Many years ago before starch was manufactured in Ireland people made their own starch from raw potatoes. This was made as follows.
Six raw potatoes were peeled and washed, then grated into a basin. Afterwards they were put into a white cloth and wrung out. The juice of the potatoes was then put into a large basin into which clean water was poured.
This was then let stand for about half an hour at the end of which time the water is drained off and more added. When this was let stand for the second time and the water drained off again what remained in the basin waas of a white colour and used as starch. This home made starch is still used in many parts of the country.