how can i carry out starch analysis by extraction and sedimentation method.
assistance needed
To carry out starch analysis using the extraction and sedimentation method, you will need the following materials and equipment:
Materials:
1. Potato or any other starch-containing material
2. Distilled water
3. Iodine solution
4. Sodium chloride (salt)
5. Filter paper
Equipment:
1. Blender or mortar and pestle
2. Beakers
3. Glass rod or spatula
4. Funnel
5. Burette with stopcock
6. Stopwatch or timer
Here are the steps to perform starch analysis using the extraction and sedimentation method:
1. Preparation: Start by preparing a starch suspension. Peel and chop a potato into small pieces. Grind the potato in a blender or using a mortar and pestle until a smooth paste is obtained. Add distilled water to the paste and mix well to form a starch suspension.
2. Extraction: Transfer the starch suspension into a beaker. Stir the suspension using a glass rod or spatula to remove any air bubbles. Allow the suspension to settle for several minutes until a clear supernatant liquid is formed.
3. Sedimentation: Carefully pour off the clear supernatant liquid from the beaker. Leave behind the starch sediment at the bottom. Add a known volume (usually 10 mL) of distilled water to the beaker containing the starch sediment. Mix well to resuspend the sediment.
4. Filtration: Set up a funnel with a filter paper in a clean beaker. Pour the starch suspension through the filter paper, allowing the liquid to pass through while the starch particles get trapped in the filter paper.
5. Iodine reaction: Take the filtrate (liquid) and transfer it into a clean beaker. Add a few drops of iodine solution to the beaker. The iodine will react with any residual starch present, causing the solution to change color. The intensity of the color change corresponds to the amount of starch in the sample.
6. Calibration: If you want to determine the concentration of starch in your sample, you need to calibrate the method. Prepare a series of standard solutions with known starch concentrations using the same procedure described above. Measure the absorbance or intensity of the iodine-starch complex in each standard solution to create a calibration curve.
7. Analysis: Measure the absorbance or intensity of the iodine-starch complex in your sample using a spectrophotometer or colorimeter. Determine the concentration of starch in your sample by referring to the calibration curve you created in the previous step.
By following these steps, you will be able to carry out starch analysis using the extraction and sedimentation method.