I need 1 1/4 cups of white rice flour for shortbread recipe, how much corn starch do I use as an alternative?

  • 2
    Welcome to SA! For folks to help you, they'll need to know the rest of the recipe you're using. For example ... if that's the majority of the flour in that recipe, it's not a substitution I would even try.
    – FuzzyChef
    Aug 17, 2021 at 19:27

3 Answers 3


White rice flour is basically pure starch. You can generally substitute it 1:1 with other starches, and that functions in the vast majority of recipes without any noticeable difference in the finished product.

There is indeed some difference in starches from different sources, but since nonwheat flours are not normed anyway, there will be as much difference between white flours made from different cultivars of the same plant, or made by different producers (brands) than as between one source and the next.

  • 1:1 by weight, but do they pack the same if measuring by volume?
    – Chris H
    Aug 19, 2021 at 12:30
  • @ChrisH It should work by volume too. The packing will depend mostly on grain size, which will depend more on the producer than on the plant. So, if the recipe works with corn starch from different producers (and from different corn cultivars), it should also work with rice starch. Not every mathematical difference is significant in the kitchen :)
    – rumtscho
    Aug 19, 2021 at 13:19
  • Here our rice flour is slightly coarser than our wheat flour, unless the main component of a blended gluten free flour; our corn starch (which we call corn flour) is far finer. Across all brands. So packing will differ - but we use weight. If places that use volume happen to have similar grinds, then great
    – Chris H
    Aug 19, 2021 at 19:32

This is not a substitution I would try, if the rice flour were the primary grain used in the recipe (that is, the majority of the flour).

White rice flour is not a pure starch. It contains some protein, non-dietary fiber, sugars, and minerals. This gives the rice flour body and structure and "bulk".

Whereas corn starch is almost a pure starch, with very little in it other than starch. This means that it "collapses" into a goo when mixes with water, and provides no structure at all to your baked goods. It's really only suitable for supplementing other flours, and certainly not as the major ingredient of shortbread. Even the classic Canada Cornstarch Shortbread contains twice as much wheat flour as corn starch.


You would need 1 1/4 cups cornstarch (Essentially what rumtscho said)

A cornstarch shortbread recipe would be
1 1/4 cups cornstarch (160 grams)
1/2 cup oil (107 grams)
1/4 cup sugar (53 grams)
Bake at 350F for 12 minutes

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