CN104194920B - A kind of preparation method of fructus cannabis oil - Google Patents

Abstract

The invention discloses the preparation method of a kind of fructus cannabis oil, the method include fire fiber crops seed cleaning removal of impurities, high frequency vacuum drying, laser shell in advance, extrude that shelling, malleation be quenched, cold pressing, high-voltage pulse subcritical abstraction fructus cannabis cake, the step such as low temperature crystallization degumming and dewaxing, moving-bed type adsorption deacidification and filtration, the method has produces that efficiency is high, refining energy consumption is low, refining low, the advantages of environment protection of consumption.

Description

A kind of preparation method of hemp seed oil

technical field

The invention belongs to the technical field of oil processing, and in particular relates to a preparation method of hemp seed oil.

technical background

Hemp is a herbaceous plant with short sunshine, annual, palmately divided leaves and mostly dioecious plants, which has the characteristics of barren tolerance and stress resistance. At present, many countries in the world plant industrial hemp, and my country's hemp production accounts for about 1/3 of the world's hemp production, ranking first in the world. The oil content of ordinary hemp seeds is 30% to 40%, and the ratio of linoleic acid to linolenic acid is close to 2.5, which is the best ratio of fatty acids required by the human body. Hemp seed oil is rich in trace mineral elements, such as phosphorus, iron, potassium, magnesium, zinc and so on. Hemp seed oil has been applied to various foods, including hemp chocolate, hemp cake, hemp candy, hemp bread and tea drinks and other health food series. At the same time, hemp seed oil is a high-quality substance with the same source of medicine and food. It contains extremely rich phytosterols. Through dietary intake, it can significantly reduce serum cholesterol and has good antibacterial and anti-inflammatory effects; hemp seed oil The highest content is γ-tocopherol, which has obvious effects on coronary heart disease, tumor prevention and reduction of DNA damage; some researchers have also found that hemp seed oil is suitable as an antioxidant dietary resource, and it can eliminate DPPH free radicals In addition, hemp seed oil contains more than 60 kinds of phenolic chemicals, which have good antioxidant properties and have a strong ability to scavenge free radicals under lower dosage conditions.

The traditional edible oil preparation technology mainly adopts pre-pressing and solvent leaching, and then refines crude oil through chemical degumming, chemical deacidification, high-temperature decolorization and high-temperature deodorization. The products are mainly primary and secondary oils. The disadvantages are that the use of chemical reagents and excessive refining lead to serious loss and damage of natural active substances such as vitamin E, phytosterols, and carotenoids in the oil. Hazardous substances such as aromatic hydrocarbons. At present, in response to the above problems, some researchers have conducted research on the preparation technology of hemp seed oil.

CN 1563306A discloses a preparation method and application of hemp seed oil. The cold-pressed hemp seed oil is obtained by husking and cold pressing, and then filtered and centrifuged. At the same time, the cold-pressed cake is extracted with propane or butane to obtain The extracted oil is refined and anti-oxidized to obtain refined hemp seed oil, which is finally made into soft capsules. This technology can produce most of the hemp seed oil, but it does not involve the low-temperature refining technology of hemp seed oil.

CN 101177647A discloses a process for processing hemp oil, which uses airflow drying, shelling, drying, tempering, normal temperature pressing, centrifugation, and filtration to obtain cold-pressed refined hemp oil. This technology is practical and reliable, but The low-temperature refining technology of hemp seed oil is not involved.

CN 102585999A discloses a method for extracting hemp seed oil, which is prepared by washing with water, microwave heating, pressing, filtering and disinfection. This technology does not involve the technology of shelling hemp seeds and the low-temperature refining technology of hemp seed oil .

CN 102816631A discloses a method for extracting hemp seed oil by acid extrusion and enzymatic method. Sulfuric acid is used to pretreat the hemp seeds, then extruded and expanded, and then the oil is produced by aqueous enzymatic method. This technology can obtain better quality Hemp seed oil and hemp protein, but not related to the technology of shelling hemp seeds and the low-temperature refining technology of hemp seed oil.

CN 103289819A discloses a process for extracting hemp seed oil with supercritical carbon dioxide. This technology has the advantages of no pollution, no solvent residue, low extraction temperature, and safe use, but it does not involve the shelling technology of hemp seeds and the technology of hemp seeds. Low temperature refining technology of kernel oil.

From the point of view of the above-mentioned hemp seed oil preparation methods, the main attention is still on the extraction method of hemp seed oil, and the research on the pretreatment and shelling technology of hemp seeds and the low-temperature refining technology of hemp seed oil is relatively lacking.

Contents of the invention

The purpose of the present invention is to provide a preparation method of hemp seed oil. The preparation method pre-hulls the hemp seeds and adopts low-temperature refining technology, which has the advantages of high drying efficiency, low refining energy consumption, low refining consumption, Environmentally friendly and other advantages.

The above-mentioned purpose of the present invention is achieved by the following technical scheme: a kind of preparation method of hemp seed oil, this method comprises the following steps:

(1) cleaning, drying: select fresh hemp seeds, and adopt high-frequency vacuum drying after cleaning;

(2) Pre-hulling: cutting the hemp seeds after step (1) high-frequency vacuum drying with a laser to obtain pre-hulling hemp seeds;

(3) Shelling: Extruding and shelling the hemp seeds processed in step (2) pre-hulling to obtain the hemp seeds and the shell;

(4) Positive pressure conditioning: adopt the positive pressure conditioning mode to regulate the moisture of the hemp seed obtained in the step (3);

(5) Low-temperature pressing: adopt mechanical pressing equipment to carry out low-temperature pressing to the hemp seed obtained in step (4), obtain the hemp seed crude oil 1 and press the hemp seed cake;

(6) High-pressure pulse subcritical extraction: the hemp seed cake obtained in step (5) is processed by using a high-pressure pulse subcritical extraction method to obtain hemp seed crude oil 2 and hemp seed meal;

(7) Low-temperature crystallization degumming and dewaxing: add filter aid in the hemp seed hair oil 1 obtained in step (5) and the hemp seed hair oil 2 obtained in step (6) and stir, then uniformly cool down, and then carry out Cold analysis treatment, filtered to obtain degummed and dewaxed hemp seed oil;

(8) moving bed type adsorption deacidification, filtration: add deacidification adsorbent in the moving bed reactor to carry out deacidification treatment to the degummed and dewaxed hemp seed oil obtained in step (7), to obtain deacidified hemp seed oil, Sealed and preserved after filtering, the hemp seed oil can be obtained.

The preparation method of the hemp seed oil in the present invention includes high-frequency vacuum drying, laser pre-shelling, positive pressure conditioning, low-temperature pressing, high-pressure pulse subcritical extraction, low-temperature crystallization degumming and dewaxing, and moving bed adsorption. Acid and other technical means.

In the preparation method of this hemp seed oil:

The cleaning in the step (1) mainly refers to selecting fresh hemp seeds, cleaning and separating to remove impurities such as weeds, marl, stones, metals.

The parameters of high-frequency vacuum drying in step (1) are: frequency 6MHz～28MHz, voltage intensity 1000V/cm～3000V/cm, vacuum degree 300Pa～3000Pa, adopt high-frequency vacuum drying to the mass percentage of water in hemp seeds The content is 7-11%.

The various parameters when adopting laser to cut in the step (2) are: power 6W～50W, laser cutting rate 5mm/s～35mm/s, adopt laser to cut, the width of cutting to the slit of hemp seed is 0.5mm ~3.5mm.

In step (3), when the hemp seeds of step (2) pre-hulling process are extruded and shelled, the extrusion equipment used is a toothed roller extrusion sheller, and the shelling of the hemp seeds is The rate is 85% to 98%.

The positive pressure tempering method described in step (4) is: input the hemp seed into the stirring equipment, evenly feed water, continue to stir for 10min to 30min, and the stirring rate is 60 to 180 rpm; In the pressure-resistant container, set the pressure at 0.2MPa-3MPa, and treat for 15min-60min; the moisture content of the hemp seed after conditioning is 7%-13%.

In the step (5), the temperature of the hemp seeds obtained in the step (4) is 25° C. to 70° C. when the mechanical pressing equipment is used for low-temperature pressing.

When the high-voltage pulse subcritical extraction method is used in step (6) to process the hemp seed cake obtained in step (5), the parameters are: pulse voltage 5kv～35kv, pulse time 10μs～100μs, solvent used during subcritical extraction It is butane, the subcritical extraction pressure is 0.3MPa~1.5MPa, the extraction time is 0.8h~4.0h, and the extraction temperature is 8°C~50°C.

The specific process of carrying out low-temperature crystallization degumming and dewaxing treatment in step (7) is: adding filter aid in the hemp seed crude oil 1 obtained in step (5) and the hemp seed crude oil 2 obtained in step (6) Stir for 15min~30min, the stirring rate is 20rpm~80rpm, then uniformly cool down to 0℃~16℃, when the temperature is uniformly lowered, the stirring rate is 5rpm~35rpm, and the cooling time is 2h~6h ,, after the temperature is stable, keep it for 4h-12h for cold analysis, and finally add diatomaceous earth and use a pressure leaf filter to filter to obtain degummed and dewaxed hemp seed oil, wherein the filter aid is hemp seed cake powder, The amount of the hemp seed cake powder accounts for 0.05%-0.3% of the total mass of the hemp seed crude oil 1 and the hemp seed crude oil 2.

The filter aid hemp seed cake powder that adopts in the step (7), can adopt the hemp seed cake that obtains in the above-mentioned step (5) of the present invention and the hemp seed meal that obtains in the step (6) to obtain after pulverizing, pulverize The hemp seed cake powder that obtains after the mesh number is 60 order～120 orders, also can adopt commercially available hemp seed cake or hemp seed cake pulverization to obtain, but the consumption of filter aid is not big among the present invention, this The hemp seed cake and the hemp seed cake obtained in the process of preparing the hemp seed oil can be used sufficiently.

In step (8), when adding a deacidifying adsorbent to the moving bed reactor to deacidify the degummed and dewaxed hemp seed oil obtained in step (7), the degummed and dewaxed hemp seed oil circulates in and out from bottom to top, The deacidification adsorbent is from top to bottom, wherein the deacidification temperature is 20°C to 70°C, and the adsorption time is 0.5h to 3.5h.

The deacidification adsorbent of the present invention is made by mixing three kinds of raw materials of alkaline bentonite, silicon dioxide and diatomite, and the mass percentage of each raw material is: alkaline bentonite 45%～85%, silicon dioxide 10% %～50% and diatomaceous earth 5%～20%.

The alkaline bentonite is prepared by grinding bentonite and sodium hydroxide at normal temperature, and the amount of sodium hydroxide accounts for 15-25% of the total mass of the bentonite.

The preparation process of the deacidification adsorbent is as follows: the alkaline bentonite, silicon dioxide and diatomite are ground at normal temperature to prepare the deacidification adsorbent.

Compared with prior art, the present invention has following advantage:

(1) The inventive method adopts a high-frequency vacuum drier to adjust the moisture of hemp seeds quickly and without damage, and is suitable for industrialized production;

(2) the inventive method adopts the laser pre-hulling technology to cooperate with the toothed roller type extruding sheller to help improve the shelling rate of hemp seeds;

(3) The inventive method adopts positive pressure tempered hemp seed, has advantages such as simple and easy to operate, low energy consumption, high efficiency;

(4) The inventive method adopts the high-voltage pulse subcritical extraction of the hemp seed cake, which has the advantages of simple and easy operation, high extraction efficiency, and environmental friendliness;

(5) The method of the present invention adopts low-temperature crystallization degumming and dewaxing, and simultaneously removes colloid and wax, and has the advantages of simple operation and low energy consumption;

(6) The inventive method adopts moving bed type adsorption deacidification, which has the characteristics of high deacidification efficiency;

(7) In the method of the present invention, the overall process combines high-frequency vacuum dryer drying, laser pre-shelling, toothed roller extrusion shelling, positive pressure conditioning, low-temperature pressing, high-pressure pulse subcritical extraction, low-temperature crystallization degumming and degumming Wax, moving bed adsorption deacidification and other technologies have the advantages of low energy consumption, low refining consumption, high product quality, and environmental friendliness.

Description of drawings

Fig. 1 is the technological process schematic diagram that hemp seed oil is prepared in the embodiment of the present invention 1-6;

Fig. 2 is the oxidation induction period curve of hemp seed oil in Example 6 of the present invention.

detailed description

Example 1

As shown in Figure 1, fresh hemp seeds are selected, cleaned and separated to remove impurities, and then the hemp seeds are transported to high-frequency vacuum drying equipment for drying. The frequency is 27.12MHz, the voltage intensity is 1500V/cm, the vacuum degree is 1000Pa, Dried until the mass percentage of water in the hemp seeds is 8.5%, pre-shelling the dried hemp seeds, laser power 10W, laser cutting speed 10mm/s; cutting to the width of the laser slit of the hemp seeds It is 1.5mm, and then sent to the toothed roller extrusion shelling machine, wherein the shelling rate of hemp seeds is 91.5%; then, the hemp seeds are input into the mixing equipment, and water is introduced, and the stirring is continued for 15 minutes, and the stirring rate is 90 rpm. min; then transfer to the pressure-resistant container, set the pressure as 0.6MPa, and process for 30min, the water content of the hemp seeds after conditioning is 9%; The temperature of the hemp seeds is 50°C, and the hemp seed pressed crude oil 1 and the hemp seed cake are obtained by pressing; the hemp seed cake is put into the high-voltage pulse subcritical equipment, and the specific process of the high-voltage pulse subcritical in this embodiment can be referred to The operation process of high-voltage pulse supercritical, only the pressure adjustment and the extraction solvent are different, the same below, wherein the pulse voltage is 15kv, the pulse time is 55μs, the subcritical butane extraction pressure is 0.5MPa, the extraction time is 2.6h, the extraction temperature is 25°C, the extraction After completion, decompression obtains extraction hemp seed hair oil 2; Then, in hemp seed hair oil 1 and hemp seed hair oil 2, add 0.08% (the consumption of hemp seed cake powder accounts for the hemp seed hair oil gross mass 0.08%, the same below) filter aid hemp seed cake powder (the hemp seed cake powder is obtained by pulverizing the above-mentioned prepared or commercially available hemp seed cake or hemp seed meal, and the obtained after pulverization The hemp seed cake powder has a mesh number of 60 mesh to 120 mesh, the same below), continuously stirred for 20 minutes, and the stirring rate was 30 revolutions/min, then cooled to 5°C, the stirring speed was 15 revolutions/min, and the cooling time was 4 hours. Keep the temperature stable for 6h to carry out cold analysis treatment, then add diatomaceous earth and adopt a pressure type leaf filter (equipment model NYB-15, only for enumeration, not limited) to filter to obtain degummed and dewaxed hemp seed oil; The degummed and dewaxed hemp seed oil is circulated in and out from bottom to top, and the deacidification adsorbent is from top to bottom, wherein the deacidification temperature is controlled at 45°C, and the adsorption time is 1.5h; finally, the deacidified hemp seed oil is filtered, and Keep airtight.

The preparation method of the deacidification adsorbent in this example is: 1. alkaline bentonite, 2. silicon dioxide, 3. prepared by grinding three raw materials of diatomite, wherein the mass percentage of each raw material is: alkaline bentonite: 75%; Silicon dioxide: 15%; diatomite: 10%. Alkaline bentonite is made by grinding bentonite and sodium hydroxide at normal temperature, and the amount of sodium hydroxide accounts for 15% of the total mass of bentonite.

Example 2

As shown in Figure 1, fresh hemp seeds are selected, cleaned and separated to remove impurities, and then the hemp seeds are transported to high-frequency vacuum drying equipment for drying, wherein the frequency is 27.12MHz, the voltage intensity is 1000V/cm, and the vacuum degree is 500Pa. Vacuum dry to the mass percentage of water in the hemp seeds is 9.0%, pre-shell the dried hemp seeds, laser power 15W, laser cutting speed 15mm/s, cut to the laser slit of the hemp seeds The width of the hemp seed is 1.8mm, and then transported to the toothed roller extrusion shelling machine, wherein the peeling rate is 92%; then, the hemp seed is input into the mixing device, and water is passed into it, and the stirring is continued for 18 minutes, and the stirring rate is 70 rpm; then Then transfer to the pressure-resistant container, set the pressure at 0.9MPa, process for 25min, and the moisture content of the hemp seeds after conditioning is 8.5%; Hemp seed pressed crude oil 1 and hemp seed cake are obtained by pressing at 45°C; put the hemp seed cake into a high-voltage pulse subcritical equipment, where the pulse voltage is 20kv, the pulse time is 35μs, and the subcritical butane extraction pressure is 0.6 MPa, the extraction time is 3.0h, and the extraction temperature is 20°C. After the extraction is completed, the extracted hemp seed hair oil 2 is obtained under reduced pressure; Filter hemp seed cake powder, keep stirring for 15min, the stirring rate is 40 rpm, then cool down to 6°C, the stirring rate is 18 rpm, the cooling time is 3.5h, the temperature is stable and then maintain for 5.5h for cold analysis Then add diatomaceous earth and filter with a pressure leaf filter to obtain degummed and dewaxed hemp seed oil; then circulate the degummed and dewaxed hemp seed oil from bottom to top, and deacidification adsorbent from top to bottom , wherein the deacidification temperature is controlled at 40°C, and the adsorption time is 1.2h; finally, the deacidification hemp seed oil is filtered and sealed for storage.

The preparation method of deacidification sorbent in this example is: 1. alkaline bentonite, 2. silicon dioxide, 3. diatomite three kinds of raw materials are ground and prepared, and the mass percentage that each raw material accounts for is: basic bentonite: 60%; Silicon oxide: 35%; diatomite: 5%. Alkaline bentonite is made by grinding bentonite and sodium hydroxide at normal temperature, and the amount of sodium hydroxide accounts for 20% of the total mass of bentonite.

Example 3

As shown in Figure 1, fresh hemp seeds are selected, cleaned and separated to remove impurities, and then the hemp seeds are transported to high-frequency vacuum drying equipment for drying, wherein the frequency is 27.12MHz, the voltage intensity is 1600V/cm, and the vacuum degree is 800Pa. Vacuum-dried to the mass percentage of water in the hemp seeds is 8.0%, pre-shelling the dried hemp seeds, laser power 25W, laser cutting speed 25mm/s, cutting to the laser slit of the hemp seeds The width of the hemp seed is 2.0mm, and then transported to the toothed roller extrusion shelling machine, wherein the peeling rate is 95%; then, the hemp seed is input into the mixing device, and water is passed into it, and the stirring is continued for 20 minutes, and the stirring rate is 60 rpm; then Go in the pressure-resistant container again, setting pressure is 0.9MPa, handles 16min, the water content of the hemp seed after conditioning is 9.5%; Press at 35°C to obtain pressed crude oil 1 and hemp seed cake; put the hemp seed cake into a high-voltage pulse subcritical equipment, where the pulse voltage is 30kv, the pulse time is 30μs, and the subcritical butane extraction pressure is 0.4MPa , the extraction time is 3.3h, and the extraction temperature is 20°C. After the extraction is completed, extract hemp seed hair oil 2 under reduced pressure; then, add 0.12% filter aid to hemp seed hair oil 1 and hemp seed hair oil 2 Hemp seed cake powder, continue to stir for 20min, the stirring rate is 35 rpm, then cool down to 10°C, the stirring rate is 20 rpm, the cooling time is 3h, the temperature is stable and then maintain for 7h for cold analysis, and then Add diatomaceous earth and use a pressure leaf filter to filter to obtain degummed and dewaxed hemp seed oil; then the degummed and dewaxed hemp seed oil is circulated in and out from bottom to top, and the deacidification adsorbent is from top to bottom. The acid temperature is controlled at 40°C, and the adsorption time is 1.8h; finally, the deacidified hemp seed oil is filtered and sealed for storage.

The preparation method of deacidification sorbent in this example is: 1. alkaline bentonite, 2. silicon dioxide, 3. diatomite three kinds of raw materials are ground and prepared, and the mass percentage that each raw material accounts for is: alkaline bentonite: 80%; Silicon oxide: 10%; diatomite: 10%. Alkaline bentonite is made by grinding bentonite and sodium hydroxide at normal temperature, and the amount of sodium hydroxide accounts for 20% of the total mass of bentonite.

Example 4

The preparation method that present embodiment provides to produce hemp seed oil, as shown in Figure 1, the method comprises:

(1) Cleaning: select fresh hemp seeds, clean and separate to remove impurities such as weeds, marl, stones, metals, etc.;

(2) High-frequency vacuum drying: adopt high-frequency vacuum drying equipment to adjust the hemp seed moisture after cleaning in step (1), and the high-frequency vacuum drying parameters are: frequency is 6.78MHz, voltage intensity is 3000V/cm, vacuum degree 300Pa , the drying time is 30min, and the moisture content in the dried hemp seeds is 10.5%;

(3) Pre-hulling: adopt laser moderate cutting to process the dried hemp seeds in step (2), the laser processing parameters are: power 6W, laser cutting speed 35mm/s, the laser slit width cut to the hemp seeds is 0.6mm;

(4) Shelling: Extrude and shell the hemp seeds after the pre-shelling in step (3) to obtain the hemp seeds and shells. The extrusion equipment is a toothed roller extrusion shelling machine, and the hemp seeds are shelled The rate is 85%;

(5) Positive pressure conditioning: adjust the moisture content of the hemp seeds obtained in step (4) under positive pressure conditions. The positive pressure conditioning process is: input the hemp seeds into the mixing device, evenly feed water, continue stirring for 10min, and the stirring rate Be 180 revs/min, then change over to in the pressure-resistant container, set pressure as 0.2MPa, handle 60min, the hemp seed water content after tempering is 7%;

(6) Low-temperature pressing: adopt mechanical press to carry out low-temperature pressing to the hemp seed in step (5), obtain hemp seed crude oil 1 and press hemp seed cake, the temperature when low-temperature pressing hemp seed is 25 ℃;

(7) High-pressure pulse subcritical extraction: adopt the high-pressure pulse subcritical extraction method to process the hemp seed cake in step (6), and obtain the hemp seed crude oil 2 and the hemp seed meal. The specific process of the high-pressure pulse subcritical extraction is: The pulse voltage is 5kv, the pulse time is 100μs, the extraction solvent is butane, the subcritical butane extraction pressure is 0.3MPa, the extraction time is 4.0h, and the extraction temperature is 8°C;

(8) Low-temperature crystallization degumming and dewaxing: adding 0.05% filter aid hemp seed cake powder to the hemp seed hair oil 1 obtained in step (6) and/or the hemp seed hair oil 2 obtained in step (7) Stir, keep stirring for 15min, the stirring rate is 80 rpm; then cool down to 0°C, the stirring rate is 35 rpm, the cooling time is 2h, the temperature is stable and then maintain for 12h, then add diatomaceous earth and use pressure type Leaf filter for filtration;

(9) Moving bed type adsorption deacidification: add deacidification adsorbent in the moving bed reactor to carry out deacidification treatment to the degummed and dewaxed hemp seed oil obtained in step (8), to obtain deacidified hemp seed oil, wherein The acid adsorbent is prepared by mixing three raw materials: alkaline bentonite, silicon dioxide and diatomite, and the mass percentage of each raw material is: alkaline bentonite 45%, silicon dioxide 50% and diatomite 5%; The high-strength bentonite is prepared by grinding bentonite and sodium hydroxide at normal temperature, and the amount of sodium hydroxide accounts for 25% of the total mass of bentonite.

(10) Filtration: the deacidified hemp seed oil obtained in step (9) is filtered, and airtightly preserved.

Example 5

The preparation method that present embodiment provides to produce hemp seed oil, as shown in Figure 1, the method comprises:

(1) Cleaning: select fresh hemp seeds, clean and separate to remove impurities such as weeds, marl, stones, metals, etc.;

(2) High-frequency vacuum drying: adopt high-frequency vacuum drying equipment to adjust the hemp seed moisture after cleaning in step (1), and the high-frequency vacuum drying parameters are: frequency is 13.56MHz, voltage strength is 1000V/cm, vacuum tightness 3000Pa , the drying time is 55min, and the moisture content in the dried hemp seeds is 9.6%;

(3) Pre-husking: adopt laser moderate cutting to process the dried hemp seeds in step (2), the laser processing parameters are: power 50W, laser cutting rate 5mm/s, the laser slit width cut to the hemp seeds is 3.0mm;

(4) Shelling: Extrude and shell the hemp seeds after the pre-shelling in step (3) to obtain the hemp seeds and shells. The extrusion equipment is a toothed roller extrusion shelling machine, and the hemp seeds are shelled The rate is 98%;

(5) Positive pressure conditioning: adjust the moisture content of the hemp seeds obtained in step (4) under positive pressure conditions. The positive pressure conditioning process is: input the hemp seeds into the mixing device, evenly feed water, and continue stirring for 30 minutes. Be 60 revs/min, then change over to in the pressure-resistant container, set pressure as 3MPa, handle 15min, the hemp seed water content after tempering is 13%;

(6) Low-temperature pressing: use a mechanical press to press the hemp seeds in step (5) at a low temperature to obtain the hemp seed crude oil 1 and pressed hemp seed cakes, and the temperature is 70° C. during low-temperature pressing of the hemp seeds;

(7) High-pressure pulse subcritical extraction: adopt the high-pressure pulse subcritical extraction method to process the hemp seed cake in step (6), and obtain the hemp seed crude oil 2 and the hemp seed meal. The specific process of the high-pressure pulse subcritical extraction is: The pulse voltage is 35kv, the pulse time is 10μs, the extraction solvent is butane, the subcritical butane extraction pressure is 1.5MPa, the extraction time is 0.8h, and the extraction temperature is 50°C;

(8) Low-temperature crystallization degumming and dewaxing: adding 0.3% filter aid hemp seed cake powder to the hemp seed hair oil 1 obtained in step (6) and/or the hemp seed hair oil 2 obtained in step (7) Stir continuously for 30min with a stirring rate of 20 rpm; then cool down to 16°C with a stirring rate of 5 rpm and a cooling time of 6h, keep the temperature stable for another 4h, then add diatomaceous earth and use a pressure type Leaf filter for filtration;

(9) Moving bed type adsorption deacidification: add deacidification adsorbent in the moving bed reactor to carry out deacidification treatment to the degummed and dewaxed hemp seed oil obtained in step (8), to obtain deacidified hemp seed oil, wherein The acid adsorbent is prepared by mixing three raw materials: alkaline bentonite, silicon dioxide and diatomite, and the mass percentage of each raw material is: alkaline bentonite 55%, silicon dioxide 25% and diatomite 20%; The high-strength bentonite is prepared by grinding bentonite and sodium hydroxide at normal temperature, and the amount of sodium hydroxide accounts for 18% of the total mass of bentonite.

(10) Filtration: the deacidified hemp seed oil obtained in step (9) is filtered, and airtightly preserved.

Example 6

(1) Detect the deacidified hemp seed oil prepared in Example 1 of the present invention, and the main physical and chemical indicators of the obtained hemp seed oil are shown in Table 1.

The main physical and chemical index of table 1 hemp seed oil

(2) Detect the deacidified hemp seed oil prepared in Example 1 of the present invention, and the fatty acid composition of the obtained hemp seed oil is shown in Table 2.

Fatty acid composition of table 2 hemp seed oil

Test items Test results(%) testing base Myristic acid not detected GB/T17377-2008 Palmitic acid 6.3 GB/T17377-2008 palmitoleic acid 0.1 GB/T17377-2008 Heptadecanoic acid 0.1 GB/T 17377-2008 Heptadecenoic acid not detected GB/T17377-2008

stearic acid 2.9 GB/T17377-2008 Oleic acid 12.2 GB/T17377-2008 Linoleic acid 56.4 GB/T17377-2008 Linolenic acid 20.5 GB/T17377-2008 Arachidic acid 0.6 GB/T17377-2008 arachidonic acid 0.3 GB/T17377-2008 arachidienoic acid 0.1 GB/T17377-2008 behenic acid 0.2 GB/T17377-2008 other 0.3 GB/T17377-2008

(3) The hygienic index test was carried out on the deacidified hemp seed oil prepared in Example 1 of the present invention, and the hygienic index of the obtained hemp seed oil is shown in Table 3 below.

Hygienic index of table 3 hemp seed oil

(4) The micronutrient components of the deacidified hemp seed oil prepared in Example 1 of the present invention were tested, and the micronutrient components of the obtained hemp seed oil are shown in Table 4 below.

Table 4 Micronutrient composition of hemp seed oil

Unsaponifiable matter (%) 2.8 GB/T 5535.1-2008 Phytosterols (mg/100g) 66.6 GB/T 25223-2010 Chlorophyll (mg/kg) 16.71 SN/T 0801.21-2001 Total phenols (mgSA/100g)) 2.16 UV spectrophotometry Vitamin E(mg/kg) 576.5 NY/T 1598-2008

(5) The deacidified hemp seed oil prepared in Example 1 of the present invention is tested for the oxidation stability of hemp seed oil, and the test conditions are measured with reference to EN14112:2003; test conditions: 110° C.; air flow rate: 10 L/h, test The results are shown in Fig. 1, the oxidation induction period of deacidified hemp seed oil is 2.01h/110°C.

As can be seen from Table 1-4 and Fig. 1, adopt the hemp seed oil prepared by the preparation method in the present invention, its physicochemical index meets the relevant national standards, and the hygienic index meets the national standard, and the hemp seed oil is mainly composed of palmitic acid , palmitoleic acid, heptadecanoic acid, stearic acid, oleic acid, linoleic acid, linolenic acid, arachidic acid, arachidic acid, arachidienoic acid, behenic acid, etc., rich in phytosterols, Trace nutrients such as total phenols and vitamin E have good antioxidant properties, and the oxidation induction period of the deacidified hemp seed oil in the present invention is 2.01h/110°C.

The above-mentioned embodiment is a preferred embodiment of the present invention, but the embodiment of the present invention is not limited by the above-mentioned embodiment, and any other changes, modifications, substitutions, combinations, Simplification should be equivalent replacement methods, and all are included in the protection scope of the present invention.

Claims (5)

1. a preparation method of hemp seed oil is characterized in that comprising the following steps: (1) Cleaning and drying: select fresh hemp seeds, and use high-frequency vacuum drying after cleaning; (2) Pre-hulling: the hemp seeds after step (1) high-frequency vacuum drying are cut by laser to obtain pre-hulling hemp seeds; (3) Hulling: extruding and shelling the hemp seeds pre-husked in step (2) to obtain hemp seeds and shells; (4) Positive pressure conditioning: adjust the moisture content of the hemp seeds obtained in step (3) by adopting positive pressure conditioning; (5) Low-temperature pressing: using mechanical pressing equipment to perform low-temperature pressing on the hemp seeds obtained in step (4), to obtain hemp seed crude oil 1 and pressed hemp seed cakes; (6) High-pressure pulse subcritical extraction: the hemp seed cake obtained in step (5) is processed by high-pressure pulse subcritical extraction to obtain hemp seed crude oil 2 and hemp seed meal; (7) Low-temperature crystallization degumming and dewaxing: add filter aid to the hemp seed crude oil 1 obtained in step (5) and the hemp seed crude oil 2 obtained in step (6) for stirring, then uniformly cool down, and then conduct cooling Analysis and treatment, obtained degummed and dewaxed hemp seed oil through filtration; (8) Moving bed adsorption deacidification and filtration: add deacidification adsorbent to the moving bed reactor to deacidify the degummed and dewaxed hemp seed oil obtained in step (7) to obtain deacidified hemp seed oil, Sealed and preserved after filtration, the hemp seed oil is obtained; The parameters of the medium-high frequency vacuum drying in step (1) are: frequency 6 MHz-28 MHz, voltage intensity 1000 V/cm-3000 V/cm, vacuum degree 300 Pa-3000 Pa, and use high-frequency vacuum drying to reach the water content of the hemp seeds. The mass percentage is 7~11%; The various parameters when using laser cutting in step (2) are: power 6 W ~ 50 W, laser cutting speed 5 mm/s ~ 35mm/s, cutting to the slit width of hemp seeds is 0.5mm ~ 3.5mm ; The positive pressure tempering method described in step (4) is: input the hemp seed into the stirring equipment, evenly pour in water, continue stirring for 10min-30min, and the stirring rate is 60rpm-180rpm; In the pressure-resistant container, set the pressure at 0.2MPa-3MPa, treat for 15min-60min, and the moisture content of the hemp seed after conditioning is 7%-13%; When the high-voltage pulse subcritical extraction method is used in step (6) to process the hemp seed cake obtained in step (5), the parameters are: pulse voltage 5kv ~ 35kv, pulse time 10µs ~ 100µs, the solvent used in subcritical extraction It is butane, the subcritical extraction pressure is 0.3MPa～1.5MPa, the extraction time is 0.8h～4.0h, and the extraction temperature is 8℃～50℃; The specific process of low-temperature crystallization degumming and dewaxing treatment in step (7) is: adding filter aid to the hemp seed crude oil 1 obtained in step (5) and the hemp seed crude oil 2 obtained in step (6) Stir for 15min~30min, the stirring rate is 20rpm~80rpm, then uniformly cool down to 0℃~16℃, when the temperature is uniformly lowered, the stirring rate is 5rpm~35rpm, and the cooling time is 2h~6h After the temperature is stable, keep it for 4h-12h for cold analysis, and finally add diatomaceous earth and use a pressure leaf filter to filter to obtain degummed and dewaxed hemp seed oil, in which the filter aid is hemp seed cake powder. The amount of the hemp seed cake powder accounts for 0.05% to 0.3% of the total mass of the hemp seed crude oil 1 and the hemp seed crude oil 2. 2. The preparation method of hemp seed oil according to claim 1, characterized in that: in step (3), when the hemp seeds pre-hulled in step (2) are extruded and dehulled, the extrusion The pressing equipment is a toothed roller extrusion shelling machine, and the shelling rate of the hemp seeds is 85% to 98%. 3. The preparation method of hemp seed oil according to claim 1, characterized in that: in step (5), mechanical pressing equipment is used to press the hemp seed obtained in step (4) at a low temperature at a temperature of 25°C to 25°C. 70°C. 4. The preparation method of hemp seed oil according to claim 1, characterized in that: in step (8), add deacidification adsorbent to the degummed and dewaxed hemp seed obtained in step (7) in the moving bed reactor When the oil is deacidified, the degummed and dewaxed hemp seed oil is circulated in and out from bottom to top, and the deacidification adsorbent is from top to bottom. The deacidification temperature is 20°C to 70°C, and the adsorption time is 0.5h to 3.5h. 5. the preparation method of hemp seed oil according to claim 1 is characterized in that: described deacidification sorbent is made of alkaline bentonite, silicon dioxide and diatomite three kinds of raw materials, the quality of each raw material The percentage content is: 45% to 85% of alkaline bentonite, 10% to 50% of silicon dioxide and 5% to 20% of diatomite.