Low-temperature freezing squeezing extraction method of plant stock solution

Abstract

The invention provides a method for extracting a plant stock solution through low-temperature freezing and squeezing. The method comprises the following steps: carrying out pretreatment such as cleaning on a squeezed object; soaking, spreading and freezing at subzero; squeezing, standing and then separating. The upper layer is oil, and the lower layer is water, oil residues and other substances; and treating the oily raw solution, the aqueous raw solution and the residue which can be continuously utilized as finish machining raw materials. The preparation method is small in nutrient loss, high in extraction efficiency, free of chemical solvent residues and high in effective component content.

Description

Technical Field

[0001] The invention belongs to the technical field of extraction and preparation, and specifically relates to a low-temperature freezing and pressing extraction method of plant stock solution. Background Art

[0002] For the extraction of effective components of agricultural plants, the commonly used methods in the current extraction industry include water enzyme method, hot pressing method, decoction method, soaking method, percolation method, reflux method, steam distillation method, etc. Decoction method is a traditional method. It is a common method to extract the components contained in agricultural plants by heating and boiling them for a certain period of time with water as solvent. It is suitable for medicinal materials whose effective components are soluble in water and relatively stable to heat. The soaking method can be divided into: cold soaking method, hot soaking method, and heavy soaking method. The percolation method is a method in which the crude powder of agricultural plants is placed in a percolator, the solvent is continuously added from the upper part of the percolator, and the percolation liquid continuously flows out from the lower part, thereby leaching the effective components. The reflux method is a method in which volatile organic solvents such as ethanol are used to extract the components of agricultural plants, the leaching liquid is heated and distilled, and the volatile solvent is distilled and condensed, and then repeatedly flows back to the extractor to extract the agricultural plants, and this cycle is repeated until the effective components are completely refluxed and extracted. In addition to the disadvantages of large loss of effective ingredients, long cycle, multiple processes, and low extraction efficiency, these traditional extraction methods also have problems such as a large number of impurities.

[0003] Patent CN115109640A proposes a low-temperature freezing and pressing method for wheat germ oil extraction, which purifies fresh wheat germ to obtain finished wheat germ oil through sorting, granulation, maturation, pressing, drying, winterization, fine filtration and other steps; but its extraction efficiency needs to be enhanced. Patent CN113549493A provides a low-temperature freezing and pressing low-temperature freezing extraction tea seed oil production process, which is obtained through cleaning and disinfection, drying, cleaning, screening, rolling, frying, cold rolling, filtering and separation, and standing to take liquid; although the oil yield of tea oil seeds is improved, there is no specific oil yield, the absorption of water soaked in tea seeds acts on the shell, freezing is used to break the shell of tea seeds (not squeezing), soaking and freezing are not related to squeezing, and the process is complicated and costly. Patent CN107136227B provides a low-temperature frozen pressed peanut cake flavor extract and a method for using the same, wherein the flavor extract is obtained by low-temperature freezing, one-time pressing, baking, and subcritical fluid extraction; the method is simple to operate, has mild conditions, and a short processing time, but the extraction efficiency is poor.

[0004] In the prior art, most of the extraction processes for effective components of crops, plants, etc. have problems such as large loss of certain effective components and low extraction efficiency. Therefore, it is of practical significance to develop a low-temperature freezing and freezing pressing process. Summary of the invention

[0005] The purpose of the present invention is to provide a low-temperature freezing and squeezing extraction method and application of plant stock solution, which extracts components through pretreatment, soaking, freezing, freezing and squeezing, and extraction, physical separation and other processes. The method for preparing stock solution has a wide range of applications (directly applicable to edible oil extraction and protein extraction at the same time), high content of effective components, small loss of nutrients, no chemical solvent residue and high temperature variation.

[0006] The method for preparing the stock solution includes the following working principles and steps: (i) temperature conditions, the temperature of the entire extraction process is -30℃~40℃ (ii) water infiltration must enter the tissue of the squeezed material, and the infiltration must use clean water ≤40℃, and the squeezed material cannot be deteriorated (iii) squeezing conditions, the squeezed material is squeezed under freezing conditions, and any squeezed material is kept at a temperature of <60℃ during the squeezing process (iv) separation conditions, the liquid and residue after squeezing are separated by physical methods, and the liquid types after squeezing are separated by physical methods. The separation method cannot have conditions and situations of ≥60℃. 2. Steps (i) Wash the squeezed material; (ii) Soak (including the possible need to reduce the size of the material or crush it before soaking); (iii) Spread, freeze, (iv) Use squeezing or re-fine crushing methods to extract the stock solution and solid-liquid separation; (v) Filter the residue and extract, and repeat the third and fourth steps. (VI) Mix the liquids obtained in (IV) and (V) above and centrifuge them; filter and separate the oily stock solution and the aqueous stock solution. Treat the oily stock solution, the aqueous stock solution and the recyclable residue as fine processing raw materials. This preparation method has little loss of nutrients, high extraction efficiency, no chemical solvent residue, and high content of effective ingredients.

[0007] In order to achieve the above object, the present invention provides the following technical solutions: A low-temperature freezing and squeezing extraction method of plant stock solution comprises the following steps: S1: cleaning the squeezed material; S2: Soak the material obtained in step S1 in water with a volume ratio of ≧1:0.5 and a temperature of ≦30°C, so that water can penetrate into the material tissue; (Note: the time should be ≧30 minutes, and care should be taken to prevent material A from deteriorating) Method 1: In order to improve the efficiency of water penetrating into the material structure, the powder material is crushed to obtain material A (material A particles ≥ 500 mesh are preferred, such as sesame, peanuts, etc.); Method 2: Reduce the size of the powder to obtain material A (the size should be determined according to the needs of pressing, such as coconut, avocado and olive, etc.) S3. Spread the soaked material A flat (the most suitable thickness is ≤3 cm), freeze it at a temperature <0°C until it freezes (15 min ≤ ≤ 60 min is preferred), and obtain material B; S4: extract the original liquid of material B at a temperature ≤ 30°C, separate the solid-liquid filter to take the liquid as the original liquid, take the liquid as the filtrate A, and take the solid as the filter residue A; Method 1: Use a press to squeeze material B. Note: It is necessary to ensure that the entire squeezed material is frozen at ≤30℃ during squeezing. Advantages: good solid-liquid separation. Disadvantages: easy to heat up. Method 2: Use a pulverizer to grind material B into 500 mesh. Advantages: not easy to heat up, disadvantages: increases the difficulty of solid-liquid separation.

[0008] S5: Add clean water with a solid-liquid ratio of ≧1:1 and a temperature of ≦30°C to the residue A and soak it (preferably for ≦60 minutes), repeat S3 to obtain material C, repeat material CS4, filter and take the liquid as filtrate B, and take the solid as residue B; Note: Repeat steps S3 and S4 until the content of the main extract of the filter residue B is appropriate. The filtrate obtained from each filtration is B. S6: Mix the filtrate A obtained in step S4 and the filtrate B obtained in step S5 to obtain a mixed solution, S7: Add clean water to the mixed liquid (preferably in a volume ratio of 1:1) and separate it using a centrifuge. After standing (standing time ≥ 30 minutes), the mixed liquid is separated into sediment, aqueous stock solution and oily stock solution.

[0009] Note: The centrifugal speed is determined according to the separation requirements. For example, the separation of aqueous stock solution and oily stock solution is done by centrifugation in a low-speed centrifuge (speed 0-3000r / min). (5-10min is appropriate) S8: The aqueous original solution, the oily original solution and the sediment are respectively extracted by physical means, and the sediment and the filter residue B are mixed to obtain the pressed residue. Note: The physical methods of this step include condensation separation, stratification and diversion, etc., but the temperature must not be increased by ≥50℃.

[0010] S9: The aqueous raw solution, the oily raw solution and the pressed residues extracted by physical methods are used as raw materials for fine processing.

[0011] Application of any of the above methods in peanut, coconut and olive extracts.

[0012] Compared with the prior art, the advantages and beneficial effects of the present invention are: 1. The present invention increases the moisture in the plant tissue and the number of ice crystals in the squeezed plant tissue; the plant is frozen into crystals inside and outside the cells by soaking, and the ice crystals are used to destroy the plant cell walls by freezing treatment. The crystals and the mutual friction between the crystals increase the damage to the extracted tissue and improve the extraction rate; at the same time, squeezing increases friction, further destroys the plant cell walls, and the cell walls of the plant cells are lysed and completely released. The treatment is completely carried out under low-temperature freezing and physical conditions without any chemical products such as organic solvents.

[0013] 2. The present invention crushes the plants into powder by freezing and squeezing. The ice crystals are crushed into low-temperature frozen water, which is conducive to the crushing and crushing of the plants, and ensures that the crushing (crushing) is carried out in a low-temperature freezing environment; it can retain almost all nutrients and is rich in polyunsaturated fatty acids; it effectively prevents the fermentation and deterioration of the substances. The oily substances in the stock solution are extracted by pulse salting out, gradient cooling and other methods. DETAILED DESCRIPTION

[0014] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0015] Example 1 This embodiment provides a low-temperature freezing and squeezing extraction method of plant stock solution, comprising the following steps: S1: Wash the plant raw material to remove impurities, crush it to 100-300 mesh, and obtain material A; soak material A in distilled water with a volume ratio of 1:1 and a temperature of 30°C for 35 minutes, then spread the soaked material A flat for 2 cm, and freeze it at a temperature of -30°C for 15 minutes to obtain material B; S2: The material B obtained in step S1 is squeezed at a temperature of 30°C, and the liquid is separated by a 400-mesh filter to obtain the original liquid; the liquid is taken as the filtrate A, and the solid is taken as the filter residue A; the filtrate A is allowed to stand; S3: Add clean water in a volume ratio of 1:1 to the solid residue A, stir with a wall-breaking machine at a temperature of 30°C for 2 minutes; cool and let stand for 30 minutes, filter with an 800-mesh filter, take the liquid as filtrate B, and take the solid as residue B; let filtrate B stand; S4: Mix the filtrate B and the filtrate A to obtain filtrate C; Mix the filter residue A and the filter residue B to obtain filter residue C; S5: Filtrate C was stirred in a wall breaking machine at a speed of 900 r / min for 2 min; S6: Let the peanut oil solution stand at 5°C until it solidifies and then take it out; the embodiment of using the present technology to produce peanut oil by low-temperature freezing and freezing pressing is completed. Take a sample to determine the oil content of the filter residue C.

[0016] The filtered colorless transparent aqueous solution was added to a 5% sodium chloride aqueous solution, stirred with a juicer at 300 r / min, and left to stand to obtain white particles, which were detected to be protein substances. The filter residue C can be used as an edible material after being dried by baking.

[0017] Example 2 This embodiment provides a low-temperature freezing and squeezing extraction method of plant stock solution, comprising the following steps: S1: Wash the plant raw material to remove impurities, crush it to 80-100 mesh, and obtain material A; soak material A in distilled water with a volume ratio of 1:0.5 and a temperature of 30°C for 25 minutes, then spread the soaked material A flat for 3 cm, and freeze it at a temperature of -45°C for 20 minutes to obtain material B; S2: The material B obtained in step S1 is squeezed at a temperature of 30°C, and the liquid is separated by a 400-mesh filter to obtain the original liquid; the liquid is taken as the filtrate A, and the solid is taken as the filter residue A; the filtrate A is allowed to stand; S3: Add clean water in a volume ratio of 1:1 to the solid residue A, stir with a wall-breaking machine at a temperature of 30°C for 2 minutes; cool and let stand for 30 minutes, filter with an 800-mesh filter, take the liquid as filtrate B, and take the solid as residue B; let filtrate B stand; S4: Mix the filtrate B and the filtrate A to obtain filtrate C; Mix the filter residue A and the filter residue B to obtain filter residue C; S5: Filtrate C was stirred in a wall breaking machine at a speed of 900 r / min for 2 min; S6: Let the peanut oil solution stand at 10°C until it solidifies and is taken out; the embodiment of using the present technology to produce peanut oil by low-temperature freezing and freezing pressing is completed. Take a sample to determine the oil content of the filter residue C.

[0018] The filtered colorless transparent aqueous solution was added to a 5% sodium chloride aqueous solution, stirred with a juicer at 300 r / min, and left to stand to obtain white particles, which were detected to be protein substances. The filter residue C can be used as an edible material after being dried by baking.

[0019] Example 3 This embodiment provides a low-temperature freezing and squeezing extraction method of plant stock solution, comprising the following steps: S1: Wash the plant raw material to remove impurities, crush it to 60-80 mesh, and obtain material A; soak material A in distilled water with a volume ratio of 1:0.8 and a temperature of 30°C for 30 minutes, then spread the soaked material A flat with a thickness of 5 cm, and freeze it at a temperature of -25°C for 30 minutes to obtain material B; S2: The material B obtained in step S1 is squeezed at a temperature of 30°C, and the liquid is separated by a 400-mesh filter to obtain the original liquid; the liquid is taken as the filtrate A, and the solid is taken as the filter residue A; the filtrate A is allowed to stand; S3: Add clean water with a volume ratio of 1:1.05 to the solid residue A, stir with a wall breaking machine at a temperature of 30°C for 3 minutes; cool and stand for 30 minutes, filter with an 800-mesh filter, take the liquid as filtrate B, and take the solid as residue B; let the filtrate B stand; S4: Mix the filtrate B and the filtrate A to obtain filtrate C; Mix the filter residue A and the filter residue B to obtain filter residue C; S5: Filtrate C was stirred in a wall breaking machine at a speed of 900 r / min for 2 min; S6: Let the peanut oil solution stand at 8°C until it solidifies and then take it out; the embodiment of producing peanut oil by low-temperature freezing and freezing pressing using the present technology is completed. Take a sample to determine the oil content of the filter residue C.

[0020] The filtered colorless transparent aqueous solution was added to a 5% sodium chloride aqueous solution, stirred with a juicer at 300 r / min, and left to stand to obtain white particles, which were detected to be protein substances. The filter residue C can be used as an edible material after being dried by baking.

[0021] Comparative Example 1 The difference between this comparative example and Example 1 is that no soaking treatment is performed in step S1, and the other steps are the same.

[0022] Comparative Example 2 The difference between this comparative example and Example 1 is that the soaking time in step S1 is 10 min, and the other steps are the same.

[0023] Comparative Example 3 The difference between this comparative example and Example 1 is that the soaking time in step S1 is 50 min, and the other steps are the same.

[0024] Comparative Example 4 The difference between this comparative example and Example 1 is that the powder is crushed to 200-300 mesh in step S1, and the other steps are the same.

[0025] Comparative Example 4 The difference between this comparative example and Example 1 is that the powder is crushed to 400-500 mesh in step S1, and the other steps are the same.

[0026] Comparative Example 5 The difference between this comparative example and Example 1 is that the freezing temperature in step S1 is -5°C, and the other steps are the same.

[0027] Comparative Example 6 The difference between this comparative example and Example 1 is that the freezing temperature in step S1 is -10°C, and the other steps are the same.

[0028] Performance Test: The oil release rate of the squeezed material in the embodiment (Note: refers to the reduction rate of the oil content of the original crop residue after the crop is squeezed by this method, calculated as: the oil content of the original crop - the oil content of the residue ÷ the oil content of the original crop × 100%); the effective ingredient extraction rate (calculated as: the effective ingredient content of the original crop - the effective ingredient content of the residue ÷ the effective ingredient content of the original crop × 100%).

[0029] Peanuts and shredded coconut were used as raw materials, respectively, and the extraction effects were tested using the above-mentioned embodiment and comparative example methods. The test results are shown in the following table.

[0030] Table 1 Performance test results

[0031] From the above performance test results, it can be seen that the efficiency and grease release rate of Examples 1-3 are relatively good; in particular, the comprehensive performance of Example 3 is the most outstanding. However, since Comparative Examples 1-6 do not adopt the necessary technical solutions, their corresponding performance tests are significantly worse than those of the Examples. The above experimental results further prove the importance of the technical solutions defined in the present invention for its technical effects.

[0032] The above is a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for low temperature freezing and squeezing extraction of plant stock solution, characterized in that: The steps include: S1: cleaning the squeezed material; S2: Soak the material obtained in step S1 in water with a volume ratio of ≧1:0.5 and a temperature of ≦30°C, so that water penetrates into the material tissue; S3: Spread the soaked material A flat, and freeze it at a temperature <0°C until it freezes to obtain material B; S4: extract the original liquid of material B at a temperature ≤ 30°C, separate the solid-liquid filter to take the liquid as the original liquid, take the liquid as the filtrate A, and take the solid as the filter residue A; S5: Add water with a solid-liquid ratio of ≧1:1 and a temperature of ≦30°C to the residue A to soak it, repeat S3 to obtain material C, repeat material CS4, filter and take the liquid as filtrate B, and take the solid as residue B; S6: Mix the filtrate A obtained in step S4 and the filtrate B obtained in step S5 to obtain a mixed solution, S7: adding water to the mixed solution and separating it by a centrifuge, and then letting it stand to separate the sediment, aqueous original solution liquid and oily original solution liquid from the mixed solution; S8: extracting the aqueous original solution, the oily original solution and the sediment by physical means respectively, and mixing the sediment and the filter residue B to obtain the pressed residue; S9: The aqueous raw solution, the oily raw solution and the pressed residues extracted by physical methods are used as raw materials for fine processing.

2. The low-temperature freezing and squeezing extraction method of a plant stock solution according to claim 1, characterized in that: In step S1, the pressed material is washed and crushed. Specifically, the pressed material, i.e., the agricultural and plant products, is washed to remove impurities and crushed to 300-500 meshes.

3. The low-temperature freezing and squeezing extraction method of a plant stock solution according to claim 1, characterized in that: In step S2, material A is soaked in clean water with a volume ratio of ≧1:0.5 and a temperature of ≦30°C, and then the soaked material A is spread out and frozen at a temperature of <0°C until it freezes for 5min≦≦≦60min to obtain material B.

4. The low-temperature freezing and squeezing extraction method of a plant stock solution according to claim 1, characterized in that: Step S2 specifically comprises pressing material B at a low temperature of ≤30°C, separating the solid and the liquid to obtain the liquid as the stock solution; adding distilled water with a volume ratio of 1:2 to the stock solution, stirring at a rate of 400r / min for 8min at a temperature of 45°C; cooling and standing for 40min, filtering and obtaining the liquid as the filtrate A, and obtaining the solid as the filter residue A.

5. The low-temperature freezing and squeezing extraction method of a plant stock solution according to claim 1, characterized in that: Step S3 is specifically as follows: add clean water with a solid-liquid ratio of ≧1:1 and a temperature of ≦30°C to the filter residue A in step S4, soak it for ≦60 min, spread it flat with a thickness of 1~3 cm, freeze it at a temperature of <0°C until it freezes for ≦60 min to obtain the material, freeze it at a low temperature of ≦30°C by pressing or re-fine grinding to extract the original liquid, take the liquid as the filtrate B through a filter screen, take the solid as the filter residue B, implement solid-liquid diversion, and take the liquid as the original liquid.

6. The low-temperature freezing and squeezing extraction method of a plant stock solution according to claim 1, characterized in that: Step S4 is specifically as follows: adding distilled water with a solid-liquid ratio of 1:10 to the filter residue B in step S3, and centrifugally stirring at a rate of 5000 r / min for 6 minutes at a temperature of 25°C; cooling and standing for 35 minutes, filtering and taking the liquid as filtrate C, and taking the solid as filter residue C.

7. The method for low-temperature freezing and freezing-pressing extraction of plant stock solution according to claim 1, characterized in that: In step S7, clean water is added in a volume ratio of 1:1, and the mixture is separated by centrifuge and allowed to stand for 30 minutes to separate the sediment, aqueous original solution, and oily original solution.

8. The method for low-temperature freezing and squeezing of plant liquid according to claim 1, characterized in that: Step S8 specifically comprises: extracting the aqueous original solution, the oily original solution and the sludge respectively by physical means, mixing the sludge and the filter residue B to obtain the pressed residue; the physical means of this step include freezing separation, stratification and diversion, etc., but the temperature shall not be ≧50°C; the aqueous original solution, the oily original solution and the pressed residue respectively extracted by physical means are used as fine processing raw materials.

9. Use of the method according to any one of claims 1 to 8 in peanuts.

10. Application of the method according to any one of claims 1 to 8 in coconut.

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