How to Read the Protein Percentage on a Flour Label

The Nutrition Facts table appears on nearly every package and lists carbohydrates, fat, protein, and salt. Look for the protein row. The value is usually given per 100 grams of product; if it lists 11 grams of protein per 100 grams, the flour has 11% protein. Some packages give it per serving, in which case convert it to a 100-gram basis. If there is no protein row, or the product is sold in bulk, that information is unavailable and you will have to decide by testing it.

The number falls into one of three ranges. 12–14% is bread flour; it develops strong gluten, makes dough stretchy, and gives good volume. Flour with 10–11% protein is all-purpose flour; it works for many things, from bread to savory pastries, but does not produce an extreme result in any of them. Flour with 7–9% protein is cake flour; because its gluten stays weak, it gives cake, cookie, and pastry dough a soft, crumbly texture. The difference is only a few percentage points, but the result is very different. Products from the same brand can also fall into different ranges, so check the table again when you switch packages.

The pairing is simple. Doughs that need to be chewy, stretchy, and rise well—such as bread, pizza, Turkish flatbread, and sesame-crusted bread rings—need high-protein flour. In cake, cookie, tart, and pastry dough, gluten is a drawback; use low-protein flour there. Savory layered pastries, soft buns, and Turkish dumplings work well with all-purpose flour. If the flour you have is in the wrong range, it can be adjusted by blending: mixing cake flour and bread flour half and half produces flour close to all-purpose.

Protein alone is not enough; there are a few other things to check on the label. The flour type or number indicates how finely it was milled and how much bran it contains. A whole-wheat label means the bran remains in the flour, which can make dough behave very differently even at the same protein percentage. Check the production date, too: as flour sits, it absorbs moisture and the same recipe can behave differently. Finally, the package gives storage conditions and usually calls for a cool, dry place.

You can also work with flour that has no protein information on its label, but you will need to rely on testing. Make a small dough with a little flour and knead it by hand; if it comes together quickly and stretches thin without tearing, it is high in protein, while dough that tears quickly and stays slack is low in protein. Another way is to adjust the dough with water: high-protein flour absorbs more water, and low-protein flour absorbs less. Add the water gradually, not all at once. If you are buying loose flour from a counter, ask the seller; asking whether it is whole-wheat or bread flour will at least narrow down its range.