Floor camellia seed processing method based on synergistic squeezing of shells and kernels

Abstract

The invention relates to the technical field of edible oil and fat processing, in particular to a ground camellia seed processing method based on shell and kernel synergistic squeezing, which comprises the following steps: cleaning with shells, centrifugally shelling, performing color sorting on camellia seed kernels, mixing shells and kernels, steaming and curing, tabletting and baking, and squeezing and refining. The method provided by the invention is a method for improving the safety and flavor quality of the tea oil through pretreatment of cleaning with shells, centrifugal husking and tea seed kernel color sorting and a shell and kernel synergistic squeezing technology, and has outstanding substantive significance.

Description

Technical Field

[0001] The invention relates to the technical field of edible oil processing, and in particular to a method for processing camellia seeds based on coordinated squeezing of shells and kernels. Background Art

[0002] Camellia oil contains over 90% unsaturated fatty acids (80-83% oleic acid, 7-13% linoleic acid), is rich in vitamins A, B, D, E, and linolenic acid, and is free of erucic acid, cholesterol, and aflatoxin. Its nutritional value has earned it the Food and Agriculture Organization's top recommendation as a health-promoting edible oil. Camellia seeds (also known as camellia seeds) are collected after naturally ripening and falling off, and can be used to make camellia oil. However, using camellia seeds as a processing raw material often presents the following technical challenges due to their natural detachment from the ground:

[0003] 1. Risk of impurities and mold: Traditional processes involve direct pressing or washing after shelling, which results in the absorption of dirt (particle size ≤ 100 μm) by shell debris. This can lead to a 10%-15% missed detection rate for moldy kernels, resulting in elevated acid values ​​(≥ 2.5 mg / g) and mycotoxin contamination.

[0004] 2. Process connection defects: The existing technology (such as CN202510545386.2) does not set up a color sorting process after shelling, resulting in delayed mold detection, affecting the stability of subsequent ripening and pressing;

[0005] 3. Low pressing efficiency: Tea seed kernels contain about 15% tea saponin, which forms a viscous substance when it comes into contact with water during the pressing process, causing the oil circuit to be blocked and reducing the oil yield.

[0006] These technical issues are not addressed by existing technologies, nor are there publicly available solutions. In fact, these issues with camellia oil produced from ground seeds seriously impact the quality of finished products. Furthermore, with consumer demand for camellia oil growing year by year, producing high-quality camellia oil and achieving a comprehensive upgrade in safety, flavor, and nutrition is of great significance.

[0007] Therefore, it is necessary to propose a camellia seed processing method based on the coordinated pressing of the shell and kernel. Summary of the Invention

[0008] In view of the above, it is necessary to provide a camellia seed processing method based on shell-kernel co-pressing, which can improve the safety and flavor quality of tea oil through the "shell cleaning-centrifugal shelling-tea seed kernel color sorting" pretreatment and shell-kernel co-pressing technology.

[0009] In order to achieve the above object, the technical solution adopted by the present invention is:

[0010] A method for processing camellia seeds based on synergistic squeezing of shells and kernels, the method comprising the following steps:

[0011] (1) Shell cleaning: Use dual-frequency ultrasonic cleaning, water wave vibration cleaning, gravity drop and thermal air separation in sequence to make the content of shelled moldy seeds ≤1.0%;

[0012] (2) Centrifugal shelling: A vertical centrifugal machine is used to crack and shell the tea seeds. The shelling machine's air selection channel separates the tea seed kernels from the tea seed shells. By controlling the air volume, the tea seed kernels retain part of the tea seed shells.

[0013] (3) Tea seed kernel color sorting: Use a dual-spectrum color sorter to remove moldy tea seed kernels, and the residual rate of moldy kernels is ≤0.05%;

[0014] (4) Steaming and maturation: After color sorting, the tea seed kernels are sent to the steaming tower and steamed at 105-115℃ for 3-5 minutes;

[0015] (5) Tableting: The steamed tea seed kernels are sent to a flattening machine and pressed into 0.8-1.2 mm thin slices to obtain tea kernel slices;

[0016] (6) Tea kernel slice processing: send the tea kernel slices to the hot air oven, control the oven temperature at 125-135℃, and tumble bake the tea kernel slices to activate the production of aroma precursors;

[0017] (7) Pressing and refining: The processed flakes are pressed and the crude oil is condensed and then cold-extracted to recover the aroma, and then the aroma is added back to obtain the finished oil.

[0018] In the present invention, further, in step (1), the dual-frequency ultrasonic cleaning is performed at 28kHz for 2-3 minutes and then switched to 40kHz for 1-2 minutes; the water flow rate of the water wave vibration cleaning is 0.8-1.2m / s and the time is 6-8min; the gravity drop height is 1-1.5m, and the wind speed of the thermal air separation is 6-10m / s.

[0019] In the present invention, further, the dual-spectrum color sorting in step (3) adopts RGB+near-infrared dual-mode recognition, and the absorbance of the near-infrared spectrum at 1740nm is ≥0.3 as the mold judgment threshold; the CCD imaging frequency of the dual-spectrum color sorter is ≥8000 frames / second.

[0020] In the present invention, further, in the step (2), in the tea seed kernels with tea seed husks retained, the mass ratio of tea seed kernels to tea seed husks is 90:10.

[0021] In the present invention, further, the pressing treatment in step (7) is carried out under the conditions of 120-130° C. and 20-25 MPa.

[0022] In the present invention, further, the step (7) of condensing and recovering the aroma comprises: the squeezing waste gas is subjected to a three-stage gradient condensation system to recover the aroma substances, with the condensation temperature gradient being -5±1°C → -15±1°C → -25±1°C, to obtain a condensate. The three-stage gradient condensation adopts a stainless steel coil condenser.

[0023] In the present invention, further, the step (7) low-temperature cold extraction is: centrifuging the pressed crude oil at ≤40°C and 8000-10000rpm to remove impurities to a residual amount of ≤0.1% to obtain refined oil.

[0024] In the present invention, further, the step (7) of adding flavor back is to add condensate to the refined oil, and the added amount is 0.05%-0.3% of the weight of the refined oil.

[0025] The present invention has at least the following beneficial effects:

[0026] This invention proposes a method for processing camellia seeds based on co-pressing of shells and kernels. Through the innovative process chain of "shell cleaning - color sorting after shelling - co-pressing of shells and kernels - low-temperature cold extraction", it achieves multiple breakthroughs in camellia oil processing, including blocking the source of safety risks, fully preserving nutritional activity, and significantly improving pressing efficiency.

[0027] First, it blocks the source of safety risks, specifically: (1) Completely eliminate mold contamination: Through the sequential pretreatment of "cleaning in shell → dual-spectrum color sorting after shelling", moldy kernels hidden by the shell are accurately removed, preventing the introduction of aflatoxins and rancidity factors from the source. (2) Effectively inhibit the formation of harmful substances: Medium-temperature pressing and the use of tea shell drainage brackets reduce pressing viscosity, avoid local high-temperature coking, and significantly inhibit the formation of carcinogens such as benzopyrene.

[0028] Secondly, it achieves a synergistic improvement in nutrition and flavor, as shown in the following: (1) High-efficiency retention of active ingredients: Using a low-temperature cold extraction process instead of chemical refining, it avoids the damage of high temperature and strong acid and alkali to active ingredients such as sterols and vitamin E, achieving nearly complete natural nutrition retention. (2) Targeted enrichment of flavor substances: The three-level gradient condensation and aroma recovery process accurately captures volatile flavor substances (such as trans-2-nonenal), which are then added back to form a rich and natural nutty flavor, breaking through the bottleneck of traditional processes where the flavor is bland or mixed.

[0029] Third, a breakthrough optimization of pressing efficiency was achieved, as shown in the following: (1) The problem of oil channel blockage was solved: During the 90:10 kernel and shell synergistic pressing, tea seed shell fibers formed a natural drainage channel, effectively absorbing tea saponin viscous substances, avoiding oil channel blockage and significantly improving oil extraction efficiency. (2) Energy consumption and residual oil rate were both reduced: The drainage channel reduced pressing resistance, shortened high-pressure pressing time and energy consumption, and simultaneously reduced the residual oil rate of tea bran, achieving efficient resource utilization.

[0030] Not only that, this application also achieves a new upgrade in process cleanliness, with zero dependence on chemical additives, and uses physical impurity control (shell cleaning + centrifugal cold extraction) instead of chemical refining, eliminating the risk of solvent residues and complying with the trend of clean production.

[0031] In summary, this invention, through its comprehensive innovation process of "source mold removal, coordinated shell and kernel drainage, and low-temperature aroma preservation," eliminates the risk of toxins and carcinogens at the source, preserves natural active ingredients, and enriches aroma-producing substances, achieving both superior flavor and nutritional benefits. It also addresses the problem of tea saponin blockage, increases oil yield, and reduces energy consumption. Furthermore, it replaces chemical refining with physical methods, promoting greener oil processing. Overall, this invention achieves a four-pronged quality improvement in camellia oil: safety, flavor, nutrition, and efficiency. DETAILED DESCRIPTION

[0032] All features disclosed in this specification, or all steps in the disclosed methods or processes, except mutually exclusive features and / or steps, can be combined in any manner.

[0033] Any feature disclosed in this specification (including any accompanying claims and abstract), unless otherwise stated, is merely an example of a series of equivalent or similar features.

[0034] Example 1:

[0035] This embodiment provides a method for processing camellia seeds based on co-pressing of shells and kernels, the method comprising the following steps:

[0036] (1) Shell cleaning: Take the fallen camellia seeds from Dongbafeng area of ​​Guangxi and perform the following impurity removal operations in sequence:

[0037] ① Dual-frequency ultrasonic cleaning: 28kHz cleaning for 2.5 minutes (removing impurities with a particle size greater than 500μm), then switch to 40kHz cleaning for 1.5 minutes (removing dust ≤100μm);

[0038] ② Water wave vibration cleaning: the cleaning water flow rate is 1.0m / s, the frequency is 45Hz, and the time is 7min;

[0039] ③ Gravity drop: drop height 1.2m (stone removal rate 100%);

[0040] ④ Thermal air separation: wind speed is 8m / s (broken leaves / empty shell removal rate is 96%);

[0041] Results: The content of shelled and rotten seeds was reduced to 0.9% (≤1.0%);

[0042] (2) Centrifugal shelling: The tea seeds are shelled by vertical centrifugal separation. The tea seed kernels and tea seed shells are separated by air separation in the shelling machine. By controlling the air volume, the tea seed kernels retain part of the tea seed shells. In the tea seed kernels that retain the tea seed shells, the mass ratio of tea seed kernels to tea seed shells is 90:10.

[0043] (3) Tea seed kernel color sorting: Moldy tea seed kernels were removed by a dual-spectrum color sorter (Taihe). The dual-spectrum color sorting adopted RGB+NIR dual-mode recognition. The absorbance of the near-infrared spectrum at 1740nm was ≥0.3, which was the threshold for moldy determination. The CCD imaging frequency of the dual-spectrum color sorter was ≥8000 frames / second. Result: The residual rate of moldy kernels was ≤0.05%;

[0044] (4) Steaming and maturation: After color sorting, the tea seed kernels are sent to the steaming tower, steamed at 110℃ for 4 minutes;

[0045] (5) Tableting: The steamed tea seed kernels are sent to a flattening machine and pressed into 1.0 mm thin slices to obtain tea kernel slices;

[0046] (6) Tea kernel slice processing: send the tea kernel slices to a hot air oven, control the oven temperature at 130°C, and tumble bake the tea kernel slices to activate the production of aroma precursors;

[0047] (7) Pressing and refining: The treated flakes are pressed at 125°C and 22 MPa to obtain crude oil for later use;

[0048] (8) Condensation and aroma recovery: The compressed waste gas is recycled through a three-stage gradient condensation system to recover the condensate of the aromatic substances. The three-stage gradient condensation system includes:

[0049] First-stage condensation: -5℃ captures low-boiling-point aldehydes with boiling point ≤130℃; second-stage condensation: -15℃ captures medium-boiling-point substances with boiling point 130-180℃; third-stage condensation: -25℃ captures high-boiling-point substances with boiling point ≥180℃;

[0050] (9) Low temperature cold extraction: The crude oil is centrifuged at ≤40°C and 9000 rpm to remove impurities until the residual amount is ≤0.1% to obtain refined oil. The phospholipid content of the refined oil is ≤0.08% and the wax residue is ≤0.02%;

[0051] (10) Fragrance recovery: Add condensate to the refined oil in an amount of 0.2% of the weight of the refined oil to obtain the finished oil.

[0052] Example 2:

[0053] This embodiment provides a method for processing camellia seeds based on co-pressing of shells and kernels, the method comprising the following steps:

[0054] (1) Shell cleaning: Take the fallen camellia seeds from Dongbafeng area of ​​Guangxi and perform the following impurity removal operations in sequence:

[0055] ① Dual-frequency ultrasonic cleaning: 28kHz cleaning for 2 minutes (removing impurities with a particle size greater than 500μm), then switch to 40kHz cleaning for 1 minute (removing dust ≤ 100μm);

[0056] ② Water wave vibration cleaning: the cleaning water flow rate is 0.8m / s, the frequency is 40Hz, and the time is 6min;

[0057] ③ Gravity drop: drop height 1m (stone removal rate 100%);

[0058] ④ Thermal air separation: wind speed is 6m / s (broken leaves / empty shell removal rate is 96%);

[0059] Results: The content of shelled and rotten seeds was reduced to 0.9% (≤1.0%);

[0060] (2) Centrifugal shelling: The tea seeds are shelled by vertical centrifugal separation. The tea seed kernels and tea seed shells are separated by air separation in the shelling machine. By controlling the air volume, the tea seed kernels retain part of the tea seed shells. In the tea seed kernels that retain the tea seed shells, the mass ratio of tea seed kernels to tea seed shells is 90:10.

[0061] (3) Tea seed kernel color sorting: Moldy tea seed kernels were removed by a dual-spectrum color sorter (Taihe). The dual-spectrum color sorting adopted RGB+NIR dual-mode recognition. The absorbance of the near-infrared spectrum at 1740nm was ≥0.3, which was the threshold for moldy determination. The CCD imaging frequency of the dual-spectrum color sorter was ≥8000 frames / second. Result: The residual rate of moldy kernels was ≤0.05%;

[0062] (4) Steaming and maturation: After color sorting, the tea seed kernels are sent to the steaming tower, where steam is introduced and steamed at 105°C for 3 minutes.

[0063] (5) Tableting: The steamed tea seed kernels are sent to a flattening machine and pressed into 0.8 mm thin slices to obtain tea kernel slices;

[0064] (6) Tea kernel slice processing: send the tea kernel slices to a hot air oven, control the oven temperature at 125°C, and tumble bake the tea kernel slices to activate the production of aroma precursors;

[0065] (7) Pressing and refining: The treated flakes are pressed at 120°C and 20 MPa to obtain crude oil for later use;

[0066] (8) Condensation and aroma recovery: The compressed waste gas is recycled through a three-stage gradient condensation system to recover the condensate of the aromatic substances. The three-stage gradient condensation system includes:

[0067] First-stage condensation: -4℃ captures low-boiling-point aldehydes with boiling point ≤130℃; second-stage condensation: -14℃ captures medium-boiling-point substances with boiling point 130-180℃; third-stage condensation: -24℃ captures high-boiling-point substances with boiling point ≥180℃;

[0068] (9) Low temperature cold extraction: The crude oil is centrifuged at ≤40°C and 8000-10000 rpm to remove impurities until the residual amount is ≤0.1% to obtain refined oil. The phospholipid content of the refined oil is ≤0.08% and the wax residue is ≤0.02%;

[0069] (10) Fragrance recovery: Add condensate to the refined oil in an amount of 0.05% of the weight of the refined oil to obtain the finished oil.

[0070] Example 3:

[0071] This embodiment provides a method for processing camellia seeds based on co-pressing of shells and kernels, the method comprising the following steps:

[0072] (1) Shell cleaning: Take the fallen camellia seeds from Dongbafeng area of ​​Guangxi and perform the following impurity removal operations in sequence:

[0073] ① Dual-frequency ultrasonic cleaning: 28kHz cleaning for 3 minutes (removing impurities with a particle size greater than 500μm), then switch to 40kHz cleaning for 2 minutes (removing dust ≤100μm);

[0074] ② Water wave vibration cleaning: the cleaning water flow speed is 1.2m / s, the frequency is 50Hz, and the time is 8min;

[0075] ③ Gravity drop: drop height 1.5m (stone removal rate 100%);

[0076] ④ Thermal air separation: wind speed is 10m / s (broken leaves / empty shell removal rate is 96%);

[0077] Results: The content of shelled and rotten seeds was reduced to 0.9% (≤1.0%);

[0078] (2) Centrifugal shelling: The tea seeds are shelled by vertical centrifugal separation. The tea seed kernels and tea seed shells are separated by air separation in the shelling machine. By controlling the air volume, the tea seed kernels retain part of the tea seed shells. In the tea seed kernels that retain the tea seed shells, the mass ratio of tea seed kernels to tea seed shells is 90:10.

[0079] (3) Tea seed kernel color sorting: Moldy tea seed kernels were removed by a dual-spectrum color sorter (Taihe). The dual-spectrum color sorting adopted RGB+NIR dual-mode recognition. The absorbance of the near-infrared spectrum at 1740nm was ≥0.3, which was the threshold for moldy determination. The CCD imaging frequency of the dual-spectrum color sorter was ≥8000 frames / second. Result: The residual rate of moldy kernels was ≤0.05%;

[0080] (4) Steaming and maturation: After color sorting, the tea seed kernels are sent to the steaming tower, steamed at 115℃ for 5 minutes;

[0081] (5) Tableting: The steamed tea seed kernels are sent to a flattening machine and pressed into 1.2 mm thin slices to obtain tea kernel slices;

[0082] (6) Tea kernel slice processing: send the tea kernel slices to a hot air oven, control the oven temperature at 135°C, and tumble bake the tea kernel slices to activate the production of aroma precursors;

[0083] (7) Pressing and refining: The treated flakes are pressed at 130°C and 25 MPa to obtain crude oil for later use;

[0084] (8) Condensation and aroma recovery: The compressed waste gas is recycled through a three-stage gradient condensation system to recover the condensate of the aromatic substances. The three-stage gradient condensation system includes:

[0085] First-stage condensation: -6℃ to capture low-boiling-point aldehydes with boiling point ≤130℃; second-stage condensation: -16℃ to capture medium-boiling-point substances with boiling point 130-180℃; third-stage condensation: -26℃ to capture high-boiling-point substances with boiling point ≥180℃;

[0086] (9) Low temperature cold extraction: The crude oil is centrifuged at ≤40°C and 10,000 rpm to remove impurities until the residual amount is ≤0.1% to obtain refined oil. The phospholipid content of the refined oil is ≤0.08% and the wax residue is ≤0.02%;

[0087] (10) Fragrance recovery: Add condensate to the refined oil in an amount of 0.3% of the weight of the refined oil to obtain the finished oil.

[0088] Test data:

[0089] Test 1:

[0090] The applicant set up multiple groups for comparative testing to verify the unexpected effect of the core innovation of this application (shell cleaning + color sorting after shelling + shell and kernel co-pressing). First, the grouping situation is shown in Table 1:

[0091] Table 1 Grouping

[0092] Group Process characteristics Key parameters Example 1 This application's complete process (shell cleaning + color sorting + kernel-shell 90:10) Oil yield 29.8% Comparative Example 1 Pressing in shell (no cleaning or shelling) The residual rate of moldy seeds is 6.8% Comparative Example 2 Cleaning after shelling + pure kernel pressing (without shell) Tea saponin is sticky and blocked, and the pressing pressure increases by 30% Comparative Example 3 Shell cleaning + color sorting after shelling + pure kernel pressing (without shell) Pressing time extended by 25% Comparative Example 4 Shell cleaning + color sorting after shelling + kernel and shell 95:5 Insufficient shell ratio and insufficient discharge

[0093] Note: Except for the differences highlighted in the table, other methods are the same as Example 1.

[0094] Comparing the squeezing effects of the above groups, the results are shown in Table 2:

[0095] Table 2 Comparison of squeezing effects among groups

[0096] Group Oil yield Pressing time Peak pressing pressure Tea bran residual oil rate Example 1 29.8% 42min 24MPa 5.2% Comparative Example 1 25.1% 50min 28MPa 12.7% Comparative Example 2 26.3% 55min 35MPa 9.8% Comparative Example 3 27.5% 53min 26MPa 7.5% Comparative Example 4 28.1% 45min 25MPa 6.3%

[0097] According to the test results, when the shell-kernel ratio is 90:10 (Example 1), the oil yield is the highest (18.7% higher than the traditional process). This is because the tea shell forms a "drainage scaffold", which relieves the sticky blockage of tea saponins, thereby increasing the oil yield; while the pure kernel pressing (Comparative Example 2) causes the pressure to rise sharply by 35MPa due to the blockage of tea saponins, and the residual oil rate is as high as 9.8%.

[0098] Test 2:

[0099] The applicant found that adding tea shells during the process of extracting oil from tea kernels can increase the oil yield. To this end, the applicant further optimized and verified the ratio of shells to kernels. The results are shown in Table 3:

[0100] Table 3 Optimization verification of kernel-shell ratio

[0101] Kernel-shell mass ratio Oil yield Tea bran residual oil rate 100:0 (Pure Benevolence) 26.3% 9.8% 95:5 28.1% 6.3% 90:10 29.8% 5.2% 70:30 28.9% 5.8% 60:40 27.5% 7.1%

[0102] The results in Table 3 show that too little tea husk leads to insufficient drainage and a high residual oil rate; too much tea husk leads to insufficient compression space and a low oil yield. A 90:10 ratio yields the lowest residual oil rate (5.2%), a 47.9% reduction compared to pure kernel extraction. This suggests that while traditional processes consider tea husks to be impurities requiring complete removal, the present invention finds that using 10% tea husk as a "drainage scaffold" solves the problem of tea saponin stickiness and blockage (reducing viscosity by 16%), increasing oil yield to 29.8%.

[0103] Test 3:

[0104] The applicant further compared the recovery rate of trans-2-nonenal under various treatments. The traditional high-temperature pressing process is as follows: the tea seeds are not shelled, but are roasted at high temperature (150°C) and then pressed, and then chemically refined (deacidification, decolorization, and deodorization) to obtain the finished oil; the pure kernel pressing process is the same as Example 1 except that the tea shells are removed. The comparative test results are as follows:

[0105] Table 4 Comparison of recovery rates of trans-2-nonenal in each group

[0106] Group Recovery rate of trans-2-nonenal Example 1 (90:10 shell to kernel ratio) 91.8% Pure kernel pressing (without shell) 78.1% Traditional high temperature pressing (150℃) 42.4%

[0107] The test results show that the shell-kernel mixture reduces the pressing viscosity (42mPa·s vs 58mPa·s for pure kernels), making it easier for volatile aromas to escape; and the three-stage gradient condensation specifically captures substances with different boiling points (for example, trans-2-nonenal has a boiling point of 185°C and needs to be condensed at -15°C); the synergistic effect increases the key aroma recovery rate to 91.8% (the traditional process is only ≤50%).

[0108] Test 4:

[0109] This test case tested the breakthrough achieved by low-temperature cold extraction in nutrient retention. Current methods for removing impurities from crude oil include alkali refining (chemical refining) and high-temperature deodorization. This test case compared the effectiveness of the proposed method with existing methods. The core steps of traditional alkali refining are: degumming: adding water or phosphoric acid to cause the phospholipids to absorb water and flocculate, followed by centrifugation; alkali refining and deacidification: adding sodium hydroxide solution to neutralize free fatty acids and produce soap stock (which requires subsequent separation); washing: hot water washing to remove residual soap stock and alkali solution; and dehydration: vacuum drying to remove moisture. The core processes of high-temperature deodorization include: preheating: raising the oil temperature to 100–150°C; high-temperature distillation: introducing steam at 230–260°C under high vacuum (≤3 mbar) to volatilize odorous components; and cooling: rapidly cooling the oil to below 60°C after deodorization to prevent oxidation.

[0110] Comparing the low temperature cold extraction process of the present invention, the results are shown in Table 5:

[0111] Table 5 Comparison of nutrient retention

[0112] Refining process Treatment Sterol retention rate Vitamin E loss rate Security Low temperature cold extraction (≤40℃) ≤40℃ centrifugal removal (physical method) 98.8% ≤5% Zero chemical additives Traditional alkali refining Strong alkali neutralization + water washing 82% 35% Soapstock residue risk High temperature deodorization Steam distillation at 230–260°C 75% 60% Trans fatty acid production

[0113] It can be seen that traditional processes rely on chemical / high-temperature means, sacrificing nutrition and safety. The low-temperature cold extraction (≤40°C) in this application can remove impurities (phospholipids ≤0.08%) while retaining a sterol rate of 98.8% (the national standard requires ≥80%), achieving clean and efficient impurity removal while solving the high-temperature damage problem of traditional refining processes.

[0114] Test 5:

[0115] This experiment further conducted comparative tests on safety and nutritional indicators. The traditional process involved roasting tea seeds at high temperature (150°C) without shelling them, pressing them, and then chemically refining them (deacidification, decolorization, and deodorization) to obtain the finished oil. The comparative results are shown in Table 6:

[0116] Table 6 Comparison of safety and nutritional indicators

[0117] Test items Example 1 National standard limit Traditional crafts Acid value (mg KOH / g) 1.8 ≤3.0 3.5 <![CDATA[Aflatoxin B1 (μg / kg)]]> Not detected ≤2.0 3.8 Phospholipid content (%) 0.07 ≤0.2 0.21 Sterol retention rate (%) 98.8 ≥80 82 Oil yield 29.8% - 25.1%

[0118] Comparing the test results in Table 6, the proposed method of in-shell cleaning and post-shell color sorting resulted in no detectable toxins. Combined with low-temperature extraction (≤40°C), the resulting sterol retention rate reached 98.8%. This demonstrates that the resulting finished oil far surpasses the quality of conventional processes.

[0119] The above-described embodiments merely illustrate several embodiments of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that a person skilled in the art would be able to make various modifications and improvements without departing from the spirit of the present invention, all of which fall within the scope of protection of the present invention. Therefore, the scope of protection of the present invention shall be determined by the appended claims.

Claims

1. A method for processing camellia seeds based on collaborative squeezing of shell and kernel, characterized in that: The method comprises the following steps: (1) Shell cleaning: Use dual-frequency ultrasonic cleaning, water wave vibration cleaning, gravity drop and thermal air separation in sequence to make the content of shelled moldy seeds ≤1.0%; (2) Centrifugal shelling: A vertical centrifugal machine is used to crack and shell the tea seeds. The shelling machine's air selection channel separates the tea seed kernels from the tea seed shells. By controlling the air volume, the tea seed kernels retain part of the tea seed shells. (3) Tea seed kernel color sorting: Use a dual-spectrum color sorter to remove moldy tea seed kernels, and the residual rate of moldy kernels is ≤0.05%; (4) Steaming and maturation: After color sorting, the tea seed kernels are sent to the steaming tower and steamed at 105-115℃ for 3-5 minutes; (5) Tableting: The steamed tea seed kernels are sent to a flattening machine and pressed into 0.8-1.2 mm thin slices to obtain tea kernel slices; (6) Tea kernel slice processing: send the tea kernel slices to the hot air oven, control the oven temperature at 125-135℃, and tumble bake the tea kernel slices; (7) Pressing and refining: The processed tea kernel slices are pressed and the crude oil is condensed and then cold-extracted to recover the fragrance, and then the fragrance is added to obtain the finished oil.

2. The method according to claim 1, characterized in that In step (1), the dual-frequency ultrasonic cleaning is performed at 28 kHz for 2-3 minutes and then switched to 40 kHz for 1-2 minutes; the water wave vibration cleaning water flow rate is 0.8-1.2 m / s and the time is 6-8 minutes; the gravity drop height is 1-1.5 m, and the wind speed of the thermal air separation is 6-10 m / s.

3. The method according to claim 1, characterized in that In step (3), the dual-spectrum color sorting adopts RGB+near-infrared dual-mode recognition, and the absorbance of the near-infrared spectrum at 1740nm is ≥0.3 as the mold judgment threshold; the CCD imaging frequency of the dual-spectrum color sorting machine is ≥8000 frames / second.

4. The method according to claim 1, wherein In the step (2), in the tea seed kernels with the tea seed husks retained, the mass ratio of the tea seed kernels to the tea seed husks is 90:

10.

5. The method according to claim 1, wherein The pressing treatment in step (7) is carried out under the conditions of 120-130° C. and 20-25 MPa.

6. The method according to claim 1, characterized in that The step (7) of condensing and recovering the aroma is as follows: the squeezing waste gas is subjected to a three-stage gradient condensation system to recover the aroma substances, and the condensation temperature gradient is -5±1°C→-15±1°C→-25±1°C to obtain a condensate.

7. The method according to claim 1, characterized in that The step (7) of low temperature cold extraction is as follows: the crude oil is centrifuged at ≤40°C and 8000-10000rpm to remove impurities until the residual amount is ≤0.1%, thereby obtaining refined oil.

8. The method according to claim 1, characterized in that In step (7), the aroma is added back to the refined oil by adding condensate in an amount of 0.05% to 0.3% of the weight of the refined oil.