Flour

from Wikipedia, the free encyclopedia
Three types of flour that are used for bread.
From left: wheat flour type 550, wheat flour type 1050, rye flour type 1150

As flour (Latin farina ) primarily is powder referred to in the fine grinding of cereal grains is formed. Flour is made from the grain types wheat (also from the subspecies: spelled , emmer , einkorn ), rye , oats , barley , millet , maize and rice . Self-baking capability - ie for the production of bread suitable - are the flours from soft wheat , durum wheat , spelled and rye (bread grain). Emmer and einkorn can also be baked at home, but they hardly play a role economically. The self-baking durum wheat flour is not intended for bread baking in Germany. This article mainly describes flours made from common wheat, spelled and rye.

In addition to cereals, pseudograins (such as buckwheat or quinoa ) and various other seeds can also be processed into flour, as well as pulses ( beans , peas , chickpeas ). Potato starch is also known as "potato flour", but it is not created by grinding. Cassava flour is made by soaking the grated tubers, pressing the mass and then drying.

In a broader sense, there are also flours that are produced by grinding but are not used in the kitchen, e.g. B. fish meal (a feed ), bone meal (a fertilizer ) and quartz meal (found in abrasives , among other things ). Wood flour is a by-product of wood processing (“sawdust”).

etymology

The word flour was Old High German melo , Middle High German mël . It belongs to the same family of words as grind or the old grain measure Malter (actually "as much grain as is ground at once").

The Latin words molere "grind", mola "mill stone", molina "mill", molitor "miller" (cf. also the foreign word molar "molar") are indo-European . The words mill and miller come from the Latin: mill ( mhd. Müle , ahd. Muli , mulin ) goes back to the late Latin molina "mill"; Müller (mhd. Miller < Mülner < mülnære , OHG. Mulinari ) in late Latin molinarius "Müller".

Melber (Middle High German melbære ) is a Bavarian-Austrian name for a flour trader. The job title is no longer in use, but lives on as a family name. A milk factory is a flour shop. In Fritz Schumacher's autobiography “stages of life” , a milk and pasta shop is described at the end of the 19th century .

Manufacturing

Grinding diagram for a rye mill (example)

According to the current state of the art, the grain in a grain mill is ground most efficiently between grinding rollers in the roller frame. In modern grain mills, after each comminution, sieving and sifting takes place in the plansifter in order to separate the different particle sizes. This combination of roller mill and plansifter is called a “passage”, of which a modern flour mill has a large number. 14 passages and more are common sizes. When grinding wheat, semolina cleaning machines can also be used in such passages between the plansifter and the roller mill. By reducing the distance between the rollers of the individual passages, the grist is ground more finely. Here be Endospermpartikel , which are smaller than 150 microns, equal withdrawn as flour, larger particles are passed to the next passage.

In the course of production, the fat-containing seedling is removed from the flour by sieving for reasons of durability and the outer layer or shell of the grain. Grits are fed to the grit cleaning machine, grits are fed back to a passage.

Grain can be ground to different degrees of fine. In addition to the flour, different amounts of meal , semolina , haze and bran occur depending on how the product is handled ( joint production ). Flours and meal can also be ground through , i. that is, no flour is drawn out beforehand. Then wholemeal flours and meals are created. The nutritional content of the flour also depends on the degree of grinding.

The directly ground passage flours are processed into commercial flours in the mill. The passage flours are mixed with one another in mixing machines in the required ratio in order to obtain the desired product properties, if necessary with the addition of auxiliary substances such as malt flour or ascorbic acid. Some properties of the commercial flours produced in this way are regulated by law and in Germany must meet the requirements of DIN 10355.

composition

Soft wheat flour consists of approx. 59–72% carbohydrates (starch and mucilage, including 2.4–7% dietary fiber ), 14–15% water, 10–12% proteins (of which 80% gluten and 20% soluble proteins), 0.9-2.3% fat and 0.4-1.7% mineral salts.

Flour with a high degree of grinding is dark and richer in vitamins (especially B vitamins) and minerals , as a high proportion of the peel (also called bran ) is also ground. Flour with a low degree of grinding, on the other hand, is light and rich in starch , which is contained in the ground cereal core.

The typical particle size of flour is less than 180 µm. In connection with the degree of grinding, one also speaks of extract flour and assigns the brightness of the flour, for example wheat, spelled or rye, standardized according to DIN 10355, to a so-called type.

Types of flour

Muffle furnace for mineral determination at 900 ° C

Typing in Germany according to DIN

The term "the flour type" or simply "the type" comes from the technical language of millers and bakers and is a measure of the mineral content of the flour. The type or brightness is determined by determining the mineral content. Low flour types such as 405 - with a low mineral content - are very light, high types such as 1800 are very dark and rich in minerals. To determine the type, a small amount of the flour is burned in a muffle furnace at 900 ° C under laboratory conditions . The remaining (non-combustible) components essentially correspond to the amount of minerals in the flour. In the past they were also known as the "ash content of flour".

DIN standard 10355 has been in force in Germany since 1992 for typifying ground products made from common wheat, rye and spelled. The flour type indicates the average mineral content in mg per 100 g dry matter.

Flour types according to DIN 10355
designation Flour type Baking properties Minimum mineral content
(% in dry matter)
Maximum mineral content
(% in dry matter)
wheat
Wheat flour WM Type 405 preferred household flour, good baking properties - 0.50
Wheat flour WM Type 550 Powerful for fine-pored dough and can be used as a multi-purpose flour 0.51 0.63
Wheat flour WM Type 812 for light mixed breads 0.64 0.90
Wheat flour WM Type 1050 for mixed breads or baked goods in the household 0.91 1.20
Wheat flour WM Type 1600 for dark mixed breads 1.21 1.80
Durum wheat flour DM Type 1600 Durum wheat flour 1.55 1.85
Wheat baked meal WBS Type 1700 without a seedling - 2.10
Spelt
Spelled flour DM Type 630 In terms of baking, it can be used similar to wheat flour type 550 - 0.70
Spelled flour DM Type 812   0.71 0.90
Spelled flour DM Type 1050   0.91 1.20
rye
Rye flour RM Type 815 only rarely used, mostly in southern Germany,
for light rye bread
- 0.90
Rye flour RM Type 997 for mixed breads, distributed differently from region to region 0.91 1.10
Rye flour RM Type 1150 for mixed breads, distributed differently from region to region 1.11 1.30
Rye flour RM Type 1370 typical "baker's flour" for
rye and mixed rye breads
1.31 1.60
Rye flour RM Type 1740 typical "baker's flour" for
rye and mixed rye breads
1.61 1.80
Baked rye meal RBS Type 1800 without a seedling - 2.20

Whole grain products (flour, meal) as well as wheat semolina and wheat fumes are classified by DIN 10355, but their mineral content is not specified and they are therefore not given any type numbers. Whole grain products always contain the seedling. Baked meal differs from whole grain meal in that it no longer contains any seedling.

Classification of grit and haze
(according to DIN 10355)
in% sieve residue on the sieve bottom
mm mesh size 0.8 0.5 0.315 0.224 0.16
Wheat semolina (WG) 0 - ≥ 25 ≥ 90 -
Wheat fume (WD) - 0 <25 - ≥ 90

As part of the EU research project HealthGrain, a European wholegrain definition was developed which, on the basis of current scientific knowledge, describes the term "wholegrain" as follows: "Wholegrain should consist of whole, ground, crushed or flaked grains after the inedible parts, how husks and pods were removed. The main components of the anatomical structure - the starchy endosperm, the seedling and the shell - are present in the same proportion as in the whole grain. "

Since grain as a natural product is subject to great fluctuations in quality and composition depending on the climate and weather , the flours obtained from them are often mixed so that, in addition to their brightness (type), they also meet certain mechanical and enzymatic specifications. These are decisive for the baking ability of the flour.

Typing in Austria

In Austria, the DIN typification is not valid, the regulation is carried out by the Austrian Food Book . The type numbers given mean the mean 1000 times the mineral content in% of the dry matter, the type of grain. The preceding letter agreed with the type of grain (W = wheat, R = rye), spelled flours are only designated according to the mineral content (flour type). Besides flour after increasing grain size are divided as follows: smooth , rough and double grip ; Dunst or semolina, unlike in Germany, are subject to the same typification. Other names such as B. extra fine or universal are trade names and not written down in the food book. The maximum humidity is 15.5% for all types of flour and 14.5% for whole flours in small packages.

Flour names according to the Austrian food book
Flour type Baking properties Mineral content
(% in dry matter)
comparable to DIN 10355
wheat flour
Type W480 Wheat extract flour (for fine baked goods, e.g. cakes) 0.33-0.58 Type 405
Type W700 Wheat cooking and baking flour 0.66-0.79 Type 550
Type W1600 Wheat bread flour 1.50-1.75 Type 1050
Type W1800 Whole wheat flour with sprout and shell
Rye flour
Type R500 Rye flour 0.43-0.57 Type 815
Type R960 Rye bread flour 0.88-1.12 Type 997 or 1150
Type R2500 Black rye flour 2.00-3.00
Whole grain rye flour 1.5-2.3
Spelled flour
Type 700 Spelled flour ~ 0.7
Type 1800 Wholemeal spelled flour ~ 1.80

Typing in Switzerland

In Switzerland, the DIN typification is not used, at least officially. A distinction is made between different degrees of grinding, which are defined on the basis of the mineral content. Basic flours for bakeries in sacks weighing 25 kg or more are often marked with the flour type according to DIN.

Information on flours in Switzerland:

Type of flour Degree of grinding Definition according to Art. 63 VLpH Mineral content
( Art. 67 VLpH)
Type
White flour Wheat flour approx. 65% of the grain «Flour obtained mainly from the inner part of the grain» ≤ 0.63% 400… 550
Semi-white flour Wheat flour approx. 75% of the grain "Almost peel-free flour" 0.64-0.90% 700 ... 750
Ruchmehl Wheat flour approx. 85% of the grain "Flour that still contains part of the outer shell layers" 0.91-1.69% 1050… 1100
Whole wheat flour Wheat flour min. 98% of the grain «Flour obtained from the whole grain,
with or without the outer shell parts;
however, the total yield must be at least 98 percent by mass of
the total grain. "
≥ 1.70%

Typing in France

The AFNOR standard NF V 03-720, which is based on the ISO standard 2171, has been in force in France since 1963 for the typification of ground products made from common wheat and rye . The flour type indicates the mean mineral content in mg per 10 g dry matter.

Flour types according to AFNOR NF V 03-720
Flour type Baking properties Minimum mineral content
(in%)
Maximum mineral content
(in%)
wheat flour
Type 45 for the finest doughs for making confectionery products - 0.49
Type 55 can be used for fine doughs and as a multi-purpose flour 0.50 0.59
Type 65 Powerful for white breads and light breads of all kinds 0.62 0.65
Type 80 for light mixed breads 0.75 0.90
Type 110 for rustic bread 1.00 1.20
Type 150 for dark mixed breads > 1.40 -
Rye flour
Type 70 for light rye breads or for adding to mixed wheat bread 0.60 1.00
Type 85 for mixed breads 0.75 1.25
Type 130 for rye and mixed rye breads 1.20 1.50
Type 150 for rye and mixed rye breads > 1.50 -

Prescribed limit values ​​in Italy

Name of the product Humidity max Minerals min. Minerals max. Protein min.
Soft wheat flour tipo 00 14.50% - 0.55% 9.00%
Soft wheat flour tipo 0 14.50% - 0.65% 11.00%
Soft wheat flour type 1 14.50% - 0.80% 12.00%
Soft wheat flour type 2 14.50% - 0.95% 12.00%
Wholemeal soft wheat flour 14.50% 1.30% 1.70% 12.00%

Comparable types of flour

Italian name Mineral content max. Protein content min. Comparable to
tipo 00 0.55% 9% Type 405
tipo 0 0.65% 11% Type 550
tipo 1 0.80% 12% Type 812
tipo 2 0.95% 12% Type 1050
Whole wheat flour 1.70% 12% Type 1600

Other types of flour

The following terms are not standardized. Nevertheless, some mills offer flours with these names as special flours.

  • Tacky flour and particularly double grip flour has a tangible nature, the haze comparable. Spaetzle flours are typical examples. Grippy flours have a better baking behavior than smooth ( ground ) flours because they absorb the water more slowly and result in drier and firmer doughs.
  • Instant flour - (Instant flour is a flour made from hard or soft wheat that has a high flowability and easy wettability. Therefore, it can absorb up to 2% more water and can be processed into a dough more quickly. It is mainly used in households.)
  • White flour (in Switzerland: white flour ) is a light wheat flour (also: extract flour ).
  • With black flour a rye flour or very dark wheat flour was meant.

Additives (flour treatment agents)

declaration

In the case of prepackages that are handed over to the end consumer, the flour treatment must be declared in the list of ingredients. (Exception: enzymes )

Example wheat flour, list of ingredients:

  • wheat
  • Flour treatment agent: L-ascorbic acid

Chemical preservation or the bleaching of flours or coloring is not permitted under German food law.

Ascorbic acid

Often ascorbic acid (vitamin C or E 300 ) is added to wheat flours ( 1–2 g / 100 kg flour). There are technological reasons for this: ascorbic acid strengthens the adhesive structure and thus ensures better baking results. Oxidation of ascorbic acid with atmospheric oxygen forms dehydro-ascorbic acid in the dough. The dehydro-ascorbic acid acts as an oxidizing agent in the dough and promotes the formation of disulphide bridges , which increases the cross-linking of the gluten proteins. An increase in cross-linking results in a firmer dough. B. can be measured by means of an extensogram . During the baking process, the ascorbic acid is destroyed because it is not heat-resistant.

Amylases

Biotechnologically produced amylases (from bacteria or mold cultures ) are used as flour treatment agents when the flour is poor in starch-degrading enzymes and therefore its ability to form gas during baking is too low. The amylases produce fermentable single and double sugars , which are converted into ethanol and carbon dioxide by baker's yeast during cooking , thus allowing the dough to rise. In addition, the baked goods are better browned after the treatment.

Proteases

Biotechnologically produced proteases (from bacteria or mold cultures ) are used as flour treatment agents when the adhesive structure of a wheat flour is too tight and the gluten structure prevents the dough from rising sufficiently. The application originally came from the USA , where traditionally very strong adhesives make it difficult to produce hard biscuit or cracker flours. Proteases break down the amino acid chains of the adhesive and thus ensure that the adhesive becomes softer and more elastic. In addition, proteases split off terminal -NH 2 groups, which improves the aroma development in baked goods.

Amino acids that are effective in baking

  • Flours treated with cysteine (E920) have a functionally similar effect to those treated with proteinases. Doughs made from this flour soften in comparison to the untreated reference dough.
  • Flours treated with cystine tend to have the same effect as those treated with ascorbic acid. The doughs made from this flour are firmer than reference doughs made with untreated flour.

Economical meaning

In the grain marketing year 2015/2016, 6.14 million tons of common wheat flour and 0.7 million tons of rye flour were produced in Germany. Domestic flour consumption was completely covered by the grinding of domestic grain for rye and common wheat. The average flour yield for common wheat was 80.5% and for rye 89.6%.

In the 2014/2015 marketing year, the average per capita consumption of flour was 72.6 kg (hard and soft wheat flour 64.6 kg and rye flour 8.0 kg).

use

Flour is used as the base of dough for making baked goods or pasta . Approx. 3000–4000 rolls can be made from 100 kg of flour.

The amount of flour in a dough is used by bakers as a mathematical basis for determining the other ingredients. The amount of flour is used as a reference value of 100%. One speaks of "yields" when the dough weight is related to the flour weight. The dough yield varies depending on the addition of water. It depends on the flour's ability to bind water. With the same flour, a soft dough therefore has a higher dough yield than a firm dough; the dough yield therefore varies with different baked goods.

Flour is also an important raw material for thickening many sauces , seldom soups too, and is used here in the form of roux (Austrian: stoving) . This is also the starting material for the gruel , a traditional carnival dish , especially in Switzerland.

storage

Wheat flour packed in 40 kg bags in a mill

Flour is properly stored at below 20 ° C and a relative humidity of below 65%. Under these conditions, light flours (up to approx. Type 812) can be stored for around 1 year to 1½ years, darker flours (up to Type 1050 or Type 1370) for around six to eight months and whole grain products for around six to eight weeks without any loss of quality. If stored for a longer period of time, the breakdown of fatty acids (from the seedling and the shells) begins and the flour begins to go rancid .

When flour is exposed to direct sunlight, the flour dyes decompose very quickly and the flour bleaches.

Flammability

The distribution of flour dust in the air creates a mixture that can explode if ignited. The enlargement of the surface of flour particles finely distributed in the air enables a very high reaction speed and thus an explosive reaction.

The largest flour dust explosion in German-speaking countries to date took place on February 6, 1979 in the Rolandmühle in Bremen . Several explosions were triggered one after the other in a chain reaction . 14 people died, 17 were injured and the property damage amounted to 100 million D-Marks , making it the largest single loss in Germany to date.

Osh

Flour dust at the workplace can pose an inhalation hazard for employees . There is no occupational exposure limit for flour dust . According to TRGS 907, flour dust is respiratory sensitizing. In the work safety information "Avoidance of baker's asthma" (ASI 8.80), work procedures are shown that must be used in bakeries in order to minimize the risk of baker asthma and rhinitis occurring .

In flour stores, rooms for dough production and dough processing as well as other areas with relevant exposure to flour dust, the recommendations “Flour dust in bakeries” help employees to work with little dust. The recommendations apply to bakeries, confectioners and manufacturers of other baked goods that are exposed to flour dust, but not to flour mills. They are based on measurements of the inhalable fraction ( E-dust ) in the air at workplaces.

If appropriate technical, organizational and personal protective measures are complied with, you can dispense with metrological monitoring.

See also

Web links

Commons : flour  - collection of images, videos and audio files
Wiktionary: flour  - explanations of meanings, word origins, synonyms, translations

Individual evidence

  1. Principles for bread and biscuits
  2. Pictures of the traditional production of cassava flour www.online.uni-marburg.de
  3. See Duden online: flour
  4. ^ Duden online: Flour , grind , Malter
  5. Duden: The dictionary of origin. 3. Edition. 2001, keywords grind, mill, miller .
  6. ^ Duden online: Melber
  7. a b c DIN 10355: 1991-12, ground products made from grain; Requirements, types, testing
  8. a b c Waldemar Ternes , Alfred Täufel, Lieselotte Tunger, Martin Zobel (ed.): Food Lexicon . 4th, comprehensively revised edition. Behr, Hamburg 2005, ISBN 3-89947-165-2 .
  9. a b Burghard Kirsch: Milling technology, materials science . Composition, study, evaluation and use of grain and grain products. 8th edition. Bayerischer Müllerbund, Munich 2016, ISBN 978-3-9812436-0-4 . , Page 175
  10. Definition of whole grain  ( page no longer available , search in web archivesInfo: The link was automatically marked as defective. Please check the link according to the instructions and then remove this notice. HealthGrain Forum (English)@1@ 2Template: Dead Link / www.healthgrain.org  
  11. Austrian Food Book - Chapter B20, Milled and peeled products. Federal Ministry of Health, accessed on April 5, 2020 .
  12. Mills usually specify the type of flour, the exact type varies from milling to milling or they offer several types per flour (e.g. white flour types 400 and 550 at a Lucerne milling factory: [1] )
  13. https://moulins-antoine.fr/nos-farines/les-differents-types-de-farine/
  14. Rose flour: Our rose flour. Retrieved August 26, 2020 .
  15. Werner Grosch: Mechanism of the ascorbic acid effect . In: cereals flour and bread . tape 52 , no. 5 . Detmold 1998, p. 267-269 .
  16. a b Statistical Yearbook on Food, Agriculture and Forests 2016 , at bmel.de, accessed on September 5, 2017
  17. Imke Molkewehrum: The worst detonation since the war shakes Bremen in the Weser Kurier on March 5, 2015, accessed on July 10, 2016.
  18. a b c German Statutory Accident Insurance e. V. (DGUV): DGUV Information 213-705 - Recommendations for hazard assessment by the accident insurance institutions (EGU) according to the Hazardous Substances Ordinance - Flour dust in bakeries. Retrieved October 30, 2019 .
  19. Professional Association for Food and Hospitality (BGN): ASI for download. Retrieved October 30, 2019 .