Potato Starch

Potato starch is the refined starch extracted from potatoes, with most of the protein, fiber and vitamins removed. Tufts veterinary nutritionists say cats can digest and metabolize properly cooked carbohydrates, while adult cats have no specific requirement for them. Kibble is cooked during manufacture, so the starch in it is cooked. For a cat with diabetes or another condition, ask your veterinarian.

Source: sites.tufts.edu

Potato starch binds grain-free kibble and helps it hold its shape after cooking. It is used in place of grain starches such as rice or corn. Pettings notes that it is nearly pure carbohydrate, so it adds energy but few other nutrients, and that grain-free foods using it can still be high in carbohydrate.

Potatoes on a label means the whole tuber, cooked and usually dried, so it keeps some fiber and potassium along with its starch. Potato starch is the extracted starch alone. Pettings scores potatoes 2 out of 5 and potato starch 1 out of 5, mostly because the starch has lost the little else that the potato offered.

Raw potato starch is high in resistant starch, the kind that escapes digestion in the small intestine. Cooking changes this, because heat and water gelatinize the starch granules and make them digestible. Dry cat food is cooked under heat and pressure, so the potato starch in kibble behaves mostly like ordinary digestible starch rather than resistant starch.

Pettings scores potato starch 1 out of 5 and lists it as a starch or refined grain. We found it on 3 of the 149 dry cat foods in our list. The ingredient score is separate from a food's overall score, which you can see on each food's page.