Optimization method of rapeseed meal treatment process capable of improving nutritional value, treatment process and rapeseed meal treatment product

Abstract

The invention belongs to the technical field of animal feed processing and preparation, and particularly relates to an optimization method of a rapeseed meal treatment process capable of improving nutritional value, the treatment process and a rapeseed meal treatment product. The optimization method comprises the following steps: designing an orthogonal test of the puffed rapeseed meal and carrying out a corresponding orthogonal test according to orthogonal test factors to obtain an optimal parameter combination of the influence factors; processing the rapeseed dregs according to the optimal parameters, and exploring the change of each component of the rapeseed dregs before and after puffing; and processing the rapeseed dregs according to the optimal parameters, and exploring the change of the microstructure and the protein secondary structure of the rapeseed dregs before and after puffing. The glucosinolate, phytic acid, crude fiber content and crude protein in-vitro digestibility are used as evaluation indexes, the treatment effect of the puffing process on the rapeseed dregs is explored, the treatment process of the rapeseed dregs is further optimized through tests, treatment products related to the rapeseed dregs are enriched, and the nutritional value and comprehensive utilization degree of the rapeseed dregs are improved.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of animal feed processing and preparation, and particularly relates to an optimization method of a rapeseed meal processing technology capable of improving nutritional value, a processing technology and a rapeseed meal processing product. BACKGROUND

[0003] Rapeseed meal has been a research object for replacing soybean meal, and has its unique advantages. The protein content of rapeseed meal is comparable to that of soybean meal, and rapeseed meal is also rich in sulfur-containing amino acids and has a reasonable amino acid composition, thus having a wide application potential. However, the anti-nutritional factors (glucosinolates, phytic acid, etc.) present in rapeseed meal have a negative impact on feed digestibility and animal health, and limit the proportion of rapeseed meal for replacing soybean meal.

[0004] Feed pre-digestion technology is a new type of feed processing technology for specific pre-digestion treatment of feed, which can reduce the content of anti-nutritional factors in feed, increase the digestion and absorption of feed by livestock and poultry, and improve the conversion efficiency of feed. Current pre-digestion technologies mainly include three types, i.e., microbial pre-digestion technology, chemical pre-digestion technology and physical pre-digestion technology. The microbial pre-digestion technology can decompose phytic acid, crude fiber and anti-nutritional factors in feed raw materials, improve the palatability of feed, increase the digestibility and utilization rate, and enhance the immunity of animals. The chemical pre-digestion technology is a pre-digestion method for treating feed raw materials by using chemical reagents such as acid and alkali, including alkali treatment, ammoniation treatment, oxidation treatment and the like. The physical pre-digestion technology is a pre-treatment method for feed raw materials by using physical actions such as water, heat and machinery, such as shortening, powdering, removing impurities, steam pelleting, puffing, steaming, microwave heating and the like. Among them, the physical pre-digestion method has the characteristics of short processing time, high efficiency and no environmental pollution, thus having a wide application prospect.

[0005] At present, there are few researches on the physical processing technology of rapeseed meal, and the physical processing mainly adopts heat treatment method. However, improper high-temperature treatment can denature rapeseed protein, reduce the content of amino acids, and affect other bioactive substances. SUMMARY

[0006] In view of the deficiencies of the prior art, the present application aims to provide an optimization method of a rapeseed meal processing technology capable of improving nutritional value, a processing technology and a rapeseed meal processing product, so as to improve the nutritional value of rapeseed meal and make it a feasible raw material for replacing soybean meal.

[0007] The extrusion puffing technology in the prior art still has some problems, such as that the quality of the puffed product is not only affected by the feed raw material but also by the process parameters, and the mechanism of action on the material is relatively vague. Therefore, appropriate processing parameters are particularly important. However, there are few research reports on puffed rapeseed meal in China at present, and there are insufficient process parameters for reference, which limits the utilization of the puffed processing product in livestock and poultry breeding.

[0008] To achieve the above object, the technical scheme adopted by the present application is as follows: An optimization method of a rapeseed meal processing technology capable of improving nutritional value, the optimization method comprising:

[0009] A. designing an orthogonal test of puffed rapeseed meal and performing a corresponding orthogonal test according to the factors of the orthogonal test to obtain an optimal parameter combination of the factors;

[0010] B. processing rapeseed meal according to the optimal parameters to explore the changes of various components of the rapeseed meal before and after puffing;

[0011] C. processing rapeseed meal according to the optimal parameters to explore the changes of microstructure and protein secondary structure of the rapeseed meal before and after puffing.

[0012] In a preferred embodiment, the various components of the rapeseed meal include glucosinolate, phytic acid, crude fiber and crude protein; and the optimization method uses the contents of glucosinolate, phytic acid and crude fiber in the rapeseed meal and the in vitro digestion rate of crude protein as evaluation indexes.

[0013] Further, the factors include the water content of the rapeseed meal, the extrusion puffing temperature and the screw rotation speed.

[0014] Preferably, the orthogonal test is a three-factor three-level orthogonal test.

[0015] Preferably, the three-factor three-level orthogonal test specifically comprises:

[0016] The first factor: the water content of the rapeseed meal, which is set to have three levels of 18%, 20% and 22%;

[0017] The second factor: the extrusion puffing temperature, which is set to have three levels of 100℃, 120℃ and 140℃;

[0018] The third factor: the screw rotation speed, which is set to have three levels of 180 r / min, 220 r / min and 260 r / min.

[0019] Another object of the present application is to disclose a rapeseed meal processing technology capable of improving nutritional value, which is to take crushed and sieved rapeseed meal, adjust the water content of the rapeseed meal to 18% to 22%, and perform extrusion puffing at a screw rotation speed of 180 to 260 r / min and a temperature of 100 to 140℃.

[0020] Further, by using the optimization method described above, it is concluded through orthogonal test and evaluation index analysis that the optimal process parameter combination for processing rapeseed meal is to have a water content of 22%, a screw rotation speed of 220 r / min and an extrusion puffing temperature of 120℃.

[0021] A further object of the present application is to provide rapeseed meal treatment products obtained by the aforementioned rapeseed meal treatment process.

[0022] Preferably, the rapeseed meal treatment product has a crude fiber content of 12.40%, a glucosinolate content of 2.30 μmol / g, a phytic acid content of 43.16 mg / g, and a crude protein in vitro digestibility of 62.17%.

[0023] Further, the surface of the rapeseed meal becomes loose and porous and the secondary structure changes after the expansion treatment.

[0024] The present application has the advantages that the present application provides an optimization method, a treatment process, and a rapeseed meal treatment product of a rapeseed meal treatment process capable of improving nutritional value. The glucosinolate content, the phytic acid content, the crude fiber content, and the crude protein in vitro digestibility are used as evaluation indexes to explore the effect of the expansion process on the treatment of rapeseed meal. A rapeseed meal treatment process is further optimized through experiments, which enriches the related treatment products of rapeseed meal and improves the nutritional value and comprehensive utilization of rapeseed meal.

[0025] The method has the advantages of low production cost, simplicity, practicality, strong operability, and good effect, and is suitable for industrial production. The present application successfully makes up for the deficiency of rapeseed meal in the application field of extrusion expansion process. The expanded rapeseed meal obtained by the present application can be used as a source of protein for livestock and poultry and applied in various feed. BRIEF DESCRIPTION OF DRAWINGS

[0026] Figure 1 Scanning electron microscope images of rapeseed meal, A, scale 5 μm; B, scale 20 μm;

[0027] Figure 2 Scanning electron microscope images of expanded rapeseed meal, A, scale 5 μm; B, scale 20 μm;

[0028] Figure 3 Infrared spectrum of rapeseed meal protein;

[0029] Figure 4 Infrared spectrum of expanded rapeseed meal protein;

[0030] Figure 5 Changes in the secondary structure of rapeseed meal protein before and after extrusion expansion (%). DETAILED DESCRIPTION

[0031] The present application provides an optimization method, a treatment process, and a rapeseed meal treatment product of a rapeseed meal treatment process capable of improving nutritional value. To make the objects, technical solutions, and effects of the present application clearer and more explicit, the following embodiments further illustrate the present application. It should be understood that the specific embodiments described herein are only used to explain the present application and do not limit the present application.

[0032] An optimization method of a rapeseed meal processing technology capable of improving nutritional value according to embodiments of the present application.

[0033] The optimization method comprises:

[0034] A. designing an orthogonal test of puffed rapeseed meal and performing a corresponding orthogonal test according to factors of the orthogonal test to obtain an optimal parameter combination of the factors;

[0035] B. processing rapeseed meal according to the optimal parameters to explore changes in various components of the rapeseed meal before and after puffing;

[0036] C. processing rapeseed meal according to the optimal parameters to explore changes in microstructure and protein secondary structure of the rapeseed meal before and after puffing.

[0037] Specifically, the factors can include water content of the rapeseed meal, extrusion puffing temperature, screw rotation speed, etc.

[0038] The optimization method uses in vitro protein digestion rate of rapeseed meal, crude fiber, glucosinolate and phytic acid content as evaluation indexes.

[0039] According to the orthogonal test conditions, a corresponding orthogonal test is performed and various evaluation indexes are analyzed to obtain the optimal parameter combination of the factors.

[0040] The rapeseed meal and the puffed rapeseed meal are observed for microstructure changes by scanning electron microscopy.

[0041] The rapeseed meal and the puffed rapeseed meal are analyzed for protein secondary structure changes by Fourier infrared spectroscopy.

[0042] Specifically, the orthogonal test corresponding to the above factors is set as a three-factor three-level orthogonal test.

[0043] The three-factor three-level orthogonal test specifically comprises:

[0044] The first factor: water content of the rapeseed meal, which is set to have three levels of 18%, 20%, and 22%.

[0045] The second factor: extrusion puffing temperature, which is set to have three levels of 100℃, 120℃, and 140℃.

[0046] The third factor: screw rotation speed, which is set to have three levels of 180 r / min, 220 r / min, and 260 r / min.

[0047] The influencing factors selected above are factors that have greater influence on the effect of the extrusion puffing process. The orthogonal test conditions and evaluation indexes described above can well evaluate the influence of each influencing factor on the final effect of the extrusion puffing process, and better optimization effect can be obtained.

[0048] The optimized process is simple and feasible, fast in processing speed, high in efficiency, green and environmentally friendly, and the content of various anti-nutritional factors in the treated product is reduced and the protein digestion rate is improved, which is suitable for application in enterprise scale production and has good prospects.

[0049] Example 1: Adjustment of moisture content of rapeseed meal

[0050] Take 1000 g of crushed and sieved rapeseed meal (purchased from Nanjing Tejieli Planting Professional Cooperative, moisture content is 10.3933%, 10.3933% is mass fraction) in three parts, and adjust the moisture content to 18%, 20% and 22% (mass fraction). The specific operation is as follows: for 18% moisture content, take 915.08 g of crushed rapeseed meal, add 84.92 g of ultrapure water, mix well in a self-sealing bag, and then place it in a 4°C refrigerator overnight; for 20% moisture content, take 892.76 g of crushed rapeseed meal, add 107.24 g of ultrapure water, mix well in a self-sealing bag, and then place it in a 4°C refrigerator overnight; for 22% moisture content, take 870.44 g of crushed rapeseed meal, add 129.56 g of ultrapure water, mix well in a self-sealing bag, and then place it in a 4°C refrigerator overnight. Mix well again before feeding into the puffing machine.

[0051] Example 2: Orthogonal test of puffed rapeseed meal

[0052] A 3-factor 3-level orthogonal test is designed by SPSS software, the test factor level table is shown in Table 1, and the L9(3 3 ) orthogonal table is shown in Table 2.

[0053] The extrusion puffing machine used is a DS 32 type double screw test machine (Jinan Saixin Puffing Machinery Co., Ltd.). According to the orthogonal test design table, the test is arranged, the material is prepared according to the set conditions, the feeder is filled with material, the temperature is set, the temperature of the first zone of the puffing cavity sleeve is set to 50°C, the temperature of the second zone is set to 70°C, and the temperature of the third zone is set according to the test conditions (the temperatures of the first and second zones remain unchanged). When the temperature of the third zone rises to about 90°C, start the main machine with a speed setting of 120 r / min, then open the feeder, and when the machine runs stably and can stably discharge, adjust the extrusion puffing temperature and screw speed to the corresponding test values in Table 2, and then take samples when the actual values of each parameter displayed by the machine instrument reach the preset test values. Then adjust each parameter according to the corresponding test values in Table 2 and take samples, and repeat in turn until all parameter combinations are completed.

[0054] According to Table 2, different moisture content of rapeseed meal was put into the extrusion machine with parameters set, and after the machine processing, the expanded rapeseed meal treated by different processing parameters was obtained.

[0055] Test index determination method:

[0056] (1) Determination of crude protein: The samples before and after expansion were placed in a digestion tube, mixed catalyst and concentrated sulfuric acid were added, and the digestion was carried out on a digestion furnace at 420℃ until the solution showed transparent blue-green color. After cooling to room temperature, the samples were put into a Kjeldahl nitrogen determination instrument for automatic analysis.

[0057] (2) Determination of crude fiber: The samples before and after expansion were put into filter bags and sealed, and then sulfuric acid solution and sodium hydroxide solution were poured into the semi-automatic fiber analyzer for digestion. After digestion, the samples were soaked in acetone and dried, and then weighed and calculated the content of crude fiber.

[0058] (3) Determination of in vitro protein digestibility: The three-dimensional digestion procedure of pepsin-trypsin complex treatment method was used, and the specific operation was referred to Wang Weiguo (2000).

[0059] (4) Determination of glucosinolates: 0.1 g of the samples before and after expansion was taken into a 10 ml centrifuge tube, boiled in a water bath, and then steamed for 10 min. About 8 ml of hot water at 90℃ was added, and the sample was boiled in water bath for 20-40 min. After cooling, the sample was diluted with water to 10 ml, shaken well, filtered, and then 0.1% carboxymethylcellulose sodium solution and palladium chloride color developing solution were added. The extinction value was measured in a spectrophotometer, and the specific operation was referred to Wang Ninghui (2009) method.

[0060] Conversion formula: Total amount of glucosinolates = 185.2 x extinction value + 0.2

[0061] (5) Determination of phytic acid: The phytic acid content of the samples before and after expansion was determined by using a related kit (purchased from Suzhou Greiss Biological Technology Co., Ltd.) and microplate method, and the specific operation was carried out according to the instruction manual.

[0062] Table 1 Test factor level table

[0063]

[0064] Table 2 Orthogonal table of different extrusion expansion process conditions

[0065]

[0066]

[0067] The results of Table 3 and Table 4 show that the combination of different processing parameters has a significant effect on the crude protein, crude fiber, glucosinolate, phytic acid content and in vitro digestibility of the expanded rapeseed meal; the total ranking of the effect of each component of the expanded rapeseed meal is B > A > C, i.e. material moisture > expansion temperature > screw speed; the optimal level of each group is counted, and the optimal level of A group (expansion temperature) is A2 (120°C); the optimal level of B group (material moisture) is B3 (22%); the optimal level of C group (screw speed) is C2 (220 r / min). The final optimal level is A2 B3 C2, i.e. expansion temperature 120°C, material moisture 22%, and screw speed 220 r / min.

[0068] Table 3 Extrusion expansion process parameters L9(3 3 )orthogonal design test results

[0069]

[0070] Table 4 Extrusion expansion process parameters L9(3 3 )orthogonal design range analysis

[0071]

[0072]

[0073] The changes of the components of the rapeseed meal under the optimal expansion conditions are shown in Table 5, and the results show that, compared with the untreated rapeseed meal, the in vitro crude protein digestibility of the expanded rapeseed meal is significantly improved, and the contents of the anti-nutritional factors glucosinolate, phytic acid and crude fiber are significantly reduced.

[0074] Table 5 Changes of each component of the rapeseed meal and in vitro protein digestibility before and after expansion

[0075]

[0076] The process parameters of the extrusion expansion rapeseed meal are optimized in the scheme, and the optimal process parameters are: expansion temperature 120°C, material moisture 22%, and screw speed 220 r / min. Using the extrusion expansion process can significantly improve the in vitro crude protein digestibility of the rapeseed meal, and significantly reduce the contents of the anti-nutritional factors glucosinolate, phytic acid and crude fiber.

[0077] Example 3: Changes of protein secondary structure and microstructure of the expanded rapeseed meal

[0078] One portion of the crushed and sieved rapeseed meal and one portion of the expanded rapeseed meal are taken and dried to absolute dryness in an oven. The observation sample is stuck to the sample stage using double-sided tape, the observation surface is upward, the surface of the sample to be observed is coated with a 10 nm gold film using an ion sputtering instrument, and the surface is observed and photographed using a scanning electron microscope (Hitachi SU8010).

[0079] By Figure 1 It can be seen that the non-extruded and expanded rapeseed meal is in close and orderly combination state, and the surface is smooth. Figure 2 It can be seen that the surface of the rapeseed meal becomes loose and porous after the extrusion and expansion treatment, and obvious fibrous and continuous surface texture features are formed around the rapeseed meal, and the rapeseed meal has a porous fiber structure.

[0080] About 2 mg of the sample was ground and diluted with KBr at a ratio of 1 to 100, and then tabletting was performed, the infrared spectrum was collected with air as the background, and the scanning wave number range was 400-4000 cm -1 , the resolution was 4 cm -1 , and the scanning was 32 times. OmnicV6.2 and PeakfitV4.12 software were used for data preprocessing and Gaussian peak fitting processing, respectively.

[0081] By Figure 3 , Figure 4 It can be seen that the Fourier infrared spectrum of the rapeseed meal protein before and after expansion has no great difference. Figure 5 It can be seen that the secondary structure of the rapeseed meal protein changes before and after expansion, mainly in that the ratio of alpha-helix shows an upward trend, the ratio of random coil shows an upward trend, and the ratio of beta-fold shows a downward trend.

[0082] The extrusion and expansion process of the rapeseed meal is optimized by adopting an orthogonal test design, the processing factors that have a greater influence on the extrusion and expansion process, i.e., extrusion and expansion temperature, material moisture and screw rotation speed, are selected, three gradients of each influencing factor are selected, finally, the best process parameter combination is selected through orthogonal combination and combination of various evaluation indexes. The influence of various processing parameter combinations on the processing product can be compared more carefully through the design method of the orthogonal test, and the processing parameter combination of the previous extrusion and expansion process is more convincing, and ideas are provided for the standardization of the extrusion and expansion process of the rapeseed meal.

[0083] The rapeseed meal is processed by adopting a dry extrusion and expansion method, compared with a wet extrusion and expansion method, only the moisture of the rapeseed meal needs to be adjusted before extrusion and expansion, and the processing is more simple and easy to operate, the requirement for equipment is lower, and the processing effect is good.

[0084] In the extrusion and expansion process of the rapeseed meal, the rapeseed meal stays in the extrusion and expansion cavity for a short time, the protein and amino acid contents in the rapeseed meal are greatly retained, the in-vitro crude protein digestion rate of the processing product is improved, and the contents of the anti-nutritional factors, glucosinolate and phytic acid, in the rapeseed meal are effectively reduced.

[0085] The application enriches rapeseed meal related processing products, improves the nutritional value and comprehensive utilization degree of rapeseed meal, and has the advantages of low production cost, simplicity, practicality, strong operability, good treatment effect and the like, and is suitable for industrialized production. The expanded rapeseed meal obtained by the application can be applied to various feed rations as a source of poultry protein.

[0086] The above examples are only used to illustrate the technical solutions of the application, and those skilled in the art should understand that the above examples do not limit the application in any form, and any technical solutions obtained by equivalent replacement or equivalent transformation fall within the protection scope of the application.

Claims

1. A method for optimizing the process of processing rapeseed meal to improve its nutritional value, characterized in that, The optimization method comprises: A. Designing an orthogonal test of puffed rapeseed meal and performing a corresponding orthogonal test according to factors of the orthogonal test to obtain an optimal parameter combination of the factors; B. Processing the rapeseed meal according to the optimal parameters to explore changes in various components of the rapeseed meal before and after puffing; C. Processing the rapeseed meal according to the optimal parameters to explore changes in the microstructure and protein secondary structure of the rapeseed meal before and after puffing.

2. The process for optimizing the process for improving the nutritional value of rapeseed meal according to claim 1, characterized in that, The various components of the rapeseed meal include glucosinolate, phytic acid, crude fiber and crude protein; the optimization method uses the glucosinolate, phytic acid, crude fiber content and in vitro digestibility of crude protein in the rapeseed meal as evaluation indexes.

3. The process for optimizing the process for improving the nutritional value of rapeseed meal according to claim 1, characterized in that, The factors include the water content of the rapeseed meal, the extrusion puffing temperature and the screw rotation speed.

4. The process for optimizing the process for improving the nutritional value of rapeseed meal according to claim 1, characterized in that, The orthogonal test is a three-factor three-level orthogonal test.

5. The process for optimizing the process for improving the nutritional value of rapeseed meal according to claim 1, characterized in that, The three-factor three-level orthogonal test specifically comprises: The first factor: the water content of the rapeseed meal, which is set to have three levels of 18%, 20% and 22%; The second factor: the extrusion puffing temperature, which is set to have three levels of 100°C, 120°C and 140°C; The third factor: the screw rotation speed, which is set to have three levels of 180 r / min, 220 r / min and 260 r / min.

6. A process for the treatment of rapeseed meal to improve its nutritional value, characterized in that: The crushed and sieved rapeseed meal is adjusted to have a water content of 18%-22%, and is subjected to extrusion puffing at a screw rotation speed of 180-260 r / min and a temperature of 100-140°C.

7. A process for the treatment of rapeseed meal to improve its nutritional value according to claim 6, wherein, According to the optimization method of any one of claims 1-5, through orthogonal test and evaluation index analysis, it is concluded that the optimal process parameter combination for processing the rapeseed meal is a water content of 22%, a screw rotation speed of 220 r / min and an extrusion puffing temperature of 120°C.

8. A rapeseed meal processing product obtained by the rapeseed meal processing process of claim 6 or 7.

9. The rapeseed meal treatment product according to claim 8, characterized in that, The rapeseed meal processing product has a crude fiber content of 12.40%, a glucosinolate content of 2.30 μmol / g, a phytic acid content of 43.16 mg / g and an in vitro digestibility of crude protein of 62.17%.

10. Rapeseed meal treatment product obtained by applying the rapeseed meal treatment process according to claim 6 or 7, characterized in that, After the puffing treatment, the surface of the rapeseed meal becomes loose and porous, and the protein secondary structure changes.

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