DE4494352C2 - Method of homogenising grain by quick impact-mixing treatment - Google Patents

Abstract

Semi-finished prods. for foodstuffs, fodders, etc. are prepd. from grain by homogenising it by quick impact-mixing treatment under controlled temp. and moisture conditions.

Description

The invention relates to a method for producing a Semi-finished products made from cereals for food, feed and the like, by homogenizing the grain under controlled temperature and humidity conditions. The semi-finished product thus obtained can, for. B. a whole wheat dough be used for the production of whole grain bakery products becomes.

DE 3 733 689 A1 describes a method for producing a Bread dough, with the crushed cereal grains with the other dough components with the addition of water and gases processed into a foam-like dough mass. DE-PS 1 70 044 describes a process for making bread from pre-swollen grains and legumes under pressure. EP 0 208 252 A2 describes a process for the production of Bread, with only the very thin, the outer grain coating covering layer is rubbed off and the cereal grains then not ground, but only by maceration for several hours.

An essential feature of the method according to the invention is that cereals without a previous crushing or Milling phase is processed. For example in manufacturing Whole grain dough becomes whole grain Grains, instead of the traditional use of flour, with other dough ingredients combined, after which a dough through Stir the dough mixture into a wet grinding conditions homogeneous mass is prepared, taking the whole grains be crushed at the same time. When processing the Grain is thus left out of the conventional milling phase,  because the grain as whole grains, i.e. H. in unground Form, at bakeries or other processing plants can be delivered.

The milling phase traditionally makes up a substantial part of the Processing of grain before the baking phase. In a typical, modern mill, grain is cleaned first, dried (if necessary) and then conditioned, d. H. of the Moisture content of grain that is moist from storage (below 14%) to facilitate divorce from bran to about 16% elevated. In the case of bread cereals, the next phase is that actual grinding which step in step Roller mills takes place, the grinding, screening, sorting and Carry out grinding. Medium coarse in the shot phase Grains are covered with plansifters and grain cleaners different degrees of granularity. A part of medium-sized grains become subsequent, finer rollers headed a part to cleaners. Cleaners separate them medium coarse core and surface grains through sieving and Gravity divorce (core fractions are heavier). Medium-sized surface grains are ground again. Flour obtained with plan sifters is turned into Container directed. Flour of uniform quality packed up. Ripening agents, ascorbic acid, amylase and Protease enzymes can be added to the flour during grinding will. Wheat flour can also be bleached and with vitamins and Minerals are supplemented.

For example, wheat becomes the following when grinding Products received: Wheat bran, wholegrain meal, wheat germ, Groats and wheat flour (whole wheat flour, white bread flour, All-purpose wheat flour, medium-coarse wheat flour, coarse Wheat flour and special or core wheat flour).

When grinding rye there is a significantly smaller number Grind fractions recovered. They contain rye flour (Whole rye flour, sifted rye flour, fine rye flour)  and whole rye meal. Rye flour is not bleached, enriched or supplemented. Grinding of barley and oats and manufacture of barley and oat flakes include theirs own special process phases (e.g. polishing and peeling) on.

In this way, crushed grain is sent to bakeries delivered where a dough is typical by combining the flour with water, yeast, salt and other possible additives is prepared. The dough can vary Processes are prepared, the most common of which One-step procedure and the multi-step procedure are. in the All raw materials are added to one stage process at the same time mixed into a dough that typically kneads for 8 to 20 minutes becomes. This process is the most widely used for making Wheat bread and mixed bread used. In the multi-stage process part of the flour to be used for a dough in one Preliminary stage or several preliminary stages (sour, sourdough etc.) treated. Using this method, for example, will be almost all rye bread products made. If the baking raw material consists of flour, of which one of the cereal components (usually peel or germ) is one separate grinding phase necessary. For production of Whole grain products, on the other hand, can also contain whole grains in addition to flour be used.

However, it is currently a general practice that Grinding phase and the baking phase also when producing Separate whole grain products. Whole grain conventionally made in a normal mill by combining fractions from different ones Grain levels so that the final whole grain all Contains cereal grain components.

Because whole grains contain all grain components (such as those containing fat Germ that easily becomes rancid) is too note that it spoils quickly or at least gets in  its quality in a relatively short time worsened. The shelf life of whole grains (several years) is of a completely different order of magnitude than that of flour. When cereal grains for baking Whole grain products are used as raw material, that will Avoided expiration problem of flour and the time span between grains and a final baked product minimizes what the taste and freshness of the product will certainly affect.

The method according to the invention is also very useful if no grinder is available, although grains are present and if the final baked product is as quick as possible should be obtained from grains.

The invention relates to a method for producing a Semi-finished products made from cereals for food, feed or the like, by homogenizing the grain under controlled temperature and humidity conditions.

The semi-finished product is especially a whole grain dough, such as a whole wheat or whole rye dough. It can also be a grain-based carrier material for mixtures of Be baking additives. The semi-finished product can be used for this Product made from wheat, rye, barley or oats be for use in starch and feed industries is provided.

The homogenization of cereals refers to this Refining cereal grains at the same time Mixing to a homogeneous product. To be homogenized Cereals can be made from whole grains, peeled grains, pre-crushed grains (grain fragments) or peeled, pre-crushed grains. The fall number of the grain is not a limiting factor, but even grain a low case count can be used in the process. The moisture content of the grain is also not  restricting, although it is common, grain that is moist from storage (Moisture content about 12 to 14%).

Cereal grains to be processed are used before cleaned by conventional methods, namely for Eliminate grain when harvesting and threshing mixed impurities (straw, stones, etc.).

Grain can be dry (if it is damp) or in the presence of liquid, usually water. If grain is moist when stored without liquid or in Presence of as little fluid as possible a high homogenizing capacity is processed, the Grain temperature under the influence of mechanical Energy to which these are exposed, the grains not only refined, but also heat treated, what the Falling number of grains increased, d. H. the baking properties of the Grain improved. In this way, cereals with a low case number can be used as raw material. From the Heat treatment results in a homogenized, heat-treated, almost dry cereal powder, the used immediately or after storage as a dough component can be.

If, for example, a whole grain dough is prepared, Cereals homogenized in the presence of dough liquid.

Homogenization of grain can be done in any device capable of breaking the grains and under both dry and wet conditions and within a relatively wide temperature range is working. Preferably a device from the blow mixer-type used that even under humid conditions is working.

Temperature and humidity are regulated by the Performance of the homogenizer and / or the  Checked the amount of liquid in the homogenizer. As above mentioned, the temperature of the grains increases when using a high mixing / refining performance and the smallest possible Amount of liquid due to the mechanical energy that the Grains are exposed so that the grains are heat treated will. A relatively large amount of liquid will used when the dough prepared from the grains should be baked immediately. In contrast, will be a very small amount of liquid and a low temperature used when preparing a so-called dry dough.

Homogenization of cereals, for example during preparation Whole grain dough is preferably used as wet grinding in a mixer type.

This is used to regulate the homogenization of cereals Homogenizer with a sieve and / or sorting device connected. One obtained from the screening and / or sorting phase coarse fraction can thus be refined into the Homogenizer are returned.

The following is the invention in terms of preparation of a whole grain dough described in more detail.

The invention particularly relates to a method for Production of a whole grain dough by combining whole Grains with other dough ingredients and by stirring the obtained mixture to a homogeneous dough by wet grinding. The whole grain dough obtained in this way usually becomes after conventional baking process immediately to a final one Whole grain baked product.

Grain raw material can be of any type, however the invention relates in particular to the preparation of a Whole rye dough used for the production of Wholegrain rye products, e.g. B. rye crispbread and sour or unleavened, fresh rye bread  should. Wheat can also be used. It is further possible to combine wheat and rye. Cereals with a lower number of cases can also be used because the Number of cases during dough preparation by regulating the Mixing performance and the amount of dough liquid so changed can be that the dough obtained is suitable Will have baking properties. In the process, ordinary grain that is moist from storage is used. It is also possible, undried grains (moisture content below 30%) use, especially in cases where they are very soon can be used after harvest. Grains are considered whole grains or possibly according to regulations (as Grain fragments) processed.

To prepare a dough for wholegrain rye bread become rye grains with water, yeast, salt and others possible additives combined, and the mixture is stirred by wet grinding to a homogeneous dough. For Production of fresh, sour rye bread is also done Rye acid mixed in. The mixture of Dough ingredients undergo intensive mixing and grinding subjected to a wet grinder. Wet grinding can be done in anyone any mixer / grinder can be executed, the one has sufficient power to break the grains and that is able to function under wet grinding conditions. On Atrex mixer (supplier Flowcon Ltd., Valkeakoski, Finland) can be used for example. With wet grinding all dough components in intimate contact with each other brought.

A finished dough thus obtained is made according to conventional Process for final bakery products, such as fresh bread, Baked crispbread, cookies, etc. The dough obtained is preferably for the production of fresh rye bread, such as hollow rye loaves (a round, flat rye bread with a Hole in the middle), and rye crispbread used.  

For the production of so-called ice bread, except the conventional dough ingredients, gas (air or carbon dioxide) mixed with the dough. The process takes place at a low Temperature from about +4 to + 8 ° C instead. A sufficient one low temperature is e.g. B. with a heat exchanger causes. At such a low temperature one remains optimal amount of gas in the dough so that the bread later under the Exposure to the gas rises when the temperature rises becomes.

The amount of water in wet grinding can vary. For Preparation of rye dough is typically about 1 kg of grains per 700 to 900 g of water used. For the preparation of sourdough 1 kg of grains is used per 1.5 kg of water, based on the final batter. For the preparation of so-called dry dough only about 0.3 kg of water is used per 1 kg of grains, and the process takes place at a very low temperature. Such a dry dough holds up relatively well if he is kept cool; on the one hand it does not spoil and on the other hand, its microorganisms remain viable for you later acidification of the dough. Because dry dough storage and Delivery withstands well, it is possible to get a larger amount Making dough in a grocery store and making it then to produce final baked products to smaller ones Deliver to bakeries.

In the wet grinding phase it is also possible to reduce the number of cases from Lower quality cereals. The Operating temperature of the device rises when high Grinding / mixing performance used or the amount of dough liquid is reduced, the grains being heat treated, while inactivating the α-amylase enzyme of the grains. Each the higher the α-amylase activity, the lower the Number of cases and the worse the baking properties of the Grain. Such bad baking properties exist for Example with rye from reduced dough yield, extreme strong rising, increased loaf volume at the expense of  Bread structure, very dark crust color, worse Bread structure and dark crumb, lack of crumb elasticity, chewing gum-like structure of the bread crumb and sweet taste of bread. The method according to the invention allows one Increase the number of cases z. B. from 62 to 150 what the Improved usability of lower quality cereals.

Cereal starch can be obtained by performing wet grinding in Presence of hot water or introduction of hot steam be pre-gelatinized into the material to be shredded. Preserved, pre-gelatinized dough can improve the freshness properties of the end product (bread) (the so-called skallning process; L. Ask, Livsmedelteknik 1-2 (1989), pp. 12-15) can be used as a dough component.

Wet grinding brings all the dough components together Contact each other what the baking properties of the dough improved. This way the use of Additives, e.g. B. emulsifiers and enzymes, minimized will.

It is also possible to sort and / or sort the mixing (wet grinding) of the dough by coupling, for example, a wet sieve after Mixing unit. The coarse fraction can thus Further refinement can be returned to the mixer. In In the same way, screening / sorting according to regulations be carried out. This way it is possible to get closer to the Particle size distribution of normal, coarse rye flour too come, and a larger amount of fine flour will get what, influenced the properties of the end product favorably. The refined fraction contains large amounts of broken Starch that can be used as a nutrient for yeast or bacteria is. Another split of the broken starch, e.g. B. enzymatically, produces sugar that gives the bread color and taste to lend.  

Screening / sorting devices also generally allow regulation the ratio between coarse and fine flour fractions in the final baked product.

The invention will be further elucidated by means of the following Exemplary embodiments illustrated.

In the examples, two commercially available devices for Dough preparation used: Atrex grinder and Atrex mixer (Equipment supplier Flowcon Ltd., Valkeakoski, Finland). This Devices can be used for grinding and mixing materials very much varying types can be used. Based in the devices Grinding and mixing on the use of impact energy and Friction. They can mainly be used as devices from Mixer type can be classified. In such devices the grinding takes place in a substantially horizontal Chamber takes place in which the grinding / mixing agents (plates) in one variable angles are / can be arranged to each other. The mutual position of the grinding / mixing agents can be varied, which allows control of the grinding capacity (the grains may pass through in an almost unground state, or after having a sufficient, desired Have been suspended).

example 1 Production of dough from whole grains

Untreated rye grains (number of cases of rye 130) were with a screw feeder in the above Atrex mixer introduced (mass flow rate 5 kg / min). A premixed suspension of sourdough (= acidified Rye dough), yeast, salt and water was made by a Dosing device with a mass flow rate of 7.1 kg / min introduced. The amounts were as follows:

Unmilled rye: 24.0 kg
Rye sourdough: 24.0 kg
Water: 8.0 kg
Yeast: 1.5 kg
Salt: 0.58 kg

The sourdough contained 8.6 kg of rye flour (fine, Melia) and 15.4 kg of water. The pH of the leaven (18 h) was 3.5 and whose acid number is 20.5.

Processing conditions in the mixer were as follows:

Upper rotor (RPM ^-1 ): 1900
Lower rotor (RPM ^-1 ): 1500
Grain mass flow (kg / min): 5.0
Liquid mass flow (kg / min): 7, 1
Rye temperature (° C): 13
Liquid temperature (° C): 22
Dough temperature (° C): 30

The grains were broken down into flour when they blended the mixer happened. The following table shows the Particle size distribution obtained when dry Grains processed in the mixer without the addition of dough liquid were.  

Table 1

Particle size distribution of dry milled rye in the mixer

If the grains were ground in the mixer, they would too mixed with the dough liquid, and the device produced a dough that was used for the following test baking. in the Comparison with the production of a normal rye dough the treatment time of the dough (usually about 7 to 10 min) significantly shorter in the mixer. The temperature rise of the Dough is due to the work involved in mixing is performed.

The resulting rye batter became hollow rye loaves baked. The following were used in the baking process Baking conditions used that the average Processing values for hollow rye loaves correspond to:

Dough resting time (min): 60
Dough temperature (° C): 26.5
Shapes: +
Gross weight (g): 370.0
Dough rest (min / ° C / RH): 70/36/75
Baking (min / ° C): 35/230
Steam: normal
Weight after baking (g): 265.0
Baking loss (%): 28.5

The test loaves were conventional, made from rye flour loaves produced and had a fresh, good Taste. The baking properties of the dough corresponded to those a dough made from normal, coarse rye flour.

Reference example Production of dough from pre-ground Cereal grains

In this example, the procedure was the same as above, except that rye grains are first described in the above Atrex grinder were pre-ground. Grinding conditions in the grinder were as follows:

Upper rotor (RPM ^-1 ): 2300
Lower rotor (RPM ^-1 ): 2300
Feeder (%): 20.6
Mass flow (kg / min): 758
Grain temperature (° C): 12.0
Flour temperature (° C): 16.4

After grinding, the flour was used to cut unground Grains and the coarsest fraction in a sieve of about 2 mm sieved (sieving takes place under normal grinding conditions automatically takes place during grinding). The following table shows the particle size distribution of that obtained from the grinder Flour (that of the particle size distribution of the from the mixer flour obtained), the particle size distribution normal, coarse rye flour and other properties. It it should be noted that the number of cases remained unchanged.  

Table 2

Particle size distribution of rye ground in an Atrex mill and of normal, coarse rye flour, and other properties

Pre-ground rye was obtained from a screw feeder (Mass flow rate 5 kg / min) in the above described mixer introduced, and a premixed Suspension of sourdough, yeast, salt and water was included a dosing device (mass flow rate 7.1 kg / min) introduced. The amounts of the various ingredients were the same as in Example 1. Process conditions for mixing were as follows:

Top rotor (RPM ^-1 ): 1300
Bottom rotor (RPM ^-1 ): 1300
Flour mass flow (kg / min): 5.0
Liquid mass flow (kg / min): 7.1
Rye temperature (° C): 12.5
Liquid temperature (° C): 22
Dough temperature (° C): 30

All raw materials became one in the mixer Dough mixed in the same way as in the example 1 was baked into rye loaves. Baking conditions were as follows:

Dough resting time (min): 60
Dough temperature (° C): 26.0
Shapes: +
Gross weight (g): 370.0
Dough rest (min / ° C / RH): 70/36/75
Baking (min / ° C): 35/230
Steam: normal
Weight after baking (g): 276.0
Baking loss (%): 25.6

The loaves obtained were those in Example 1 received very similar.

Other uses

The general discussion above and the experimental examples are intended to illustrate the present invention. Other Variations in the spirit and scope of this invention are possible and will surrender to the expert. For example, the dough produced by the method of Example 1 also for Production of other types of fresh whole rye bread are used, e.g. B. rye shaped breads and round Oven grilled bread.

The same process can also be used to make a dough for Rye crispbread and rye biscuits can be used. As  Raw grain of rye can be used by Wheat grains or a mixture of wheat and rye grains be replaced.

Claims (18)

1. A method for producing a semi-finished product from cereals for food, feed or the like, characterized in that the cereals are homogenized by rapid impact mixing treatment under controlled temperature and humidity conditions. 2. The method according to claim 1, characterized characterized in that the grain in the form of whole Grains, peeled grains, pre-crushed grains or peeled, pre-crushed grains is homogenized. 3. The method according to claim 1 or 2, characterized characterized in that the grain in the presence of Liquid is homogenized. 4. The method according to any one of the preceding claims, characterized in that the temperature and Moisture by regulating the performance of the Homogenizer and / or the amount of liquid in the Homogenizer can be checked. 5. The method according to any one of the preceding claims, characterized in that a whole wheat dough is prepared. 6. The method according to claim 5, characterized characterized in that the whole wheat dough is produced that the grain in the form of whole grains is combined with other dough ingredients and the Blending into one by rapid impact mixing treatment homogeneous dough is stirred.   7. The method according to claim 6, characterized characterized in that a whole rye dough by is made that whole rye grains with water, yeast, Salt and other possible additives can be combined and the mixture through rapid impact mixing treatment a homogeneous dough is stirred. 8. The method according to claim 6, characterized characterized that an unleavened or acidic Wholegrain rye dough is made by whole Rye grains with rye sourdough, water, yeast, salt and other possible additives can be combined and the Blending into one by rapid impact mixing treatment homogeneous dough is stirred. 9. The method according to claim 6, characterized characterized in that gas in the Mixing phase in the batter additionally is mixed in. 10. The method according to any one of the preceding claims, characterized in that the milling of cereals by combining the stroke treatment phase with a Screening and / or sorting device is regulated. 11. The method according to claim 10, characterized characterized in that a coarse fraction from the Screening and / or sorting device for further refining in the Impact mixing phase is returned. 12. The method according to any one of the preceding claims, characterized in that a cereal product is produced in which the falling number of grains by Increasing the homogenizing performance and / or by reducing the amount of liquid in the homogenizer has been increased.   13. The method according to any one of the preceding claims, characterized in that a dry batter through Reduction of the amount of liquid in the homogenizer and made by operating at a low temperature becomes. 14. Whole wheat dough made according to a method according to one of the Claims 5 to 13 is prepared. 15. Grain-based carrier, which according to a method according one of claims 1 to 4 is prepared for mixtures of baking additives. 16. Using a wholemeal dough made after a Method according to one of claims 5 to 13 is prepared, for the production of whole grain bakery products. 17. Use of a whole rye dough, which according to Claim 7 is prepared for the manufacture of Rye crispbread. 18. Use of a whole rye dough, which according to Claim 8 is prepared for the production of acid or unleavened, fresh rye red.