What’s the Difference Between Bleached and Unbleached Flour?

Bleached and unbleached flour differ in certain ways, including processing, taste, texture, and appearance.

Processing

One of the most notable differences between bleached and unbleached flour is the way that they’re processed.

Bleached flour is typically refined, meaning that the nutrient-rich bran and germ of the wheat kernel have been removed, stripping the grain of many of its valuable vitamins and minerals and leaving only the endosperm.

Unbleached flour can include any type of flour, which may or may not be refined.

Both types are then milled, which is a process that involves grinding grains, such as wheat, into a fine powder.

Next, bleached flour is treated with chemical agents like benzoyl peroxide, potassium bromate, or chlorine, which helps speed up the aging of the flour. Flour is aged to improve certain qualities for baking.

This chemical process significantly changes the taste, texture, and appearance of the final product, as well as its nutritional profile and potential uses in baking.

On the other hand, unbleached flour is aged naturally after the milling process is completed. Natural aging takes significantly longer than the bleaching process, which is why bleached flour was created.

Unbleached flour is used in certain recipes due to its distinct texture.

Both varieties are sometimes enriched, which is the process of adding certain nutrients back into the flour (1).

Characteristics

The bleaching process produces many changes in the taste, texture, and appearance of flour.

The chemicals used to speed up the aging process in bleached flour cause it to have a whiter color, finer grain, and softer texture.

Conversely, unbleached flour has a denser grain and tougher texture.

It also tends to have an off-white color, which fades naturally as it ages.

Though there are minimal differences in taste between the two varieties, people with a very sensitive palate may notice a slightly bitter taste in bleached flour.

Summary

Bleached flour has a whiter color, finer grain, and softer texture, while unbleached flour has a denser grain and tougher texture. Bleached flour is treated with chemical agents to speed up the aging process.

The nutritional values of bleached and unbleached white flour are nearly identical.

Both varieties contain the same number of calories and amounts of protein, fat, carbs, and fiber per cup (125 grams).

The bleaching process may decrease the vitamin E content slightly, but unbleached flour still contains only minimal amounts, with less than 2% of the Daily Value per cup (125 grams) (2, 3).

However, unbleached, unrefined, whole-wheat varieties may be richer in several important nutrients.

In particular, whole-wheat flour packs more fiber, vitamin E, manganese, copper, and antioxidants (4).

Both bleached and unbleached flours are also often enriched with B vitamins like folate, niacin, vitamin B6, and thiamine (1).

Summary

Bleached and unbleached white flours are nearly identical in terms of nutrition. Other varieties of unbleached flour, such as whole-wheat flour, may contain more fiber, vitamin E, manganese, copper, and antioxidants.

Bleached flour is treated with several chemical agents to help speed up the aging process.

The safety of these chemicals has often been called into question.

For example, potassium bromate, which is a common additive used in bread-making, has been linked to kidney damage and cancer in some animal studies (5, 6, 7, 8).

Though it’s illegal in the European Union, Canada, Brazil, Argentina, and Nigeria, it remains legal and widely used in the United States.

Benzoyl peroxide is another common food additive that is generally recognized as safe by the Food and Drug Administration (FDA) (9).

Still, some test-tube and animal studies have found that it may harm your antioxidant status and break down certain nutrients in foods, including essential fatty acids (10, 11).

Keep in mind that most current research is limited to animal and test-tube studies using very high doses of these chemical compounds.

Therefore, more studies in humans are needed to evaluate the safety of bleached flour when consumed in normal amounts.

Summary

Some chemical compounds in bleached flour have been linked to adverse effects in animal and test-tube studies. More research in humans is needed to evaluate the safety of these bleaching agents.

Due to their variations in texture, each type of flour may be better-suited for certain recipes.

Bleached flour has a finer grain and absorbs more liquid, which works well for foods like cookies, pancakes, waffles, quick breads, and pie crusts.

Meanwhile, the denser texture of unbleached flour can help baked goods hold their shape a bit better, making it a good fit for puff pastries, eclairs, yeast breads, and popovers.

That said, both types can be used interchangeably in most baked goods without significantly altering the final product or needing to adjust other ingredients in your recipe.

Summary

Bleached flour works well in recipes like cookies, pancakes, waffles, quick breads, and pie crusts. Meanwhile, unbleached flour is better suited for puff pastries, eclairs, yeast breads, and popovers.

Bleached flour is treated with chemicals to speed up the aging process, whereas unbleached flour is aged naturally.

Both types also differ in texture, appearance, and potential uses.

Opting for unbleached, whole-wheat flour may increase your intake of several nutrients and minimize your exposure to potentially harmful chemicals.

Still, both varieties can be used interchangeably in most recipes without significantly altering the final product.