Starch is a carbohydrate that has no taste or odour and is a substantial component of the human diet. Starch may be present in a variety of everyday foods such as rice, corn, and potatoes. The relative percentages of amylose and amylopectin in starch vary depending on the source of starch. When heated, starch produces a lyophilic solution with water. Starch molecules include an OH group that may create hydrogen bonds with water molecules. As a result of the attraction between starch and water molecules, it is a stable lyophilic solution. In water, starch particles are very soluble.
When cooked to a specific temperature, starch produces a lyophilic colloidal solution with water. In this part, we'll go through how to conduct the same thing in a chemical lab.
We will need the following items to produce the solution:
To carry out the experiment, we will need the following equipment:
First and foremost, we must select how many solutions we wish to prepare. Assume you wish to make the solution in 100ml of water. We'll need a modest amount of starch for this. As a result, you will need to weigh 0.5g to 1g of soluble starch using an electronic weighing machine or an electronic balance.
After weighing the starch, transfer the weighed amount to a mortar. Add a few mL of distilled water as well. Using a pestle, crush the starch into a thin paste. Fill a 50ml beaker halfway with the paste. Fill the bigger (250ml) beaker with 100 ml of distilled water. Place the wire gauze on top of the tripod support and the Bunsen burner beneath it. Start the burner and set the wire gauze over the 250ml beaker (with 100ml water). Heat the beaker until the water begins to boil.
When the water begins to boil, begin pouring the starch paste from the smaller (50ml) beaker. While stirring, use the glass rod continually. For around 10 minutes, bring the water and starch mixture to a boil. After that, set the beaker aside to cool.
After the solution has cooled in the beaker, we must filter it. To achieve this, take a funnel and fill it with filter paper. Pour the starch solution through the filter paper and funnel into a new vessel.
The lyophilic starch solution is therefore collected in the filtrate.
As you can see from the preceding section, it is not a particularly difficult experiment. However, there are a few factors you must consider to ensure the experiment's success.
First and foremost, please make certain that the apparatus (beakers, mortar, and other items) that you wish to use for this experiment is thoroughly cleaned. Any dirt or contaminants may cause the experiment to fail.
Both the starch and the water should be of high quality. Ascertain that the starch powder is clean and white in colour. For the experiment, always use distilled water. When making the starch paste in mortar, make sure there are no grains and that it is a fine paste.
Do not dissolve the starch paste in cold water. Wait for the water to begin to boil. When adding the paste to hot water, do it gently in a thin stream. Stir constantly to avoid the formation of any precipitates. Continue to whisk until the ingredients are completely dissolved in water.