All about flour - differences between different types of flour, nutritional value and benefits

Flour is one of the most common food products, which is obtained by grinding cereal grains and grains of other crops suitable for the preparation of bakery, pasta, confectionery and other products. What are the benefits and harms of wheat flour? What types of flour are there? How to choose quality flour? Read our material.

Flour is a product made from ground grain. The main types of baking flour are wheat and rye. Wheat flour is more popular and is produced more than rye flour.

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Where did it all start? Who came up with the idea of grinding wheat and why?

Agree, today it is difficult to imagine that humanity used to do without flour.

For many years, there was only one data - flour began to be made during the Neolithic period. Scientists assumed that flour was invented by ancient people from the Middle East, who previously ground acorns and nuts instead of wheat.

About 10,000 years ago, Neolithic man first began to eat raw cereal grains. People understood that grains were nutritious and tasty. Ancient people noticed that even more grains could grow from grains planted in the ground.

So, people began to settle in the place where they found food. By this time, people had already learned to make fire and use it not only as a source of heat, but also as a method of cooking.

An ancient man suddenly discovered that dried grains were much easier to peel from the ear. This meant that the heated grains could be easily crushed with a stone and water added, which would result in a kind of liquid gruel. This is what the first bread originally looked like.

And at that time, grain powder became very popular. Further, they began to make bread more similar to today. In ancient times, they began to make unleavened flatbreads from fashion and flour and baked it all over a fire. Well, much later, they came up with a mill mechanism.

Important: 100 gr. premium wheat flour contain - carbohydrates 68.9 g, proteins 10.3 g, fats 1.10 g. Energy value 334 kcal.

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Vitamins in wheat flour

Wheat flour contains the following vitamins: Mono- and disaccharides, SFA - Saturated fatty acids, PUFA - Polyunsaturated fatty acids, Ash, Starch, Water, Dietary fiber, Sodium, Potassium, Phosphorus, Magnesium, Calcium, Sulfur, Copper, Boron, Silicon, Aluminum, Titanium, Iodine, Manganese, Chromium, Fluorine, Molybdenum, Vanadium, Cobalt, Nickel, Selenium, Tin, Zinc, Iron, Chlorine.

Vitamin	Meaning
Vitamin B1 (thiamine), mg	0,17
Vitamin B2 (riboflavin), mg	0,04
Vitamin B6 (pyridoxine), mg	0,17
Vitamin B9 (folic), mcg	27,1
Vitamin E (TE), mg	1,5
Vitamin PP (Niacin equivalent), mg	3
Choline, mg	52
Vitamin B5 (pantothenic), mg	0,3
Vitamin H (biotin), mcg	2

Product	Kcal	Proteins, g	Fats, g	Angle, g
White Wheat Flour (Confectionery)	364	10,33	0,98	76,31
Whole Wheat Flour	339	13,7	1,87	72,57
Wheat flour	334	10,8	1,3	69,9
Premium wheat flour	334	10,8	1,3	69,9
First grade wheat flour	329	11,1	1,5	67,8
Second grade wheat flour	324	11,7	1,81	63,7
Wallpaper wheat flour	312	11,5	2,2	61,5
Wheat germ flour	335	33,87	7,7	32,7
Wheat flour	339	13,7	1,87	60,37
Premium wheat flour (purchased), 10% protein, unbleached, enriched	366	9,71	1,48	73,82
Premium wheat flour (purchased), 10% protein, bleached, unfortified	366	9,71	1,48	73,82
Premium wheat flour (purchased), 10% protein, bleached, enriched	366	9,71	1,48	73,82
Premium wheat flour (purchased), 11.5% protein, unbleached, enriched	363	11,5	1,45	71,41
Premium wheat flour (purchased), 11.5% protein, bleached, unfortified	363	11,5	1,45	71,41
Premium wheat flour (purchased), 11.5% protein, bleached, enriched	363	11,5	1,45	73,81
Premium wheat flour (purchased), 13% protein, bleached, unfortified	362	13,07	1,38	69,8
Premium wheat flour (purchased), 13% protein, bleached, enriched	362	13,07	1,38	69,8
Premium wheat flour (purchased), 15% protein, bleached, unfortified	362	15,33	1,41	67,48
Premium wheat flour (purchased), 15% protein, bleached, enriched	362	15,33	1,41	67,48
Premium wheat flour (purchased), 9% protein, bleached, unfortified	367	8,89	1,43	74,92
Premium wheat flour (purchased), 9% protein, bleached, enriched	367	8,89	1,43	77,32
Premium quality wheat flour, confectionery, enriched	362	8,2	0,86	76,33
Premium wheat flour, tortilla mix, enriched	405	9,66	10,63	67,14
Premium wheat flour, all-purpose, unfortified	364	10,33	0,98	76,31
Premium quality wheat flour, all-purpose, enriched with calcium	364	10,33	0,98	73,61
Premium wheat flour, all-purpose, enriched, unbleached	364	10,33	0,98	76,31
Premium wheat flour, all-purpose, enriched, bleached	364	10,33	0,98	73,61
Premium wheat flour, all-purpose, enriched, self-raising	354	9,89	0,97	74,22
Premium quality wheat flour, baking, enriched	361	11,98	1,66	70,13
Wheat flour, baking, unfortified	361	11,98	1,66	70,13
Premium flour from soft wheat varieties	334	10,3	1,1	70,6
Wheat flour, second grade	324	11,7	1,81	63,7
Wheat flour, premium	334	10,8	1,3	69,9
Wheat flour, premium, fortified	334	10,3	1,1	68,9
Wheat flour, wallpaper	312	11,5	2,2	61,5
Wheat flour, first grade	329	11,1	1,5	67,8
Wheat flour, first grade, fortified	331	10,6	1,3	67,6

We suggest you familiarize yourself with what premium flour is made from

What flour is used for what?

Sometimes you want to replace traditional wheat flour with something original. I am tormented by doubts, because there is a great choice: chestnut flour, buckwheat, corn and so on and so forth...

Whole grain flour is obtained from whole grains and is used for baking bread with bran. This flour contains the highest ratio of ash substances and a high percentage of minerals concentrated in the grain shell. First of all, it is phosphorus, potassium, magnesium, sulfur. The higher this percentage, the darker and coarser the flour.

The shell, which has invaluable nutritional qualities, is preserved. It is only important that such flour be obtained from organic grain, because it is in the shell that harmful substances are concentrated - pesticides, for example. Whole grain flour is indispensable for a healthy diet. Bread with bran is baked from it.

Wallpaper flour is cleaner: the fruit membranes are partially removed, a small amount of bran is selected. However, it also contains a huge amount of useful substances and minerals.

Sieve flour , or paklevanny - finely ground sifted flour. It is perfect for baking bread and pies. Products made from such flour are rich in fiber and nutrients and can also be stored for a long time.

Bleached flour is intended for all types of home baking. It is ideal for white bread, pita, pizza. The highest quality of bleached flour is designated by the word “extra”. It makes perfect pastries and cakes.

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Chemical composition of flour

The chemical composition of flour determines its nutritional value and baking properties. The chemical composition of flour depends on the composition of the grain from which it is obtained and the type of flour. Higher grades of flour are obtained from the central layers of the endosperm, so they contain more starch and less proteins, sugars, fat, minerals, vitamins, which are concentrated in its peripheral parts. The average chemical composition of wheat and rye flour is presented in Table 10.

Table 10 Chemical composition of flour, in % on dry matter.

Both wheat and rye flour contain the most carbohydrates (starch, mono- and disaccharides, pentosans, cellulose) and proteins, the properties of which determine the properties of the dough and the quality of bread.

Carbohydrates.

Flour contains a variety of carbohydrates: simple sugars, or monosaccharides (glucose, fructose, arabinose, galactose); disaccharides (sucrose, maltose, raffinose); starch, cellulose, hemicelluloses, pentosans.

Starch

- the most important carbohydrate of flour, contained in the form of grains ranging in size from 0.002 to 0.15 mm. The size and shape of starch grains are different for different types and grades of flour. The starch grain consists of amylose, which forms the inner part of the starch grain, and amylopectin, which makes up its outer part. The quantitative ratios of amylose and amylopectin in the starch of various cereals are 1:3 or 1:3.5. Amylose differs from amylopectin in having a lower molecular weight and a simpler molecular structure. The amylose molecule consists of 300-8000 glucose residues forming straight chains. The amylopectin molecule has a branched structure and contains up to 6000 glucose residues. In hot water, amylopectin swells and amylose dissolves.

In the process of making bread, starch performs the following functions:

is a source of fermentable carbohydrates in dough, undergoing hydrolysis under the action of amylolytic enzymes (a- and p-amylases);
absorbs water during kneading, participating in the formation of dough;
gelatinizes during baking, absorbing water and participating in the formation of bread crumb;
is responsible for the staleness of bread during storage.

The process of swelling of starch grains in hot water is called gelatinization. At the same time, starch grains increase in volume, become more loose and are easily susceptible to the action of amylolytic enzymes. Wheat starch gelatinizes at a temperature of 62-65° C, rye starch - 50-55° C.

The starch state of flour affects the properties of the dough and the quality of bread. The size and integrity of starch grains affect the consistency of the dough, its water absorption capacity and its sugar content. Small and damaged starch grains are able to bind more moisture in the dough and are easily susceptible to the action of enzymes during the dough preparation process than large and dense grains.

The structure of starch grains is crystalline, finely porous. Starch has a high ability to bind water. When baking bread, starch binds up to 80% of the moisture in the dough. When storing bread, the starch paste undergoes “aging” (sy-neresis), which is the main reason for bread going stale.

Cellulose, hemicelluloses, pentosans

belongs to the group of dietary fibers. Dietary fiber is found mainly in the peripheral parts of the grain and therefore is most abundant in high-yield flour. Dietary fiber is not absorbed by the human body, so it reduces the energy value of flour, while increasing the nutritional value of flour and bread, since it accelerates intestinal motility, normalizes lipid and carbohydrate metabolism in the body, and promotes the elimination of heavy metals.

Pentosans

Flour can be soluble or insoluble in water.

Some flour pentosans can easily swell and dissolve in water (peptize), forming a very viscous mucus-like solution.

Therefore, water-soluble flour pentosans are often called mucilages. It is mucus that has the greatest influence on the rheological properties of wheat and rye dough. Of the total amount of pentosans in wheat flour, only 20-24% are water-soluble. Rye flour contains more water-soluble pentosans (about 40%). Pentosans, which are insoluble in water, swell intensely in dough, binding a significant amount of water.

Fats

are esters of glycerol and higher fatty acids. The composition of flour fats includes mainly liquid unsaturated acids (oleic, linoleic and linolenic). The fat content in different types of wheat and rye flour is 0.8-2.0% on a dry matter basis. The lower the grade of flour, the higher the fat content in it.

Fat-like substances include phospholipids, pigments and some vitamins. These substances are called fat-like because they, like fats, do not dissolve in water, but are soluble in organic solvents.

Phospholipids have a structure similar to fats, but in addition to glycerol and fatty acids, they also contain phosphoric acid and nitrogenous substances. Flour contains 0.4-0.7% phospholipids. Flour coloring agents (pigments) consist of chlorophyll and carotenoids. Chlorophyll contained in the shells is a green substance, carotenoids are yellow and orange in color. When oxidized, carotenoid pigments become discolored. This property manifests itself during storage of flour, which lightens as a result of the oxidation of carotenoid pigments by atmospheric oxygen.

Chemical composition of flour

The chemical composition of flour depends on the composition of the grain from which it is made and on its variety.
The higher the grade of flour, the more starch it contains. The content of other carbohydrates, as well as fat, ash, proteins and other substances increases with decreasing grade of flour. Features of the quantitative and qualitative composition of flour determine its nutritional value and baking properties. Nitrogenous and proteinaceous substances The nitrogenous substances
of flour mainly consist of proteins.
Non-protein nitrogenous substances (amino acids, amides, etc.) are contained in small quantities (2-3% of the total mass of nitrogenous compounds). The higher the flour yield, the more nitrogenous substances and non-protein nitrogen it contains. Wheat flour proteins. Flour is dominated by simple proteins—proteins. Flour proteins have the following fractional composition (in%): prolamines 35.6; glutelins 28.2; globulins 12.6; albumins 5.2. The average content of protein substances in wheat flour is 13-16%, insoluble protein 8.7%. Prolamins and glutelins of various cereals have their own characteristics in amino acid composition, different physicochemical properties and different names. The prolamins of wheat and rye are called gliadins, the prolamins of barley are called hordein, the prolamins of corn are called zein, and the glutelin of wheat is called glutenin. It should be borne in mind that albumins, globulins, prolamins and glutelins are not individual proteins, but only protein fractions released by various solvents. The technological role of flour proteins in the preparation of bread products is very great. The structure of protein molecules and the physicochemical properties of proteins determine the rheological properties of the dough and affect the shape and quality of products. The nature of the secondary and tertiary structure of the protein molecule, as well as the technological properties of flour proteins, especially wheat, largely depend on the ratio of disulfide and sulfhydryl groups. When kneading dough and other semi-finished products, proteins swell, adsorbing most of the moisture. The proteins of wheat and rye flour are more hydrophilic, capable of absorbing up to 300% of their weight in water. The optimal temperature for swelling of gluten proteins is 30 °C. Gliadin and glutelin fractions of gluten, isolated separately, differ in structural and mechanical properties. The mass of hydrated glutelin is short-extensible and elastic; The mass of gliadin is liquid, viscous, lacking elasticity. Gluten formed by these proteins includes the structural and mechanical properties of both fractions. When baking bread, protein substances undergo heat denaturation, forming a strong framework of bread. The average content of raw gluten in wheat flour is 20-30%. In different batches of flour, the raw gluten content varies. within a wide range (16-35%). Gluten composition. Raw gluten contains 30-35% dry matter and 65-70% moisture. Gluten dry matter is 80-85% composed of proteins and various flour substances (lipids, carbohydrates, etc.), with which gliadin and glutenin react. Gluten proteins bind about half of the total amount of flour lipids. Gluten protein contains 19 amino acids. Glutamic acid (about 39%), proline (14%) and leucine (8%) predominate. Gluten of different qualities has the same amino acid composition, but a different molecular structure. The rheological properties of gluten (elasticity, elasticity, extensibility) largely determine the baking properties of wheat flour. There is a widespread theory about the importance of disulfide bonds in a protein molecule: the more disulfide bonds appear in a protein molecule, the higher the elasticity and lower the extensibility of gluten. Weak gluten has fewer disulfide and hydrogen bonds than strong gluten. Rye flour proteins. In terms of amino acid composition and properties, rye flour proteins differ from wheat flour proteins. Rye flour contains a lot of water-soluble proteins (about 36% of the total mass of protein substances) and salt-soluble proteins (about 20%). The prolamine and glutelin fractions of rye flour are significantly lower in weight; under normal conditions they do not form gluten. The total protein content in rye flour is slightly lower than in wheat flour (10-14%). Under special conditions, a protein mass can be isolated from rye flour, which resembles gluten in elasticity and extensibility. The hydrophilic properties of rye proteins are specific. They quickly swell when flour is mixed with water, and a significant part of them swells unlimitedly (peptizes), turning into a colloidal solution. The nutritional value of rye flour proteins is higher than that of wheat proteins, since they contain more essential amino acids, especially lysine. Carbohydrates
The carbohydrate complex of flour is dominated by higher polysaccharides (starch, fiber, hemicellulose, pentosans).
Flour contains small amounts of sugar-like polysaccharides (di- and trisaccharides) and simple sugars (glucose, fructose). Starch. Starch is the most important carbohydrate of flour, contained in the form of grains ranging in size from 0.002 to 0.15 mm. The size, shape, ability to swell and gelatinize starch grains are different for different types of flour. The size and integrity of starch grains affects the consistency of the dough, its moisture capacity and sugar content. Small and damaged starch grains are saccharified faster during the bread making process than large and dense grains. Starch grains, in addition to starch itself, contain small amounts of phosphoric, silicic and fatty acids, as well as other substances. The structure of starch grains is crystalline, finely porous. Starch is characterized by significant adsorption capacity, as a result of which it can bind large amounts of water even at a temperature of 30 ° C, i.e. at the temperature of the dough. The starch grain is heterogeneous; it consists of two polysaccharides: amylose, which forms the inner part of the starch grain, and amylopectin, which makes up its outer part. The quantitative ratios of amylose and amylopectin in the starch of various cereals are 1: 3 or 1: 3.5. Amylose differs from amylopectin in having a lower molecular weight and a simpler molecular structure. The amylose molecule consists of 300-800 glucose residues forming straight chains. Amylopectin molecules have a branched structure and contain up to 6000 glucose residues. When starch is heated with water, amylose goes into a colloidal solution, and amylopectin swells, forming a paste. Complete gelatinization of flour starch, during which its grains lose their shape, is carried out at a ratio of starch and water of 1: 10. Undergoing gelatinization, starch grains significantly increase in volume, become loose and more pliable to the action of enzymes. The temperature at which the viscosity of starch jelly is greatest is called the starch gelatinization temperature. The gelatinization temperature depends on the nature of the starch and on a number of external factors: the pH of the medium, the presence of electrolytes in the medium, etc. The gelatinization temperature, viscosity and rate of aging of the starch paste are not the same for different types of starch. Rye starch gelatinizes at a temperature of 50-55 °C, wheat starch at 62-65 °C, corn starch at 69-70 °C. Such features of starch are of great importance for the quality of bread. The presence of table salt significantly increases the gelatinization temperature of starch. The technological significance of flour starch in bread production is very great. The condition of starch grains largely determines the water absorption capacity of the dough, its fermentation processes, the structure of the bread crumb, taste, aroma, porosity of bread, and the rate of staling of products. When kneading dough, starch grains bind a significant amount of moisture. The water absorption capacity of mechanically damaged and small starch grains is especially high, since they have a large specific surface area. During the process of fermentation and proofing of the dough, part of the starch is saccharified under the action of 3-amylase, turning into maltose. The formation of maltose is necessary for normal dough fermentation and bread quality. When baking bread, starch gelatinizes, binding up to 80% of the moisture in the dough, which ensures the formation of a dry, elastic bread crumb. During storage of bread, the starch paste undergoes aging (syneresis), which is the main reason for the staling of bread products. Cellulose
.
Fiber (cellulose) is found in the peripheral parts of the grain and is therefore found in large quantities in high-yield flour. Wallpaper flour contains about 2.3% fiber, and premium wheat flour contains 0.1-0.15%. Fiber is not absorbed by the human body and reduces the nutritional value of flour. In some cases, a high fiber content is beneficial, as it accelerates intestinal motility. Hemicelluloses
.
These are polysaccharides belonging to pentosans and hexosans. In terms of physicochemical properties, they occupy an intermediate position between starch and fiber. However, hemicelluloses are not absorbed by the human body. Wheat flour, depending on the variety, has a different content of pentosans - the main component of hemicellulose. High-grade flour contains 2.6% of the total amount of grain pentosans, and II-grade flour contains 25.5%. Pentosans are divided into soluble and insoluble. Insoluble pentosans swell well in water, absorbing water in quantities 10 times their mass. Soluble pentosans or carbohydrate mucilages produce very viscous solutions, which, under the influence of oxidizing agents, turn into dense gels. Wheat flour contains 1.8-2% mucus, rye flour - almost twice as much. Lipids
Lipids are fats and fat-like substances (lipoids).
All lipids are insoluble in water and soluble in organic solvents. The total lipid content in whole wheat grain is about 2.7%, and in wheat flour 1.6-2%. In flour, lipids are found both in a free state and in the form of complexes with proteins (lipoproteins) and carbohydrates (glycolipids). Recent studies have shown that lipids associated with gluten proteins significantly influence its physical properties. Fats. Fats are esters of glycerol and high molecular weight fatty acids. Wheat and rye flour of various varieties contains 1-2% fat. The fat in flour has a liquid consistency. It consists mainly of glycerides of unsaturated fatty acids: oleic, linoleic (mainly) and linolenic. These acids have high nutritional value and are credited with vitamin properties. Hydrolysis of fat during flour storage and further transformations of free fatty acids significantly affect the acidity, taste of flour and the properties of gluten. Lipoids. Flour lipoids include phosphatides - esters of glycerol and fatty acids containing phosphoric acid combined with some nitrogenous base. Flour contains 0.4-0.7% phosphatides belonging to the group of lecithins, in which the nitrogenous base is choline. Lecithins and other phosphatides are characterized by high nutritional value and have great biological significance. They easily form compounds with proteins (lipoprotein complexes), which play an important role in the life of every cell. Lecithins are hydrophilic colloids that swell well in water. Being surfactants, lecithins are also good food emulsifiers and bread improvers. Pigments
.
Fat-soluble pigments include carotenoids and chlorophyll. The color of carotenoid pigments in flour is yellow or orange, and chlorophyll is green. Carotenoids have provitamin properties, since they are capable of being converted into vitamin A in the animal body. The most well-known carotenoids are unsaturated hydrocarbons. When oxidized or reduced, carotenoid pigments turn into colorless substances. The process of bleaching high-quality wheat flour, used in some foreign countries, is based on this property. In many countries, bleaching flour is prohibited as it reduces its vitamin value. The fat-soluble vitamin of flour is vitamin E; other vitamins of this group are practically absent in flour. Minerals
Flour consists mainly of organic substances and a small amount of mineral (ash).
The minerals of the grain are concentrated mainly in the aleurone layer, shells and embryo. There are especially many minerals in the aleurone layer. The content of mineral substances in the endosperm is low (0.3-0.5%) and increases from the center to the periphery, therefore the ash content serves as an indicator of the type of flour. Most of the minerals in flour consist of phosphorus compounds (50%), as well as potassium (30%), magnesium and calcium (15%). Various microelements (copper, manganese, zinc, etc.) are contained in minute quantities. The iron content in the ash of different types of flour is 0.18-0.26%. A significant proportion of phosphorus (50-70%) is presented in the form of phytin - (Ca - Mg - salt of inositol phosphoric acid). The higher the grade of flour, the less minerals it contains. Enzymes
Cereal grains contain a variety of enzymes, concentrated mainly in the germ and peripheral parts of the grain. Because of this, flour with high yields of enzymes contains more enzymes than flour with low yields. The enzyme activity of different batches of flour of the same type is different. It depends on the growing conditions, storage, drying and conditioning conditions of the grain before grinding. Increased enzyme activity was observed in flour obtained from unripe, sprouted, frost-damaged or bug-infected grain. Drying grain under severe conditions reduces the activity of enzymes; when storing flour (or grain), it also decreases somewhat. Enzymes are active only with sufficient environmental humidity, therefore, when storing flour with a moisture content of 14.5% or lower, the effect of enzymes is very weak. After kneading, enzymatic reactions begin in semi-finished products, in which hydrolytic and redox enzymes of flour participate. Hydrolytic enzymes (hydrolases) decompose the complex substances of flour into simpler water-soluble hydrolysis products. It has been noted that proteolysis in wheat dough is activated by substances containing sulfhydryl groups and other substances with reducing properties (amino acid cysteine, sodium thiosulfate, etc.). Substances with opposite properties (with oxidizing properties) significantly inhibit proteolysis, strengthen gluten and the consistency of wheat dough. These include calcium peroxide, potassium bromate and many other oxidizing agents. The effect of oxidizing agents and reducing agents on the process of proteolysis is already evident at very small dosages of these substances (hundredths and thousandths of a percent of the flour weight). There is a theory that the effect of oxidizing agents and reducing agents on proteolysis is explained by the fact that they change the ratio of sulfhydryl groups and disulfide bonds in the protein molecule, and possibly the enzyme itself. Under the influence of oxidizing agents, groups form disulfide bonds that strengthen the structure of the protein molecule. Reducing agents break these bonds, which causes the gluten and wheat dough to weaken. The chemistry of the action of oxidizing agents and reducing agents on proteolysis has not been fully established. The autolytic activity of wheat and especially rye flour is the most important indicator of its baking properties. Autolytic processes in semi-finished products during fermentation, proofing and baking must occur with a certain intensity. With increased or decreased autolytic activity of flour, the rheological properties of the dough and the nature of fermentation of semi-finished products change for the worse, and various bread defects arise. In order to regulate autolytic processes, it is necessary to know the properties of the most important flour enzymes. The main hydrolytic enzymes of flour include proteolytic and amylolytic enzymes. Proteolytic enzymes. They act on proteins and their hydrolysis products. The most important group of proteolytic enzymes is proteinases. Proteinases such as papain are found in grains and flours of various cereals. The optimal parameters for the action of grain proteinases are pH 4-5.5 and temperature 45-47 ° C. During dough fermentation, grain proteinases cause partial proteolysis of proteins. The intensity of proteolysis depends on the activity of proteinases and on the pliability of proteins to the action of enzymes. Proteinases of flour obtained from grain of normal quality are little active. Increased activity of proteinases is observed in flour prepared from sprouted grains and especially from grains affected by the turtle bug. The saliva of this pest contains strong proteolytic enzymes that penetrate into the grain when bitten. During fermentation in dough made from normal quality flour, the initial stage of proteolysis occurs without noticeable accumulation of water-soluble nitrogen. During the preparation of wheat bread, proteolytic processes are regulated by changing the temperature and acidity of semi-finished products and adding oxidizing agents. Proteolysis is somewhat inhibited by table salt. Amylolytic enzymes. These are p- and a-amylases. p-Amylase was found both in sprouted cereal grains and in grains of normal quality; a-amylase is found only in sprouted grains. However, a noticeable amount of active a-amylase was found in rye grain (flour) of normal quality. α-Amylase is a metalloprotein; its molecule contains calcium, p- and a-amylases are found in flour mainly in a state associated with protein substances and are broken down after proteolysis. Both amylases hydrolyze starch and dextrins. Mechanically damaged starch grains, as well as gelatinized starch, are most easily decomposed by amylases. The work of I.V. Glazunov established that during the saccharification of dextrins with p-amylase, 335 times more maltose is formed than during the saccharification of starch. Native starch is hydrolyzed by p-amylase very slowly. p-Amylase, acting on amylose, converts it completely into maltose. When exposed to amylopectin, p-amylase cleaves maltose only from the free ends of the glucoside chains, causing hydrolysis of 50-54% of the amount of amylopectin. High-molecular dextrins formed in this way retain the hydrophilic properties of starch. α-Amylase cleaves off the branches of the glucosidic chains of amylopectin, converting it into low-molecular dextrins that are not stained with iodine and lack the hydrophilic properties of starch. Therefore, under the action of a-amylase, the substrate is significantly liquefied. The dextrins are then hydrolyzed by a-amylase to maltose. The thermolability and sensitivity to the pH of the environment are different for both amylases: a-amylase, compared to 3-amylase, is more thermostable, but more sensitive to acidification of the substrate (decrease in pH). p-Amylase is most active at a pH of -4.5-4, 6 and a temperature of 45-50 ° C. At a temperature of 70 ° C, p-amylase is inactivated. The optimal temperature of a-amylase is 58-60 ° C, pH 5.4-5.8. The effect of temperature on the activity of a-amylase depends on reactions of the environment. With a decrease in pH, both the temperature optimum and the inactivation temperature of a-amylase decrease. According to some researchers, flour a-amylase is inactivated during the baking process of bread at a temperature of 80-85 ° C, however, some studies show that in wheat bread a-amylase is inactivated only at a temperature of 97-98 ° C. The activity of a-amylase is significantly reduced in the presence of 2% sodium chloride or 2% calcium chloride (in an acidic environment). p-Amylase loses its activity when exposed to substances (oxidizing agents) that convert sulfhydryl groups into disulfide groups. Cysteine and other drugs with proteolytic activity activate p-amylase. Low heating of the water-flour suspension (40-50 ° C) for 30-60 minutes increases the activity of flour p-amylase by 30-40%. Heating to a temperature of 60-70 ° C reduces the activity of this enzyme. The technological significance of both amylases is different. During dough fermentation, p-amylase saccharifies some of the starch (mainly mechanically damaged grains) to form maltose. Maltose is necessary to obtain loose dough and normal quality of products made from varietal wheat flour (if sugar is not included in the product recipe). The saccharifying effect of p-amylase on starch increases significantly with gelatinization of starch, as well as in the presence of a-amylase. Dextrins formed by a-amylase are saccharified by p-amylase much more easily than starch. Under the action of both amylases, starch can be completely hydrolyzed, while one β-amylase hydrolyzes it by approximately 64%. The optimal temperature for a-amylase is created in the dough when baking bread from it. Increased a-amylase activity can lead to the formation of significant amounts of dextrins in bread crumb. Low-molecular dextrins do not bind the moisture of the crumb well, so it becomes sticky and wrinkled. The activity of a-amylase in wheat and rye flour is usually judged by the autolytic activity of the flour, determined by the falling number or by the autolytic test. In addition to amylolytic and proteolytic enzymes, other enzymes influence the properties of flour and the quality of bread: lipase, lipoxygenase, polyphenol oxidase. Lipase. Lipase breaks down flour fats during storage into glycerol and free fatty acids. In wheat grain, lipase activity is low. The higher the flour yield, the higher the relative lipase activity. The optimum action of grain lipase is at pH 8.0. Free fatty acids are the main acid-reacting substances in flour. They can undergo further transformations that affect the quality of flour - dough - bread. Lipoxygenase. Lipoxygenase refers to the redox and restoration enzymes of flour. It catalyzes oxidation with oxygen of air of some unsaturated fatty acids, turning them into hydraulic transmission. The most intensively lipoxygenase oxidizes the linoleic, arachidonic and linolenic acid, which are part of grain fat (flour). In the same way, but more slowly, lipoxygenase acts in native fats for fatty acids. The optimal parameters for the action of lipoxygenase are a temperature of 30-40 ° C and pH of the medium 5-5.5. Hydro -transsis, formed from fatty acids under the influence of lipoxygenases, themselves are strong oxidizing agents and have an appropriate effect on the properties of gluten. Lipoxygenase is found in many cereals, including in rye and wheat grains. Polyphenoloxidase (tyrosinase) catalyzes the oxidation of the amino acid of tyrosine with the formation of dark -colored substances - melanins, causing darkening of the crumb of bread from varietal flour. Polyphenoloxidase is mainly contained in flour in high outputs. In wheat flour II, there is a great activity of this enzyme than in the flour of the highest or I grade. The ability of flour to darkening in the process of processing depends not only on the activity of polyphenoloxidase, but also on the content of free tyrosine, the amount of which is slight in normal quality flour. Tyrosine is formed during hydrolysis of protein substances, so flour of sprouted grain or affected by a bug-cherepashka, where proteolysis is intensively, has a high ability to darkel (almost twice as high as that of normal flour). The acid optimum polyphenoloxidase is located in the pH zone 7-7.5, and the temperature at 40-50 ° C. At pH below 5.5 polyphenoloxidase is inactive, therefore, when processing flour that has the ability to darkel, it is recommended to increase the acidity of the dough within the necessary limits.

Gluten-free flour - its types

Gluten (gluten) and starch are the main components of grain flour. It is gluten that makes the dough elastic and makes it rise by yeast. Flour with a high gluten content is called baking flour. Flour is also made from grains that do not contain gluten - it is necessary primarily for people suffering from allergies.

Buckwheat, millet, quinoa, legumes and nuts do not contain gluten. But the flour made from them gives the taste original notes. And if you combine them with wheat flour, the dough will be fluffy and the products will be golden brown.

From soft yellow corn flour you can prepare Italian polenta, Mexican tortilla, and other tasty and healthy dishes. Corn flour should be mixed with wheat flour because it does not contain gluten.
Products made from rice flour are easy to recognize - they are almost transparent. Rice does not contain gluten, so this flour is not suitable for baking pancakes and pies. But if you add wheat flour, this mixture makes wonderful pancakes and cakes - light, soft and fluffy. Rice paper is a thin rice dough made from rice flour and water.
Rye flour is very healthy; it has long been used for baking and preparing gingerbread dough.
oatmeal mainly with oatmeal cookies. Pancakes made from this flour are good, oatmeal jelly is very useful.
Buckwheat flour is very nutritious and rich in vitamins . Grayish buckwheat flour produces delicious pancakes with a pleasant nutty taste and bitterness. Japanese soba noodles made from buckwheat flour are becoming increasingly popular.
Flour made from legumes, nuts and fruits .
Chickpea flour . First of all, its property of quickly thickening when water is added is used. Therefore, such flour is added to terrines, which do not contain eggs according to the recipe. Mix chickpea flour well into the batter.
Soy and pea flour are also used for cooking .
Pies, pancakes, and cakes made from chestnut flour . This brownish-beige flour has a unique delicate aroma. To prepare yeast dough, it is good to use a mixture of chestnut and wheat flour.

Photo: Fotolia

Wheat flour: healthy or harmful?

Some people believe that wheat flour is a very harmful product. Let's figure it out now! Previously, people adhered to only one flour production technology: whole grains were ground, then stored in a safe place, in which there was no moisture or harmful insects. But in the twentieth century, due to colossal changes in the world, the quality of products began to decline. What’s wrong with store-bought goods and is it possible to make healthy baked goods in the 21st century?

The fact is that today ordinary bread in the store has nothing in common with the bread that was made previously. In the time of our ancestors, grains were not separated into their component parts and people used only whole grain flour. In Soviet times, they prepared “bricks” and other dense baked goods.

Technology began to develop rapidly, and therefore bakers decided to increase the cost of bread. To do this, it was necessary to develop more advanced methods of preparing flour. Therefore, the grain itself was divided into several parts. To obtain the “highest grade”, only the endosperm, which contains the most starch, is used from all grains.

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Moreover, during the chemical processes of dough leavening, proteins form gluten. The more it is, the fluffier the bread turns out and the longer it is stored. You can find out about this by reading the list of ingredients of any loaf in the store.

As a result, making white flour is a very cheap process, it began to spread quickly and displaced whole grain and rye flour from store shelves.

As manufacturers began to process grains in tons, this required a modern method of storing goods. As a result, we get bread that doesn’t change at all on the shelf over the course of a year: it doesn’t get damp for a long time, and insects don’t grow in it. In addition to this, some brands contain pesticides in flour. It turns out that even if you set out to cook something yourself, in the end the product will still be of dubious quality.

It is impossible not to note the high calorie content of wheat flour. This product should be consumed in limited quantities by people who are overweight or have diabetes.

To ensure that products made from wheat flour do not harm your figure, use the principle of all Italians - “for 1 tooth”. Flour products should not exceed more than 10-15% in the diet.

Premium white flour. What is the harm of premium flour?

— 7584

Probably, the production of white flour has long consisted not only in its simple grinding. Here it’s probably worth making a small “lyrical” digression and telling you, dear readers, about the structure of a grain of wheat. So, a grain of wheat consists of: an embryo - this is precisely the part from which the plant itself appears, a starchy endosperm - which feeds the embryo during germination, and three layers of protective shells (they are known by another name - bran).

The most valuable and most delicious thing in a grain is in the embryo. And now I just need to make an excursion into history. Previously, the process of grinding grain consisted of simply grinding it in stone millstones. Bread rich in vitamins B and E was baked from the resulting brown flour. But at the beginning of the 19th century, one Frenchman thought that this was terribly unprofitable. That's why he invented steel millstones. Their main difference was the ability to separate the embryo, endosperm and shell. It was from this time that the widespread persecution of people with white flour began. The embryo and shell are now fed to livestock, and the starchy endosperm is used to bake white bread. Just listen to how much we love our cattle, what healthy product we feed them. So, the germ and the shell. They contain enzymes, minerals and vitamins, as well as iron, cobalt, copper, magnesium and molybdenum, specifically wheat germ contains a full complex of vitamin B. But that's not all, whole grains contain traces of barium and vanadium (necessary for normal heart function ). The barbaric separation of the most valuable components from the starchy endosperm does not end the production of white flour (not too white). Like everything living and natural, the germ and shell interfere with long-term storage of flour. All that remains of whole grains is starch. It has no nutritional value. In order to somehow make this product valuable, synthetic vitamins are added to it, which should replace the removed natural B vitamins. There seems to be no difference - the same chemical formula, but they are produced artificially. Synthetic vitamins cannot be absorbed by the body, because they have a completely different nature. At the very beginning, nitrogen trichloride and a certain toxic substance that negatively affects the central nervous system were used to bleach flour. But this is all in the past; since 1949, chlorine dioxide, benzoyl peroxide, potassium bromate, ammonium persulfate and even alloxan have been used to bleach flour. Just the names make it creepy... This is exactly the harm of white bread that people prefer to remain silent about. Oddly enough, this production of white flour made it possible to make huge profits. Is people’s health the work of the people themselves, or is it about drowning people? The next time you buy products made from white flour, and even flour itself for home baking, remember my lines and think, do you need it?

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Wheat flour - benefits

In fact, whole wheat flour can be a healthy food product. The germ of the grain contains a lot of fats, mineral salts and healthy vitamins, and the fruit shell is a source of fiber, which is very beneficial for the human body.

Natural bread made from whole grain flour contains less vegetable protein. Flour should be stored for several days in a cool place.

High quality flour has beneficial properties for the body. Wheat flour effectively stimulates the formation of blood cells.

Flour contains the necessary components:

B vitamins (thiamine, pyridoxine, folic acid);
vitamin PP;
manganese (203% DV);
selenium (112% DV).

Let's consider the features of the quantitative and qualitative composition of flour. They determine its nutritional value and baking properties.

Nitrogenous and protein substances. The nitrogenous substances in flour mainly consist of proteins. Non-protein nitrogenous substances (amino acids, amides, etc.) are contained in small quantities (2-3% of the total mass of nitrogenous compounds). The higher the flour yield, the more nitrogenous substances and non-protein nitrogen it contains.

Wheat flour proteins. Flour is dominated by simple proteins—proteins. Flour proteins have the following fractional composition (in%): prolamines 35.6; glutelins 28.2; globulins 12.6; albumins 5.2. The average content of protein substances in wheat flour is 13-16%, insoluble protein 8.7%.

The average content of raw gluten in wheat flour is 20-30%. In different batches of flour, the raw gluten content varies. within a wide range (16-35%).

Gluten composition. Raw gluten contains 30-35% dry matter and 65-70% moisture. Gluten dry matter is 80-85% composed of proteins and various flour substances (lipids, carbohydrates, etc.), with which gliadin and glutenin react. Gluten proteins bind about half of the total amount of flour lipids. Gluten protein contains 19 amino acids. Glutamic acid (about 39%), proline (14%) and leucine (8%) predominate. Gluten of different qualities has the same amino acid composition, but a different molecular structure. The rheological properties of gluten (elasticity, elasticity, extensibility) largely determine the baking properties of wheat flour.

Rye flour proteins. In terms of amino acid composition and properties, rye flour proteins differ from wheat flour proteins. Rye flour contains a lot of water-soluble proteins (about 36% of the total mass of protein substances) and salt-soluble proteins (about 20%). The prolamine and glutelin fractions of rye flour are significantly lower in weight; under normal conditions they do not form gluten. The total protein content in rye flour is slightly lower than in wheat flour (10-14%). Under special conditions, a protein mass can be isolated from rye flour, which resembles gluten in elasticity and extensibility.

Carbohydrates. The carbohydrate complex of flour is dominated by higher polysaccharides (starch, fiber, hemicellulose, pentosans). Flour contains small amounts of sugar-like polysaccharides (di- and trisaccharides) and simple sugars (glucose, fructose).

Starch . Starch is the most important carbohydrate of flour, contained in the form of grains ranging in size from 0.002 to 0.15 mm. The size, shape, ability to swell and gelatinize starch grains are different for different types of flour. The size and integrity of starch grains affects the consistency of the dough, its moisture capacity and sugar content. Small and damaged starch grains are saccharified faster during the bread making process than large and dense grains.

Cellulose . Fiber (cellulose) is found in the peripheral parts of the grain and is therefore found in large quantities in high-yield flour. Wallpaper flour contains about 2.3% fiber, and premium wheat flour contains 0.1-0.15%. Fiber is not absorbed by the human body and reduces the nutritional value of flour. In some cases, a high fiber content is beneficial, as it accelerates intestinal motility.

Hemicelluloses . These are polysaccharides belonging to pentosans and hexosans. In terms of physicochemical properties, they occupy an intermediate position between starch and fiber. However, hemicelluloses are not absorbed by the human body. Wheat flour, depending on the variety, has a different content of pentosans - the main component of hemicellulose.

High-grade flour contains 2.6% of the total amount of grain pentosans, and II-grade flour contains 25.5%. Pentosans are divided into soluble and insoluble. Insoluble pentosans swell well in water, absorbing water in quantities 10 times their mass.

Soluble pentosans or carbohydrate mucilages produce very viscous solutions, which, under the influence of oxidizing agents, turn into dense gels. Wheat flour contains 1.8-2% mucus, rye flour - almost twice as much.

Lipids. Lipids are fats and fat-like substances (lipoids). All lipids are insoluble in water and soluble in organic solvents.

The total lipid content in whole wheat grain is about 2.7%, and in wheat flour 1.6-2%. In flour, lipids are found both in a free state and in the form of complexes with proteins (lipoproteins) and carbohydrates (glycolipids). Recent studies have shown that lipids associated with gluten proteins significantly influence its physical properties.

Fats. Fats are esters of glycerol and high molecular weight fatty acids. Wheat and rye flour of various varieties contains 1-2% fat. The fat in flour has a liquid consistency. It consists mainly of glycerides of unsaturated fatty acids: oleic, linoleic (mainly) and linolenic. These acids have high nutritional value and are credited with vitamin properties. Hydrolysis of fat during flour storage and further transformations of free fatty acids significantly affect the acidity, taste of flour and the properties of gluten.

Lipoids . Flour lipoids include phosphatides - esters of glycerol and fatty acids containing phosphoric acid combined with some nitrogenous base.

Flour contains 0.4-0.7% phosphatides belonging to the group of lecithins, in which the nitrogenous base is choline. Lecithins and other phosphatides are characterized by high nutritional value and have great biological significance. They easily form compounds with proteins (lipoprotein complexes), which play an important role in the life of every cell. Lecithins are hydrophilic colloids that swell well in water.

Pigments. Fat-soluble pigments include carotenoids and chlorophyll. The color of carotenoid pigments in flour is yellow or orange, and chlorophyll is green. Carotenoids have provitamin properties, as they are capable of being converted into vitamin A in the animal body.

Minerals. Flour consists mainly of organic substances and a small amount of mineral (ash). The minerals of the grain are concentrated mainly in the aleurone layer, shells and embryo. There are especially many minerals in the aleurone layer. The content of mineral substances in the endosperm is low (0.3-0.5%) and increases from the center to the periphery, therefore the ash content serves as an indicator of the type of flour.

Most of the minerals in flour consist of phosphorus compounds (50%), as well as potassium (30%), magnesium and calcium (15%).

Various microelements (copper, manganese, zinc, etc.) are contained in minute quantities. The iron content in the ash of different types of flour is 0.18-0.26%. A significant proportion of phosphorus (50-70%) is presented in the form of phytin - (Ca - Mg - salt of inositol phosphoric acid). The higher the grade of flour, the less minerals it contains.

Enzymes. Cereal grains contain a variety of enzymes, concentrated mainly in the germ and peripheral parts of the grain. Because of this, flour with high yields of enzymes contains more enzymes than flour with low yields.

The enzyme activity of different batches of flour of the same type is different. It depends on the growing conditions, storage, drying and conditioning conditions of the grain before grinding. Increased enzyme activity was observed in flour obtained from unripe, sprouted, frost-damaged or bug-infected grain. Drying grain under severe conditions reduces the activity of enzymes; when storing flour (or grain), it also decreases somewhat.

Enzymes are active only with sufficient environmental humidity, therefore, when storing flour with a moisture content of 14.5% or lower, the effect of enzymes is very weak. After kneading, enzymatic reactions begin in semi-finished products, in which hydrolytic and redox enzymes of flour participate. Hydrolytic enzymes (hydrolases) decompose the complex substances of flour into simpler water-soluble hydrolysis products.

Wholemeal flour has lower digestibility and energy value, but high biological value; it contains more vitamins and minerals.

Flour of the highest grades is poorer in useful substances, since they are concentrated mainly in the grain shells and germ, which are removed when receiving flour, but it is digested more easily and completely.

2nd grade flour is obtained from soft wheat. The color is white with a yellowish-gray tint. Flour differs in the content of 8-10% shells, flour particles are larger than in the 1st grade, and are heterogeneous in size. Gluten content - no less than 25% ash content - no more than 1.25%. Use 2nd grade flour for baking bread.

Wallpaper flour is made from soft wheat using single-grade wallpaper grinding without screening out the bran. Flour yield - 96% Color grayish-white, gluten content - 20%, ash content up to 2%. Used for baking bread.

Comparative characteristics of the nutritional value of different types of flour.

Nutritional value of flour.

Product	Weight - gr.	Squirrels	Fats	Carbohydrates	Energy
1st grade wheat flour	10.6	1.3	67.6
Wheat flour 2nd grade	11.7	1.8	63.7
Wheat flour of various grades	10.3	1.1	68.9
Wheat flour	11.5	2.2	56.8
Peeled rye flour	8.9	1.7	60.2
Rye wallpaper flour	10.7	1.9	56.8

Classification and assortment of wheat flour. In accordance with GOST R 52189-2003 Wheat flour. General technical conditions, depending on its intended use, wheat flour is divided into:

· wheat baking;

· general purpose wheat.

Wheat baking flour, depending on the whiteness or mass fraction of ash, mass fraction of raw gluten, as well as the grinding size, is divided into grades: extra, premium, coarse, first, second and wallpaper.

General purpose wheat flour, depending on whiteness or mass fraction of ash, mass fraction of raw gluten, as well as grinding size, is divided into types: M 45-23; M 55-23; MK 55-23; M 75-23; MK75-23; M 100-25; M 125-20; M 145-23.

Wheat flour can be enriched with vitamins and/or minerals according to standards approved by the Russian Ministry of Health, as well as baking improvers, including dry gluten, in accordance with the approved regulatory document.

The name of such flour is accordingly added: “vitaminized”, “enriched with minerals”, “enriched with a vitamin-mineral mixture”, “enriched with dry gluten” and other baking improvers.

Flour enriched with vitamins may contain a slight odor characteristic of vitamin B1 (thiamine). Wheat flour is produced for retail trade, confectionery and baking industries. Based on quality, it is divided into semolina, premium, 1st and 2nd grade flour, as well as wallpaper. Flour varieties differ in color, grind size, chemical composition, gluten content, baking properties and other indicators.

Cereals are obtained from glassy soft and durum wheat. Flour in the form of uniform grains of yellow-cream color; flour yield - 10%; its ash content is 0.6%; wet gluten content – 30%. Used for baking butter and pasta.

Premium flour is made from soft vitreous and semi-vitreous wheat. The flour is soft to the touch, the color is white or white with a creamy tint; flour yield - 10-15; 40%; ash content - 0.55%; wet gluten content – 28%. Used for sale to the population, production of confectionery and bakery products.

1st grade flour is obtained from soft wheat of varying glassiness. It is soft, white in color with a slight yellowish tint; yield - from 30 to 72% (depending on the grinding method); ash content - 0.75%; wet gluten content - 30%. This flour is widely used in the baking and confectionery industries, as well as for sale to the public.

2nd grade flour is produced from soft wheat. Its particles are heterogeneous in size; color white with a yellowish-grayish tint; flour yield - up to 85%; ash content - 1.25%; gluten content not less than 25%. It is used to make bread.

Wallpaper flour is obtained from soft wheat by single-grade wallpaper grinding without screening out bran, so the flour yield is high - 96%; flour particles are not uniform in size; color grayish-white; ash content - up to 2%; gluten content - 20%. Flour is used to make bread.

Wheat flour for pasta. It is obtained by special three-grade grinding of durum wheat with a high gluten content of good quality. The particles of this flour are larger than baking flour. Based on quality, pasta flour is divided into the highest (grain) and 1st (semi-grain) grades. Flour of the highest grade, cream color; ash content of flour - 0.7%; raw gluten - 28-30%. 1st grade flour is softer; Flour ash content is 1.1%, gluten content is 30-32%.

Classification and assortment of rye flour. In accordance with GOST R 52809-2007, baking rye flour, depending on quality, is divided into varieties:

· seeded;

· peeling;

· wallpaper;

· special.

Seeded flour is the highest quality grade of rye flour. It consists of finely ground endosperm of rye grain with a small admixture of particles of the aleurone layer and shells (only about 4% by weight of flour). Particle size from 20 to 200 microns. The color of the flour is white with a bluish tint. Flour is rich in starch (71-73%), sugars (4.7-5.0%), contains a significant amount of water-soluble substances and relatively little protein (8-10%) and fiber (0.3-0.4%). Ash content of flour is 0.65-0.75%.

Peeled flour differs from wallpaper in a lower content of shells and aleurone layer of grain (12-15% by weight of flour), as well as a higher degree of grinding. Particle size from 30 to 400 microns. The color of the flour is white with a gray or brownish tint. Peel flour, like wallpaper flour, is rich in water-soluble substances, but contains less protein (10-12%), more starch (66-68%). The fiber content in this flour is 0.9-1.1%, and the ash content of the flour is 1.2-1.4%.

Wallpaper flour is rye grain, ground after cleaning it from impurities and processing it on wallpapering machines. Flour is obtained by single-grade 95% grinding by passing through wire sieves 067.

Wallpaper flour consists of the same tissues as rye grain (with a slightly smaller number of fruit shells and germ) and contains, along with crushed endosperm, 20-25% of crushed shells and aleurone layer. Particle size from 30 to 600 microns. The color of the flour is white with a distinct gray, yellowish or greenish tint depending on the color of the rye grain. Flour is rich in water-soluble substances, sugar contains 12-14% protein, 60-64% starch, fiber - 2-2.5%, ash content - 1.8-1.9%.

Quality of wheat flour. The quality requirements for wheat flour are regulated by GOST 52189-2003. Wheat flour must meet the requirements of this standard and be produced in accordance with the Rules for organizing and maintaining the technological process at flour mills, approved in the prescribed manner.

Characteristics and standards for wheat flour

Indicator name	Characteristics and standards for wheat flour
Taste	Characteristic of wheat flour, without extraneous flavors, not sour, not bitter
Smell	Characteristic of wheat flour, without foreign odors, not musty, not moldy
Mass fraction of moisture[17], %, no more	15,0
Presence of mineral impurity	There should be no crunching sensation when chewing the flour.
Metallomagnetic impurity, mg per 1 kg of flour; the size of individual particles in the largest linear dimension is 0.3 mm and (or) a mass of no more than 0.4 mg, no more	3,0
Pest infestation	Not allowed
Pest contamination	Not allowed

The content of toxic elements, mycotoxins, pesticides, radionuclides in flour, contamination and contamination of flour by pests must not exceed the permissible levels established by hygienic requirements for the safety and nutritional value of food products.

Quality of rye flour. The quality requirements for wheat flour are regulated by GOST R 52809-2007.

In terms of organoleptic and physico-chemical indicators, rye flour must meet the general technical requirements specified in

Characteristics and standards for rye flour