Flour

Flour is a finely ground powder made by grinding beans, grains, nuts, roots and seeds. 

Etymology: The English word flour is originally a variant of the word flower, and both the words derive from the Old French- fleur or flour, which had the literal meaning ‘blossom’ and a figurative meaning ‘the finest’. The phrase fleur de farine meant “the finest part of the meal”, since flour is obtained from elimination of unwanted and coarse matter from the grain during milling.

History: Earliest archaeological evidence for wheat seeds crushed between simple millstones to make flour dates back to 6000BC. In 1879, at the beginning of the Industrial Era, the first steam mill was erected in London. In the 1930’s, mills started to enrich flour with iron, niacin, thiamine and riboflavin. In 1940’s, folic acid was added to the list.

The many species of wheat together make up the genus Triticum; the most widely grown is common wheat (T. aestivum).

Degermed and heat-processed flour: An important problem for industrial revolution was the preservation flour. Transportation and a slow distribution system collided with natural shelf life. The reason for the limited shelf life was the fatty acids of the germ which reacts the moment it is exposed to oxygen. This occurs when grains are milled, the fatty acids oxidized and flour started to become rancid. Depending upon the climate and

Degermed and heat-processed flour: An important problem for industrial revolution was the preservation flour. Transportation and a slow distribution system collided with natural shelf life. The reason for the limited shelf life was the fatty acids of the germ which reacts the moment it is exposed to oxygen. This occurs when grains are milled, the fatty acids oxidized and flour started to become rancid. Depending upon the climate and the grain quality, this process takes six-nine months. In the late 19^thcentury, this process was too short for an industrial production and distribution cycle, therefore, removing the germ was an effective solution as without the germ, flour cannot become rancid. Degermed flour then became standard. Heat processed flour is flour where the germ is first separated from the endosperm and bran, then processed with steam or dry heat and then it is blended into the flour again.

Production: Milling of flour is accomplished by grinding grain between stones or steel wheels. Today, ‘stone ground’ usually means that the grain has been ground in a mill in which a revolving stone wheel turns over a stationery stone wheel, vertically or horizontally, with the grain in between.

Absorption: It refers to the amount of water a flour can take up and hold while being made into a simple dough, based on a predetermined standard dough consistency or stiffness. It is expressed as a percentage of the weight of flour.

Consider these facts:

·       Because starch is the largest component of flour, it absorbs most of the water. However, it absorbs only one-quarter to one-half its weight in water, so a small variation in starch content results in a small variation in absorption.

·       Pentosan gums absorb 10 to 15 times their weight in water, but because they are present in such tiny quantities, they don’t account for much variation in absorption ratios.

·       Proteins are present in significant amounts and absorb up to twice their weight in water.

Thus, variations in the absorption ratio of different flours are caused primarily by variations

in protein content. For all practical purposes, the absorption ratio of water by flour is a function of the protein content. The higher the protein content of the flour, the more water it can absorb. Obviously, this is an important consideration for bakers. They will have to adjust the water in their bread formulas if they start using flour of a different protein content.

Composition: The wheat grain is composed of 3 parts: endosperm (85%), germ (2%) and bran (14%).

1.     Starch: Flour consist of about 68% to 76% of starch. Starches are complex carbohydrates whose molecules consist of long chain of simpler sugars bound together. Most of the starches remain intact until they come in contact with water during the mixing process, then they absorb water and swell in size. Starch can absorb one-half to one-quarter of its wight in water. A very small amount of starch is broken down in sugars while milling and storage. This sugar is available as food for yeast.

2.     Protein: About 6%-18% of flour consist of protein, depending upon the variety of wheat. Protein act as binding agent that holds starch granules together in in the endosperm. About 80% of the proteins in the flour is called gliadin and glutenin (insoluble protein). These two proteins, when combined with water and mixed forms an elastic substance called gluten (soluble protein). Gluten proteins can absorb 2/3 their weight in water. Other important proteins present in white flour are enzymes, most importantly amylase, also called diastase. These enzymes break down starch into simple sugar into simple sugars, which is important for yeast fermentation. Yeast is able to ferment sugars but not starch, amylase makes fermentation process possible even in bread doughs with no added sugar.

3.     Moisture: The moisture content of flour in good condition ranges from 11% to 14%. If it becomes higher than this, the spoilage is likely to occur.

4.     Gums: Like starches, gums are forms of carbohydrates. Gums make up 2%-3% of white flour. The most important gums are called pentosans. They are significant because they have a much greater capability to absorb water than either starches or proteins. Pentosans absorb 10% to 15% of their weight in water. Even though they are in small quantities, they have an important effect on dough formation; they also serve as source of dietary fiber.

5.     Fats: Fats and fat-like substances (emulsifiers) comprise only about 1% of white flour, but it is necessary to be aware of them. First, they are important for gluten development. Second, they spoil easily giving flour an “off” flavor. For this reason, flour has a limited shelf life and should be used in a timely manner.

6.     Ash: Ash is another term for mineral content for flour. When bakers are buying flour, they look at two important numbers on flour description: the protein content and the ash content is determined by burning a sample of flour in a controlled environment. The starch and protein, when burned completely, turn to carbon dioxide gas, water vapor, and other gases, but the minerals do not burn and are left as ash. In general, the higher the ash content, the darker the flour. This is because the bran and the outer parts of the endosperm contain more minerals than the whiter, inner portions of the endosperm. Similarly, whole-grain flour is higher in ash than white flour. In conventional baking, bakers like a relatively low ash content because it makes whiter breads. Today, many artisan bakers of handmade breads look for darker flour with a higher ash content because it makes breads with a more robust wheat flavor. Ash content for wheat flours ranges from about 0.3% for white cake flour to about 1.5% for whole wheat flour.

7.     Pigments: Orange-yellow pigments called carotenoids are present in flour in tiny amounts. Because of these pigments, unbleached flour is creamy in color rather than pure white. As flour ages after it is milled, oxygen in the air bleaches some of these pigments, turning the flour somewhat whiter in color.

Today wheat is cleaned before milling, foreign matter is removed on the basis of size, shape and density. The purified endosperms (semolina) are then grounded on mat surface rolls to produce flour. Flour contains a high proportion of starches and two types of insoluble proteins in the flour- Glutenin and gliadin. When the dough is kneaded, these two proteins combine to produce gluten in the dough. Gluten provides elasticity to the dough, which in turn traps the air and gas released by yeast and forms a sponge like texture in baked breads.

Additives: The four most common additives used as bleaching/maturing agents are:

·       Potassium bromate, listed ingredient, used as a maturing agent that strengthens the gluten development. Doesn’t bleach.

·       Benzoyl Peroxide, bleaches, but does not act as a maturing agent and has no effect on gluten.

·       Ascorbic Acid (Vitamin C), listed as an ingredient, it is an indication that either the flour was matured using ascorbic acid or that a small amount is added as a dough enhancer. It is a maturing agent that strengthens gluten development but does not bleach.

·       Chlorine Gas, it is used as both a bleaching agent and maturing agent. It weakens gluten development and oxidizes starches, making it easier for the flour to absorb water and swell, resulting in thicker batters and stiffer doughs. The retarded gluten formation is desirable in cakes, cookies and biscuits as it would otherwise make them tougher and bread-like.

Some other chemicals used as flour treatment agents to modify color and baking properties:

o   Chlorine dioxide

o   Calcium peroxide

o   Atmospheric oxygen causes natural bleaching

Common preservatives used in commercial flour include:

o   Calcium Propanoate

o   Sodium benzoate

o   Tricalcium Phosphate

Cake flour in particular is nearly always chlorinated. All bleached and maturing agents (with exception of ascorbic acid) have been banned in United Kingdom. Many varieties of flour packaged specifically for commercial bakeries are still bromated. Retail bleached flour marketed to the home baker is now treated mostly with either peroxidation or chlorine gas. Current information from Pillsbury is that their varieties of bleached flour are treated both with benzoyl peroxide and chlorine gas. Gold Medal states that their bleached flour is treated either with benzoyl peroxide or chlorine gas, but no way exists to tell which process has been used when buying the flour at the grocery store.

Types of Flour:

1.     Enriched Flour: During the process of making flour nutrients are lost. Some of these nutrients may be replaced during refining – the result is enriched flour. These restored nutrients include iron and B vitamins (folic acid, riboflavin, niacin, and thiamine). Calcium may also be supplemented.

2.     Cake Flour: Cake flour is the lowest in gluten protein content (6%-7%) to produce minimal binding so that the cake crumbles easily.

3.     Pastry Flour: It has the second lowest gluten protein content (8%-9%) to hold together with a bit more strength than cakes, but still produce flaky crusts rather than hard or crisp ones.

4.     Plain or All-purpose Flour: AP Flour or Plain flour has a medium protein content (10%-12%). It has adequate protein content for many breads and pizza basses. “Plain” not only refers to the medium amount of gluten but also its lack of any added leaving agents (as in self-rising flour).

5.     Bread Flour/Strong Flour: It has a high gluten protein content (12%-14%). The increased protein binds the flour to entrap more Carbon Dioxide, released by yeast fermentation process, resulting in a stronger rise and chewier crumb. Hard spring wheat can be used to make bread flour.

6.     Hard Flour: Hard is a general term for flours with high gluten protein content (14%-16%). This flour may be used where a recipe adds ingredients that require the dough to be extra strong to hold together in their presence, or when strength is needed for constructions of bread (e.g., some centerpiece displays).

7.     Whole-wheat flour:

8.     Whole-meal flour:

9.     Gluten Flour: It is the refined gluten protein or theoretically 100% protein (practically refining never achieves 100%). It is used to strengthen the flour as needed. It is commonly added to whole grain flour recipes to overcome the tendency of high fiber content and interfere with glute development. It also helps in giving the bread better rising (gas holding) qualities and chew. For example: Adding approximately 1 tablespoon of per cup of AP flour gives the resulting mix of protein content of bread flour.

10.  Self-rising Flour: This flour is sold mixed with chemical leavening agents. The added ingredients are evenly distributed throughout the flour which aids in giving a consistent rise in baked goods by embedding small gas bubbles. This flour is generally used for making sponge cakes, scones, muffins, etc. Plain flour can be used to make a type of self-rising flour, although the flour will be coarser. Self-rising flour is typically composed of (or can be made from):

·       1 cup (125gms) AP Flour

·       1 teaspoon (3gms) baking powder

·       A pinch (1gm or less) salt

Other varieties:

1.     Atta Flour: It is a whole-grain wheat flour important in Indian & Pakistani cuisine, used for a range of breads such as Roti and Chapati. It is usually stone-ground to coarse granules which gives it a texture which is not easily found in flat breads.

2.     Maida Flour: It is a finely milled wheat flour used to make a wide variety of Indian breads such as Paratha, naan, biscuits and toast. It is generally referred to as (or confused with) All-purpose flour by Indian Chefs, but it closely relates to Cake flour. Like Cake flour, Maida flour is finely milled and has less protein than all-purpose flour.

3.     Noodle Flour: It is a special blend of flour used for making Asian-style noodles, made from wheat or rice.

4.     Semolina/ “00” Flour: It is one of the most popular flours used for making pasta , it coarsely ground flour made from a particularly hard variety of wheat called Durum. Zit is also used in making Breakfast cereals, puddings and couscous.

5.     Spelt: It is an ancient grain, a hexaploidy species of wheat. Spelt dough needs less kneading then common wheat flour dough. It has relatively less amount of protein content (6%-9%).

6.     Rye Flour: It used to make traditional sourdough breads. Most rye breads use a mix of rye and wheat flours because rye does not produce sufficient gluten. Pumpernickel (German) bread is made exclusively of rye, and contains a mixture of rye flour and rye meal.

European Flour Types:

In much of Europe, a flour grading system based on ash content is dominant. For example, the French grades T45 and T55 are white wheat flours with low ash, for breads and pastries. T65 includes high-gluten flours, and T80, T110, and T150 are whole wheat flours of increasing darkness. Other flours are included in this grading system. For example, T170 is dark rye flour.

Bread flours from European wheats are generally lower in protein than North American bread flours. Typically, they have a protein content of around 11 to 11.5%. Some North American mills have begun supplying similar flour to artisan bread bakers seeking to imitate classic European breads.

Gluten Free Flours:

When flours do not contain the protein gluten, they are suitable for people with gluten related allergies such as coeliac disease, non-celiac gluten sensitivity or wheat allergies.

1.     Acorn flour: It is made from ground acorns and can be used as a substitute for wheat flour. It was used by Native Americans and Koreans also use it to make Dotorimuk (acorn jelly, acorn starch).

2.     Almond flour: It is made from ground almonds.

3.     Amaranth Flour: It is produced from ground amaranth. It was commonly cultivated by Aztecs. (Rajgira Roti, Crackers, thickener is gravies, soups and stews)

4.     Apple Flour: It is made from milling apple pomace, the solid remains of juiced apples. (Can use in making pancakes, brownies, cakes, muffins, pies, etc., and in combination with other flours).

5.     Banana Flour: It is traditionally made from green bananas for thousands of years and is currently popular both as gluten free replacement and as a source of resistant starch (high starch content so can be used as a thickening agent). Used in making smoothies, nutrition bars, gluten free donuts/brownies).

6.     Bean Flour: This flour is used in making pulverized (reduce to fine particles) dried or ripe beans. Garbanzo (similar to chickpea) and fava bean flour is a flour mixture with a high nutritional value and strong aftertaste. Can be used as an egg substitute to make vegan omelets and quiches, use in sweet or savory baked goods or mix with gluten free flour to increase the protein content and help the products bake similar to wheat products.

7.     Brown rice flour: It is of great importance in southeast Asian cuisine. Edible rice paper can be made from it.

8.     Buckwheat flour: Used as an ingredient in making pancakes in the United States. Used in Japan to make popular noodle called Soba. In Russia. In Russia, it is added to the batter for the pan cakes called blinis which is frequently eaten with caviar. Also, on Hindu fasting days (Navratri/Maha Shivratri) people eat food made from buckwheat flour (Kuttu ka atta), dishes such as kuttu ki puri and kuttu pakora are made.

9.     Cassava flour: It is made from the root of the cassava plant. If purified (pure starch), it is called tapioca flour.

10.  Chestnut flour is popular in Corsica, the Périgord, and Lunigiana for breads, cakes and pastas. It is the original ingredient for polenta, still used as such in Corsica and other Mediterranean locations. Chestnut bread keeps fresh for as long as two weeks. In other parts of Italy it is mainly used for desserts.

11.  Chickpea flour (also known as gram flour or besan) is of great importance in Indian cuisine, and in Italy, where it is used for the Ligurian farinata.

12.  Chuño flour is made from dried potatoes in various countries of South America.

13.  Coconut flour is made from ground coconut meat and has the highest fiber content of any flour, having a very low concentration of digestible carbohydrates and thus making an excellent choice for those looking to restrict their carbohydrate intake. It also has a high fat content of about 60 percent.

14.  Coffee flour is flour usually made with either coffee cherries or coffee beans.

15.  Corn (maize) flour is popular in the Southern and Southwestern US, Mexico, Central America, and Punjab regions of India and Pakistan, where it is called makai ka atta. Coarse whole-grain corn flour is usually called corn meal. Finely ground corn flour that has been treated with food-grade lime is called masa harina (see masa) and is used to make tortillas and tamales in Mexican cooking. Corn flour should never be confused with corn starch, which is known as "corn flour" in British English.

16.  Cornmeal is very similar to corn flour (see above) except in a coarser grind.

17.  Corn starch is starch extracted from endosperm of the corn kernel.

18.  Glutinous rice flour or sticky rice flour is used in east and southeast Asian cuisines for making tangyuan, etc.

19.  Hemp flour is produced by pressing the oil from the hemp seed and milling the residue. Hemp seed is approximately 30 percent oil and 70 percent residue. Hemp flour does not rise, and is best mixed with other flours. Added to any flour by about 15-20 percent, it gives a spongy nutty texture and flavor with a green hue.

20.  Mesquite flour is made from the dried and ground pods of the mesquite tree, which grows throughout North America in arid climates. The flour has a sweet, slightly nutty flavor and can be used in a wide variety of applications.

21.  Nut flours are grated from oily nuts—most commonly almonds and hazelnuts—and are used instead of or in addition to wheat flour to produce more dry and flavorful pastries and cakes. Cakes made with nut flours are usually called tortes and most originated in Central Europe, in countries such as Hungary and Austria.

22.  Peasemeal or pea flour is a flour produced from roasted and pulverized yellow field peas.

23.  Peanut flour made from shelled cooked peanuts is a high-protein alternative to regular flour.

24.  Potato starch flour is obtained by grinding the tubers to a pulp and removing the fiber and protein by water-washing. Potato starch (flour) is very white starch powder used as a thickening agent. Standard (native) potato starch needs boiling, to thicken in water, giving a transparent gel. Because the flour is made from neither grains nor legumes, it is used as a substitute for wheat flour in cooking by Jews during Passover, when grains are not eaten.

25.  Potato flour, often confused with potato starch, is a peeled, cooked potato powder of mashed, mostly drum-dried and ground potato flakes using the whole potato and thus containing the protein and some of the fibers of the potato. It has an off-white slight yellowish color. These dehydrated, dried, potatoes, also called instant mashed potatoes can also be granules or flakes. Potato flour is cold-water-soluble; however, it is not used often as it tends to be heavy.

26.  Rice flour is ground kernels of rice. It is widely used in Western countries especially for people who suffer from gluten-related disorders. Brown rice flour has higher nutritional value than white rice flour.

27.  Sorghum flour is made from grinding whole grains of the sorghum plant. It is called jowar in India.

28.  Tapioca flour, produced from the root of the cassava plant, is used to make breads, pancakes, tapioca pudding, a savory porridge called fufu in Africa, and is used as a starch.

29.  Teff flour is made from the grain teff, and is of considerable importance in eastern Africa (particularly around the horn of Africa). Notably, it is the chief ingredient in the bread injera, an important component of Ethiopian cuisine.

More types:

List of edible seeds, Flour also can be made from soybeans, arrowroot, taro, cattails, acorns, manioc, quinoa, and other non-cereal foodstuffs.

Starches:

In addition to flours, other starch products are used in the bakeshop. Unlike flour, they are used primarily to thicken puddings, pie fillings, and similar products. The three most important starches in dessert production are as follows:

·       Cornstarch has a special property that makes it valuable for certain purposes. Products thickened with cornstarch set up almost like gelatin when cooled. For this reason, cornstarch is used to thicken cream pies and other products that must hold their shape.

·       Waxy maize is made from a different type of corn. It is almost always manufactured into a form called modified food starch. Waxy maize and other modified starches have valuable properties. Because they do not break down when frozen, they are used for products that are to be frozen. Also, they are clear when cooked and give a brilliant, clear appearance to fruit pie fillings. Waxy maize does not set up firm like cornstarch but rather makes a soft paste that has the same consistency hot and cold. Thus, it is not suitable for cream pie fillings.

·       Instant starches are precooked or pre-gelatinized so they thicken cold liquids without further cooking. They are useful when heat will damage the flavor of the product, as in fresh fruit glazes such as strawberry.

Flammability:

Flour dust suspended in air is explosive—as is any mixture of a finely powdered flammable substance with air. Some devastating explosions have occurred at flour mills, including an explosion in 1878 at the Wash burn "A" Mill in Minneapolis which killed 22 people.

Professional Baking by Wayne Gisslen (6th edition) was a major help throughout.