CN103100458A - Method for improving flour quality by regulating damage of wheat starch grains - Google Patents

Abstract

The invention discloses a method for improving flour quality by regulating and controlling the damage degree of wheat starch, relates to grain intensive processing and utilization technology, and belongs to the field of food processing. In the present invention, the damaged starch content in the wheat flour can be increased by superfine grinding the wheat flour obtained by conventional grinding, and the damaged starch content of the unground flour is 6.54%. After that, the content of damaged starch increased to 7.30%, 8.86%, 9.66%, and 12.06%, respectively. When the content of damaged starch increases, the processing quality of wheat flour has been improved to varying degrees, thereby achieving the purpose of the invention to improve the quality of wheat flour by regulating the content of damaged starch. After the invention is implemented in wheat processing enterprises, it can produce wheat special flour with higher content of damaged starch, which has important practical significance and broad application prospects for the development of high-tech industries.

Description

A method for improving flour quality by regulating wheat starch granule damage

technical field

The invention relates to grain intensive processing utilization technology, belongs to the field of food processing, and specifically relates to a method for improving the quality of flour by regulating the damage degree of wheat starch. the

Background technique

Damaged starch means that when wheat is milled, due to mechanical rolling, a small amount of starch outer cell membrane is damaged, resulting in damage to starch granules. Damaged starch content of wheat will affect many properties of flour, such as water absorption of dough, rheological properties and quality of flour products. Wheat starch granules are damaged after grinding, and the water absorption rate of flour increases during the dough preparation process; after starch damage, the crystalline structure of the granules gradually transforms into partial crystallization and finally becomes amorphous, making it easy to be absorbed by α-amylase Hydrolysis is beneficial to the fermentation process. the

Different flour products require wheat flour to have different damaged starch contents. Starch granules and their post-damage characteristics have important theoretical guiding significance for wheat breeding, processing and quality of flour products. The wheat processing process is a physical process based on mechanical force and thermal factors. During the processing process, starch granules will be damaged due to the action of mechanical force and heat, which will lead to changes in flour quality characteristics. the

Therefore, by studying the relationship between the intensity of mechanical force and the degree of mechanical damage of starch granules, the degree of starch damage can be controlled by controlling the mechanical crushing intensity, and finally the purpose of improving the quality of flour can be achieved. The flour quality control method that needs is a problem that needs to be solved urgently. the

Contents of the invention

In order to overcome the deficiencies in the above-mentioned prior art, the present invention achieves a flour quality control method suitable for the needs of different flour products by regulating and controlling the degree of damaged starch. Systematic research has been carried out on the determination of flour quality indicators, the determination of damaged starch content, the determination of flour quality, and the determination of fermentation characteristics. the

The purpose of the present invention is achieved like this:

A method for improving flour quality by regulating the degree of wheat starch damage is characterized in that the wheat is pulverized by a superfine pulverizer after conventional grinding. the

The pulverizing power used in ultrafine pulverization is 45-130Hz. the

The damaged starch content of the flour obtained by superfine grinding ranges from 7.30% to 12.06%. the

The damaged starch content of flour obtained by superfine grinding is 12.06%. the

Positive and beneficial effects: the present invention can increase the content of damaged starch in the wheat flour by superfine grinding the wheat flour obtained by conventional grinding, so as to improve the flour quality and meet the needs of flour product processing. After the invention is implemented in wheat processing enterprises, it can produce wheat special flour with higher content of damaged starch, which has important practical significance and broad application prospects for the development of high-tech industries. the

Detailed ways

In order to realize the purpose of the invention, the grain characteristics of the raw material wheat were first measured, and the single grain grain analyzer (SKCS) was used to measure. The measurement results showed that the grain hardness of the wheat grain was 67.73, which was hard wheat, and the single grain grain weight of the grain was 41.63mg. The diameter is 3.06mm; then use BUHLER experimental grinding, refer to the AACC method 26-20, determine the amount of water to be moistened according to the hardness of the grain, the water content of hard wheat is 16%, the time of moistening is 24h, and the average feeding speed of the mill is 100g/min; then put the obtained flour into the superfine pulverizer respectively, and pulverize with the power of 45Hz, 70Hz, 100Hz, 130Hz respectively to obtain superfine pulverized flour samples; the superfine pulverized flour is measured by AACC 76-31 method Damaged starch content, the measurement results show that the damaged starch content of unground flour is 6.54%, after the crushing process with an intensity of 45Hz, the damaged starch content increases to 7.30%, when the crushing intensity is 130Hz, the damaged starch content is 12.06%, Compared with the unground flour, the content of damaged starch has increased by about one time. It can be seen that with the increase of crushing strength, the content of damaged starch is on the rise, that is, the stronger the crushing strength, the greater the degree of starch damage, which proves that the use of superfine crushing The method can increase the content of damaged starch, increase the degree of starch damage, and achieve the purpose of regulating the degree of starch damage. the

In order to prove that the quality of flour can be improved by regulating the degree of starch damage, the present invention also measures the flour quality characteristics of different crushing degrees, including particle distribution, moisture content, ash content, falling number, sedimentation number, wet gluten content and gluten index of flour, The flour properties of the dough and the fermentation properties of the dough showed that 90% of the unground flour had a particle size of less than 145.08 μm, with an average value of 70.94 μm. After ultrafine grinding with a power of 45Hz, the particle size of the flour changed greatly, more large particles turned into small particles, 90% of the particles were smaller than 81.63μm, and the average particle size was 40.05μm. When the crushing strength continued to increase, the flour particle size continued to decrease, and 50% of the particles were smaller than 25.07μm. When the crushing intensity increases to 100Hz and 130Hz, the particle size is finer than that of the 70Hz sample, but the decreasing trend slows down. The average particle size of the sample is 21.00μm and 14.77μm respectively. Chemicalization has achieved very good results, and this stage has tended to crush the balance zone. According to the characteristics of the particle size distribution above, it can be considered that the particle size of the flour particles is greatly affected from the 45Hz superfine grinding treatment of flour, and the particle size is further reduced by the 100Hz and 130Hz grinding treatment, but the reduction trend slows down. The ash content of flour with different damage degrees is very similar, and the falling number of flour has a significant negative correlation with the damaged starch content in flour, that is, the smaller the falling number of flour, the more damaged starch content; the falling number of flour increases with the increase of damaged starch content. And it increased rapidly, the sedimentation value of flour with damaged starch content of 6.54% was 35.30ml, and the sedimentation value of flour with damaged starch content of 12.06% was 81.60ml. The flour quality test of wheat flour with different damaged starch content shows that the degree of starch damage is positively correlated with the water absorption of flour, and the main reason for the increase of flour water absorption caused by the increase of starch mechanical damage is that The crystalline regions are broken up so that water molecules can enter the entire starch granule. When the flour is not pulverized, the dough formation time is short and the flour quality index is not high. Once the flour is pulverized, the dough formation time increases sharply, and the flour quality index also increases. However, with the increase of the pulverization intensity, the dough The lump forming time and farinograph index remained basically unchanged. The leavening properties of the dough have a very important influence on the quality of the final product. The final fermentation time of the dough indicates the time required to reach the best fermentation state. Fermentation-resistant flour has a longer fermentation stability. The dough level is the volume of the dough when the dough reaches the best fermentation state. Elasticity is the maximum of the curve in the peak area. width. Dough fermentation stability and dough level can be used to comprehensively evaluate the fermentation characteristics of dough. Flour with different damaged starch content has different fermentation characteristics, and the final fermentation time of the dough decreases sharply when the damaged starch content exceeds 7.30%. Resistance to fermentation. When the damaged starch content is 12.06%, the fermentation stability of the dough is poor, that is, the flour is not resistant to fermentation. It can be seen from the above that the fermentation stability of the dough shows a decreasing trend with the increase of the starch damage content. Generally, it showed an increasing trend with the increase of damaged starch content. Flour that is resistant to fermentation is more suitable for making fermented noodle foods such as steamed buns because of its better gas holding capacity, while flour that is not resistant to fermentation is more suitable for making non-fermented noodle foods such as noodles, so as to achieve the goal of controlling the temperature by using ultrafine pulverization. Damage starch content, the purpose of producing special flour. Based on various quality research indicators, it is found that flour with a damaged starch content of less than 6% is suitable for making biscuit noodles and non-fermented flour products, and flour with a damaged starch content of 7%-9% is suitable for steamed bread products, while the damaged starch content is 9%. Between -12% are suitable for the production of bakery products. the

The present invention selects high-quality wheat varieties from Henan for research; the instruments used are: SKCS4100 single-grain grain measuring instrument is a product of Perten, Sweden; the Buhler experimental mill is a product of Buhler, Switzerland; Perten2100 type gluten meter is a product of Perten, Sweden ; The 1800 Falling Number Instrument is a product of Falling Number Company in Sweden; the Brabender Farinograph is a product of Brabender Company in Germany; The product of the special company; the ultraviolet spectrophotometer is the product of Unocal Company of the United States; the ultrafine pulverizer is the product of China Jinke Pulverizing Machinery Co., Ltd. the

Below in conjunction with specific mode, the present invention will be further described:

1. Determination of wheat grain characteristics

The present invention adopts the SKCS4100 system of Swedish Perton Company to measure the characteristics of 300 wheat grains in 3-4 minutes, and then carry out statistical analysis, which can display the average value, standard deviation and draw a histogram, and can simultaneously obtain grain moisture , hardness index, grain quality, grain diameter and other indicators. The results are shown in Table 1. the

Table 1 Test results of wheat grain characteristics

The United States divides soft and hard wheat according to SKCS: SKCS>90 is super hard wheat, 81-90 is very hard, 65-80 is hard wheat, 45-64 is medium hard, 35-44 is medium soft, and 25-34 is medium hard. For soft wheat, 10-24 is very soft, and <10 is super soft. The wheat grain hardness is 67.73, which is durum wheat. The single grain weight of the grain is 41.63mg, and the grain diameter is 3.06mm. the

2. Milling

Use BUHLER experimental milling, refer to AACC method 26-20, determine the amount of water to be moistened according to the hardness of the grain, the moisture content of hard wheat is 16%, the time of moistening is 24h, the average feeding speed of the mill is 100g/min, for 6kg Wheat grains were milled, and the experimental results are shown in Table 2. the

Table 2 Experimental milling results of wheat

3. Superfine grinding

Put the flour obtained by the test mill into the ultrafine pulverizer respectively, and pulverize them with powers of 45Hz, 70Hz, 100Hz, and 130Hz respectively to obtain ultrafine pulverized flour samples. Each flour with different pulverization strengths weighs 800g. During the sample process, it was found that the stronger the crushing strength, the longer the time required for crushing, and with the increase of the crushing strength, the loss rate of flour will also increase. the

4. Determination of damaged starch content and distribution of wheat flour particles

The damaged starch content was measured by AACC 76-31 method, and the flour particle size was measured by laser diffraction particle size analyzer. Table 3 shows the results of damaged starch content and particle size distribution of wheat flour obtained by different crushing intensities. the

Table 3 Particle size distribution and damaged starch content of wheat flour

Note: D10, D50, and D90 respectively indicate that 10%, 50%, and 90% of the particle diameters are smaller than this value on the particle size cumulative distribution curve. the

The data in Table 3 show that 90% of the unmilled flour has a particle size smaller than 145.08 μm, with an average of 70.94 μm. After ultrafine grinding with a power of 45Hz, the particle size of the flour changed greatly, more large particles turned into small particles, 90% of the particles were smaller than 81.63μm, and the average particle size was 40.05μm. When the crushing strength continued to increase, the flour particle size continued to decrease, and 50% of the particles were smaller than 25.07μm. When the crushing intensity increases to 100Hz and 130Hz, the particle size is finer than that of the 70Hz sample, but the decreasing trend slows down. The average particle size of the sample is 21.00μm and 14.77μm respectively. Chemicalization has achieved very good results, and this stage has tended to crush the balance zone. According to the characteristics of the particle size distribution above, it can be considered that the particle size of the flour particles is greatly affected from the 45Hz superfine grinding treatment of flour, and the particle size is further reduced by the 100Hz and 130Hz grinding treatment, but the reduction trend slows down. the

During the superfine grinding process of flour, when the crushing force is strong enough and the force acts rapidly, the instantaneous stress of the flour particles exceeds its mechanical strength, and the relatively smooth surface of the particles becomes rough, and even cracks and cracks appear. Crushing, so that the volume of flour particles is significantly reduced. During this process, the surface properties of flour granules change, and there will also be granule lattice distortion and crystalline transformation, which will transform the crystalline starch granules into an amorphous form, and increase the damage content in the flour. The damaged starch content of unground flour is 6.54%. After the crushing process with an intensity of 45Hz, the damaged starch content is 7.30%. When the crushing intensity is 130Hz, the damaged starch content is 12.06%. Compared with , it has increased by about one time. It can be seen that with the increase of crushing strength, the content of damaged starch is on the rise, that is, the stronger the crushing strength, the greater the degree of starch damage. the

5. Determination of basic quality indicators of wheat flour

The basic quality indexes of the flour treated with different crushing intensities were determined, mainly the moisture content, ash content, falling number, sedimentation number, wet gluten content and gluten index of the flour. The settlement value is determined by AACC 56-61 method; the falling value is determined by AACC 56-81B method. Flour particle size was determined by laser diffraction particle size analyzer. Flour gluten was determined by the Gluten Index instrument of Sweden Perton Company. Including 2200 type gluten meter and 2015 type centrifuge. Wet gluten content is measured according to GB/T14608-93, and the result is converted into 14% wet basis. When performing the measurement, each sample was tested twice in parallel, and the average value was taken as the test value of the sample. The measurement results are shown in Table 4. the

Table 4 Determination results of basic quality of flour with different crushing intensities

From the results in Table 4, it can be seen that the ash content of flour with different damage degrees is very similar, and the falling number of flour is significantly negatively correlated with the damaged starch content in flour, that is, the smaller the falling number of flour, the more damaged starch content, leading to this phenomenon The reason may be that after the starch granules are damaged, they are more sensitive to enzyme reactions and are more likely to be attacked by enzymes and be hydrolyzed into oligosaccharides, thereby reducing the viscosity of the system and decreasing the falling number; With the increase of the damaged starch content, it increases rapidly. The sedimentation value of the flour with the damaged starch content of 6.54% is 35.30ml, and the sedimentation value of the flour with the damaged starch content of 12.06% is 81.60ml; the gluten in the flour is mainly composed of glutenin and alcohol soluble It is formed by protein complexation, and its quantity is not directly related to the content of damaged starch. However, in the process of washing gluten, it was found that with the increase of crushing strength, the extensibility of gluten decreased, and the gluten of wheat flour treated at 130 Hz was almost non-existent. Extensibility. the

6. Determination of flour quality of wheat flour

The flour quality of wheat flour is determined by GB/T 14614-93 method. the

The farinity test was carried out on wheat flour with different damaged starch contents, and the test results are shown in Table 5. It can be seen from the measurement results that the degree of starch damage is positively correlated with the water absorption of flour, and the main reason for the increase in flour water absorption caused by the increase of starch mechanical damage is that when the starch granules are damaged, the crystal region is broken, so that water molecules can enter to the entire starch granule. It can also be seen from Table 5 that when the flour is not pulverized, the dough formation time is short and the farinity quality index is not high. Dough development time and farinograph index remained basically unchanged with the increase of pulverization intensity. When the content of damaged starch was between 6.54% and 9.66%, the stability time of flour did not change much, and when the content of damaged starch increased to 12.06%, the water absorption of flour increased greatly. the

Table 5 Determination Results of Dough Flour Quality Parameters

7. Determination of dough fermentation characteristics

The method for measuring dough fermentation characteristics is: flour 300g (14.0% water basis), yeast (common yeast) 3%, salt 2%, sugar 1%, dissolve with 24ml distilled water 15 minutes before starting to prepare dough, put it into the proofing room of maturity instrument warm up. Pour the flour into the kneading bowl of the farinograph, then pour in the yeast solution and salt water (pre-dissolved), start the farinograph and stir the dough until the dough is formed (the shortest time is 4 minutes, the longest time is 15 minutes), and the final consistency should be (500±20 )FU. Divide the prepared dough into two pieces, about 155g each, put them into the proofing room of the maturity curve instrument for fermentation, and the time interval is 35-15-30min. It is 15r/min. After the last fermentation is over, accurately weigh 150g of dough, shape it into a rounder, put the dough into the plastic bowl equipped with the needle eye down, cover with a layer of plastic film, flatten the dough with a punching device, and put it into the magnetic bowl in the fermentation room. On the support, adjust the recording pen to the zero line, turn on the switch, the measurement starts, and the maturity curve of the dough will be recorded. The results of the dough fermentation characteristics are shown in Table 6. the

Table 6 Dough Fermentation Characteristic Determination Result

The leavening properties of the dough have a very important influence on the quality of the final product. The final fermentation time of the dough indicates the time required to reach the best fermentation state. Fermentation-resistant flour has a longer fermentation stability. The dough level is the volume of the dough when the dough reaches the best fermentation state. Elasticity is the maximum of the curve in the peak area. width. Dough fermentation stability and dough level can be used to comprehensively evaluate the fermentation characteristics of dough. Table 6 shows the fermentation test results of wheat flour with different crushing intensities. It can be seen from Table 6 that flour with different damaged starch contents has different fermentation characteristics. When the crushing power is at 0 Hz and 45 Hz, the damaged starch content is 6.54%. When the damaged starch content is 12.06%, the fermentation volume of the dough is larger. the

In summary, the content of damaged starch in flour can be regulated by ultrafine pulverization, so as to meet the needs of different flour products. The present invention adopts 45-130 Hz power ultrafine pulverization to produce flour with a damaged starch content of 7.30-12.06%, which is suitable for processing requirements of different flour products. The wheat raw material adopted in the present invention is hard wheat, and based on the same invention principle, the present invention is also applicable to other wheat species, such as soft wheat and medium hard wheat. In the same way, the superfine grinding power can be adjusted in a wider range to obtain special flour with a wider range of damaged starch content, which can meet the needs of wheat flour processing enterprises for product segmentation. the

The invention can increase the content of damaged starch in the wheat flour by ultrafine pulverizing the wheat flour obtained by conventional grinding, thereby improving the quality of the flour and meeting the needs of flour product processing. After the invention is implemented in wheat processing enterprises, it can produce wheat special flour with higher content of damaged starch, which has important practical significance and broad application prospects for the development of high-tech industries. the

The above examples are only used to illustrate preferred implementations of the present invention, but the present invention is not limited to the above-mentioned implementations, within the scope of knowledge possessed by those of ordinary skill in the art, any modifications made within the spirit and principles of the present invention , equivalent replacements and improvements, etc., all of which shall be covered within the scope of the technical solution claimed in the present invention. the

Claims (4)

1. A method for improving flour quality by regulating and controlling wheat starch damage degree is characterized in that: the wheat is pulverized through an ultrafine pulverizer after conventional grinding. 2. A method for improving flour quality by regulating the degree of damage of wheat starch according to claim 1, characterized in that: the pulverization power used during ultrafine pulverization is 45-130 Hz. 3. A method for improving flour quality by regulating the degree of wheat starch damage according to claim 2, characterized in that: the content of damaged starch in the flour obtained by superfine grinding is in the range of 7.30% to 12.06%. 4. A method for improving flour quality by adjusting and controlling the degree of wheat starch damage according to claim 2, characterized in that: the content of damaged starch in the flour obtained by superfine grinding is 12.06%.