Preparation method of small-particle fructus cannabis

Abstract

The invention discloses a preparation method of small-particle fructus cannabis, and belongs to the technical field of traditional Chinese medicine treatment. The method comprises the following steps: removing impurities from hulled fructus cannabis; carrying out vacuum low-temperature pretreatment, and then carrying out hot air drying until the moisture content is 3-6%; uniformly mixing the dried fructus cannabis with inert powder, and crushing, wherein the particle size of the inert powder is 10-100 microns; grading and screening to obtain small-particle fructus cannabis with the particle size of 0.18 to 2.0 mm; finally, inert powder is removed through screening; wherein the vacuum low-temperature pretreatment conditions are as follows: the vacuum degree is 0.5-5.0 Pa, the temperature is 5-15 DEG C, and the time is 4-7 hours; the temperature of hot air drying is 125-135 DEG C. According to the method, the total yield is greater than 95%, and the proportion of the small-particle fructus cannabis is greater than or equal to 98%. The content of effective components can be guaranteed, the content of total fatty oil is larger than or equal to 170 mg / g, and the content of trigonelline is larger than or equal to 1.28%.

Description

Technical Field

[0001] This invention relates to the field of traditional Chinese medicine processing technology, specifically to a method for preparing small-particle hemp seeds. Background Technology

[0002] Hemp seeds are rich in nutrients, containing abundant unsaturated fatty acids, protein, vitamins, and minerals, and are widely used in the food, health product, and pharmaceutical industries. In practical applications, different scenarios have different requirements for the morphology and particle size of hemp seeds. The oil content of hemp seeds is 27.04%-37.67%, and the protein content is 20%-25%. Unsaturated fatty acids account for 77.55%-81.21% of the total fatty acid content in hemp seed oil, possessing antioxidant, lipid-lowering, and intestinal function-regulating effects. Hemp seed protein contains 65%-75% hemp globulin and 25%-37% hemp albumin, both of which are easily digestible complete proteins. Small-particle hemp seeds have unique advantages in instant beverages, baked goods ingredients, and some pharmaceutical preparations with strict particle size requirements, allowing for better dispersion and dissolution, thus improving product quality and taste.

[0003] For example, patent application number CN201610404972.6 discloses a functional composition for improving sleep and its application. The functional composition includes hemp seed powder, albumin polypeptide powder, lemon balm powder, and konjac gum; wherein the mass ratio of konjac gum, lemon balm powder, hemp seed powder, and albumin polypeptide powder is 1:10-20:20-32:110-200. For example, patent application number CN201811489235.6 discloses a meal replacement powder with lipid-lowering function and its use. This meal replacement powder is composed of at least activated oat dietary fiber powder, sea buckthorn powder, coix seed powder, poria cocos powder, polygonatum odoratum powder, and hemp seed powder. For example, patent application number CN201810067126.9 discloses a method for preparing hemp seed oil and its application, including the following steps: (1) Hemp seed pretreatment: drying, crushing and sieving hemp seeds to obtain hemp seed powder; (2) extraction: loading hemp seed powder into an extraction vessel and performing supercritical carbon dioxide extraction to obtain hemp seed oil; (3) decolorization: decolorizing with activated clay; (4) deacidification: deacidifying with alkaline clay; (5) purification: purifying hemp seed oil using molecular distillation.

[0004] However, because hemp seeds are rich in oil, if the drying process is not done properly, the oil is easily oxidized and rancid, affecting the quality and medicinal value of the hemp seeds.

[0005] Existing methods for processing hemp seeds are insufficient for efficiently and stably producing small-particle hemp seeds that meet specific particle size requirements. Traditional mechanical crushing methods, such as simple grinding and pulverizing, easily lead to hemp seeds sticking together and uneven particle size. Furthermore, the heat generated during processing can damage heat-sensitive nutrients in hemp seeds, reducing their nutritional value. Chemical treatment methods are not only costly but may also introduce chemical residues, affecting product safety. While some physical sorting methods can screen out small particles, their low yield cannot meet the needs of large-scale production. Currently used hot air drying easily causes uneven heating of hemp seeds, with localized overheating leading to nutrient loss and damage to the appearance due to high temperatures. Natural sun-drying is greatly affected by weather, has a long drying time, is prone to microbial growth, and may also result in contamination by dust and impurities. Therefore, developing a method that can efficiently and stably produce small-particle hemp seeds while preserving their nutritional components to the greatest extent is urgently needed. Summary of the Invention

[0006] This invention provides a method for preparing small-particle hemp seeds, which involves vacuum low-temperature pretreatment before drying to reduce the subsequent hot air drying time; and the addition of inert powder during pulverization to improve the yield of the pulverization and sieving processes. The technical solution provided by this invention is as follows: This invention provides a method for preparing small-particle hemp seeds. The method includes: removing impurities from the shelled hemp seeds; first, performing a vacuum low-temperature pretreatment to remove some moisture; then, hot air drying to a moisture content of 3-6%; mixing the dried hemp seeds with inert powder and then crushing them; wherein the amount of inert powder used is 3-10% of the weight of the hemp seeds, and the particle size of the inert powder is 10-100 μm; then, classifying and sieving to obtain small-particle hemp seeds of 0.18-2.0 mm; finally, sieving to remove the inert powder.

[0007] The inert powder has the following requirements: 1. The ingredients are stable and do not react with the components in hemp seeds; 2. It does not absorb the active ingredients in hemp seeds; 3. The particles are small and easy to separate from hemp seed powder; 4. It has a relatively high hardness and will not pulverize itself when hemp seeds are crushed; 5. Low cost and can be reused repeatedly.

[0008] 6. After being crushed, it is easy to separate from hemp seed granules.

[0009] The conditions for vacuum low-temperature pretreatment are: vacuum degree of 0.5-5.0 Pa, temperature of 5-15℃, and time of 4-7 h; the temperature for hot air drying is 125-135℃.

[0010] Given the high oil content of hemp seeds, without the addition of inert powder, they tend to stick together during crushing, making crushing and sieving difficult. Adding inert powder reduces the adhesion between hemp seeds and to the crushing equipment. Similarly, direct hot air drying of hemp seeds leads to changes in their oil content (specifically, a decrease in total fatty oil and trigonelline content); low-temperature drying fails to thoroughly dry them. Pre-treatment with vacuum at low temperatures removes a significant amount of moisture, reducing hot air drying time and allowing the hemp seeds to be dried before their oil content changes.

[0011] Specifically, the inert powder in the embodiments of the present invention is silicon dioxide powder.

[0012] Specifically, the impurity removal process is as follows: first, air separation, and then screening and impurity removal using a 5mm screen.

[0013] During hot air drying, the air velocity is 5-30 m / s.

[0014] Preferably, the vacuum drying conditions are: vacuum degree of 1 Pa, temperature of 10 °C, and time of 5 h; the hot air drying temperature is 130 °C, and the hot air flow rate is 10 m / s.

[0015] Specifically, the method for preparing small-particle hemp seeds provided by this invention includes the following steps: S1: After the hemp seeds are shelled, they are air-separated and screened through a 5mm sieve to remove impurities and large particles, thus obtaining pure hemp seeds.

[0016] S2: Hemp seeds are pretreated in a vacuum drying chamber with a vacuum degree of 0.5-5.0 Pa and a temperature of 5-15℃ for 4-7 hours; then they are sent into hot air for hot air drying until the moisture content is 3-6%; the temperature of hot air drying is 125-135℃ and the flow rate of hot air is 5-30m / s.

[0017] S3: Mix hemp seeds with 3-10% by weight of silica powder, the silica powder having a particle size of 10-100μm.

[0018] S4: Place the mixed material into a crusher for crushing.

[0019] S5: Collect small hemp seeds between 0.18mm and 2mm by sieving through 0.18mm and 2mm vibrating screens.

[0020] S6: Remove the silica powder from the material containing silica powder by sieving.

[0021] This patent has the following advantages: 1. By mixing and crushing hemp seeds with inert silica powder, the particle size of hemp seeds can be precisely controlled, producing small-particle hemp seeds with uniform particle size, preventing hemp seeds from sticking to the equipment and improving the yield.

[0022] 2. Inert powdered silica is used, which will not contaminate materials, resulting in good treatment effect and low investment and operating costs.

[0023] 3. Perform vacuum low-temperature pretreatment before drying to reduce the subsequent hot air drying time.

[0024] 4. It can reduce crushing time, thereby increasing production capacity.

[0025] 5. The total yield is greater than 95%, and the proportion of small hemp seed particles between 0.18mm and 2mm after crushing is greater than or equal to 98%.

[0026] 6. It can guarantee the content of effective ingredients, with total fatty oil content greater than or equal to 170mg / g and trigonelline content greater than or equal to 1.28%.

[0027] 7. Inert powdered silica can be reused repeatedly. Detailed Implementation

[0028] To make the objectives, technical solutions, and advantages of the present invention clearer, the embodiments of the present invention will be described in further detail below.

[0029] Example 1 Example 1 discloses a method for preparing small-particle hemp seeds, comprising the following steps: S1: Take 10kg of shelled hemp seeds, and remove impurities and large particles by air separation and screening through a 5mm sieve to obtain pure hemp seeds.

[0030] S2: Hemp seeds are pretreated for 5 hours in a vacuum drying chamber with a vacuum degree of 1 Pa and a temperature of 10 °C; then hot air is introduced for hot air drying until the moisture content is 4%; the hot air drying temperature is 130 °C and the hot air flow rate is 10 m / s.

[0031] S3: Mix hemp seeds with 5% by weight of silica powder, the silica powder having a particle size of 10-100μm.

[0032] S4: Place the mixed material into a crusher for crushing.

[0033] S5: Collect small hemp seeds between 0.18mm and 2mm by sieving through 0.18mm and 2mm vibrating screens.

[0034] S6: Remove the silica powder from the material containing silica powder by sieving.

[0035] Example 2 Example 2 discloses a method for preparing small-particle hemp seeds, comprising the following steps: S1: Take 10kg of shelled hemp seeds, and remove impurities and large particles by air separation and screening through a 5mm sieve to obtain pure hemp seeds.

[0036] S2: Hemp seeds are pretreated for 5 hours in a vacuum drying chamber with a vacuum degree of 1 Pa and a temperature of 10 °C; then hot air is introduced for hot air drying until the moisture content is 5%; the hot air drying temperature is 130 °C and the hot air flow rate is 10 m / s.

[0037] S3: Mix hemp seeds with 3.3% by weight of silica powder, the silica powder having a particle size of 10-100μm.

[0038] S4: Place the mixed material into a crusher for crushing.

[0039] S5: Collect small hemp seeds between 0.18mm and 2mm by sieving through 0.18mm and 2mm vibrating screens.

[0040] S6: Remove the silica powder from the material containing silica powder by sieving.

[0041] Example 3 Example 3 discloses a method for preparing small-particle hemp seeds, comprising the following steps: S1: Take 10kg of shelled hemp seeds, and remove impurities and large particles by air separation and screening through a 5mm sieve to obtain pure hemp seeds.

[0042] S2: Hemp seeds are pretreated in a vacuum drying chamber with a vacuum degree of 2 Pa and a temperature of 12 °C for 5.5 hours; then hot air is introduced for hot air drying until the moisture content is 4.5%; the hot air drying temperature is 132 °C and the hot air flow rate is 15 m / s.

[0043] S3: Mix hemp seeds with 4% by weight of silica powder, the silica powder having a particle size of 10-100μm.

[0044] S4: Place the mixed material into a crusher for crushing.

[0045] S5: Collect small hemp seeds between 0.18mm and 2mm by sieving through 0.18mm and 2mm vibrating screens.

[0046] S6: Remove the silica powder from the material containing silica powder by sieving.

[0047] Comparative Example 1 It is basically the same as Example 1, except that S2, S3 and S6 are not performed, that is, after drying (conventional hot air drying), it is directly pulverized and sieved in a conventional manner.

[0048] Comparative Example 2 The process is basically the same as in Example 1, except that in step S2, no low-temperature vacuum pretreatment is performed, and the product is directly dried with hot air until the moisture content reaches 4%.

[0049] Comparative Example 3 The process is basically the same as in Example 1, except that in step S2, low-temperature vacuum pretreatment is not performed, and the product is directly dried with hot air until the moisture content reaches 4%. Steps S3 and S6 are not performed; that is, after drying, the product is directly pulverized and sieved using conventional methods.

[0050] The contents of total fatty oil and trigonelline in the raw hemp seed slices, the hemp seed samples of Examples 1-3 and Comparative Examples 1-3 were determined respectively.

[0051] The method for determining the total fatty oil content is based on the Soxhlet extraction method (General Chapter 0713 of the Chinese Pharmacopoeia): Take about 100g of hemp seed sample, accurately weigh it, place it in a Soxhlet extractor, add an appropriate amount of petroleum ether (60-90℃), heat and reflux for extraction (5 hours) until the fatty oil is completely extracted, collect the extract, place it in an evaporating dish that has been dried to constant weight, evaporate it to dryness in a water bath at low temperature, dry it at 100℃ for 1 hour, transfer it to a desiccator, cool it for 30 minutes, accurately weigh it, and calculate the result. Trigonelline (C7H7NO2) was determined by high performance liquid chromatography (General Chapter 0512, Chinese Pharmacopoeia 2020 Edition): Chromatographic conditions and system suitability test The column was packed with octadecylsilane-bonded silica gel; the mobile phase was methanol-0.05% sodium dodecylbenzenesulfonate solution-glacial acetic acid (20:80:0.1) at a flow rate of 1 ml / min; the column temperature was 30℃. The detection wavelength was 265 nm, and the theoretical plate number, calculated based on the trigonelline peak, should be no less than 4000.

[0052] Preparation of reference solution Take an appropriate amount of trigonelline reference standard, accurately weigh it, and add 50% methanol to prepare a solution containing 20 μg per ml.

[0053] Preparation of test solution Take about 0.2g of the powder (passed through a No. 3 sieve), accurately weigh it, place it in a stoppered conical flask, accurately add 25ml of 50% methanol, seal tightly, weigh it, sonicate (power 250W, frequency 40kHz) for 30 minutes, cool it, weigh it again, add the weight, shake well, filter it, and collect the filtrate to obtain the product.

[0054] The assay method involves precisely pipetting 10 μl of the reference solution and the test solution into the liquid chromatograph and measuring the results, which are shown in Table 1.

[0055] Table 1

[0056] As shown in Table 1, compared to the comparative example, the present invention requires less time to grind hemp seeds into a finer powder, resulting in a higher yield. Compared to the comparative example, the present invention also shows less loss of active ingredients (total fatty oil and trigonelline). As can be seen from Comparative Example 3 and Example 1, conventional grinding methods require extended grinding time (even with extended grinding time, the yield is not high), and the prolonged grinding process leads to the loss of total fatty oil and trigonelline, with the loss of trigonelline being particularly significant.

[0057] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for preparing small-particle hemp seeds, characterized in that, The method includes: After shelling, the hemp seeds are cleaned of impurities; they are first pretreated under vacuum at low temperature, and then dried with hot air until the moisture content is 3-6%; the dried hemp seeds are mixed with inert powder and then crushed, the amount of inert powder being 3-10% of the weight of the hemp seeds, and the particle size of the inert powder being 10-100μm; then graded and sieved to obtain small hemp seed particles of 0.18-2.0mm; finally, the inert powder is removed by sieving. The conditions for vacuum low-temperature pretreatment are: vacuum degree of 0.5-5.0 Pa, temperature of 5-15℃, and time of 4-7 h; the temperature for hot air drying is 125-135℃.

2. The method for preparing small-particle hemp seeds according to claim 1, characterized in that, The inert powder is silicon dioxide powder.

3. The method for preparing small-particle hemp seeds according to claim 1, characterized in that, The impurity removal process is as follows: first, air separation, and then screening and impurity removal using a 5mm screen.

4. The method for preparing small-particle hemp seeds according to claim 1, characterized in that, During hot air drying, the air velocity is 5-30 m / s.

5. The method for preparing small-particle hemp seeds according to claim 4, characterized in that, The conditions for vacuum low-temperature pretreatment are: vacuum degree of 1 Pa, temperature of 10℃, and time of 5 h; the temperature of hot air drying is 130℃, and the flow rate of hot air is 10 m / s.

6. The method for preparing small-particle hemp seeds according to claim 1, characterized in that, The method includes the following steps: S1: Take the shelled hemp seeds, and then remove impurities and large particles by air separation and screening with a 5mm sieve to obtain pure hemp seeds; S2: Hemp seeds are pretreated in a vacuum drying chamber with a vacuum degree of 0.5-5.0 Pa and a temperature of 5-15℃ for 4-7 hours; then they are sent into hot air for hot air drying until the moisture content is 3-6%; the hot air drying temperature is 125-135℃ and the hot air flow rate is 5-30m / s. S3: Mix hemp seeds with 3-10% by weight of silica powder, the silica powder having a particle size of 10-100μm; S4: Place the mixed material into a crusher for crushing; S5: Collect small hemp seeds between 0.18mm and 2mm by sieving through 0.18mm and 2mm vibrating screens; S6: Remove the silica powder from the material containing silica powder by sieving.

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