Chapter 5. Determination of moisture
Chapter 5. Determination of moisture
Section 1. General ◼ Moisture determiantion is one of important and most widely used measurements in the processing and testing of foods. ➢ Dry matter ➢ Stability and quality of foods ➢ Chemical reactions
Section 1. General ◼ Moisture determiantion is one of important and most widely used measurements in the processing and testing of foods. ➢ Dry matter ➢ Stability and quality of foods ➢ Chemical reactions
1. Water forms ◼ Free water ◼ Absorbed water ◼ Bound water
1. Water forms ◼ Free water ◼ Absorbed water ◼ Bound water
2. Methods of moisture determination ◼ Direct determinantion: remove the moisture in sample by the methods of drying, distillation and extration. ◼ Indirect detremiantion: using sample’s density, refraction, conductivity or capacitance to measure the moisture content
2. Methods of moisture determination ◼ Direct determinantion: remove the moisture in sample by the methods of drying, distillation and extration. ◼ Indirect detremiantion: using sample’s density, refraction, conductivity or capacitance to measure the moisture content
◼ Direct determination: good accuracy and repetition, but spending long time. ◼ Indirect determination: fast and automatic, but slightly week on accuracy
◼ Direct determination: good accuracy and repetition, but spending long time. ◼ Indirect determination: fast and automatic, but slightly week on accuracy