Sweet orange oil and decoloring and fragrance-keeping method thereof
Through the combination of freezing and adsorbent, the problem of organic solvent consumption, pollution and aroma loss during the decolorization process of orange oil is solved, and the stability and natural feeling of color and aroma of orange oil is improved, while reducing energy consumption and pollution.
Patent Information
- Application Number
- CN202311757979.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2023-12-20
- Publication Date
- 2025-06-20
AI Technical Summary
The existing decolorization methods of sweet orange oil consume organic solvents, pollution, low aroma integrity, insufficient natural feeling and aroma loss.
The decolored orange oil was obtained by freezing the orange oil at -30-0°C and controlling the freezing rate, combined with the preheated adsorbent, stirring and suction filtration.
It achieves the stable color performance of sweet orange oil and the greater natural aroma expression, while also having the advantages of low energy consumption and pollution-free.
Smart Images
Figure CN120173672A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of daily chemical fragrances, and in particular to a sweet orange oil and a method for decolorizing and preserving its fragrance. Background Art
[0002] Fresh orange oil raw materials are widely used in fruity fragrances, but the problem of fading of fresh orange oil often causes the problem of unstable color and state of the finished products of downstream manufacturers using this type of fragrance. The current sweet orange oil decolorization methods on the market mainly include extraction method and adsorption method. The extraction method is to select a suitable organic solvent to separate the colored part in the sweet orange oil, and then retain the colorless part of the sweet orange oil by liquid separation or distillation. However, this method consumes a large amount of organic solvents and is easy to cause pollution, and the integrity of the aroma after separation is low; while the traditional adsorption method heats the fresh orange oil for a long time during the adsorption process, the naturalness of the obtained decolorized orange oil is insufficient, and the proportion of volatile components decreases, resulting in aroma loss and poor volatilization. Summary of the Invention
[0003] The purpose of the present invention is to overcome the deficiencies of the prior art and provide a sweet orange oil and a method for decolorizing and preserving its fragrance. The sweet orange oil processed by the method of the present invention has the advantages of stable color and state performance and stronger natural aroma expressiveness; moreover, it also has the advantages of low energy consumption and no pollution.
[0004] To achieve the above purpose, the technical solution adopted by the present invention is as follows: In the first aspect, the present invention provides a method for decolorizing and preserving the fragrance of sweet orange oil, comprising the following steps: (1) Freeze the sweet orange oil at -30 - 0 °C for 5 - 350 min, and the freezing rate is 0.5 - 2 °C / min; (2) Preheat the adsorbent at 50 - 350 °C for 3 - 300 min; (3) Add the frozen sweet orange oil and the preheated adsorbent into a reaction kettle, stir for 0.5 - 24 h, and obtain the decolorized sweet orange oil after suction filtration.
[0005] The components of sweet orange oil mainly include two categories: terpene compounds composed of sesquiterpenes and terpenes, and oxygen-containing compounds composed of higher alcohols, aldehydes, ketones, esters, etc. Among them, sesquiterpenes and terpenes account for 90 - 99% of the total amount, and its main component is limonene. Limonene is unstable to light and heat, and is easily oxidized and deteriorated, resulting in a decline in the quality of sweet orange oil, and it contributes little to the aroma. Although the oxygen-containing compounds only account for 1 - 10%, they are the main source of the aroma of sweet orange essential oil.
[0006] By controlling the freezing rate of sweet orange oil, the present invention can make the aroma of sweet orange oil more persistent. The inventor speculates that this may be because: during the freezing process of sweet orange oil, by controlling the freezing rate to control the growth rate of ice crystals, long-range ordered porous channels are formed in the sweet orange oil during freezing. As a result, the oxygen-containing compounds in the sweet orange oil can enter the porous channels. Since the temperature of the adsorbent after preheating is relatively high, when it comes into contact with the frozen sweet orange oil, the adsorbent starts to release heat and the sweet orange oil starts to melt. During the mixing process of the melted sweet orange oil and the adsorbent, the adsorbent will adsorb the pigments in the melted sweet orange oil, while the oxygen-containing compounds in the un-melted sweet orange oil, due to being stored in the long-range ordered porous channels, are not affected by the temperature of the adsorbent, enabling the aroma of the sweet orange oil to be persistent and not easily volatilized, thereby greatly improving the aroma and quality of the sweet orange oil.
[0007] Preferably, in the step (1), the freezing temperature is -20~-10°C and the freezing time is 100 - 250 min.
[0008] Preferably, in the step (1), the freezing rate is any one or the range value of two of 0.5°C / min, 0.8°C / min, 1°C / min, 1.5°C / min, 2°C / min.
[0009] Preferably, in the step (2), the preheating temperature of the adsorbent is 100 - 200°C and the preheating time is 150 - 250 min.
[0010] Preferably, in the step (2), the average particle size of the adsorbent is 100 - 200 mesh.
[0011] By mixing the sweet orange oil with an adsorbent of a specific particle size, the present invention is beneficial to improving the decolorization rate of the sweet orange oil. If the particle size of the adsorbent is too large, the specific surface area of the adsorbent is too small, resulting in a smaller contact area between the adsorbent and the sweet orange oil, and thus the pigments in the sweet orange oil cannot be well adsorbed. If the particle size of the adsorbent is too small, the adsorbent is prone to agglomeration, making it difficult to disperse the adsorbent evenly with the sweet orange oil, thereby affecting the decolorization rate of the sweet orange oil. Therefore, by limiting the particle size of the adsorbent within the above range, the present invention can greatly improve the decolorization rate of the sweet orange oil.
[0012] Preferably, in the step (2), the adsorbent is at least one of activated clay, activated carbon, and diatomite.
[0013] Preferably, in the step (3), the mass ratio of the adsorbent to the sweet orange oil is (2 - 40):(60 - 98).
[0014] More preferably, the mass ratio of the adsorbent to the sweet orange oil is 20:80.
[0015] Preferably, the stirring rate in step (3) is 100 - 500 rpm.
[0016] Preferably, anhydrous ethanol with a concentration of 50% is added to the used adsorbent in step (3), and the mass ratio of anhydrous ethanol to the adsorbent is (0.01 - 0.2):1.
[0017] By adding anhydrous ethanol to the adsorbent after mixing with sweet orange oil, the present invention enables the reuse of the adsorbent, which is beneficial to resource conservation and cost reduction.
[0018] In a second aspect, the present invention also provides a sweet orange oil prepared by the above method.
[0019] Compared with the prior art, the beneficial effects of the present invention are as follows: The sweet orange oil treated by the method of the present invention has the advantages of stable color and appearance and stronger expression of natural aroma; moreover, it also has the advantages of low energy consumption and no pollution. Description of the Drawings
[0020] Figure 1 is a process schematic diagram of the method for decolorizing and preserving the fragrance of the sweet orange oil of the present invention.
[0021] Figure 2 is a comparison schematic diagram of the sweet orange oil before and after decolorization of the present invention. Detailed Embodiments
[0022] To better illustrate the purpose, technical solution and advantages of the present invention, the present invention will be further described below in conjunction with specific embodiments, but the protection scope and implementation manner of the present invention are not limited thereto.
[0023] The materials, reagents, etc. used in the following embodiments are commercially available reagents and materials unless otherwise specified. Example 1
[0024] A method for decolorizing and preserving the fragrance of sweet orange oil includes the following steps: (1) Freeze the sweet orange oil (Chongqing Zhengyuan Trading Co., Ltd.) in a low-temperature freezer at a freezing temperature of -30°C for 100 min with a freezing rate of 0.5°C / min; (2) Preheat the activated clay in a forced-air oven at a preheating temperature of 200°C for 150 min, and the average particle size of the activated clay is 100 mesh; (3) Add the frozen sweet orange oil and the preheated adsorbent into a reaction kettle, with the mass ratio of the adsorbent to the sweet orange oil being 20:80, then stir at a speed of 100 rpm for 10 h, and obtain the decolorized sweet orange oil after vacuum filtration. Finally, add anhydrous ethanol with a concentration of 50% to the used adsorbent, which can be reused. Figure 2It can be seen that the decolorized sweet orange oil is colorless and transparent. Example 2
[0025] A method for decolorizing and preserving the fragrance of sweet orange oil, comprising the following steps: (1) Freeze the sweet orange oil in a low-temperature freezer at a freezing temperature of -30°C for 200 minutes with a freezing rate of 1°C / min; (2) Preheat the diatomite in a forced-air oven at a preheating temperature of 200°C for 200 minutes. The average particle size of the diatomite is 100 mesh; (3) Add the frozen sweet orange oil and the preheated adsorbent to a reaction kettle. The mass ratio of the adsorbent to the sweet orange oil is 20:80, and then stir at a speed of 200 rpm for 15 hours. After vacuum filtration, the decolorized sweet orange oil is obtained. Finally, add anhydrous ethanol with a concentration of 50% to the used adsorbent, which can be reused. Example 3
[0026] A method for decolorizing and preserving the fragrance of sweet orange oil, comprising the following steps: (1) Freeze the sweet orange oil in a low-temperature freezer at a freezing temperature of -30°C for 250 minutes with a freezing rate of 2°C / min; (2) Preheat the activated carbon in a forced-air oven at a preheating temperature of 200°C for 250 minutes. The average particle size of the activated carbon is 100 mesh; (3) Add the frozen sweet orange oil and the preheated adsorbent to a reaction kettle. The mass ratio of the adsorbent to the sweet orange oil is 20:80, and then stir at a speed of 500 rpm for 20 hours. After vacuum filtration, the decolorized sweet orange oil is obtained. Finally, add anhydrous ethanol with a concentration of 50% to the used adsorbent, which can be reused. Example 4
[0027] The difference from Example 2 is that in step (2), the average particle size of the diatomite is 150 mesh, and other steps are the same as those in Example 2. Example 5
[0028] The difference from Example 2 is that in step (2), the average particle size of the diatomite is 200 mesh, and other steps are the same as those in Example 2. Example 6
[0029] The difference from Example 2 is that in step (2), the preheating temperature is 100°C, and other steps are the same as those in Example 2. Example 7
[0030] The difference from Example 2 is that in step (2), the preheating temperature is 350°C, and other steps are the same as those in Example 2. Example 8
[0031] It is different from Example 2 in that the mass ratio of the adsorbent to the sweet orange oil in step (3) is 2:98, and the other steps are the same as those in Example 2. Example 9
[0032] It is different from Example 2 in that the mass ratio of the adsorbent to the sweet orange oil in step (3) is 10:90, and the other steps are the same as those in Example 2. Example 10
[0033] It is different from Example 2 in that the mass ratio of the adsorbent to the sweet orange oil in step (3) is 30:70, and the other steps are the same as those in Example 2. Example 11
[0034] It is different from Example 2 in that the mass ratio of the adsorbent to the sweet orange oil in step (3) is 40:60, and the other steps are the same as those in Example 2.
[0035] Comparative Example 1 It is different from Example 2 in that the freezing rate in step (1) is 0.2 °C / min, and the other steps are the same as those in Example 2.
[0036] Comparative Example 2 It is different from Example 2 in that the freezing rate in step (1) is 2.5 °C / min, and the other steps are the same as those in Example 2.
[0037] Comparative Example 3 It is different from Example 2 in that the average particle size of the diatomaceous earth in step (2) is 50 mesh, and the other steps are the same as those in Example 2.
[0038] Comparative Example 4 It is different from Example 2 in that the average particle size of the diatomaceous earth in step (2) is 250 mesh, and the other steps are the same as those in Example 2.
[0039] Comparative Example 5 It is different from Example 2 in that the preheating temperature in step (2) is 40 °C, and the other steps are the same as those in Example 2.
[0040] Comparative Example 6 It is different from Example 2 in that the preheating temperature in step (2) is 380 °C, and the other steps are the same as those in Example 2.
[0041] Experiment 1. The chemical composition analysis of the sweet orange oil and its decolorized liquid components was carried out on a GC-MS spectrometer under the following conditions: The carrier gas is helium (99.999%); the chromatographic column is HP-5 quartz capillary column (30m×0.25mm×0.25mm); the column flow rate is 1 mL / min; the temperature programming is as follows: the initial temperature is 40°C and is held for 5 min, then it rises to 250°C at a rate of 5°C / min and is held for 5 min. The inlet temperature is 50°C, and the split ratio is 50∶1; the mass spectrometry conditions are: the ion source temperature is 230°C, the quadrupole temperature is 150°C, and the interface temperature is 280°C; the ionization method is EI, the electron quantity is 70 eV, and the mass range is 35 - 350 AMU / s. The external standard method is used to determine the content loss rate (%) of limonene, citral, and linalool in the decolorized sweet orange oil. According to the standard curves of limonene, linalool, and citral, the contents of each component in the sweet orange oil before decolorization are calculated as follows: limonene 93.98%, linalool 0.92%, and citral 0.51%.
[0042] The content loss rate of each component in the decolorized sweet orange oil = (the content of each component in the sweet orange oil before decolorization - the content of each component in the decolorized sweet orange oil) / the content of each component in the sweet orange oil before decolorization * 100%.
[0043] The smaller the loss rates of linalool and citral, the less likely the aroma of the sweet orange oil is to volatilize.
[0044] 2. Determination of the decolorization rate: On a spectrophotometer, at a wavelength of 520 nm, using a 1-cm cuvette, with water as the reference, the absorbance is measured, and then the decolorization rate of the sweet orange oil is calculated according to the following calculation formula: Decolorization rate = (A - A1) / A * 100%.
[0045] 3. Stability: The decolorized sweet orange oils of the above-mentioned examples and comparative examples are respectively exposed to the air, and after two weeks, it is observed whether the color of the sweet orange oil changes and whether flocculation occurs.
[0046] 4. Sensory evaluation Select 50 professionals in the food-related field to form a sensory evaluation panel to evaluate the sensory properties of the decolorized sweet orange oils of the above-mentioned examples and comparative examples. Relevant training is carried out before the evaluation; avoid contact with pungent items 2 h before the evaluation; avoid discussion during the evaluation; after evaluating each sample, take a short break before evaluating the next sample. The full score is 10 points, and the result is the average value of the evaluations of 50 people, and then the rating is carried out. Before the evaluation, the decolorized sweet orange oils of the above-mentioned examples and comparative examples are placed for 2 h before the evaluation.
[0047] A: 9 - 10 points, with a strong fresh aroma and a rich orange aroma; B: 6 - 8 points, with a relatively strong aroma; C: 4 - 5 points, with a general aroma; D: 0 - 3 points, with a weak orange aroma.
[0048] The above experimental results are shown in Table 1.
[0049] Table 1
[0050] As can be seen from Table 1, by comparing Comparative Examples 1-2 with Example 2 respectively, it can be obtained that when the freezing rate is too low or too high, the loss rates of citral and linalool in the sweet orange oil after decolorization are higher than those in Example 2, indicating that the freezing rate will affect the aroma of sweet orange oil. This is because during the freezing process of sweet orange oil, the freezing rate affects the growth rate of ice crystals. If the freezing rate is too low or too high, long-range ordered porous channels cannot be formed in the sweet orange oil during freezing, resulting in the oxygen-containing compounds in the sweet orange oil not being able to enter the porous channels and being affected by the temperature of the adsorbent, thereby affecting the volatilization of the aroma of sweet orange oil. Therefore, by controlling the freezing rate of the present invention to be 0.5-2 °C / min, it is beneficial to the long-lasting non-volatilization of the aroma of sweet orange oil, thereby improving the aroma and quality of sweet orange oil. By comparing Comparative Examples 3-4 with Example 2 respectively, it can be obtained that when the particle size of the adsorbent is too large or too small, the decolorization rate of sweet orange oil is lower than that in Example 2, and there will also be phenomena such as color change and flocculation, indicating that the particle size of the adsorbent has a greater impact on the decolorization rate of sweet orange oil. Therefore, by limiting the particle size of the adsorbent to 100-200 mesh in the present invention, it is not only beneficial to improving the decolorization rate of sweet orange oil, but also beneficial to improving the stability of sweet orange oil.
[0051] By comparing Examples 8-11 with Example 2 in Table 1 respectively, it can be obtained that as the mass ratio of the adsorbent to the sweet orange oil gradually increases, the decolorization rate of the sweet orange oil first increases and then decreases, indicating that in the present invention, when the mass ratio of the adsorbent to the sweet orange oil is 20:80, the decolorization rate of the sweet orange oil is the best at this time.
[0052] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit the protection scope of the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present invention can be modified or equivalently replaced without departing from the essence and scope of the technical solutions of the present invention.
Claims
1. A method for decolorizing and preserving the fragrance of sweet orange oil, characterized in that, It includes the following steps: (1) Freeze sweet orange oil at -30 - 0°C for 5 - 350 min, with a freezing rate of 0.5 - 2°C / min; (2) Preheat the adsorbent at 50 - 350°C for 3 - 300 min; (3) Add the frozen sweet orange oil and the preheated adsorbent into a reaction kettle, stir for 0.5 - 24 h, and obtain decolorized sweet orange oil after suction filtration.
2. The method for decolorizing and preserving the fragrance of sweet orange oil according to claim 1, characterized in that, In step (1), the freezing temperature is -20~-10°C, and the freezing time is 100 - 250 min.
3. The method for decolorizing and preserving the fragrance of sweet orange oil according to claim 1, characterized in that, In step (2), the preheating temperature of the adsorbent is 100 - 200°C, and the preheating time is 150 - 250 min.
4. The method for decolorizing and preserving the fragrance of sweet orange oil according to claim 1, characterized in that, In step (2), the average particle size of the adsorbent is 100 - 200 mesh.
5. The method for decolorizing and preserving the fragrance of sweet orange oil according to claim 1, characterized in that, In step (2), the adsorbent is at least one of activated clay, activated carbon, and diatomite.
6. The method for decolorizing and preserving the fragrance of sweet orange oil according to claim 1, characterized in that, In step (3), the mass ratio of the adsorbent to sweet orange oil is (2 - 40):(60 - 98).
7. The method for decolorizing and preserving the fragrance of sweet orange oil according to claim 1, characterized in that, In step (3), the stirring rate is 100 - 500 rpm.
8. The method for decolorizing and preserving the fragrance of sweet orange oil according to claim 1, characterized in that, Add anhydrous ethanol with a concentration of 50% to the used adsorbent in step (3), and the mass ratio of anhydrous ethanol to the adsorbent is (0.01 - 0.2):
1.
9. Sweet orange oil prepared by the method for decolorizing and preserving the fragrance of sweet orange oil according to any one of claims 1-8.