Preparation method and application of sacha inchi oil

Abstract

The invention relates to the field of extraction of sacha inchi oil, in particular to a preparation method and application of sacha inchi oil, and aims to solve the problems of large loss of heat-sensitive components, solvent residue and low oil yield in the traditional process. The ratio of cellulase to pectinase to xylanase to lipase is 3: 2: 1: 0.5, and carrying out enzymolysis for 2-3 hours at the pH value of 4.5-5.5 and the temperature of 45-50 DEG C; the obtained enzymolysis product is subjected to 28-40kHz ultrasonic treatment for 20-30 minutes, and then is subjected to two-stage gradient squeezing (pre-squeezing at 50-55 DEG C to final squeezing at 35-40 DEG C) in combination with 0.1 mu m ceramic membrane filtration, so that efficient oil extraction and active ingredient protection are realized. The oil yield of the sacha inchi oil is increased to 50.0%, the content of alpha-linolenic acid is larger than or equal to 42%, the content of vitamin E reaches 158 mg / 100 g, no solvent is left, and the sacha inchi oil is suitable for the fields of functional food and cosmetics.

Description

Technical Field

[0001] The present invention relates to the field of extraction of Sacha Inchi oil, and particularly to a preparation method and application of Sacha Inchi oil. Background Art

[0002] Sacha Inchi oil is rich in unsaturated fatty acids (α-linolenic acid > 45%) and vitamin E. Unsaturated fatty acids can reduce blood lipids such as triglycerides and low-density lipoproteins, reduce the risk of atherosclerosis, and maintain vascular health; they can also inhibit pro-inflammatory factors (such as TNF-α, IL-6), promote the integrity of brain cell membranes, and improve cognitive function; enhance the skin barrier, relieve dryness and inflammation, and contribute to skin repair. Vitamin E has antioxidant effects, can scavenge free radicals, delay the oxidative rancidity of oils; can also inhibit ultraviolet-induced degradation of skin collagen, protect the skin; can also enhance the activity of T cells and perform immune regulation. Therefore, Sacha Inchi oil can be used in cosmetics, health products and functional foods.

[0003] However, the existing extraction technologies have obvious defects: when using the traditional pressing method for extraction, not only is the oil yield low (< 30%), but also due to high temperature, the oxidation loss of α-linolenic acid is > 20%; single pretreatment technology: the cell wall breaking efficiency is insufficient (cell rupture rate < 65%), resulting in low oil yield and loss of key nutrients such as α-linolenic acid and vitamin E, high energy consumption, and low process efficiency. When using the traditional aqueous enzymatic method for extraction, due to only using a double-enzyme system of cellulase + pectinase (comparative document CN11211134A), the enzymatic hydrolysis time is too long, and there is a lack of physical synergistic cell wall breaking, resulting in low process efficiency; using organic solvents for extraction will cause solvent residues; the traditional double-enzyme method has incomplete enzyme systems and inappropriate pH, resulting in incomplete cell wall breaking, while the present invention realizes the degradation of all components of the cell wall through a four-enzyme composite system, optimizes the activity of xylanase at acidic pH, and uses ultrasonic physical assistance to shorten the treatment time.

[0004] Therefore, in order to overcome the above defects in the existing technology, there is an urgent need for a new method for preparing Sacha Inchi oil, which can achieve high-efficiency cell wall breaking and oil yield improvement, efficient retention of active ingredients, green and efficient production process, and significant improvement in product quality. Summary of the Invention

[0005] To solve or partially solve the problems existing in the related technologies, the present application provides a method for preparing Sacha Inchi oil, which can improve the oil yield of Sacha Inchi and retain active ingredients.

[0006] On the one hand, the present application provides a method for preparing Sacha Inchi oil, and the method includes the following steps:

[0007] 1) After sequentially crushing, sieving and drying Sacha Inchi kernels, crushed Sacha Inchi kernels are obtained;

[0008] 2) Mix the crushed Physic nut kernels obtained in 1) with water, add a compound enzyme preparation, oscillate at pH 4.5 - 5.5 and 45 - 50 °C for 1 h, and then add lipase and continue to oscillate for 1 - 2 h to obtain an enzymatically hydrolyzed product.

[0009] The compound enzyme preparation is cellulase:pectinase:xylanase, and the mass ratio is 3:2:1.

[0010] 3) Ultrasonically treat the enzymatically hydrolyzed product obtained in 2) to obtain ultrasonically treated material.

[0011] 4) Gradient low-temperature press the material in 3) to obtain crude oil. The gradient low-temperature press is divided into a first stage and a second stage.

[0012] The conditions of the first stage are pre-pressing at 50 - 55 °C and a pressure of 15 - 20 MPa for 10 min.

[0013] The conditions of the second stage are final pressing at 35 - 40 °C and the pressure increased to 30 - 35 MPa.

[0014] 5) Filter the crude oil to obtain a filtrate, which is Physic nut oil.

[0015] Furthermore, the moisture content of the crushed Physic nut kernels is below 6%.

[0016] Furthermore, the oscillation amplitude is 5 - 10 μm and the frequency is 15 - 20 Hz.

[0017] Furthermore, the ultrasonic frequency is 28 - 40 kHz and the time is 20 - 30 min.

[0018] Furthermore, the addition amount of the compound enzyme preparation in 2) is 0.8% - 1.2% of the mass of the crushed Physic nut kernels, and the addition amount of lipase is 0.1% of the mass of the crushed Physic nut kernels.

[0019] Furthermore, the filtration in 5) is carried out with a 0.1 μm ceramic membrane at 25 - 30 °C.

[0020] On the other hand, the present application also provides an extraction method for Physic nut oil. The extraction method includes:

[0021] Take the residue after pressing in steps 1) - 4) of the above method, carry out supercritical CO2 extraction on the residue to obtain an oil phase, combine it with the crude oil in 4), and filter to obtain a filtrate, which is Physic nut oil.

[0022] Furthermore, the conditions of the supercritical CO2 extraction process are a pressure of 25 - 30 MPa, a temperature of 40 ± 1 °C, a CO2 flow rate of 25 kg / h, and an extraction time of 1.5 h.

[0023] On the other hand, the present application also provides the use of Sacha inchi oil obtained according to the above preparation method or the above extraction method in functional foods.

[0024] On the other hand, the present application also provides the use of Sacha inchi oil obtained according to the above preparation method or the above extraction method in cosmetics.

[0025] Beneficial effects

[0026] 1. The preparation method of Sacha inchi oil provided by the present invention combines enzymatic hydrolysis-ultrasonic synergistic cell wall breaking, gradient low-temperature pressing and physical purification, significantly improving the oil extraction efficiency to 45.8%-53.1%, and significantly increasing the retention rate of thermosensitive active ingredients.

[0027] 2. The method provided by the present invention uses ultrasonic treatment after enzymatic hydrolysis instead of pretreatment, and the synergistic effect of ultrasonic treatment after enzymatic hydrolysis:

[0028] (1) Significantly improved cell wall breaking efficiency: Enzymatic hydrolysis pretreatment partially degrades cell wall polysaccharides (such as cellulose, pectin, etc.), weakening the integrity of the cell structure; subsequent ultrasonic waves (28-40 kHz) generate cavitation effects, forming microjets and shock waves in the liquid, further tearing the weakened cell wall;

[0029] (2) Accelerated oil release rate: The cavitation effect of ultrasonic waves forms a pressure difference inside and outside the cells, promoting the diffusion of intracellular oil into the medium; the bound oil in the enzymatic hydrolysis products is more easily released due to mechanical force;

[0030] (3) Protective extraction of active ingredients (low-temperature synergy): Ultrasonic treatment is completed within 20-30 minutes, and the whole process temperature ≤ 50°C, avoiding the oxidation of thermosensitive ingredients (such as α-linolenic acid, vitamin E).

[0031] 3. The method provided by the present invention uses gradient low-temperature pressing. Through the gradient change of temperature-pressure, it not only ensures the oil output efficiency but also maximizes the retention of active ingredients. Pre-pressing stage (50-55°C / 15-20 MPa): Soften the cell structure and release free oil. Final pressing stage (35-40°C / 30-35 MPa): Extract bound oil at low temperature and high pressure, and low temperature inhibits the activity of phospholipase to avoid oil hydrolysis. The temperature difference design in the two stages can reduce the oxidation rate of α-linolenic acid and greatly improve the retention rate of vitamin E.

[0032] 4. The residue after pressing of the present invention is subjected to supercritical extraction. Through low-temperature and high-pressure CO2 fluid, the residual bound oil in the pressed residue is efficiently extracted, the oil yield is increased to 53.1%, and at the same time, the retention rate of α-linolenic acid > 94% and the vitamin E content of 158 mg / 100 g are maintained. The supercritical technology avoids the residue of chemical solvents.

[0033] It should be understood that the above general description and the following detailed description are only exemplary and explanatory, and cannot limit this application. Detailed implementation manners

[0034] The following will describe the implementation manners of this application in more detail. Although the following examples show the implementation manners of this application, it should be understood that this application can be implemented in various forms and should not be limited by the implementation manners set forth herein. On the contrary, these implementation manners are provided to make this application more thorough and complete, and to fully convey the scope of this application to those skilled in the art.

[0035] Unless otherwise specified, the following experimental materials are all purchased from the market.

[0036] Example 1: Enzymatic hydrolysis - gradient pressing basic process

[0037] (1) Select raw materials

[0038] Select mature Sacha inchi fruits, remove dead branches and leaves, wash them, and perform shelling treatment to obtain Sacha inchi kernels;

[0039] (2) Crushing: Crush the Sacha inchi kernels in step (1), sieve them with a 10 - 60 mesh sieve, and dry them at 35°C until the moisture content is below 6% to obtain the crushed kernels;

[0040] (3) Enzymatic hydrolysis pretreatment: Mix the crushed kernels with water at a ratio of 1:4 (w / v, g / mL), first adjust the pH to 5.0 with 0.1 mol / L citric acid buffer, add a compound enzyme preparation (cellulase: pectinase: xylanase = 3:2:1), and the addition amount is 0.8% - 1.2% of the kernel mass. Enzymatically hydrolyze at 50°C with shaking for 1 h; then add lipase (the addition amount is 0.1% of the kernel mass) and continue enzymatic hydrolysis for 1.5 h, and the total enzymatic hydrolysis time is 2.5 h.

[0041] Among them, the cellulase: product number CTec3, lipase: product number TLIM (Novozymes China Biotechnology Co., Ltd.), pectinase: product number P2611 (Sigma - Aldrich (Shanghai) Trading Co., Ltd.), xylanase: product number XY (Genencor (China) Bio - Engineering Co., Ltd.).

[0042] (4) Ultrasonic-assisted cell wall disruption: After enzymatic hydrolysis, the material is treated with 40 kHz ultrasonic waves for 25 min at a power of 400 W. The ultrasonic treatment after enzymatic hydrolysis generates high-frequency mechanical vibrations and microjets through the cavitation effect, which can effectively break the cell wall structure remaining after enzymatic hydrolysis, significantly release the bound oil, and synchronously homogenize the system at low temperature (≤50 °C) during ultrasonic treatment (28 - 40 kHz, 20 - 30 min), reduce the viscosity and promote oil-water separation, while avoiding the degradation of heat-sensitive components. It is the core process link of this invention that combines high efficiency and quality assurance.

[0043] (5) Gradient low-temperature pressing:

[0044] The material after ultrasonic treatment in step (4) is subjected to the first-stage pressing: pressing at 53 °C / 18 MPa for 10 min, and the virgin oil is collected; then the second-stage pressing is carried out: pressing at 38 °C / 32 MPa until no oil oozes out; the virgin oil is obtained.

[0045] (6) The oil phases obtained in step (5) are combined and filtered through a 0.1 μm ceramic membrane to obtain Sacha inchi oil.

[0046] Example 2: Synergistic optimization of raw material pretreatment by compound enzyme addition amount and mechanical oscillation

[0047] Except for the following steps, the rest are the same as in Example 1.

[0048] (3) Enzymatic hydrolysis pretreatment: The crushed material is put into a continuous enzymatic hydrolysis reactor (with temperature control and oscillation module), and a compound enzyme preparation (the compound enzyme preparation in Example 1) is added at 0.9% of the raw material weight; the pH is adjusted to 4.8, and the temperature is raised to 47 °C.

[0049] The mechanical oscillation system is started (amplitude 6 μm, frequency 20 Hz), and enzymatic hydrolysis is continued for 2.2 hours.

[0050] (4) Ultrasonic-assisted cell wall disruption: The material after enzymatic hydrolysis is treated with 32 kHz ultrasonic waves for 30 min (power 350 W).

[0051] Example 3: Supercritical CO2 enhancement process

[0052] On the basis of Example 1, the residue after pressing in step (5) is subjected to supercritical CO2 extraction. The extraction process is as follows: pressure 28 MPa, temperature 40 °C, CO2 flow rate 28 kg / h, extraction time 1.8 h. The extracted oil is combined with the virgin oil obtained in step (5) of Example 1, and finally filtered uniformly. Step (6) of merging is carried out.

[0053] Efficiently extract the 4%-6% bound oil residues in the pressed residues through low-temperature and high-pressure CO2 fluid, which can improve the oil yield while maintaining an α-linolenic acid retention rate > 94% and a vitamin E content of 158 mg / 100 g. The supercritical technology avoids chemical solvent residues, and the extracted oil is combined with the virgin oil and then uniformly filtered through a ceramic membrane (0.1 μm) to ensure product purity. Although this step increases the processing time, it can extract more high-value oil per ton of raw materials, resulting in significant comprehensive benefits.

[0054] Comparative Example 1

[0055] Except for the following steps, the rest are the same as in Example 1.

[0056] The complex enzyme preparation in step (3) is: a mixture of cellulase and pectinase, with a ratio of 1:3 - 1:5. The pH is 5.0.

[0057] Comparative Example 2

[0058] Except for the following steps, the rest are the same as in Example 1.

[0059] Do not use ultrasonic-assisted cell wall breaking treatment.

[0060] Comparative Example 3: Traditional pressing method

[0061] (1) Raw material selection: Select mature Sacha inchi fruits, remove the shells to obtain kernels with a moisture content ≤ 8%.

[0062] (2) Raw material pretreatment: Spread the kernels on a baking tray and dry them with hot air at 60 ± 2°C for 6 hours until the moisture content ≤ 5%, then crush and pass through a 40-mesh sieve.

[0063] (3) Pressing: Press the product in step (2); the initial pressure is 10 MPa (for 5 min), and it is gradually increased to 35 MPa (maintained until the oil yield < 1% / min); the fruit oil is coarsely filtered through an 80-mesh stainless steel filter screen to obtain virgin oil.

[0064] (4) Filtration and refining: Primary filtration: Plate and frame filter press (filter cloth pore size 10 μm), keep the oil temperature at 50 - 55°C (to reduce viscosity).

[0065] Secondary fine filtration: Add 1.5% diatomaceous earth (w / w) as a filter aid and filter under a pressure of 0.3 MPa.

[0066] (5) Storage of refined oil: Store in a nitrogen-filled, sealed and light-proof manner (below 25°C).

[0067] Comparative Example 4: Solvent method

[0068] (1) Raw material pretreatment: Dry the Sacha inchi kernels at 60°C until the moisture ≤ 5%, then crush and pass through a 40-mesh sieve.

[0069] (2) Solvent extraction: Weigh the powder and place it in a Soxhlet extractor. Add n-hexane according to a solid-liquid ratio of 1:6 (w / v). Reflux and extract in a water bath at 75 °C for 4 hours, with the number of extraction cycles being 8 - 10 times.

[0070] (3) Solvent recovery: After filtering the extract through filter paper, concentrate and recover n-hexane using a rotary evaporator (50 °C, -0.09 MPa).

[0071] (4) Oil purification: Place the crude oil in a vacuum drying oven (60 °C, -0.1 MPa) to remove the solvent for 2 hours to obtain refined Sacha inchi oil.

[0072] Comparative Example 5: Conventional aqueous enzymatic method

[0073] (1) Raw material pretreatment: Mix Sacha inchi kernels with deionized water at a ratio of 1:3 (w / v), and grind them with a colloid mill to a particle size ≤ 50 μm to obtain a slurry.

[0074] (2) Enzymatic hydrolysis process: Adjust the pH of the slurry to 8.5 (for alkaline protease) and 5.0 (for cellulase), and add 1.5% and 1.0% enzyme amounts respectively. Hydrolyze at 50 °C for 3 hours, and stir for 5 minutes every 30 minutes during this period.

[0075] (3) Demulsification and separation: Inactivate the enzyme in the hydrolyzate at 90 °C for 10 minutes. After cooling, centrifuge at 4000×g for 20 minutes. Collect the upper oil phase, filter it through diatomaceous earth, and then perform pasteurization (72 °C / 15 s).

[0076] To illustrate the technical effects brought by the present invention, the amounts of Sacha inchi oil obtained in Example 1, Example 2, Example 3 and each comparative example were statistically analyzed, the oil yield of Sacha inchi oil was calculated, and the physical and chemical indexes, solvent residues, and process duration in the Sacha inchi oil were detected and statistically analyzed.

[0077]

[0078] In the formula: The dry basis mass of the raw material refers to the mass measured after drying.

[0079] Color: Determination standard: GB / T 22460 - 2008 "Determination of Lovibond color of animal and vegetable oils and fats"

[0080] Method: Weigh 2.0 g of the oil sample, filter it through a 0.22 μm filter membrane to remove impurities; turn on the light source of the colorimeter and preheat for 10 minutes. Fill the colorimetric cell with pure reference oil (colorless), and adjust the instrument to zero (Y = 0 / R = 0). Inject the oil sample to be measured into the colorimetric cell (avoiding air bubbles), and wipe the outer wall clean. Adjust the yellow (Y) and red (R) color scale plates in sequence until the color of the sample matches the standard color scale. Record the Y / R value at the time of matching. Repeat the determination: Measure in parallel 3 times and take the average value.

[0081] Acid value: Determination standard: GB 5009.229-2016 "Determination of Acid Value in Foods"

[0082] Method: Weigh 3.0 ± 0.1 g of the oil sample and dissolve it in 50 mL of a mixed solution of ether - isopropanol (1:1); titrate with 0.1 mol / L KOH standard solution until it turns pink, and shake well (phenolphthalein indicator, does not fade in 15 seconds). Conduct a blank test simultaneously.

[0083] Calculation formula:

[0084]

[0085] In the formula: X AV — Acid value, unit is milligram per gram (mg / g);

[0086] V — Volume of the standard titration solution consumed in the determination of the sample, unit is milliliter (mL);

[0087] V0 — Volume of the standard titration solution consumed in the corresponding blank determination, unit is milliliter (mL);

[0088] c — Molar concentration of the standard titration solution, unit is mole per liter (mol / L);

[0089] 56.1 — Molar mass of potassium hydroxide, unit is gram per mole (g / mol);

[0090] m — Sampling amount of the oil sample, unit is gram (g).

[0091] Peroxide value: Determination standard: GB 5009.227-2016 "Determination of Peroxide Value in Foods"

[0092] Method: Weigh 2.0 g of the oil sample, add 50 mL of a mixed solution of chloroform - glacial acetic acid, and gently shake to completely dissolve the sample. Accurately add 1.00 mL of saturated potassium iodide solution, tighten the bottle cap, and gently shake for 0.5 min, then place it in the dark for 3 min; titrate with 0.01 mol / L Na2S2O3 until it becomes colorless. Conduct a blank test simultaneously.

[0093] Calculation formula:

[0094]

[0095] In the formula: X — Peroxide value, unit is millimole per kilogram (mmol / kg);

[0096] V — Volume of the sodium thiosulfate standard solution consumed by the sample, unit is milliliter (mL);

[0097] V0—the volume of the sodium thiosulfate standard solution consumed in the blank test, unit: milliliter (mL);

[0098] C—the concentration of the sodium thiosulfate standard solution, unit: mole per liter (mol / L);

[0099] m—the mass of the sample, unit: gram (g);

[0100] Contents of α-linolenic acid, linoleic acid, and total unsaturated fatty acids:

[0101] Determination standard: GB 5009.168-2016 Determination of Fatty Acids in Foods

[0102] Method: Oil methylation: Take 50 mg of oil sample + 2 mL of 0.5 mol / L NaOH-methanol (water bath at 70 °C for 5 min) → add 3 mL of BF3-methanol (14%) → derivatization; Analysis conditions: Chromatographic column: CP-Sil 88 (100 m × 0.25 mm × 0.2 μm); Program temperature rise: 150 °C (2 min) → 4 °C / min → 240 °C (10 min); FID detector (260 °C)

[0103] Calculation formula:

[0104] In the formula: Ai: the area of the target peak

[0105] Fi: relative correction factor (ALA = 1.03, linoleic acid = 1.02)

[0106] Vitamin E: Refer to GB 5009.82—2016 Determination of Vitamins A, D, and E in Foods

[0107] Method: Weigh 0.5 g of oil sample and add 10 mg of BHT (antioxidant); dissolve with the mobile phase and make up the volume to 25 mL, filter through a 0.22 μm filter membrane and directly inject into the liquid chromatograph. Liquid chromatographic column conditions: Amide column (150 × 3.0 mm, 1.7 μm); Mobile phase: n-hexane-tert-butyl methyl ether mixture (90:10); Flow rate: 0.8 mL / min; Detection: Fluorescence (Ex 294 nm / Em 328 nm); Injection volume: 10 μL, calculated by the external standard method.

[0108] Calculation formula:

[0109] In the formula:

[0110] X—the content of α-tocopherol, β-tocopherol, γ-tocopherol, or δ-tocopherol in the sample, unit: milligram per hundred grams (mg / 100 g);

[0111] ρ—the concentration of α-tocopherol, β-tocopherol, γ-tocopherol or δ-tocopherol in the sample calculated according to the standard curve, in micrograms per milliliter (μg / mL);

[0112] V—the volume of constant volume, in milliliters (mL);

[0113] f—the conversion factor (f = 0.001);

[0114] 100—the conversion coefficient for calculating the sample weight per 100 grams;

[0115] m—the weighed amount of the sample, in grams (g).

[0116] Table 1. Oil yield of each example and comparative example

[0117] Group Oil yield rate (%) Example 1 45.8 Example 2 48.8 Example 3 53.1 Comparative Example 1 38.6 Comparative Example 2 42.1 Comparative Example 3 (Traditional pressing method) 31.2 Comparative Example 4 (Solvent method) 38.5 Comparative Example 5 (Conventional aqueous enzymatic method) 42.6

[0118] Table 2. Physicochemical property indexes of Sacha inchi oil

[0119]

[0120] It can be seen from the above data that:

[0121] 1. Comparative analysis of oil yield

[0122] The oil yields of Examples 1-3 of the present invention (45.8%-53.1%) are significantly higher than those of the traditional pressing method (31.2%) and the aqueous enzymatic method (42.6%). Supercritical assistance (Example 3) enables the total oil yield to reach as high as 53.1%.

[0123] Defects of traditional processes: The pressing method has the lowest oil yield (31.2%) due to incomplete cell wall breaking, and the solvent method has potential safety hazards (n-hexane residue 12.3 ppm).

[0124] 2. Color: Low-temperature pressing + membrane filtration in the examples makes the color of the oil stronger, which is better than that of traditional pressing; in the comparative example, high-temperature pressing leads to an intensified Maillard reaction and darker oil color; the solvent-extracted oil shows a dark yellow color due to the loss of carotenoids during desolventization and refining.

[0125] 3. Acid value: Enzymatic pretreatment in the examples destroys the activity of lipoxygenase, and the acid value ≤ 0.8 mg KOH / g; a low acid value indicates a low degree of oil hydrolysis and an extended shelf life.

[0126] 4. α-linolenic acid: The α-linolenic acid content in Examples 1-3 is greater than 42%, indicating that the process causes extremely low damage to high-activity components; while in Comparative Example 3 (traditional pressing method), α-linolenic acid is lost due to high temperature.

[0127] 5. Retention of the activity of thermosensitive components: The retention of thermosensitive components in the examples is relatively high, while high-temperature pressing and solvent deodorization in traditional processes lead to the degradation of thermosensitive components.

[0128] 6. Production efficiency: The shortest process time in the examples is 4 h, while it is 8 h in Comparative Example 4.

[0129] 7. Safety: There is no solvent residue in the examples, while the n-hexane residue in Comparative Example 4 is 12.3 ppm.

[0130] The embodiments of the present application have been described above. The above description is exemplary and not exhaustive, and is also not limited to the disclosed embodiments. Many modifications and variations are obvious to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments. The choice of terms used herein is intended to best explain the principles of the embodiments, practical applications, or improvements to technologies in the market, or to enable other ordinary skill in the art to understand the embodiments disclosed herein.

Claims

1. A preparation method of Sacha Inchi oil, characterized in that, The method comprises the following steps: 1) The seeds of Physic nut are successively crushed, sieved and dried to obtain crushed Physic nut seeds; 2) The crushed Physic nut seeds obtained in 1) are mixed with water, and a compound enzyme preparation is added. It is oscillated at pH 4.5 - 5.5 and 45 - 50 °C for 1 h, and then lipase is added and oscillated for 1 - 2 h; the enzymolysis product is obtained; The compound enzyme preparation is cellulase:pectinase:xylanase, and the mass ratio is 3:2:1; 3) The enzymolysis product in 2) is subjected to ultrasonic treatment; the ultrasonically treated material is obtained; 4) The material in 3) is subjected to gradient low-temperature pressing to obtain crude oil. The gradient low-temperature pressing is divided into a first stage and a second stage; The conditions of the first stage are pre-pressing at 50 - 55 °C and a pressure of 15 - 20 MPa for 10 min; The conditions of the second stage are final pressing at 35 - 40 °C and the pressure is increased to 30 - 35 MPa; 5) The crude oil is filtered to obtain a filtrate, which is Physic nut oil.

2. The preparation method according to claim 1, wherein The moisture content of the crushed Physic nut seeds is below 6%.

3. The preparation method according to claim 1, characterized in that, The amplitude of the oscillation is 5 - 10 μm and the frequency is 15 - 20 Hz.

4. The preparation method according to claim 1, characterized in that The frequency of the ultrasonic wave in 3) is 28 - 40 kHz and the time is 20 - 30 min.

5. The preparation method according to claim 1, characterized in that, The addition amount of the compound enzyme preparation in 2) is 0.8% - 1.2% of the mass of the crushed Physic nut seeds, and the addition amount of lipase is 0.1% of the mass of the crushed Physic nut seeds.

6. The preparation method according to claim 1, wherein The filtration in 5) is carried out with a 0.1 μm ceramic membrane at 25 - 30 °C.

7. An extraction method of Sacha Inchi oil, characterized in that, The extraction method comprises: Taking the residue after pressing in steps 1) - 4) of the method as claimed in claim 1, the residue is subjected to supercritical CO2 extraction to obtain an oil phase, which is combined into the crude oil in 4), and then filtered to obtain a filtrate, which is Physic nut oil.

8. The extraction method according to claim 7, wherein The conditions of the supercritical CO2 extraction process are a pressure of 25 - 30 MPa, a temperature of 40 ± 1 °C, a CO2 flow rate of 25 kg / h, and an extraction time of 1.5 h.

9. The application of Physic nut oil obtained by the preparation method as claimed in any one of claims 1 - 6 or the extraction method as claimed in any one of claims 7 - 8 in functional foods.

10. The application of Physic nut oil obtained by the method as claimed in any one of claims 1 - 6 or the extraction method as claimed in any one of claims 7 - 8 in cosmetics.

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