 0.352-0.35, 0.30 and 0.342-0.497.
3.2 Drying Oven
Drying oven is a common method used to calculate the moisture content in food products and the principle used in oven drying method is through the evaporation of water by the hot air in the oven. Thus, when a sample is placed inside the oven, water molecules in the sample will be evaporated and the moisture content can then be determined by the difference between it initial weight and dried weight. However, this method is time-consuming and needs a longer period of time to obtain accurate results.
3.3 Infrared Balance
Infrared Balance provides a primary method for accurate moisture measurement by using the loss on drying (LOD) method and the principle of this method is through infrared radiation and during the drying process, the sample will absorbed the heat energy produced from the infrared rays to dry the sample. In addition, during the drying process, the weight loss by the sample will be calculated automatically