Flour

| Ingredients  | Cereal Grain

An ingredient used in many foods, flour is a fine powder made from cereal grain or other starchy food sources. It is most commonly made from wheat, but also corn, rye, barley and rice, amongst many other grasses and even non-grain plants.

Flour is always based on the presence of starches, which are complex carbohydrates.

Usually, the word "flour" used alone refers to wheat flour, which is one of the most important foods in European and American culture. Wheat flour is the main ingredient in most types of breads and pastries. Wheat is so widely used because of an important property: when wheat flour is mixed with water, a complex protein called gluten develops. The gluten development is what gives wheat dough an elastic structure that allows it to be worked in a variety of ways, and which allows the retention of gas bubbles in an intact structure, resulting in a sponge-like texture to the final product.

Types of Flours

Wheat Flour

The vast majority of today's flour consumption is of wheat flour.

Wheat varieties are typically known as "hard" or "soft", depending on gluten content. Hard wheats are high in gluten, and soft wheats are low. Hard flour, or "bread" flour, is high in gluten and so forms a certain toughness which holds its shape well once baked. Soft flour is low in gluten and so results in a finer texture. Soft flour is usually divided into "cake" flour, which is the lowest in gluten, and "pastry" flour, which has slightly more gluten than cake flour.

In terms of the parts of the grain (the grass seed) used in flour -- the endosperm or starchy part, the oil-containing germ or protein part, and the bran or fiber part -- there are three general types of flour. "White" flour is made from the endosperm only. "Whole wheat" flour is made from the entire grain. A "germ" flour may also be made from the endosperm and germ, excluding the bran. The germ is sometimes sold by itself, as "wheatgerm".

• Whole wheat flour (or wholemeal flour) is ground from the entire wheat kernel, including the germ and the bran.

• Graham flour is a white flour with coarsely ground bran and wheatgerm mixed back in. It thus contains all three parts of the wheat kernel as whole wheat flour does, but it has a different texture.

• Cake flour, is a milled, bleached flour containing a low amount of gluten (around 7%), and therefore bakes with a fine texture.

• Pastry flour is slightly stronger (higher in gluten) than cake flour.

• All-purpose flour, (known as plain flour in Europe) is a blended white flour containing a medium amount of gluten (around 10%).

• Maida is a super-refined white flour used in Indian cuisine.

• Self-rising flour (also called "Self-raising flour") is an all-purpose flour that has a leavening agent blended into it for convenience.

Flour type numbers

In some markets, the different available flour varieties are labeled according to the ash mass ("mineral content") that remains after a sample is incinerated in a laboratory oven (typically at 550 °C or 900 °C, see international standards ISO 2171 and ICC 104/1). This is an easily verified indicator for the fraction of the whole grain remains in the flour, because the mineral content of the starchy endosperm is much lower than that of the outer parts of the grain. Flour made from all parts of the grain (extraction rate: 100%) leaves about 2 g ash or more per 100 g dry flour. Plain white flour (extraction rate: 50–60%) leaves only about 0.4 g.

• German flour type numbers (Mehltypen) indicate the amount of ash (measured in milligrams) obtained from 100 g of the dry mass of this flour. Standard wheat flours (defined in DIN 10355) range from type 405 for normal white wheat flour for baking, to strong bread flour types 550, 812, and the darker types 1050 and 1600 for wholegrain breads.
• French flour type numbers (type de farine) are a factor 10 smaller than those used in Germany, because they indicate the ash content (in milligrams) per 10 g flour. Type 55 is the standard, hard-wheat white flour for baking, including puff pastries ("pâte feuilletée"). Type 45 is often called pastry flour, and is generally from a softer wheat (this corresponds to what older French texts call "farine de gruau"). Some recipes use Type 45 for croissants, for instance, although many French bakers use Type 55 or a combination of Types 45 and 55. Types 65, 80, and 110 are strong bread flours of increasing darkness, and type 150 is a wholemeal flour.

In the United States and the United Kingdom, no numbered standardized flour types are defined, and the ash mass is only rarely given on the label by flour manufacturers. However, the legally required standard nutrition label specifies the protein content of the flour, which is also a way for comparing the extraction rates of different available flour types.

In general, as the extraction rate of the flour increases, so do both the protein and the ash content. However, as the extraction rate approaches 100% (whole meal), the protein content drops slightly, while the ash content continues to rise.

The following table shows some typical examples of how protein and ash content relate to each other in wheat flour:

Ash	Protein	Wheat flour type
		US	German	French	Italian
~0.4%	~9%	pastry flour	405	40	00
~0.55%	~11%	all-purpose flour	550	55	0
~0.8%	~14%	high gluten flour	812	80	1
~1%	~15%	first clear flour	1050	110	2
>1.5%	~13%	white whole wheat	1600	150	Farina integrale di grano tenero

This table is only a rough guideline for converting bread recipes. Since flour types are not standardized in many countries, the numbers may differ between manufacturers. Note that there is no Type 40 French flour. The closest is Type 45.

It is possible to determine ash content from some US manufacturers. However, US measurements are based on wheat with a 14% moisture content. Thus, a US flour with 0.48% ash would approximate a French Type 55. For US bakers of French pastry seeking an equivalent, for example, they could look at tables published by King Arthur Flour, showing their all-purpose flour is a close equivalent to French Type 55.

Other measurable properties of flour as used in baking can be determined using a variety of specialized instruments, such as the Farinograph.

Flours from other cereals

• Corn flour is an ambiguous term that can mean cornstarch or finely ground cornmeal. Cornmeal which has been leached with lye is called corn masa (masa harina) and is used to make tamales and corn tortillas in Mexican cooking.

• Atta is a popular flour used in South Asian cuisines, and is made by grinding whole wheat.

• 100% rye flour is used to bake the traditional sourdough breads of Germany and Scandinavia.

• Rice flour is of great importance in South-east Asian cuisines.

• Sorghum flour (jowar) is used in many parts of Africa and South Asia.

• Spelt flour is an alternative to wheat flour. Note: although some people with wheat allergies can tolerate spelt, other wheat-allergic patients have adverse reactions to spelt flour as well. Spelt also has less gluten than wheat, but it is not gluten-free.

• Other grains (cereal and non-cereal) ground into flours include amaranth, barley, buckwheat, millet, oats, quinoa, teff, and triticale.

Flours Made of Legumes, Tubers, Pulses, Etc.

• Chickpea flour (besan) is of great importance in Indian cuisine. Some other legumes ground for flour include soybeans, mung beans, yellow peas, urad dal, and fava beans.

• Flour can also be made from various various roots and tubers, including arrowroot, cassava (manioc, tapioca), potatoes, sweet potatoes, taro root; and other non-grain foodstuffs.

Flour Products

Some of the many foods made using flour are:

• bread
• pasta
• pastry
• cake

• "Supertoinette page in French on flour types". Supertoinette.com. http://www.supertoinette.com/fiche-cuisine/423/farine-de-ble.html. Retrieved 2011-10-31. 
• The author of this phrase has studied baking in France but has no online link to cite for this.