Starch stiffens fabric and produces crisp pleats, tucks and lines. Starching and then ironing fabric helps collars and ruffles stand out and produces a smooth finish on the fabric. Most laundry starch is made from cornflour, but you can also make starch from other ingredients. Making starch at home saves you money and allows you to create a recipe that meets your needs for stiffness in your fabric.
Peel a potato with a sharp knife. Cut out any eyes and remove any discoloured sections. For the whitest starch, use only the white part of the potato.
Grate the potato into a bowl. Pour 1 quart of water over the grated potato. Stir to remove the starch from the potato. The liquid will become cloudy. Pour the liquid through a strainer into a clean bowl and reserve the liquid and the grated potato.
Return the potato to the bowl and pour another quart of water over the potato. Stir to release the starch.
Let the potato and water rest in the first bowl while you check the second bowl, into which you poured the first potato water. The white starch should have settled in the bottom of this bowl. Carefully pour off the clear water at the top, leaving the starch at the bottom.
Strain the second batch of potato water into the bowl with the starch from the first pouring. Let this water sit while the starch settles out, about 30 minutes. Pour off the clear liquid.
Place the starch in a small saucepan and mix with one-quarter cup of cold water to form a smooth paste.
Pour in two cups boiling water, stirring constantly to keep the mixture smooth. Cook over medium heat, stirring constantly. Cook for two to three minutes.
Pour the prepared starch in a spray bottle and add one cup cold water. This makes a medium weight starch. Add more water for a lighter starch, and less for a heavier starch.
Place one cup of rice in a pot with one quart of water. Bring the rice and water to a boil.
Cook the rice until it turns to mush. Add more water as necessary and stir to keep the rice from sticking.
Remove the pot from the heat and add one quart of hot water. Stir.
Strain rice water through a piece of flannel. Store in a spray bottle. Discard the rice.