Starch extracted from potatoes and dried to a fine, squeaky powder. Its granules are unusually large, which is why it swells fast and thickens at a low temperature.
What it does in a recipe: Very fast, very clear thickening at low heat, with no flavour of its own. Pick the swap that covers that job - the ratios below are written so you can act on them without doing any arithmetic.
Also called: Potato flour (not the same thing), Kartoffelmehl
4substitutes
2close matches
Thickenerscategory
Quick answer
Cornstarch
1 tbsp potato starch = 1 tbsp cornstarch
All substitutes, best first
4 ways to replace potato starch
Cornstarch
Closest match
1 tbsp potato starch = 1 tbsp cornstarch
Comparable thickening power spoon for spoon, and considerably more tolerant of heat, so it holds up in a sauce that has to sit on the stove or be reheated.
MethodBring it to a proper simmer for a minute to gelatinise fully, which potato starch never needs.
Trade-offSlightly cloudier and less glossy, and it takes longer to reach full thickness.
Allergen checkContains wheat. Potato starch is frequently chosen precisely because it is gluten-free and Passover-friendly, so this substitution undoes the reason for using it - check what the cook actually needs before reaching for flour.
Worth knowing
Potato starch cannot take a hard boil. Its large granules rupture under sustained heat and the sauce thins right back out, sometimes in under a minute. Add it at the end, off the heat, and serve. Note also that potato starch and potato flour are different products - potato flour is dried whole potato and will make a sauce heavy and potato-flavoured.
At a glance
Potato starch in summary
Potato starch at a glance: category, its job in a recipe, the diets it suits, the diets its substitutes can satisfy, and how many substitutes there are.
1 tbsp potato starch = 1 tbsp cornstarch. Comparable thickening power spoon for spoon, and considerably more tolerant of heat, so it holds up in a sauce that has to sit on the stove or be reheated. Slightly cloudier and less glossy, and it takes longer to reach full thickness.
Can I use tapioca starch instead of potato starch?
1 tbsp potato starch = 1 tbsp tapioca starch. Another clear-setting root starch that thickens quickly at moderate temperature, with the added benefit of freezing and thawing cleanly. Slightly stringier in texture and a touch sweeter, though the visual result is much the same.
Can I use arrowroot starch instead of potato starch?
1 tbsp potato starch = 1 tbsp arrowroot starch. Similar low-temperature clear set and similar thickening strength, and arrowroot handles acidic liquids better than most alternatives. Shares potato starch's dislike of dairy, turning slippery in a cream sauce.
Can I use all-purpose flour instead of potato starch?
1 tbsp potato starch = 2 tbsp all-purpose flour. Only about half of flour's weight is starch, so twice as much is needed to reach the same viscosity. Opaque and matte with a cereal note, so it changes the appearance of a clear sauce entirely.
Cooking around an allergy? Diet tags here describe the ingredient itself, not any particular brand. Processed products change formulation without notice and shared production lines are common, so read the label on everything you use. A severe allergy is a medical matter - confirm with the manufacturer or your clinician rather than relying on a substitution chart.