Method for comprehensively utilizing rapeseeds

Abstract

The invention discloses a comprehensive utilization method of rapeseeds. The method comprises the following steps: carrying out moisture regulation treatment on the rapeseeds; carrying out pulsed electric field-radio frequency combined treatment on the rapeseeds; peeling the pretreated rapeseeds to obtain rapeseed kernels and rapeseed peels, and utilizing the rapeseed peels to obtain rapeseed peel microcrystalline cellulose; carrying out superfine grinding on the rapeseed kernels to obtain oil extraction raw material rapeseed kernel powder; soaking the rapeseed kernel powder in a solvent; low-intensity alternating magnetic field-ultrasonic microwave synergistic extraction is adopted; centrifugally separating the extracted mixed solution to obtain rapeseed oil and rapeseed meal; putting the rapeseed dregs into an irradiation device, and carrying out irradiation treatment at room temperature; adding an isopropyl alcohol aqueous solution into the radiated rapeseed meal for washing, and separating to obtain crude rapeseed meal protein; and adding a methanol aqueous solution into the crude rapeseed meal protein, pre-homogenizing, putting into a high-pressure micro-jet homogenizer, carrying out dynamic ultrahigh-pressure micro-jet treatment, and carrying out vacuum filtration, ultrafiltration purification and freeze drying to obtain the refined rapeseed meal protein.

Description

Technical Field

[0001] The invention belongs to the technical field of oil processing, and in particular relates to a method for comprehensive utilization of rapeseed. Background Art

[0002] The traditional rapeseed processing method is mainly to extract oil through pressing. Although the process is simple, it has many shortcomings, such as low oil yield, high labor intensity, low production efficiency, and protein denaturation in rapeseed meal due to embryo rolling and steaming, which makes the overall utilization rate low.

[0003] The seed coat in rapeseed accounts for about 14% to 18% of the dry weight of the seed, and contains a large amount of crude fiber (accounting for 40%-48%), as well as anti-nutrients such as pigments, phytic acid and tannins. Although the oil yield will be slightly reduced when the rapeseed is pressed after dehulling (because the oil content of the seed coat itself is about 6%-14%), this pretreatment step fundamentally removes most of the pigments and anti-nutrients in the rapeseed, preventing them from being mixed into the oil during subsequent processing. This not only produces higher quality rapeseed oil, but also increases the utilization value of rapeseed protein and reduces energy consumption in the refining process. With the popularization of dehulling technology, rapeseed hulls have become the second largest by-product in the rapeseed oil processing process, second only to rapeseed meal.

[0004] Therefore, as the main by-products in the rapeseed oil processing process, the high-value utilization of rapeseed meal and rapeseed husk is particularly important and has become the key to the effective comprehensive utilization of rapeseed. Rapeseed meal is rich in protein, with a content of generally 35-45%, and a balanced amino acid composition. It is a high-quality plant protein resource. The development and utilization of rapeseed meal protein has significant economic and social benefits. At present, high-purity rapeseed protein can be effectively extracted through biological fermentation, enzymatic hydrolysis and membrane separation, but the process is complicated and the cost is high. Rapeseed husk, as an agricultural waste, is usually treated as fuel, but its actual value has not been fully utilized. Summary of the invention

[0005] In view of the shortcomings of the existing technology for comprehensive utilization of rapeseed, the present invention provides a method for extracting rapeseed kernel oil assisted by multi-field coupling, and prepares refined rapeseed meal protein by irradiation treatment-alcohol washing and combined high-pressure microfluidization technology on rapeseed meal. At the same time, rapeseed peel is used as raw material to prepare rapeseed peel microcrystalline cellulose by low-temperature extrusion-low eutectic solvent treatment, which is beneficial to the comprehensive utilization of rapeseed.

[0006] In order to achieve the above purpose, the technical solutions adopted are as follows: A method for comprehensive utilization of rapeseed mainly comprises the following steps: (1) Water regulation: adjust the moisture of rapeseed; (2) Pretreatment: Rapeseed is treated with pulsed electric field-radio frequency combination; (3) Peeling: Peeling the pretreated rapeseed to obtain rapeseed kernels and rapeseed husks; (4) Crushing: Ultrafine grinding of rapeseed kernels into rapeseed kernel powder, a raw material for oil extraction; (5) Soaking treatment: soaking the rapeseed kernel powder in a solvent; (6) Oil extraction and separation: low-intensity alternating magnetic field-ultrasonic microwave synergistic extraction; (7) Oil separation: centrifuging the extracted mixed liquid to separate rapeseed oil and rapeseed meal; (8) Irradiation treatment: placing the rapeseed meal in an irradiation device and irradiating it at room temperature; (9) Alcohol washing: adding an isopropanol aqueous solution to the irradiated rapeseed meal for washing to separate and obtain crude rapeseed meal protein; (10) High-pressure microfluidization treatment: A methanol-water solution is added to the crude rapeseed meal protein, which is pre-homogenized in a high-pressure homogenizer and then placed in a high-pressure microfluidizer for dynamic ultrahigh-pressure microfluidization treatment. Refined rapeseed meal protein is obtained after vacuum filtration, ultrafiltration purification, and freeze-drying.

[0007] According to the above scheme, in step (1), the specific method for adjusting the moisture treatment is as follows: distilled water is added to the raw rapeseed, and the raw rapeseed is sealed and allowed to stand at 4°C for more than 12 hours, so that the moisture content in the rapeseed reaches 10-12wt%.

[0008] According to the above scheme, in step (2), the parameters of the pulse electric field treatment are: the distance between the electrodes is 45 mm, the pulse voltage is 15-45 kV, the material residence time is 60-210 s, the pulse frequency is 300-1000 Hz, and the pulse width is 3-10 μs. Preferably, the pulse voltage is 35 kV, the material residence time is 180 s, the pulse frequency is 800 Hz, and the pulse width is 8 μs.

[0009] According to the above scheme, in step (2), the parameters of the radio frequency treatment are: frequency of 27.12 MH, electrode gap of 70 mm, chamber temperature of 80° C., and radio frequency temperature of 100-160° C. Preferably, the radio frequency temperature is 140° C.

[0010] According to the above scheme, in step (3), a rapeseed peeling machine is used to perform peeling treatment to obtain rapeseed kernels and rapeseed peels.

[0011] According to the above scheme, in step (4), the specific method of pulverization is: firstly, the rapeseed kernels are pulverized into a volume average particle size of 180-220 μm by a pulverizer, then pulverized into a volume average particle size of 30-100 μm by a grinder, and finally pulverized into an oil extraction raw material with a volume average particle size of 5-20 μm by an air flow ultrafine pulverizer.

[0012] According to the above scheme, in step (5), the solvent for the soaking treatment is a D-limonene / ethanol solution of ascorbyl palmitate, wherein the concentration of ascorbyl palmitate is 0.1-1.0wt%, and the volume ratio of D-limonene to ethanol is 1:(0.2-2); the solid-liquid ratio of the soaking treatment is 1:(2-8) (g / mL), and the soaking treatment time is 0.5-3.0h.

[0013] Preferably, the concentration of ascorbyl palmitate is 0.5 wt %, the ratio of D-limonene to ethanol is 1:1; the solid-liquid ratio is 1:5 (g / mL), and the soaking time is 2.0 h.

[0014] According to the above scheme, in step (6), the parameters of the low-intensity alternating magnetic field are: magnetic field intensity 20-180 GS, magnetic field treatment time 1-8 hours. Preferably, the magnetic field intensity is 80 GS, and the magnetic field treatment time is 4 hours.

[0015] According to the above scheme, in step (6), the parameters of ultrasonic-microwave synergistic treatment are: ultrasonic power 50-100 W, microwave power 100-500 W, extraction temperature 50-70° C., and extraction time 5-30 min. Preferably, ultrasonic power 70 W, microwave power 300 W, extraction temperature 60° C., and extraction time 15 min.

[0016] According to the above scheme, in step (7), the specific method of separation treatment is: using a centrifuge to perform centrifugal treatment at a speed of 8000r / min for 20min, then removing the solvent by rotary evaporation, and collecting the upper clear oil.

[0017] According to the above scheme, in step (8), the specific method of irradiation treatment is as follows: the rapeseed meal is placed in a metal box of the irradiation device and irradiated at room temperature, and the activity of the radiation source is fixed at 2.96×10 16 Bq, set the irradiation dose parameter to: 200-800 kGy. Preferably, the radiation source activity is fixed at 2.96×10 16 Bq, set the irradiation dose parameter to: 400 kGy.

[0018] According to the above scheme, in step (9), the specific method of alcohol washing is: washing with a 70% (V / V) isopropanol aqueous solution, with a fixed stirring speed of 150r / min; wherein the solid-liquid ratio is 1:4-8, the temperature is 30-60°C, and the time is 20-80min; the solid is separated by centrifugation and freeze-dried to obtain crude rapeseed meal protein. Preferably, the solid-liquid ratio is 1:5, the temperature is 50°C, and the time is 50min.

[0019] According to the above scheme, in step (10), the specific method of high-pressure microfluidization is as follows: 70% (V / V) methanol aqueous solution is added to the crude rapeseed meal protein, with a solid-liquid ratio of 1:4-10, mixed evenly, pre-homogenized in a high-pressure homogenizer, the time is fixed at 30s, the pressure is 10-30Mpa, the number of times is 1-3 times, and then placed in a high-pressure microfluidizer for dynamic ultra-high pressure microfluidization treatment, the time is fixed at 5min, the pressure is 90-130Mpa, and the temperature is 30-60°C. Finally, refined rapeseed meal protein is obtained after vacuum filtration and freeze-drying.

[0020] Preferably, the material-liquid ratio is 1:8, the pre-homogenization time in the high-pressure homogenizer is fixed at 30s, the pressure is 25Mpa, and the number of times is 2 times; the dynamic ultra-high pressure microfluidization treatment time in the high-pressure microfluidizer is fixed at 5min, the pressure is 110Mpa, and the temperature is 40°C. Finally, refined rapeseed meal protein is obtained after vacuum filtration, ultrafiltration purification (10kDa), and freeze-drying.

[0021] According to the above scheme, step 3 also includes utilizing rapeseed peels, including the following steps: S1, defatting: crushing and defatting the rapeseed husk to obtain defatted rapeseed husk powder; S2, low temperature extrusion: the defatted rapeseed hull powder is treated with liquid nitrogen at low temperature and then subjected to twin-screw extrusion; S3, low eutectic solvent treatment: low eutectic solvent treatment is performed on the defatted rapeseed hull powder after low temperature extrusion; S4. Bleaching treatment: After drying, bleaching treatment is performed to obtain rapeseed hull microcrystalline cellulose.

[0022] According to the above scheme, in step S1, the specific method of defatting treatment is: firstly, the rapeseed husk is crushed by a grinder and then passed through an 80-mesh sieve, and then the rapeseed husk is defatted by a Soxhlet extraction method, and then the defatted rapeseed husk powder is obtained by drying after desolventizing.

[0023] According to the above scheme, in step S2, the specific method of low temperature extrusion treatment is: firstly freeze the defatted rapeseed hull powder in a liquid nitrogen environment for 5-20 minutes, and then enter the twin-screw extruder for extrusion, with a screw speed of 50-200 r / min. Preferably, freeze for 10 minutes and the screw speed is 100 r / min.

[0024] According to the above scheme, in step S3, the specific method of low eutectic solvent treatment is as follows: the low eutectic solvent uses choline chloride / citric acid, or choline chloride / glycerol, or choline chloride / urea in a molar ratio of 1: (1-3), and the solid-liquid ratio is 1:20 (g / mL). The reaction is stirred at 100° C. for 20-60 min, and the low eutectic solvent is removed by filtration.

[0025] Preferably, the low eutectic solvent is choline chloride / citric acid in a mass ratio of 1:2, and the reaction is carried out for 45 minutes.

[0026] According to the above scheme, in step S4, the specific method of bleaching treatment is as follows: the rapeseed husk treated with a low eutectic solvent is placed in a 5.0% hydrogen peroxide solution with a solid-liquid ratio of 1:20 (g / mL), stirred at 80°C for 4 h, filtered and washed until the pH reaches neutral, and the filter residue is naturally dried to obtain rapeseed husk microcrystalline cellulose.

[0027] As a non-thermal food processing technology, pulsed electric field has received increasing attention in recent years. For oilseeds, pulsed electric field pretreatment technology involves the use of higher intensity electric fields, high frequency pulses and short pulse durations to treat oilseeds, with the aim of increasing the permeability of cell membranes and thus increasing the oil extraction rate. Studies have shown that after rapeseed was pretreated with pulsed electric fields, the iodine value and saponification value of its oil were not affected, while the content of bioactive components such as tocopherols, phytosterols and polyphenols increased.

[0028] Radio frequency heating technology heats materials by using electromagnetic waves with a frequency between 3kHz and 300MHz. When the material is in an electromagnetic field, the molecular movement converts electromagnetic energy into heat energy, thereby heating the material both inside and outside. This technology has the characteristics of fast heating speed, uniform heating, energy saving and low maintenance cost. It is widely used in pest control, sterilization, drying, thawing and cooking of food and agricultural products.

[0029] Magnetic field is a special material form that is ubiquitous in nature. It can be divided into static magnetic field, pulsed magnetic field, pulsating magnetic field and alternating magnetic field according to its intensity and direction. Low-intensity magnetic field has a promoting effect on organisms, while high-intensity magnetic field may have an inhibitory effect. Initially, magnetic field research focused on the use of high-intensity magnetic field for sterilization and its mechanism of action. With the deepening of research, the application of low-intensity magnetic field in the field of fermentation is increasing. Now, as a conventional non-thermal physical processing method, low-intensity magnetic field plays an important role in promoting microbial growth and metabolism.

[0030] Ultrasonic microwave synergistic extraction technology combines the cavitation effect of ultrasound and the high energy characteristics of microwaves. It realizes open extraction under normal pressure conditions by directly acting or focusing the ultrasonic vibration energy and microwave energy on the sample. This technology has been successfully applied to the extraction of bioactive ingredients such as carotenoids, polysaccharides, purple potato pigments and flavonoids, but is less used in plant oil extraction. Compared with the traditional Soxhlet extraction method, this technology is faster, more efficient, safer and more environmentally friendly; compared with the high-pressure closed microwave-assisted extraction method, it has a larger processing capacity, is less affected by the water content of the sample, and is safer and more reliable; compared with the ultrasonic-assisted extraction method, it has a higher extraction rate.

[0031] High-energy ray irradiation can destroy the structure of lignocellulose and cause the scission of polysaccharide chains. The weakly acidic groups generated by irradiation can further catalyze the chain scission and depolymerization of lignocellulose in aqueous solution, which makes this method effective in the pretreatment of lignocellulose component separation.

[0032] Dynamic ultra-high pressure microfluidic extraction technology is an emerging method for extracting natural ingredients. Its working principle is to use a high-pressure microfluidic homogenizer to release high pressure in an instant, generating strong shear force and high-speed collision effects, thereby promoting deep rupture and ultra-fine refinement of cell walls. This technology can significantly increase the mass transfer rate, which is conducive to the diffusion and extraction of natural ingredients inside cells. A low eutectic solvent is an ionic transparent liquid synthesized by a coordination reaction of two or more components, and its freezing point is much lower than the melting point of each component. According to the basic principles of green chemistry, low eutectic solvents meet the standards of environmental protection, non-toxicity, and renewability, and can be used as Lewis acid catalysts and reaction media. At present, low eutectic solvents are used as a new solvent to replace ionic liquids for pretreatment of fiber raw materials, which helps to reduce costs.

[0033] Compared with the prior art, the present invention has the following beneficial effects: (1) The present invention treats rapeseed with a pulsed electric field and radio frequency, uses ascorbyl palmitate-D-limonene / ethanol solution as an extraction medium, and adopts a low-intensity alternating magnetic field and ultrasonic-microwave combined extraction technology to prepare rapeseed oil. The obtained rapeseed oil has excellent quality, and the oil production process does not pollute the environment, and is clean and environmentally friendly.

[0034] (2) The present invention performs irradiation treatment on rapeseed meal and then washes it with alcohol to obtain crude rapeseed meal protein, and then uses high-pressure microfluidization and ultrafiltration technology to prepare refined rapeseed meal protein. The obtained rapeseed meal protein has excellent quality and the preparation process is environmentally friendly and energy-saving.

[0035] (3) The present invention adopts low-temperature extrusion-low eutectic solvent to prepare rapeseed husk microcrystalline cellulose, which saves costs to a great extent and is conducive to further promoting the transformation of rapeseed husk resources from waste to treasure.

[0036] (4) Microcrystalline cellulose has a wide range of applications in food, medicine and other fields. It can be used as a functional food base and dietary cellulose to develop healthy food, and can also be used as a drug excipient and tablet disintegrant. Rapeseed husk is rich in crude fiber. The present invention extracts microcrystalline cellulose from rapeseed husk through efficient separation technology, realizes the resource utilization of agricultural waste, reduces environmental pollution, and meets the requirements of sustainable development. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 : The process flow chart of rapeseed comprehensive utilization of the present invention. DETAILED DESCRIPTION

[0038] The following examples further illustrate the technical solution of the present invention, but are not intended to limit the scope of protection of the present invention.

[0039] The specific implementation method provides a method for comprehensive utilization of rapeseed, referring to the attached Figure 1 As shown: Moisture regulation treatment: moisture regulation treatment is carried out on rapeseed; Pretreatment: Rapeseed is treated with pulsed electric field-radio frequency combination; Peeling treatment: The rapeseed after radio frequency treatment is peeled to obtain rapeseed kernels and rapeseed husks respectively.

[0040] The obtained rapeseed kernels are further processed as follows: Crushing treatment: ultrafine grinding the peeled rapeseed kernels into raw materials for oil extraction; Soaking treatment: soaking rapeseed kernel powder in solvent; Oil extraction and separation: low-intensity alternating magnetic field-ultrasonic microwave synergistic extraction; Oil separation: Centrifuge the mixed liquid to separate rapeseed oil and rapeseed meal.

[0041] The obtained rapeseed meal is further processed as follows: Irradiation treatment: the rapeseed meal is placed in an irradiation device and irradiated at room temperature; Alcohol washing: adding isopropanol aqueous solution to the irradiated rapeseed meal powder for washing to separate and obtain crude rapeseed meal protein; High-pressure microfluidization treatment: add methanol aqueous solution to the crude rapeseed meal protein, pre-homogenize in a high-pressure homogenizer, and then put it into a high-pressure microfluidizer for dynamic ultra-high-pressure microfluidization treatment. After vacuum filtration, ultrafiltration purification, and freeze-drying, refined rapeseed meal protein is obtained.

[0042] The obtained rapeseed peel is further processed as follows: Degreasing: crushing and degreasing the rapeseed skin; Low temperature extrusion: Defatted rapeseed husks are treated with liquid nitrogen at low temperature and then subjected to twin-screw extrusion; Low eutectic solvent treatment: low temperature extruded rapeseed hull powder is treated with a low eutectic solvent; the synthesis method of the low eutectic solvent is: choline chloride and citric acid, or glycerol, or urea are mixed in a molar ratio of 1: (1-3), heated to 80°C, and stirred and mixed until it becomes a homogeneous transparent liquid; Bleaching treatment: After drying, bleaching treatment is carried out to obtain rapeseed hull microcrystalline cellulose.

[0043] Example 1 A certain amount of distilled water was added to the raw rapeseed, and the mixture was sealed and placed in a 4°C refrigerator overnight to make the moisture content in the rapeseed reach 10%. The rapeseed was treated with a pulsed electric field at a plate spacing of 45 mm, a pulse voltage of 15 kV, a material residence time of 60 s, a pulse frequency of 300 Hz, and a pulse width of 3 μs. The rapeseed was then subjected to radio frequency treatment at a frequency of 27.12 MH, an electrode gap of 70 mm, a cavity temperature of 80°C, and a radio frequency temperature of 100°C. The rapeseed pretreated with radio frequency was dehulled with a rapeseed dehulling machine, and then the rapeseed kernel and rapeseed skin were obtained respectively.

[0044] For rapeseed kernels, the rapeseed kernels were first crushed to an average volume particle size of 180-220 μm using a pulverizer, then crushed to an average volume particle size of 30-100 μm using a grinder, and finally crushed to an average volume particle size of 5-20 μm using an airflow superfine pulverizer. Then, the oil was soaked in a solvent of ascorbyl palmitate (concentration 0.5%)-D-limonene / ethanol solution (ratio 1:0.2), solid-liquid ratio 1:2, and soaking time 0.5 h. Subsequently, low-intensity alternating magnetic field and ultrasonic microwave synergistic treatment were performed, with a magnetic field intensity of 20 GS and a magnetic field treatment time of 1 h; ultrasonic power 50 W, microwave power 100 W, solid-liquid ratio 1:2, extraction temperature 50 ° C, and extraction time 5 min. The extract was collected and centrifuged at 8000 r / min for 20 min, and then the solvent was removed by rotary evaporation to collect the upper clear oil.

[0045] For rapeseed meal, rapeseed meal powder was first placed in a metal box of an irradiation device and irradiated at room temperature with a radiation source activity of 2.96×10 16Bq, irradiation dose 200kGy. Then add 70% (V / V) isopropanol aqueous solution to the irradiated rapeseed meal powder for washing, stirring speed 150r / min, solid-liquid ratio 1:4, temperature 30℃, time 20min, then centrifugal separation, solids freeze-dried to obtain crude rapeseed meal protein. Finally, high-pressure microfluidization fine powder was performed, 70% (V / V) methanol aqueous solution was added to the crude rapeseed meal protein, the solid-liquid ratio was 1:4, mixed evenly, pre-homogenized in a high-pressure homogenizer, time 30s, pressure 10Mpa, 1 time, then placed in a high-pressure microfluidizer for dynamic ultra-high pressure microfluidization treatment, time 5min, pressure 90Mpa, temperature 30℃, finally vacuum filtration, ultrafiltration purification (10kDa), freeze drying to obtain refined rapeseed meal protein.

[0046] For rapeseed skin, the rapeseed skin was first crushed with a grinder and then passed through an 80-mesh sieve. The rapeseed skin was then defatted by Soxhlet extraction, and the defatted rapeseed skin powder was obtained by drying after desolventizing. Then it was frozen in a liquid nitrogen environment for 5 minutes, entered into a twin-screw extruder for extrusion, and the screw speed was 50r / min. Then it was placed in a low eutectic solvent choline chloride-citric acid (1:1), with a solid-liquid ratio of 1:20 (g / mL), and stirred continuously with a magnetic stirrer in a constant temperature water bath at 100°C. After reacting for 20 minutes, it was filtered several times until the low eutectic solvent was removed. It was then placed in 5.0w / v% H2O2, with a solid-liquid ratio of 1:20 (g / mL), and stirred continuously with a magnetic stirrer in a constant temperature water bath at 80°C. After reacting for 4 hours, it was filtered several times until the pH of the filtrate reached neutrality, and the residue was naturally dried to obtain rapeseed skin microcrystalline cellulose.

[0047] Embodiment 2: A certain amount of distilled water was added to the raw rapeseed, and the mixture was sealed and placed in a 4°C refrigerator overnight to make the moisture content in the rapeseed reach 11%. The rapeseed was treated with a pulsed electric field at a plate spacing of 45 mm, a pulse voltage of 35 kV, a material residence time of 150 s, a pulse frequency of 800 Hz, and a pulse width of 8 μs. Then, the rapeseed was subjected to radio frequency treatment at a frequency of 27.12 MH, an electrode gap of 70 mm, a cavity temperature of 80°C, and a radio frequency temperature of 140°C. The rapeseed pretreated with radio frequency was peeled with a rapeseed peeling machine, and then the rapeseed kernel and rapeseed skin were obtained respectively.

[0048] For rapeseed kernels, the rapeseed kernels were first crushed with a crusher to a volume average particle size of 180-220 μm, then crushed with a grinder to a volume average particle size of 30-100 μm, and finally crushed with an airflow superfine grinder to an oil extraction raw material with a volume average particle size of 5-20 μm. Then, the soaking treatment was carried out, and the solvent was ascorbyl palmitate (concentration 0.5%)-D-limonene / ethanol solution (ratio 1:1), solid-liquid ratio 1:5, and soaking time 2.0 h. Subsequently, low-intensity alternating magnetic field and ultrasonic microwave synergistic treatment were carried out, with a magnetic field intensity of 80 GS and a magnetic field treatment time of 3 h; ultrasonic power 70 W, microwave power 300 W, solid-liquid ratio 1:5, extraction temperature 50 ° C, and extraction time 20 min. The extract was collected, centrifuged at 8000 r / min for 20 min, and then the solvent was removed by rotary evaporation to collect the upper clear oil.

[0049] For rapeseed meal, rapeseed meal powder was first placed in a metal box of an irradiation device and irradiated at room temperature with a radiation source activity of 2.96×10 16 Bq, irradiation dose 400kGy. Then add 70% (V / V) isopropanol aqueous solution to the irradiated rapeseed meal powder for washing, stirring speed 150r / min, solid-liquid ratio 1:6, temperature 50℃, time 50min, then centrifugal separation, solids freeze-dried to obtain crude rapeseed meal protein. Finally, high-pressure microfluidization fine powder was performed, 70% (V / V) methanol aqueous solution was added to the crude rapeseed meal protein, the solid-liquid ratio was 1:6, mixed evenly, pre-homogenized in a high-pressure homogenizer, time 30s, pressure 20Mpa, 2 times, then placed in a high-pressure microfluidizer for dynamic ultra-high pressure microfluidization treatment, time 5min, pressure 110Mpa, temperature 40℃, finally vacuum filtration, ultrafiltration purification (10kDa), freeze drying to obtain refined rapeseed meal protein.

[0050] For rapeseed skin, the rapeseed skin was first crushed with a grinder and passed through an 80-mesh sieve. The rapeseed skin was then defatted by Soxhlet extraction, and the defatted rapeseed skin powder was obtained by drying after desolventizing. Then it was frozen in a liquid nitrogen environment for 15 minutes, entered a twin-screw extruder for extrusion, and the screw speed was 150r / min. Then it was placed in a low eutectic solvent choline chloride-citric acid (1:2), with a solid-liquid ratio of 1:20 (g / mL), and stirred continuously with a magnetic stirrer in a constant temperature water bath at 100°C. After reacting for 35 minutes, it was filtered several times until the low eutectic solvent was removed. It was then placed in 5.0w / v% H2O2, with a solid-liquid ratio of 1:20 (g / mL), and stirred continuously with a magnetic stirrer in a constant temperature water bath at 80°C. After reacting for 4 hours, it was filtered several times until the pH of the filtrate reached neutrality, and the residue was naturally dried to obtain rapeseed skin microcrystalline cellulose.

[0051] Embodiment 3: A certain amount of distilled water was added to the raw rapeseed, and the mixture was sealed and placed in a 4°C refrigerator overnight to make the moisture content in the rapeseed reach 12%. The rapeseed was treated with a pulsed electric field at a plate spacing of 45 mm, a pulse voltage of 45 kV, a material residence time of 210 s, a pulse frequency of 1000 Hz, and a pulse width of 10 μs. The rapeseed was then subjected to radio frequency treatment at a frequency of 27.12 MH, an electrode gap of 70 mm, a cavity temperature of 80°C, and a radio frequency temperature of 160°C. The rapeseed pretreated with radio frequency was dehulled with a rapeseed dehulling machine, and then the rapeseed kernel and rapeseed skin were obtained respectively.

[0052] For rapeseed kernels, the rapeseed kernels were first crushed with a crusher to a volume average particle size of 180-220 μm, then crushed with a grinder to a volume average particle size of 30-100 μm, and finally crushed with an airflow superfine grinder to an oil extraction raw material with a volume average particle size of 5-20 μm. Then, the soaking treatment was carried out, and the solvent was ascorbyl palmitate (concentration 0.5%)-D-limonene / ethanol solution (ratio 1:2), solid-liquid ratio 1:8, and soaking time 3.0 h. Subsequently, low-intensity alternating magnetic field and ultrasonic microwave synergistic treatment were carried out, with a magnetic field intensity of 180 GS and a magnetic field treatment time of 8 h; ultrasonic power 100 W, microwave power 500 W, solid-liquid ratio 1:8, extraction temperature 70 ° C, and extraction time 30 min. The extract was collected, centrifuged at 8000 r / min for 20 min, and then the solvent was removed by rotary evaporation to collect the upper clear oil.

[0053] For rapeseed meal, rapeseed meal powder was first placed in a metal box of an irradiation device and irradiated at room temperature with a radiation source activity of 2.96×10 16 Bq, irradiation dose 800kGy. Then add 70% (V / V) isopropanol aqueous solution to the irradiated rapeseed meal powder for washing, stirring speed 150r / min, solid-liquid ratio 1:8, temperature 60℃, time 80min, then centrifugal separation, solids freeze-dried to obtain crude rapeseed meal protein. Finally, high-pressure microfluidization fine powder was performed, 70% (V / V) methanol aqueous solution was added to the crude rapeseed meal protein, the solid-liquid ratio was 1:10, mixed evenly, pre-homogenized in a high-pressure homogenizer, time 30s, pressure 30Mpa, 3 times, then placed in a high-pressure microfluidizer for dynamic ultra-high pressure microfluidization treatment, time 5min, pressure 130Mpa, temperature 60℃, finally vacuum filtration, ultrafiltration purification (10kDa), freeze drying to obtain refined rapeseed meal protein.

[0054] For rapeseed skin, the rapeseed skin was first crushed with a grinder and then passed through an 80-mesh sieve. The rapeseed skin was then defatted by Soxhlet extraction, and the defatted rapeseed skin powder was obtained by drying after desolventizing. Then it was frozen in a liquid nitrogen environment for 20 minutes, entered a twin-screw extruder for extrusion, and the screw speed was 200r / min. It was then placed in a low eutectic solvent choline chloride-citric acid (1:3), with a solid-liquid ratio of 1:20 (g / mL), and stirred continuously with a magnetic stirrer in a constant temperature water bath at 100°C. After reacting for 60 minutes, it was filtered several times until the low eutectic solvent was removed. It was then placed in 5.0w / v% H2O2, with a solid-liquid ratio of 1:20 (g / mL), and stirred continuously with a magnetic stirrer in a constant temperature water bath at 80°C. After reacting for 4 hours, it was filtered several times until the pH of the filtrate reached neutrality, and the residue was naturally dried to obtain rapeseed skin microcrystalline cellulose.

[0055] The quality indexes of rapeseed oil obtained in Examples 1, 2 and 3 are shown in Table 1. The quality indexes of rapeseed meal protein obtained in Examples 1, 2 and 3 are shown in Table 2. The quality indexes of rapeseed hull microcrystalline cellulose obtained in Examples 1, 2 and 3 are shown in Table 3.

[0056] Table 1

[0057] Table 2

[0058] Table 3

[0059] Finally, it should be noted that the above are only preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments or to replace some of the technical features therein with equivalents. However, any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for comprehensive utilization of rapeseed, characterized in that The following steps are involved: (1) Water regulation: adjust the moisture of rapeseed; (2) Pretreatment: Rapeseed is treated with pulsed electric field-radio frequency combination; (3) Peeling: Peeling the pretreated rapeseed to obtain rapeseed kernels and rapeseed husks; (4) Crushing: ultrafinely crushing the rapeseed kernels into rapeseed kernel powder, which is the raw material for oil extraction; (5) Soaking treatment: soaking the rapeseed kernel powder in a solvent; (6) Oil extraction and separation: low-intensity alternating magnetic field-ultrasonic microwave synergistic extraction; (7) Oil separation: centrifuging the extracted mixed liquid to separate rapeseed oil and rapeseed meal; (8) Irradiation treatment: placing the rapeseed meal in an irradiation device and irradiating it at room temperature; (9) Alcohol washing: adding an isopropanol aqueous solution to the irradiated rapeseed meal for washing to separate and obtain crude rapeseed meal protein; (10) High-pressure microfluidization treatment: A methanol-water solution is added to the crude rapeseed meal protein, which is pre-homogenized in a high-pressure homogenizer and then placed in a high-pressure microfluidizer for dynamic ultrahigh-pressure microfluidization treatment. Refined rapeseed meal protein is obtained after vacuum filtration, ultrafiltration purification, and freeze-drying.

2. The method for comprehensive utilization of rapeseed as claimed in claim 1, characterized in that In step (1), the specific method for adjusting the moisture content is as follows: distilled water is added to the raw rapeseed, and the raw rapeseed is sealed and allowed to stand at 4° C. for more than 12 hours, so that the moisture content in the rapeseed reaches 10-12wt%.

3. The method for comprehensive utilization of rapeseed as claimed in claim 1, characterized in that In step (2), the parameters of the pulse electric field treatment are: plate spacing of 45 mm, pulse voltage of 15-45 kV, material residence time of 60-210 s, pulse frequency of 300-1000 Hz, and pulse width of 3-10 μs.

4. The method for comprehensive utilization of rapeseed as claimed in claim 1, characterized in that In step (5), the solvent for the soaking treatment is a D-limonene / ethanol solution of ascorbyl palmitate, wherein the concentration of ascorbyl palmitate is 0.1-1.0wt%, and the volume ratio of D-limonene to ethanol is 1:(0.2-2); the solid-liquid ratio of the soaking treatment is 1:(2-8) g / mL, and the soaking treatment time is 0.5-3.0h.

5. The method for comprehensive utilization of rapeseed as claimed in claim 1, characterized in that In step (6), the parameters of the low-intensity alternating magnetic field are: magnetic field intensity 20-180 GS, magnetic field treatment time 1-8h; the parameters of the ultrasonic microwave synergistic treatment are: ultrasonic power 50-100W, microwave power 100-500W, extraction temperature 50-70°C, and extraction time 5-30min.

6. The method for comprehensive utilization of rapeseed as claimed in claim 1, characterized in that In step (8), the specific method of irradiation treatment is as follows: the rapeseed meal is placed in a metal box of an irradiation device and irradiated at room temperature. The activity of the radiation source is fixed at 2.96×10 16 Bq, set the irradiation dose parameter to: 200-800 kGy.

7. The method for comprehensive utilization of rapeseed as claimed in claim 1, characterized in that In step (10), the specific method of high-pressure microfluidization is as follows: 70vt% methanol aqueous solution is added to the crude rapeseed meal protein, the solid-liquid ratio is 1:4-10, the mixture is evenly mixed, and the mixture is pre-homogenized in a high-pressure homogenizer for a fixed time of 30s, a pressure of 10-30Mpa, and a number of times of 1-3 times, and then the mixture is placed in a high-pressure microfluidizer for dynamic ultra-high pressure microfluidization treatment for a fixed time of 5min, a pressure of 90-130Mpa, and a temperature of 30-60°C, and finally the refined rapeseed meal protein is obtained after vacuum filtration and freeze drying.

8. The method for comprehensive utilization of rapeseed as claimed in claim 1, characterized in that Step 3 also includes utilizing the rapeseed peel, including the following steps: S1, defatting: crushing and defatting the rapeseed husk to obtain defatted rapeseed husk powder; S2, low temperature extrusion: the defatted rapeseed hull powder is treated with liquid nitrogen at low temperature and then subjected to twin-screw extrusion; S3, low eutectic solvent treatment: low eutectic solvent treatment is performed on the defatted rapeseed husk powder after low temperature extrusion; S4. Bleaching treatment: After drying, bleaching treatment is performed to obtain rapeseed hull microcrystalline cellulose.

9. The method for comprehensive utilization of rapeseed as claimed in claim 8, characterized in that The specific method of the defatting treatment in step S1 is as follows: firstly, the rapeseed husk is crushed by a pulverizer and then passed through an 80-mesh sieve, then the rapeseed husk is defatted by a Soxhlet extraction method, and then the defatted rapeseed husk powder is obtained by drying after desolventizing; the specific method of the low-temperature extrusion treatment in step S2 is as follows: firstly, the defatted rapeseed husk powder is frozen in a liquid nitrogen environment for 5-20 minutes, and then enters a twin-screw extruder for extrusion, and the screw speed is 50-200r / min.

10. The method for comprehensive utilization of rapeseed according to claim 8, characterized in that The specific method of low eutectic solvent treatment in step S3 is as follows: the low eutectic solvent adopts choline chloride / citric acid, or choline chloride / glycerol, or choline chloride / urea in a molar ratio of 1: (1-3), the solid-liquid ratio is 1:20 g / mL, the reaction is stirred at 100° C. for 20-60 min, and the low eutectic solvent is removed by filtration; the specific method of bleaching treatment in step S4 is as follows: the rapeseed husk treated with the low eutectic solvent is placed in a 5.0% hydrogen peroxide solution, the solid-liquid ratio is 1:20 g / mL, the reaction is stirred at 80° C. for 4 h, the filtration and washing are performed until the pH reaches neutral, and the filter residue is naturally dried to obtain the rapeseed husk microcrystalline cellulose.

Images