Tea oil raw material initial impurity removal and flavor protection treatment method
By combining a mixed treatment solution of α-ketoglutaric acid, amino acids, and a eutectic solvent with gradient pressure separation and microwave heating, the problem of flavor substance loss during the initial impurity removal process of tea oil raw materials was solved, achieving efficient impurity removal and flavor preservation while reducing equipment costs and energy consumption.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- WUHAN MINGQIAO TECH CO LTD
- Filing Date
- 2026-04-07
- Publication Date
- 2026-06-05
AI Technical Summary
The existing tea oil raw material initial impurity removal technology is simple and cannot effectively remove the gum, wax and micro-impurities on the surface of tea seeds as well as the micro-impurities inside the tissue. This leads to a large loss of flavor substances in the subsequent refining process. In addition, the separation efficiency of impurity removal and aroma enhancement processes is low, and the equipment investment is large and the energy consumption is high.
A mixture of α-ketoglutaric acid, amino acids, and a low-melting-point solvent was used to treat the tea oil raw material. The mixture was then subjected to gradient pressure separation and microwave heating, combined with low-temperature nitrogen treatment, to remove impurities and preserve flavor. The specific steps included mixing and homogenization, gradient pressure separation, segmented microwave heating, and low-temperature nitrogen treatment.
It significantly increases the content of flavor compounds in tea oil, avoids the destruction of flavor compounds, reduces equipment costs and energy consumption, improves material flowability, and enhances the stability of subsequent pressing and oil extraction and equipment cleaning cycles.
Smart Images
Figure SMS_1
Abstract
Description
Technical Field
[0001] This invention relates to the field of food processing technology, and in particular to a method for initial impurity removal and flavor preservation treatment of tea oil raw materials. Background Technology
[0002] Camellia oil is a high-quality, highly nutritious, and easily digestible edible vegetable oil obtained from camellia seeds through processing and refining. It is a pure natural green health food. Camellia oil is rich in monounsaturated fatty acids (oleic acid content 75%-85%), which can effectively lower cholesterol and prevent cardiovascular and cerebrovascular diseases such as coronary heart disease and hypertension. At the same time, camellia oil contains abundant natural antioxidants, including vitamin E, polyphenols, and squalene, possessing excellent nutritional value and health benefits.
[0003] The processing of camellia oil generally includes steps such as color sorting, desiccant removal, impurity removal, loading and unloading, oilseed conveying, pressing, and refining. In existing technologies, the focus of camellia oil processing technology is usually on optimizing the pressing process, including different pressing and extraction methods (such as hot pressing, cold pressing, supercritical extraction, etc.) or refining processes such as deodorization, impurity removal, and decolorization of the crude oil after pressing, often neglecting the initial impurity removal process of the raw materials.
[0004] Existing initial impurity removal technologies for tea oil raw materials have the following shortcomings: 1. The impurity removal methods are limited. Current pretreatment typically only uses physical screening to remove visible impurities (such as moldy grains, discolored grains, and fruit shell fragments), but it cannot effectively remove the gum, wax, and microscopic impurities on the surface of the tea seeds, as well as those within the tissue. These impurities enter the crude oil during subsequent pressing, increasing the refining burden and requiring chemical refining at high temperatures, resulting in a significant loss of flavor substances and active ingredients. 2. The impurity removal process leads to flavor loss. In traditional impurity removal processes, tea seeds undergo sun-drying, multiple screenings, transportation, and temporary storage, resulting in prolonged exposure to air and continuous volatilization of aroma components from the surface and interior of the tea seeds. A large amount of the unique aroma and fruity flavor of natural tea oil is lost before pressing, resulting in a bland final product. 3. The separation of impurity removal and aroma enhancement processes leads to low efficiency, high equipment investment, and high energy consumption.
[0005] Therefore, how to efficiently remove impurities while preserving the natural flavor and active ingredients of tea oil is a technical challenge that urgently needs to be solved. Summary of the Invention
[0006] Therefore, this invention proposes a method for initial impurity removal and flavor preservation treatment of tea oil raw materials.
[0007] The technical solution of this invention is implemented as follows: A method for initial impurity removal and flavor preservation treatment of tea oil raw materials, the specific steps of which include: S1. Preparation of treatment solution: Mix α-ketoglutaric acid, amino acids and eutectic solvent, homogenize to obtain treatment solution; S2. Mix the color-sorted and desiccant-removed tea oil raw materials with the treatment liquid, separate impurities by gradient pressure, filter, and obtain the impurity-removed tea oil raw materials; S3. The tea oil raw material after impurity removal is microwave heated in stages, and then immediately subjected to low-temperature treatment after microwave heating to obtain tea oil raw material after impurity removal and flavor preservation. S4. After removing impurities and preserving flavor, the tea oil raw materials undergo subsequent loading and unloading, oil conveying, and pressing.
[0008] Furthermore, in step S1, the mass ratio of α-ketoglutaric acid, amino acid, and eutectic solvent is 1:0.5-0.8:10-15.
[0009] Furthermore, the amino acid is at least one of proline, glycine, or lysine.
[0010] Furthermore, the eutectic solvent is betaine and glycerol in a molar ratio of 1:2-3.
[0011] Furthermore, the water content of the eutectic solvent is 20%-30%.
[0012] Furthermore, in step S1, the homogenization is performed at 1000-2000 rpm for 3-5 minutes.
[0013] Furthermore, in step S2, the solid-liquid ratio of the tea oil raw material to the treatment liquid is 1:10-20 g / mL.
[0014] Furthermore, in step S2, the gradient pressure separation and impurity removal specifically involves: maintaining the pressure at 0.05-0.08 MPa for 5-10 minutes, increasing it to 8-10 MPa and maintaining it for 5-8 minutes, and then depressurizing to atmospheric pressure and maintaining it for 10-15 minutes.
[0015] Furthermore, in step S3, the segmented microwave heating includes: processing at 30-40℃ and 100-200W for 4-6 minutes, processing at 45-55℃ and 300-400W for 2-4 minutes, and processing at 58-65℃ and 450-500W for 1-2 minutes.
[0016] Furthermore, in step S3, the low-temperature treatment involves introducing nitrogen gas at 5-10°C and 5-10 m / s for 3-5 minutes.
[0017] Compared with the prior art, the beneficial effects of the present invention are: 1. The processing solution of this invention, by mixing α-ketoglutaric acid, amino acids, and a eutectic solvent, is used in the initial impurity removal process of tea oil raw materials. The processing solution penetrates into the interior of the tea oil raw material structure. α-ketoglutaric acid complexes with metal ions in the tea seeds, while the eutectic solvent softens the gums and waxes, thus softening impurities in the tea oil raw material and making them easier to remove. Simultaneously, the processing solution adjusts the pH to promote the dissolution of impurities without damaging the oil structure. Furthermore, during the impurity removal process, it can enhance aroma and preserve flavor, prevent oxidation, and significantly increase the content of flavor substances.
[0018] 2. This invention, through liquid softening, gradient impurity removal, microwave aroma enhancement, and cold nitrogen aroma fixation, not only removes impurities and preserves flavor but also significantly increases the content of flavor compounds, preventing their destruction, and at a low cost. Furthermore, the impurity removal and flavor preservation method of this invention improves material flowability, reduces the risk of material blockage in subsequent loading and unloading processes, enhances material integrity during conveying, improves the stability of subsequent oil extraction, reduces costs and energy consumption, and extends equipment cleaning cycles, showing promising application prospects. Detailed Implementation
[0019] To better understand the technical content of this invention, specific embodiments are provided below to further illustrate the invention.
[0020] Unless otherwise specified, the experimental methods used in the embodiments of this invention are all conventional methods.
[0021] Unless otherwise specified, all materials and reagents used in the embodiments of this invention are commercially available.
[0022] The pressing process of this invention is a cold pressing process with an infeed temperature of 80°C.
[0023] Example 1 A method for initial impurity removal and flavor preservation treatment of tea oil raw materials, the specific steps of which include: S1. Preparation of treatment solution: α-ketoglutaric acid, proline and eutectic solvent (betaine and glycerol in a molar ratio of 1:0.7:13, water content 25%) are mixed and homogenized at 1500 rpm for 4 min to obtain the treatment solution. S2. Mix the color-sorted and desiccant-removed tea oil raw materials with the treatment liquid at a solid-liquid ratio of 1:15 g / mL. Maintain the pressure at 0.07 MPa for 8 min, increase it to 9 MPa and maintain it for 7 min, depressurize to atmospheric pressure and maintain it for 13 min, filter, and obtain the tea oil raw materials after impurity removal. S3. The tea oil raw material after removing impurities is first microwaved at 35℃ and 150W for 5 minutes, then microwaved at 50℃ and 350W for 3 minutes, and finally microwaved at 60℃ and 480W for 1.5 minutes. After the microwave heating is completed, nitrogen gas at 8℃ and 8m / s is immediately introduced for 4 minutes to obtain tea oil raw material after removing impurities and preserving flavor. S4. After removing impurities and preserving flavor, the tea oil raw materials undergo subsequent loading and unloading, oil conveying, and pressing.
[0024] Example 2 A method for initial impurity removal and flavor preservation treatment of tea oil raw materials, the specific steps of which include: S1. Preparation of treatment solution: Mix α-ketoglutaric acid, proline and eutectic solvent (betaine and glycerol in a molar ratio of 1:0.5:10, with a water content of 20%) in a mass ratio of 1:0.5:10, and homogenize at 1000 rpm for 3 min to obtain the treatment solution. S2. According to the solid-liquid ratio of 1:10 g / mL, the color-sorted and de-scraped tea oil raw material is mixed with the treatment liquid, kept at 0.05 MPa for 5 min, increased to 8 MPa and kept at 5 min, depressurized to normal pressure and kept at 10 min, filtered, and the tea oil raw material after impurity removal is obtained. S3. The tea oil raw material after removing impurities is first microwaved at 30℃ and 100W for 4 minutes, then microwaved at 45℃ and 300W for 2 minutes, and finally microwaved at 58℃ and 450W for 1 minute. After the microwave heating is completed, nitrogen gas at 5℃ and 5m / s is immediately introduced for 3 minutes to obtain tea oil raw material after removing impurities and preserving flavor. S4. After removing impurities and preserving flavor, the tea oil raw materials undergo subsequent loading and unloading, oil conveying, and pressing.
[0025] Example 3 A method for initial impurity removal and flavor preservation treatment of tea oil raw materials, the specific steps of which include: S1. Preparation of treatment solution: α-ketoglutaric acid, proline and eutectic solvent (betaine and glycerol in a molar ratio of 1:0.8:15, water content 30%) are mixed and homogenized at 2000 rpm for 5 min to obtain the treatment solution. S2. Mix the color-sorted and desiccant-removed tea oil raw materials with the treatment liquid at a solid-liquid ratio of 1:20 g / mL. Maintain the pressure at 0.08 MPa for 10 min, increase it to 10 MPa and maintain it for 8 min, depressurize to normal pressure and maintain it for 15 min, filter, and obtain the tea oil raw materials after impurity removal. S3. The tea oil raw material after removing impurities is first microwaved at 40℃ and 200W for 6 minutes, then microwaved at 55℃ and 400W for 4 minutes, and finally microwaved at 65℃ and 500W for 2 minutes. After the microwave heating is completed, nitrogen gas at 10℃ and 10m / s is immediately introduced for 5 minutes to obtain tea oil raw material after removing impurities and preserving flavor. S4. After removing impurities and preserving flavor, the tea oil raw materials undergo subsequent loading and unloading, oil conveying, and pressing.
[0026] Comparative Example 1 The process involves color sorting, desiccant removal, impurity removal, loading and unloading, oilseed conveying, and pressing. The conventional impurity removal process is adopted, which involves selecting seeds, cleaning and grading, shelling and separating them after drying and storage, removing stones, removing iron by magnetic separation, shelling, and separating kernels and shells after shelling.
[0027] Comparative Example 2 The difference from Example 1 is that α-ketoglutaric acid is missing in the treatment solution, but otherwise it is the same as Example 1.
[0028] The initial impurity removal and flavor preservation treatment method for tea oil raw materials in this comparative example includes the following steps: S1. Preparation of treatment solution: Mix proline and eutectic solvent (betaine and glycerol in a molar ratio of 1:2, with a water content of 25%) at a mass ratio of 0.7:13 and homogenize at 1500 rpm for 4 min to obtain the treatment solution. S2. Mix the color-sorted and desiccant-removed tea oil raw materials with the treatment liquid at a solid-liquid ratio of 1:15 g / mL. Maintain the pressure at 0.07 MPa for 8 min, increase it to 9 MPa and maintain it for 7 min, depressurize to atmospheric pressure and maintain it for 13 min, filter, and obtain the tea oil raw materials after impurity removal. S3. The tea oil raw material after removing impurities is first microwaved at 35℃ and 150W for 5 minutes, then microwaved at 50℃ and 350W for 3 minutes, and finally microwaved at 60℃ and 480W for 1.5 minutes. After the microwave heating is completed, nitrogen gas at 8℃ and 8m / s is immediately introduced for 4 minutes to obtain tea oil raw material after removing impurities and preserving flavor. S4. After removing impurities and preserving flavor, the tea oil raw materials undergo subsequent loading and unloading, oil conveying, and pressing.
[0029] Comparative Example 3 The difference from Example 1 is that the eutectic solvent in the treatment solution is replaced with water, otherwise it is the same as Example 1.
[0030] The initial impurity removal and flavor preservation treatment method for tea oil raw materials in this comparative example includes the following steps: S1. Preparation of treatment solution: Mix α-ketoglutaric acid, proline and water in a mass ratio of 1:0.7:13 and homogenize at 1500 rpm for 4 min to obtain the treatment solution. S2. Mix the color-sorted and desiccant-removed tea oil raw materials with the treatment liquid at a solid-liquid ratio of 1:15 g / mL. Maintain the pressure at 0.07 MPa for 8 min, increase it to 9 MPa and maintain it for 7 min, depressurize to atmospheric pressure and maintain it for 13 min, filter, and obtain the tea oil raw materials after impurity removal. S3. The tea oil raw material after removing impurities is first microwaved at 35℃ and 150W for 5 minutes, then microwaved at 50℃ and 350W for 3 minutes, and finally microwaved at 60℃ and 480W for 1.5 minutes. After the microwave heating is completed, nitrogen gas at 8℃ and 8m / s is immediately introduced for 4 minutes to obtain tea oil raw material after removing impurities and preserving flavor. S4. After removing impurities and preserving flavor, the tea oil raw materials undergo subsequent loading and unloading, oil conveying, and pressing.
[0031] Comparative Example 4 The difference from Example 1 is that in step S2, the pressure is maintained at atmospheric pressure for 28 minutes, while the rest is the same as in Example 1.
[0032] The initial impurity removal and flavor preservation treatment method for tea oil raw materials in this comparative example includes the following steps: S1. Preparation of treatment solution: α-ketoglutaric acid, proline and eutectic solvent (betaine and glycerol in a molar ratio of 1:0.7:13, water content 25%) are mixed and homogenized at 1500 rpm for 4 min to obtain the treatment solution. S2. Mix the color-sorted and desiccant-removed tea oil raw materials with the treatment liquid at a solid-liquid ratio of 1:15 g / mL, treat under normal pressure for 28 min, filter, and obtain the tea oil raw materials after impurity removal. S3. The tea oil raw material after removing impurities is first microwaved at 35℃ and 150W for 5 minutes, then microwaved at 50℃ and 350W for 3 minutes, and finally microwaved at 60℃ and 480W for 1.5 minutes. After the microwave heating is completed, nitrogen gas at 8℃ and 8m / s is immediately introduced for 4 minutes to obtain tea oil raw material after removing impurities and preserving flavor. S4. After removing impurities and preserving flavor, the tea oil raw materials undergo subsequent loading and unloading, oil conveying, and pressing.
[0033] Comparative Example 5 The difference from Example 1 is that in step S3, the microwave treatment is only performed at 50°C and 350W for 9.5 minutes, while the rest is the same as in Example 1.
[0034] The initial impurity removal and flavor preservation treatment method for tea oil raw materials in this comparative example includes the following steps: S1. Preparation of treatment solution: α-ketoglutaric acid, proline and eutectic solvent (betaine and glycerol in a molar ratio of 1:0.7:13, water content 25%) are mixed and homogenized at 1500 rpm for 4 min to obtain the treatment solution. S2. Mix the color-sorted and desiccant-removed tea oil raw materials with the treatment liquid at a solid-liquid ratio of 1:15 g / mL. Maintain the pressure at 0.07 MPa for 8 min, increase it to 9 MPa and maintain it for 7 min, depressurize to atmospheric pressure and maintain it for 13 min, filter, and obtain the tea oil raw materials after impurity removal. S3. Microwave the purified tea oil raw material at 50℃ and 350W for 9.5 minutes. Immediately after the microwave heating is completed, nitrogen gas at 8℃ and 8m / s is introduced for 4 minutes to obtain the purified and flavor-preserving tea oil raw material. S4. After removing impurities and preserving flavor, the tea oil raw materials undergo subsequent loading and unloading, oil conveying, and pressing.
[0035] Test case Following the methods of Examples 1-3 and Comparative Examples 1-5, the residue content in the crude oil after pressing was detected, and the content of flavor compounds nonanal, hexanal, octanal, trans-2-nonenal and 2-pentylfuran in the final tea oil was detected. The results are shown in Table 1.
[0036] Table 1
[0037] As can be seen from Table 1, the processing method of the present invention can effectively remove impurities and preserve flavor, and significantly increase the content of flavor substances in tea oil.
[0038] 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 initial impurity removal and flavor preservation treatment of tea oil raw materials, characterized in that, The specific steps include: S1. Preparation of treatment solution: Mix α-ketoglutaric acid, amino acids and eutectic solvent, homogenize to obtain treatment solution; S2. Mix the color-sorted and desiccant-removed tea oil raw materials with the treatment liquid, separate impurities by gradient pressure, filter, and obtain the impurity-removed tea oil raw materials; S3. The tea oil raw material after impurity removal is microwave heated in stages, and then immediately subjected to low-temperature treatment after microwave heating to obtain tea oil raw material after impurity removal and flavor preservation. S4. After removing impurities and preserving flavor, the tea oil raw materials undergo subsequent loading and unloading, oil conveying, and pressing.
2. The method for initial impurity removal and flavor preservation treatment of tea oil raw materials as described in claim 1, characterized in that, In step S1, the mass ratio of α-ketoglutaric acid, amino acid and eutectic solvent is 1:0.5-0.8:10-15.
3. The method for initial impurity removal and flavor preservation of tea oil raw materials as described in claim 2, characterized in that, The amino acid is at least one of proline, glycine, or lysine.
4. The method for initial impurity removal and flavor preservation treatment of tea oil raw materials as described in claim 2, characterized in that, The eutectic solvent is betaine and glycerol in a molar ratio of 1:2-3.
5. The method for initial impurity removal and flavor preservation treatment of tea oil raw materials as described in claim 4, characterized in that, The water content of the eutectic solvent is 20%-30%.
6. The method for initial impurity removal and flavor preservation treatment of tea oil raw materials as described in claim 1, characterized in that, In step S1, the homogenization is performed at 1000-2000 rpm for 3-5 minutes.
7. The method for initial impurity removal and flavor preservation treatment of tea oil raw materials as described in claim 1, characterized in that, In step S2, the solid-liquid ratio of the tea oil raw material to the treatment liquid is 1:10-20 g / mL.
8. The method for initial impurity removal and flavor preservation treatment of tea oil raw materials as described in claim 1, characterized in that, In step S2, the gradient pressure separation and impurity removal specifically involves: maintaining the pressure at 0.05-0.08 MPa for 5-10 minutes, increasing it to 8-10 MPa and maintaining it for 5-8 minutes, and then depressurizing to atmospheric pressure and maintaining it for 10-15 minutes.
9. The method for initial impurity removal and flavor preservation treatment of tea oil raw materials as described in claim 1, characterized in that, In step S3, the segmented microwave heating includes: processing at 30-40℃ and 100-200W for 4-6 minutes, processing at 45-55℃ and 300-400W for 2-4 minutes, and processing at 58-65℃ and 450-500W for 1-2 minutes.
10. The method for initial impurity removal and flavor preservation treatment of tea oil raw materials as described in claim 1, characterized in that, In step S3, the low-temperature treatment involves introducing nitrogen gas at 5-10°C and 5-10 m / s for 3-5 minutes.