STARCH POTATO
Potato starch is starch extracted from potatoes. The cells of the root tubers of the potato plant contain leucoplasts. To extract the starch, the potatoes are crushed, and the starch grains are released from the destroyed cells. The starch is then washed out and dried to powder.
potato starch is primarily used in canned soups and in blends where its thickening power is exploited, especially for fill viscosity. It is also used as a base for gelling agents in confections, for thickeners in products like pastry and pie fillings, and in instant puddings.
The best cornstarch substitute is potato starch. It has the right structure to provide the crispy and rigid coating that cornstarch does.Potato starch can be heated to high temperatures and it won't burn which makes it perfect for deep frying food.
The first aisle to check for potato starch is the aisle with kosher foods. These are typically in the international aisle. You can also check the baking aisle. If it's there, it will probably be with the cornstarch and flours.