Cornflour/Cornstarch and Potato Flour

Our answer

Unfortunately for some ingredients the UK and the US use different terms for the same ingredients. We suspect that the recipe you are looking at is the UK version which will include the UK terms cornflour and potato flour. Cornflour in the UK is the same as cornstarch in the US. For the cheesecake the UK version of potato flour is indeed potato starch. It is a very fine, fairly bright white powder. And like cornstarch it is often used for thickening and in baking. It is made only from the starch of the potato.

However the US also has potato flour which is made from the whole potato (including the skin) and is coarser than potato starch as well as being more of a creamy colour. It is sometimes added to wheat flour in breadmaking and can be used for thickening sauces. It will tend to absorb more water than potato starch and can become gummy, so should not be substituted for potato starch in recipes.