Oil body degreasing method based on edible oil and oil body membrane concentrate

Abstract

The invention provides an oil body degreasing method based on edible oil and an oil body membrane concentrate, and belongs to the field of grease and vegetable protein processing.The oil body degreasing method based on the edible oil comprises the following steps that oil seeds are subjected to pulp grinding, filtering, centrifugation and separation, and an oil body is obtained; and adding edible oil into the obtained oil body, shearing, centrifuging and separating to obtain oil and an oil body membrane concentrate. According to the oil body degreasing method, the oil body is cut open to release grease in the inner core of the oil body through the shearing action by using the non-polar solvent property of the edible oil, the grease is dissolved in the edible oil, finally, the oil and the oil body membrane are separated through centrifugation, the oil body degreasing method is easy to operate, an alkane organic solvent unfriendly to the environment is not used, the processing process is safer and more environmentally friendly, and the application prospect is wide. The obtained oil is transparent, shows the properties of edible oil and can be used as the edible oil without refining, and the obtained oil body membrane concentrate can be concentrated by more than 10 times compared with an oil body membrane in the oil body.

Description

Technical Field

[0001] The invention relates to the technical field of oil and vegetable protein processing, and in particular to an oil body degreasing method based on edible oil and an oil body membrane concentrate. Background Art

[0002] Oil bodies (oleosomes) are organelles in plant seed cells that store neutral lipids such as triglycerides. They are natural emulsified oil droplets and are used in skin care products and foods. For example, Canada's SembiosysGenetics extracts and purifies safflower oil bodies and uses them as a new type of cosmetic raw material; Japan's Fuji Oil Company has launched a new vegetable cream product with soybean oil bodies as the main ingredient. However, the oil bodies themselves not only contain a large amount of oil, but also need to be repeatedly washed with water during the extraction process to improve purity, which causes the resulting oil bodies to contain water. Therefore, the above-mentioned safflower oil bodies and soybean oil bodies need to be treated with preservatives as commodities to improve product stability. At present, safflower oil bodies are treated with preservatives, and the addition of preservatives will cause a certain degree of harm to consumers; soybean oil bodies are treated with high-temperature instantaneous sterilization for preservation, which increases the process flow.

[0003] The oil body is composed of an inner core and an outer membrane. The inner core is neutral lipids such as triglycerides and diglycerides, and the outer membrane is a single phospholipid layer biological membrane formed by phospholipids and membrane proteins (i.e., the oil body membrane, which accounts for 2% to 5% of the total oil body mass). The phospholipids and membrane proteins in the oil body membrane work together to give the oil body membrane excellent emulsification. At the same time, the phospholipids in the oil body membrane give the oil body membrane good physiological functionality. Therefore, researchers have tried to extract the oil body membrane from the oil body and apply it.

[0004] At present, there are two main ways to extract oil body membranes, organic solvent extraction and freeze-thaw method. The organic solvent extraction method is to add the oil body to the organic solvent, separate the oil and the oil body membrane by extraction, and obtain the oil body membrane; the organic solvent used in this method needs to be explosion-proof during use; the obtained oil needs to be desolvated and refined before it can be used, and the oil body membrane also needs to be desolvated before it can be used; after desolvation and other treatments, there will still be problems with organic solvent residues in the oil and oil body membrane. The freeze-thaw extraction method is to first freeze the oil body at -18 to -20℃ for several days and then thaw it. This method is inefficient and time-consuming and energy-consuming. Summary of the invention

[0005] In view of the technical problems existing in the background technology, the present application provides an oil body degreasing method and oil body membrane concentrate based on edible oil, aiming to solve the technical problems that the current methods for extracting oil body membranes are environmentally unfriendly, affect the properties of the products, have organic solvent residues, or are inefficient and energy-intensive.

[0006] In a first aspect, the present invention provides an oil degreasing method based on edible oil, comprising the following steps:

[0007] S1. Grinding, filtering, centrifuging and separating the oil seeds to obtain oil bodies;

[0008] S2. Adding edible oil to the oil body, shearing, centrifuging and separating to obtain oil and oil body membrane concentrate.

[0009] In the technical solution of the embodiment of the present application, the non-polar solvent property of edible oil is utilized, and the oil body is cut open by shearing to release the fat in the inner core of the oil body, so that it is miscible with the added edible oil, thereby making the oil body membrane dispersed in the oil (referring to the miscible product of edible oil and fat), and finally the oil and the oil body membrane are separated by centrifugation. The oil body degreasing method is simple to operate, does not use environmentally unfriendly alkane organic solvents, and the processing process is safer and greener. The obtained oil exhibits the properties of edible oil, and transparent edible oil can be obtained after natural sedimentation or filtration without refining. The obtained oil body membrane concentrate can be concentrated more than 10 times compared with the oil body membrane in the oil body.

[0010] In some embodiments, in step S2, the mass ratio of the oil body to the edible oil is 1:(1-11); the type of the edible oil corresponds to the oilseed.

[0011] In this embodiment, by controlling the mass ratio of the oil body and the edible oil, the shearing process can effectively shear the oil body into a hemispherical structure, and the edible oil can immediately dissolve in the fat in the cut oil body (because the edible oil is around the cut oil body), providing favorable conditions for the separation of the oil and the oil body membrane.

[0012] In some embodiments, the shearing time is 2 to 10 minutes, and the shearing speed is 15000 to 40000 rpm.

[0013] In this embodiment, by reasonably controlling the shearing time and shearing speed, the oil body can be ensured to be fully and effectively cut at an appropriate shearing time and shearing speed, thereby achieving better separation of the oil and the oil body membrane.

[0014] In some embodiments, the centrifugation is performed under the condition that the pH of the oil bodies is greater than or equal to 9 or less than or equal to 4.

[0015] In this embodiment, the pH value of the extracted oil bodies is controlled so that the oil bodies deviate from their isoelectric point, which is beneficial for the oil bodies to be dispersed, thereby facilitating the oil bodies to be fully cut during shearing and to be compatible with the surrounding edible oil; if the pH is at the isoelectric point of the oil bodies, the oil bodies will aggregate into clumps, which is not conducive to the oil bodies being sheared.

[0016] In some embodiments, step S1 specifically comprises: adding deionized water to the oil seeds for initial grinding for a preset time, adding a pH regulator to adjust the pH value to alkaline, grinding again for a preset time, filtering to obtain a slurry; centrifuging the slurry to separate a supernatant, and washing the supernatant with deionized water to obtain the oil body.

[0017] In this embodiment, the oil seeds are fully crushed in a step-by-step manner to release the oil bodies to the maximum extent; at the same time, a pH regulator is added between the initial refining and the secondary refining, and the pH regulator can be evenly dispersed during the secondary refining process, so that the pH of the resulting slurry is more uniform, providing favorable conditions for centrifugation.

[0018] In some embodiments, the cleaning is performed 1 to 3 times, and the mass fraction of water in the oil body is 15% to 50%.

[0019] In this embodiment, by reasonably controlling the number of cleaning times, impurities adsorbed on the surface of the oil body are fully removed, providing favorable conditions for the subsequent sufficient separation of the oil body and impurities; the water content in the oil body is controlled within a reasonable range to avoid excessive water content in the oil body affecting the damage to the oil body during the shearing process, that is, to avoid adverse effects on the demulsification process.

[0020] In some embodiments, the method further comprises the following step: S3, adding the edible oil to the oil body membrane concentrate, and obtaining a secondary oil body membrane concentrate through shearing, centrifugation and separation.

[0021] In this embodiment, edible oil is added to the oil body membrane concentrate again, and the oil impurities in the oil body membranes are further removed through shearing, centrifugation and separation to purify the oil body membrane concentrate.

[0022] In some embodiments, the shearing is performed in a blade beater or refiner.

[0023] In this embodiment, shearing is performed in a blade-type beater or refiner so that the rapidly rotating blades cut the oil body to release the fat.

[0024] In some embodiments, step S2 further comprises: drying the oil body membrane concentrate to obtain a solid product.

[0025] In this embodiment, the moisture in the oil body membrane concentrate is further removed by drying, so that the obtained oil body membrane concentrate is solidified, the product stability is improved, and the shelf life is extended.

[0026] In a second aspect, an embodiment of the present application provides an oil body membrane concentrate, which is prepared by the edible oil-based oil body degreasing method provided in the first aspect of the present application.

[0027] In the technical solution of the embodiment of the present application, edible oil is used to achieve oil body degreasing, which does not affect the quality of the obtained product, and the obtained oil and oil body membrane concentrate can be directly used.

[0028] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the technical solution of the present application, the following is a brief introduction to the drawings used in the present application. Obviously, the drawings described below are only some embodiments of the present application, and for ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0030] Figure 1 This is a diagram of the state of oil bodies and sunflower seed oil after mixing and shearing in Example 1 of the present application.

[0031] Figure 2 This is a graph of the oil obtained after centrifugation and filtration of the oil and oil body membrane concentrate in Example 1 of the present application.

[0032] Figure 3 This is the isoelectric point analysis diagram of the oil body obtained in Example 1 of the present application.

[0033] Figure 4 a is a diagram showing the separation effect of the oil and oil body membrane concentrate after centrifugation in Example 3 of the present application; 4b is a diagram showing the separation effect of the oil and oil body membrane concentrate after centrifugation in Comparative Example 21; 4c is a diagram showing the separation effect of the oil and oil body membrane concentrate after centrifugation in Comparative Example 22.

[0034] Figure 5 This is a diagram of the separation effect of oil and oil body membrane concentrate after centrifugation in Comparative Example 23 of the present application.

[0035] Figure 6 This is a diagram of the state of oil bodies and sunflower oil after mixing and shearing in Comparative Example 24 of the present application.

[0036] Figure 7 This is a diagram showing the separation effect of oil and oil body membrane concentrate after centrifugation in Comparative Example 24 of the present application.

[0037] Figure 8 a is a diagram showing the separation effect of oil and oil body membrane concentrate after centrifugation in Comparative Example 25 of the present application; Figure 8 b is Figure 8 Top view of a. DETAILED DESCRIPTION

[0038] The following embodiments of the technical solution of the present application are described in detail in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present application, and are therefore only used as examples, and cannot be used to limit the scope of protection of the present application.

[0039] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by technicians in the technical field to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" in the specification and claims of this application and the above-mentioned figure descriptions and any variations thereof are intended to cover non-exclusive inclusions.

[0040] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0041] Oil body membranes have great application prospects due to their excellent emulsification and good physiological functionality. Currently, the main methods for extracting oil body membranes are organic solvent extraction and freeze-thaw method. The organic solvent extraction process has safety hazards, is environmentally unfriendly, affects the properties of the product, and has organic solvent residues. The freeze-thaw method is inefficient and time-consuming and energy-consuming.

[0042] In order to solve the technical problems that the current methods for extracting oil body membranes are environmentally unfriendly, affect the properties of the products, have organic solvent residues or are inefficient and energy-intensive, the present application provides an oil body degreasing method and oil body membrane concentrate based on edible oil, wherein the non-polar solvent properties of edible oil are utilized to cut the oil bodies through shearing to release the oil in the inner core of the oil bodies, so that the oil bodies are soluble in the added edible oil, thereby dispersing the oil body membranes in the oil, and finally the oil and the oil body membranes are separated by centrifugation. The oil body degreasing method is simple to operate, does not use environmentally unfriendly alkane organic solvents, and the processing process is safer and greener and more environmentally friendly. The obtained oil is transparent after natural sedimentation or filtration, exhibits the properties of edible oil, and can be used as edible oil without refining. The obtained oil body membrane concentrate can be concentrated more than 10 times compared with the oil body membrane in the oil bodies.

[0043] In a first aspect, the present invention provides an oil degreasing method based on edible oil, comprising the following steps:

[0044] S1. Grinding, filtering, centrifuging and separating the oil seeds to obtain oil bodies;

[0045] S2. Add edible oil to the oil body, and obtain oil and oil body membrane concentrate through shearing, centrifugation and separation.

[0046] In the technical scheme of the embodiment of the present application, the oil seeds are firstly ground to destroy the cell walls of the oil seed cells and fully release the oil bodies; then, impurities such as residues are filtered to obtain a uniform slurry, and the slurry is centrifuged to separate the oil bodies and water in the slurry, thereby obtaining oil bodies; then, edible oil is added to the obtained oil bodies and sheared, and during the shearing process, the spherical oil bodies are sheared to form hemispherical shapes (i.e., demulsification), so that the oil in the inner core of the oil body is fully in contact with the edible oil and dissolved in the edible oil (i.e., the oil is dissolved by utilizing the non-polar solvent characteristics of the edible oil), and at the same time, the presence of the edible oil with relatively large viscosity prevents the oil body membrane from recovering to a spherical shape and wrapping the oil again, and at this time, the broken oil body membrane is uniformly dispersed in the edible oil; then, the oil and the oil body membrane are fully separated to form upper and lower layers through centrifugation, and oil (referring to the miscible substance of the edible oil and the inner core of the oil body) and oil body membrane concentrate are obtained after separation. The present application innovatively uses edible oil to replace organic solvents to degrease the oil bodies, that is, "de-oiling with oil". The obtained oil and oil body membrane concentrate do not contain organic solvents, which does not affect the quality of the obtained product. The obtained oil is transparent after natural sedimentation or filtration, showing the properties of edible oil, and can be used as edible oil without refining. The obtained oil body membrane concentrate can be concentrated more than 10 times compared with the oil body membrane in the oil body. The oil body degreasing method of the present application is simple to operate, does not use environmentally unfriendly alkane organic solvents, and the processing process is safer and greener and environmentally friendly. It has a great promoting effect on its practical application, and can obtain a high-content oil body membrane concentrate product.

[0047] Furthermore, in some embodiments, in step S2, the mass ratio of the oil body to the edible oil is 1:(1-11); the type of edible oil corresponds to the oil seed. For example, if the oil seed used is sunflower kernel, the edible oil used is sunflower oil.

[0048] In the technical solution of the embodiment of the present application, by controlling the mass ratio of the oil body and the edible oil to 1: (1 to 11), first, after adding edible oil to the oil body, a large amount of edible oil will evenly disperse the oil body; then shearing is performed, and the appropriate amount of edible oil not only enables the shearing process to effectively shear the oil body into a hemispherical structure, but also enables the edible oil to dissolve the oil in the oil body in time to form a structure similar to the edible oil wrapped in the broken oil film, avoiding the oil body film from wrapping the oil again, and providing favorable conditions for the separation of the oil and the oil body film. At the same time, the type of edible oil is matched with the oil seed to ensure that the oil in the oil body is the same as the type of edible oil, which not only allows the oil to be quickly and efficiently dissolved in the edible oil, but also does not change the properties of the edible oil after the obtained oil is dissolved in the edible oil. The obtained oil can be directly used after natural sedimentation or filtration.

[0049] Furthermore, in some embodiments, the shearing time is 2 to 10 minutes, and the shearing speed is 15000 to 40000 rpm.

[0050] In the technical solution of the embodiment of the present application, by reasonably controlling the shearing time and shearing speed, it is possible to ensure that the oil body is fully and effectively cut at an appropriate shearing time and shearing speed, thereby better separating the oil and the oil body membrane. If the shearing time is too short or the shearing speed is too low, the oil body cutting process cannot be carried out effectively, and the oil cannot be fully dissolved in the edible oil, which in turn affects the separation of the oil and the oil body membrane. As long as all the oil bodies are cut within the preset time during the shearing process, the edible oil and the oil in the cut oil body can be effectively contacted and dissolved smoothly. Further lengthening the shearing time and further accelerating the shearing speed have little effect on the separation and concentration of the oil body membrane.

[0051] Further, in some embodiments, centrifugation is performed under the condition that the pH of the oil body is greater than or equal to 9 or less than or equal to 4. Specifically, if centrifugation is performed under the condition that the pH of the oil body is greater than or equal to 9, then there is no need to adjust the pH value in step S2; if centrifugation is performed under the condition that the pH of the oil body is less than or equal to 4, then it is necessary to add a pH adjuster to adjust the pH value of the oil body to a preset range.

[0052] In the technical solution of the embodiment of the present application, the pH value of the oil body is controlled during the centrifugation process, so that the oil body deviates from its isoelectric point, which is conducive to the uniform dispersion of the oil body, thereby facilitating the oil body to be fully cut during shearing and quickly dissolve with the surrounding edible oil, thereby more fully achieving the centrifugal separation of the oil and the oil body membrane. If the pH is at the isoelectric point of the oil body, the oil body will aggregate into a mass, which is not conducive to the effective shearing of the oil body.

[0053] Further, in some embodiments, step S1 specifically includes: adding deionized water to the oil seeds for the first grinding for a preset time, adding a pH regulator to adjust the pH value to alkaline, grinding again for a preset time, filtering to obtain a slurry; centrifuging the slurry to separate the floating matter, and washing the floating matter with deionized water to obtain the oil body. Specifically, before grinding, the oil seeds are washed and soaked; after the first grinding, the pH value is adjusted to be greater than or equal to 9; washing the floating matter is to disperse the floating matter in deionized water, and then centrifuge to separate the floating matter from the deionized water to obtain the oil body.

[0054] In the technical solution of the embodiment of the present application, washing can remove impurities adsorbed on the surface of oil seeds, and soaking can make the oil seeds fully swell, which is beneficial to the refining process; then deionized water is added to the oil seeds to provide conditions for refining. In the specific refining process, the initial refining is first performed to initially crush the oil seeds, and the secondary refining is performed to further crush the oil seeds, that is, the oil seeds are fully crushed in a step-by-step manner to release the oil bodies to the greatest extent; at the same time, a pH regulator is added between the initial refining and the secondary refining. The pH regulator can be evenly dispersed during the secondary refining process, so that the pH of the resulting slurry is more uniform, providing favorable conditions for centrifugation. The centrifugation process adjusts the pH value to greater than or equal to 9, which can effectively remove a large amount of foreign proteins adsorbed on the surface of the oil body, so that the oil body and impurities are fully separated, and the purity of the resulting oil body is improved; the floating matter is washed with deionized water to further wash away the impurities and thus further improve the purity of the oil body to obtain a high-purity oil body, which is beneficial to the subsequent separation process of oil and oil body membrane, and is also beneficial to improving the purity of the resulting oil body membrane.

[0055] Furthermore, in some embodiments, the number of cleanings is 1 to 3 times, and the mass fraction of water in the oil body is 15% to 50%.

[0056] In the technical solution of the embodiment of the present application, by reasonably controlling the number of cleaning times, the impurities adsorbed on the surface of the oil body are fully removed, providing favorable conditions for the subsequent full separation of the oil body and impurities. The water content in the oil body is controlled within a reasonable range to avoid excessive water content in the oil body affecting the damage to the oil body during the shearing process, that is, to avoid adverse effects on the demulsification process; the oil body in the present application contains a certain amount of water, that is, there is no need to remove the water in the oil body by heating, avoiding the influence of the high-temperature water removal process on the properties of the oil body, and then avoiding the influence on the properties of the obtained oil and oil body membrane concentrate, so that the obtained oil and oil body membrane concentrate have better quality and can be stored stably for a long time. That is, the whole process of the present application is carried out at low temperature (referring to room temperature or below room temperature), without any heat treatment, the treatment process is safer and reduces heat energy consumption. In addition, if the water content in the oil body is too high, on the one hand, it is not easy to shear the oil body, and on the other hand, the oil is wrapped by a large amount of water after the oil body is sheared, and it cannot be effectively dissolved in the edible oil, so that the oil and oil body membrane cannot be effectively separated. At the same time, the presence of a large amount of water will promote the recovery of the oil body film, wrap the exposed oil again, and finally form an emulsion.

[0057] Furthermore, in some embodiments, the following step is also included: S3, adding edible oil to the oil body membrane concentrate, and obtaining a secondary oil body membrane concentrate through shearing, centrifugation and separation.

[0058] In the technical solution of the embodiment of the present application, edible oil is added to the oil body membrane concentrate again, and the oil impurities in the oil body membrane are further removed through shearing, centrifugation and separation to purify the oil body membrane concentrate.

[0059] Further, in some embodiments, the shearing is performed in a blade-type beater or refiner.

[0060] In the technical solution of the embodiment of the present application, the shearing is carried out in a blade-type pulper or refiner, and the oil body is cut by the fast-rotating blade to release the oil, thereby ensuring the smooth progress of the shearing process. The equipment used includes a pulper, a shearing machine or a centrifuge, which are mature in industrial production and have a large output, laying a solid foundation for the industrial production of the oil body deoiling process.

[0061] Furthermore, in some embodiments, step S2 further comprises: drying the oil body membrane concentrate to obtain a solid product. Specifically, the drying comprises spray drying, hot air drying and the like.

[0062] In the technical solution of the embodiment of the present application, the moisture in the oil body membrane concentrate is further removed by drying, so that the obtained oil body membrane concentrate is solidified, the product stability is improved, the shelf life is extended, and the storage and transportation are facilitated.

[0063] In a second aspect, an embodiment of the present application provides an oil body membrane concentrate, which is prepared by the edible oil-based oil body degreasing method provided in the first aspect of the present application.

[0064] In the technical solution of the embodiment of the present application, edible oil is used to achieve oil body degreasing without affecting the quality of the obtained product. The obtained oil and oil body membrane concentrate can be directly used. The obtained oil body membrane concentrate is rich in functional ingredients such as membrane proteins and phospholipids, has excellent emulsification and functionality, and can be used in the fields of food and cosmetics.

[0065] Some specific embodiments are listed below. It should be noted that the embodiments described below are exemplary and are only used to explain the present application, and should not be construed as limiting the present application. If specific techniques or conditions are not specified in the embodiments, the techniques or conditions described in the literature in this area or the product specifications are used. The reagents or instruments used without specifying the manufacturer are all conventional products that can be obtained commercially.

[0066] Example 1

[0067] An oil body degreasing method based on edible oil comprises the following steps:

[0068] S1. Wash 150g of sunflower seed kernels, soak overnight at 4°C, pour out the soaking liquid, wash twice, add deionized water to a total mass of 1500g, beat with a beater for 2min, adjust the pH of the homogenate to 9.5 with a NaOH solution, continue beating for 2min, and filter to obtain a slurry; centrifuge at a speed of 8500rpm for 30min, collect the floating material (i.e., oil body), add deionized water to the floating material to a total mass of 1500g, centrifuge again at a speed of 8500rpm for 30min, collect the floating material, and obtain the oil body washed once, and the mass fraction of water in the obtained oil body is about 20%. Take an appropriate amount of oil body, determine the solid content in the oil body by the dry constant weight method (and obtain the water content at the same time), then determine the protein content in the oil body after constant weight by the Kjeldahl nitrogen method, and calculate the protein dry basis content in the oil body according to the ratio of protein content to solid content.

[0069] S2, take an appropriate amount of oil body, add sunflower oil to the oil body, the mass ratio of oil body (pH of oil body is 9.5) and sunflower oil is 1:9, shear with a blade beater for 6min, the shearing speed is 20000rpm, then centrifuge for 15min at a speed of 4000rpm, separate the oil in the upper layer and the oil body membrane concentrate in the lower layer, and obtain oil and oil body membrane concentrate. The solid content in the oil body membrane concentrate is determined by dry constant weight method, and then the protein content in the oil body membrane concentrate after constant weight is determined by Kjeldahl nitrogen determination method, and the protein dry basis content in the oil body membrane concentrate is calculated according to the ratio of protein content and solid content. Finally, the oil body membrane concentration degree is calculated, and the oil body membrane concentration degree = protein dry basis content in the oil body membrane concentrate / protein dry basis content in the oil body, and the obtained oil body membrane concentration degree is 8.91 times.

[0070] Figure 1 is a state diagram of the oil body and sunflower seed oil after mixing and shearing in step S2 of Example 1, Figure 1 It can be seen that there are granular oil body membrane concentrates on the wall of the beaker. Figure 2 is a graph of the oil obtained after centrifugation and filtration of the oil and oil body membrane concentrate in Example 1, Figure 2 It can be seen that the resulting oil is clear and translucent.

[0071] Determination of the isoelectric point of the obtained oil body: add 9 times the mass of deionized water to the oil body obtained in step S1, disperse it evenly, and then adjust its pH to 7.0, 6.8, 6.6, 6.4, 6.2, 6.0, 5.8, 5.6, 5.4, 5.2, 5.0, 4.8 respectively with hydrochloric acid, let it stand for 7 minutes to obtain the following Figure 3 The state diagram shown in Figure 3 It can be seen that when the pH is 5.6, the lower layer of liquid is relatively clear and the upper layer is smaller in volume, indicating that the oil bodies are more densely aggregated. Therefore, the isoelectric point of the oil bodies is around pH 5.6.

[0072] Examples 2-4 and Comparative Examples 1-3

[0073] A method for degreasing oil based on edible oil, compared with Example 1, the difference is that in step S2, the shearing time is different, and the rest is roughly the same as Example 1, which will not be repeated here.

[0074] The concentration degree of the oil body membrane concentrates obtained in Examples 1-4 and Comparative Examples 1-3 was calculated, and the specific results are shown in Table 1.

[0075] Table 1 Oil body membrane concentration degree of Examples 1-4 and Comparative Examples 1-3

[0076]

[0077]

[0078] As can be seen from Table 1, as the shearing time increases, the degree of oil body membrane concentration increases first and then basically tends to be stable. This may be because as the shearing time continues to increase, the oil body is continuously sheared and damaged, so that it is fully in contact with the edible oil and dissolved in the edible oil, thereby better achieving effective separation of the oil in the oil body and the oil body membrane concentrate, thereby making the oil body membrane concentration degree higher. As the shearing time further increases (Comparative Example 3), the degree of oil body membrane concentration changes very little, which shows that further extending the shearing time has no obvious promoting effect on the miscibility of edible oil and the oil in the cut oil body, and it will also increase costs and reduce efficiency.

[0079] In addition, when the degree of oil body membrane concentration is low (Comparative Examples 1 and 2), the storage properties of the oil body membrane concentrate obtained after drying are poor.

[0080] Examples 5-9 and Comparative Examples 4-5

[0081] A method for degreasing oil bodies based on edible oil, compared with Example 3, the difference is that in step S2, the mass ratio of the oil bodies and the edible oil is different, and the rest is substantially the same as Example 3, which will not be repeated here.

[0082] The concentration degree of the oil body membrane concentrates obtained in Examples 5-9 and Comparative Examples 4-5 was calculated, and the specific results are shown in Table 2.

[0083] Table 2 Oil body membrane concentration degree of Examples 5-9 and Comparative Examples 4-5

[0084]

[0085]

[0086] As shown in Table 2, as the amount of edible oil increases, the degree of oil body membrane concentration continues to increase. This may be because the amount of edible oil continues to increase, and the oil after demulsification can be more fully dissolved in the edible oil, thereby promoting the effective separation of oil and oil body membrane concentrate. With the further increase in the amount of edible oil (Comparative Example 4), the degree of concentration of the obtained oil body membrane concentrate is basically stable, and the amount of edible oil used will also increase, increasing the processing capacity of centrifugal separation. When the amount of edible oil is too small (Comparative Example 5), the degree of concentration is only 3.48.

[0087] In addition, the oil body membrane concentrates obtained after drying in Examples 5 to 9 and Comparative Example 4 had good storage properties, while the storage properties of Comparative Example 5 were poor.

[0088] Examples 10-11 and Comparative Examples 6-7

[0089] A method for degreasing oil based on edible oil, compared with Example 3, the difference is that in step S2, the shear speed is different, and the rest is roughly the same as Example 3, which will not be repeated here.

[0090] The concentration degree of the oil body membrane concentrates obtained in Examples 10-11 and Comparative Examples 6-7 was calculated. The specific results are shown in Table 3.

[0091] Table 3 Oil body membrane concentration degree of Examples 10-11 and Comparative Examples 6-7

[0092]

[0093]

[0094] As shown in Table 3, with the increase of shear rate, the degree of oil body membrane concentration continues to increase, which means that the shear process can indeed cut the oil body, so that the edible oil and the oil exposed by the cut oil body are miscible, thereby achieving the separation of oil and oil body membrane concentrate. When the shear rate is 10000rpm and 5000rpm, the degree of concentration is small, which is 4.32 and 3.20 respectively, and the storage property of the oil body membrane concentrate obtained after drying is not good.

[0095] Example 12 and Comparative Examples 8-13

[0096] A method for degreasing oil bodies based on edible oil, compared with Example 3, the difference is that in step S2, the pH value of the centrifugation, that is, the pH value of the oil bodies, is different, and the rest is substantially the same as Example 3, which will not be repeated here. Specifically, before performing step S2, hydrochloric acid is first added to adjust the pH value of the oil bodies obtained in step S1 to a preset range.

[0097] The concentration degree of the oil body membrane concentrates obtained in Example 12 and Comparative Examples 8-13 was calculated. The specific results are shown in Table 4.

[0098] Table 4 Oil body film concentration degree of Example 12 and Comparative Examples 8-13

[0099] Example pH of oil bodies Oil body membrane concentration (fold) Example 3 9.5 6.94 Example 12 3.89 7.02 Comparative Example 8 7.00 5.35 Comparative Example 9 6.50 4.56 Comparative Example 10 6.00 4.70 Comparative Example 11 5.50 4.24 Comparative Example 12 4.83 4.35 Comparative Example 13 4.38 5.61

[0100] As can be seen from Table 4, as the pH value of the oil body gradually changes from alkaline to neutral and then to acidic, the degree of oil body membrane concentration basically shows a trend of first decreasing and then increasing. This is mainly because the more the pH of the oil body deviates from its isoelectric point (the isoelectric point of the oil body is around pH 5.6), the more conducive it is to the smooth progress of the shear process, and thus the more conducive it is to the concentration of the oil body membrane.

[0101] Examples 13-15 and Comparative Examples 14-17

[0102] A method for degreasing oil bodies based on edible oil, compared with Example 3, the difference is that before performing step S2, deionized water is added to the oil bodies obtained in step S1, the water content in the oil bodies is adjusted to a preset range, and the pH value is adjusted to 9.5, and the mass ratio of the oil bodies to sunflower oil is controlled to be 1:9. The rest is substantially the same as Example 3 and will not be repeated here.

[0103] The concentration degree of the oil body membrane concentrates obtained in Examples 13-15 and Comparative Examples 14-17 was calculated. The specific results are shown in Table 5.

[0104] Table 5 Oil body film concentration degree of Examples 13-15 and Comparative Examples 14-17

[0105] Example Mass fraction of water in oil (%) Oil body membrane concentration (fold) Example 3 20 6.94 Embodiment 13 30 6.82 Embodiment 14 40 6.08 Embodiment 15 50 5.53 Comparative Example 14 60 5.23 Comparative Example 15 70 4.35 Comparative Example 16 80 3.21 Comparative Example 17 90 2.24

[0106] As shown in Table 5, as the water content in the oil body increases, the concentration degree of the obtained oil body membrane concentrate gradually decreases. This is mainly because the presence of excess water affects the shearing of the oil body during the shearing process, and at the same time hinders the interaction between the fat and edible oil in the cut oil body. When the water content of the oil body is too low, it is necessary to use equipment with greater centrifugal force. At this time, the requirements for the centrifugal equipment used are very strict, which increases the production cost. Therefore, this method recommends using oil bodies with a water content of 15% to 50%.

[0107] In addition, the storage properties of the oil body membrane concentrates obtained after drying in Comparative Examples 14 to 17 became increasingly poor.

[0108] Examples 16-17 and Comparative Examples 18-19

[0109] A method for degreasing oil bodies based on edible oil, compared with Example 3, the difference is that in step S1, the number of times the oil bodies are washed is different, and the moisture content of the oil bodies obtained after different washing times is about 20%. The rest is roughly the same as Example 3 and will not be repeated here.

[0110] The concentration degree of the oil body membrane concentrates obtained in Examples 16-17 and Comparative Examples 18-19 was calculated. The specific results are shown in Table 6.

[0111] Table 6 Oil body film concentration degree of Examples 16-17 and Comparative Examples 18-19

[0112] Example Cleaning times (times) Oil body membrane concentration (fold) Example 3 1 6.94 Example 16 2 6.98 Embodiment 17 3 7.47 Comparative Example 18 0 2.64 Comparative Example 19 4 7.51

[0113] As can be seen from Table 6, as the number of oil body washings increases, the degree of oil body membrane concentration tends to increase. This is mainly because as the number of washings increases, the impurities on the surface of the oil body are removed more cleanly, thereby making the purity of the oil body higher and more conducive to the concentration of the oil body membrane. As the number of oil body washings further increases (Comparative Example 19), the degree of oil body membrane concentration tends to be basically stable, indicating that washing three times can basically remove the impurities adsorbed on the surface of the oil body. Further increasing the number of washings will reduce production efficiency and increase costs.

[0114] Embodiment 18

[0115] An oil degreasing method based on edible oil, compared with Example 1, is different in that it also includes the following steps:

[0116] S3, adding sunflower seed oil to the oil body membrane concentrate obtained in step S2, the mass ratio of sunflower seed oil being 9 times the mass of the oil body obtained in step S1, shearing for 6 minutes on a blade beater at a shearing speed of 20000 rpm, and then centrifuging for 15 minutes at a speed of 4000 rpm to separate the upper layer of oil and the lower layer of oil body membrane concentrate to obtain oil and oil body membrane concentrate. That is, in this embodiment, edible oil is used for extraction twice to obtain the final oil body membrane concentrate, and the degree of oil body membrane concentration is 10.11 times.

[0117] Comparative Example 20

[0118] A method for degreasing oil based on edible oil, compared with Example 18, the difference is that it also includes the following steps:

[0119] S4, adding sunflower seed oil to the oil body membrane concentrate obtained in step S3, the mass ratio of sunflower seed oil being 9 times the mass of the oil body obtained in step S1, shearing for 6 minutes on a blade beater at a shearing speed of 20000 rpm, and then centrifuging for 15 minutes at a speed of 4000 rpm to separate the upper layer of oil and the lower layer of oil body membrane concentrate to obtain oil and oil body membrane concentrate. That is, in this comparative example 20, edible oil is used for extraction three times to obtain the final oil body membrane concentrate, and the degree of oil body membrane concentration is 10.32 times.

[0120] From the data of Example 1, Example 18 and Comparative Example 20, it can be seen that when edible oil is used to extract the oil body twice, the concentration of the oil body membrane is greatly improved; when edible oil is used to extract the oil body three times, the concentration of the oil body membrane is basically stable. This is mainly because the membrane proteins and phospholipids in the oil body membrane have lipophilic regions, which will adsorb a part of the oil. The adsorbed part of the oil cannot be dissolved in the added edible oil, resulting in a limit value for the concentration of the oil body membrane. From Example 1, Example 18 and Comparative Example 20, it can be seen that the concentration limit of edible oil for the oil body membrane is about 10.32 times. From the perspective of processing efficiency and cost, it is sufficient to extract the oil body twice with edible oil.

[0121] Comparative Example 21

[0122] A method for degreasing oil bodies based on edible oil, compared with Example 3, the difference is that step S2 specifically includes adding sunflower oil to the oil bodies, the mass ratio of the oil bodies to the sunflower oil is 1:9, ultrasonically treating the mixture of the oil bodies and the sunflower oil in an ultrasonic wave, the ultrasonic time is 6 minutes, the ultrasonic intensity is 100 Hz, and then centrifuging at a speed of 4000 rpm for 15 minutes to separate the oil in the upper layer and the oil body membrane concentrate in the lower layer to obtain oil and oil body membrane concentrate, and the concentration degree of the sunflower oil body membrane is 1.62 times.

[0123] Comparative Example 22

[0124] A method for degreasing oil bodies based on edible oil, compared with Example 3, the difference is that step S2 specifically includes adding sunflower oil to the oil bodies, the mass ratio of the oil bodies to the sunflower oil is 1:9, homogenizing the mixture of the oil bodies and the sunflower oil in a homogenizer, the homogenization time is 6 minutes, the homogenization pressure is 30MPa, and then centrifuging at a speed of 4000rpm for 15 minutes to separate the oil in the upper layer and the oil body membrane concentrate in the lower layer to obtain oil and oil body membrane concentrate, and the concentration degree of the sunflower oil body membrane is 1.36 times.

[0125] Comparative Example 23

[0126] A method for degreasing oil bodies based on edible oil, compared with Example 3, the difference is that step S2 uses a freeze-thaw method, specifically, the oil bodies are frozen at -20°C for 72 hours, thawed at 40°C, and then centrifuged at 4000 rpm for 15 minutes to separate the oil in the upper layer and the oil body membrane concentrate in the lower layer to obtain oil and oil body membrane concentrate, and the oil body membrane concentration degree is 2.85 times.

[0127] From the data of Comparative Examples 21-22, it can be seen that compared with shearing, the concentration degree of the obtained oil body membrane concentrate is significantly reduced when the mixture of oil body and sunflower oil is treated by ultrasound or homogenization. This is mainly because the use of ultrasound or homogenization treatment makes the oil body particles finer and thus the mixture of oil body and sunflower oil forms a uniform and stable system, which cannot effectively separate the oil and the oil body membrane concentrate, resulting in a decrease in the concentration degree of the oil body membrane. From the data of Comparative Example 23, it can be seen that the use of freeze-thaw treatment is not only inefficient (long time, high energy consumption), but also the concentration degree of the obtained oil body membrane is small.

[0128] At the same time, by Figure 4 a (the upper layer in the figure is oil, and the lower white milky substance is the oil body membrane concentrate). In Example 3, after centrifugal separation, the lower layer of the oil body membrane concentrate precipitate is relatively small, indicating that the obtained concentrate contains less impurities (i.e., the oil in the oil body core is effectively removed), the obtained concentrate has a higher purity, and the oil body membrane concentration effect is better. Figure 4 b and 4c show that after centrifugal separation in Comparative Examples 21 and 22, the oil body membrane concentrate in the lower layer has a significantly larger amount of precipitate, indicating that the concentrate contains more impurities and the oil body membrane concentration effect is poor. Figure 5 It is further explained that the degree of concentration of the oil body membrane obtained by the freeze-thaw treatment is small.

[0129] Comparative Example 24

[0130] A method for degreasing oil bodies based on edible oil, compared with Example 1, the difference is that in step S1, deionized water is added to the obtained oil bodies so that the mass fraction of water in the oil bodies is 90%, that is, an oil body dispersion with a mass concentration of 10% is obtained, and its pH value is adjusted to 9.5, the mass of the sunflower oil used in step S2 is the same as the mass of the oil bodies in the above-mentioned oil body dispersion, and the rest is substantially the same as Example 1 and will not be repeated here.

[0131] During the experiment, it was found that after shearing, the Figure 6 The homogeneous emulsion shown in the figure was centrifuged to obtain Figure 7 The results shown. Figure 7 It can be seen that after centrifugation, a floating cream layer is formed in the upper layer and an emulsion is formed in the lower layer, which indicates that the edible oil used in this comparative example is emulsified by the oil body instead of participating in the demulsification of the oil body.

[0132] Comparative Example 25

[0133] A method for degreasing oil bodies based on edible oil, compared with Example 1, the difference is that the edible oil in step S2 is replaced with a mixture of phosphoric acid and nonanoic acid. Specifically, the oil body is first diluted with 4 times the mass of deionized water, and then the pH of the system is adjusted to the isoelectric point of the oil body with a phosphoric acid solution, and nonanoic acid is added to break the emulsification, and the amount of nonanoic acid added is 2.0% of the mass of the oil body. The rest is substantially the same as Example 1 and will not be repeated here.

[0134] During the experiment, it was found that a uniform emulsion was formed after shearing, and after centrifugation, the following Figure 8 The results shown. Figure 8 It can be seen that the upper layer forms a floating cream layer and a small amount of free oil, and the lower layer forms an emulsion. The floating cream layer was tested and calculated, and the results showed that the concentration degree of the oil body membrane was 2.59. This shows that this method can indeed demulsify to a certain extent, but the concentration effect on the oil body membrane is not good. At the same time, the obtained oil body membrane concentrate contains phosphoric acid and nonanoic acid, which greatly affects the purity and properties of the oil body membrane concentrate. Because the oil body membrane component in the oil body accounts for about 2% to 5% of the total oil body, when 2% nonanoic acid is added (in addition to phosphoric acid for adjusting pH), nonanoic acid and phosphoric acid will greatly reduce the purity of the oil body membrane and will greatly change the properties of the obtained oil body membrane.

[0135] It should be noted that the present application is not limited to the above-mentioned embodiments. The above-mentioned embodiments are only examples, and the embodiments having the same structure as the technical idea and exerting the same effect within the scope of the technical solution of the present application are all included in the technical scope of the present application. In addition, without departing from the scope of the main purpose of the present application, various modifications that can be thought of by those skilled in the art to the embodiments and other methods of combining some of the constituent elements in the embodiments are also included in the scope of the present application.

Claims

1. A method for degreasing oil based on edible oil, characterized in that: The steps include: S1. Grinding, filtering, centrifuging and separating the oil seeds to obtain oil bodies; S2. Adding edible oil to the oil body, shearing, centrifuging and separating to obtain oil and oil body membrane concentrate.

2. The method for degreasing edible oil according to claim 1, characterized in that: In step S2, the mass ratio of the oil body to the edible oil is 1:(1-11); the type of the edible oil corresponds to the oilseed.

3. The method for degreasing oil bodies based on edible oil according to claim 2, characterized in that: The shearing time is 2 to 10 minutes, and the shearing speed is 15000 to 40000 rpm.

4. The method for degreasing edible oil according to claim 3, characterized in that: The centrifugation is performed under the condition that the pH of the oil body is greater than or equal to 9 or less than or equal to 4.

5. The method for degreasing oil bodies based on edible oil according to claim 1, characterized in that: Step S1 specifically comprises: adding deionized water to the oil seeds for initial grinding for a preset time, adding a pH regulator to adjust the pH value to alkaline, grinding again for a preset time, filtering to obtain slurry; centrifuging the slurry to separate the floating matter, and washing the floating matter with deionized water to obtain the oil body.

6. The method for degreasing edible oil-based oil bodies according to claim 5, characterized in that: The cleaning times are 1 to 3 times, and the mass fraction of water in the oil body is 15% to 50%.

7. The method for degreasing oil bodies based on edible oil according to claim 1, characterized in that: The following steps are also included: S3, adding the edible oil to the oil body membrane concentrate, and subjecting the mixture to shearing, centrifugation and separation to obtain a secondary oil body membrane concentrate.

8. The method for degreasing oil bodies based on edible oil according to claim 4, characterized in that: The shearing is carried out in a blade-type beater or refiner.

9. The method for degreasing oil bodies based on edible oil according to claim 1, characterized in that: Step S2 also includes: drying the oil body membrane concentrate to obtain a solid product.

10. An oil body membrane concentrate, characterized in that: The oil body degreasing method based on edible oil is used to prepare the oil body degreasing method.

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