阅读说明：本技术 菜籽油乳化物和菜籽油以及它们的制备方法 (Rapeseed oil emulsion and rapeseed oil and preparation method thereof ) 是由 宫保文 张余权 洪丰 吕丹 徐珊珊 于 2020-05-07 设计创作，主要内容包括：本申请涉及菜籽油乳化物及其用途和制备方法。本申请还涉及由所述菜籽油乳化物制备的菜籽油以及包含所述菜籽油的调和油。所述菜籽油乳化物通过包括如下步骤的方法制备：1)在菜籽油或菜籽毛油中加入1-10重量％,优选3-7重量％的水并对其进行剪切而乳化；和2)将剪切而乳化后的菜籽油或菜籽毛油离心,弃去上清液,从而得到菜籽油乳化物。(The application relates to a rapeseed oil emulsion and application and a preparation method thereof. The application also relates to rapeseed oil prepared from the rapeseed oil emulsion and blend oil containing the rapeseed oil. The rapeseed oil emulsion is prepared by a method comprising the following steps: 1) adding 1-10 wt%, preferably 3-7 wt% of water to rapeseed oil or rapeseed crude oil and shearing to emulsify; and 2) centrifuging the sheared and emulsified rapeseed oil or crude rapeseed oil, and discarding the supernatant, thereby obtaining the rapeseed oil emulsion.)

1. A method for preparing a rapeseed oil emulsion, comprising the steps of:

1) adding 2-10 wt%, preferably 3-7 wt% of water to rapeseed oil or rapeseed crude oil and shearing to emulsify; and

2) and centrifuging the sheared and emulsified rapeseed oil or crude rapeseed oil, and discarding the supernatant to obtain the rapeseed oil emulsion.

2. The process according to claim 1, wherein 0.1 to 10 wt.%, preferably 0.3 to 5 wt.%, more preferably 0.5 to 3 wt.% of cake flour is added to the rapeseed oil or crude rapeseed oil before step 1), optionally the rapeseed oil or crude rapeseed oil is stirred for 0.5 to 3h, preferably 1 to 2h, after the addition of the cake flour, optionally the stirred rapeseed oil or crude rapeseed oil is centrifuged at 10000g, preferably 3000-7000g, optionally 0.5 to 5 wt.%, preferably 1.5 to 3 wt.% of water is added to the rapeseed oil or crude rapeseed oil before the addition of the cake flour and the centrifugation, optionally the centrifugation is carried out at 10000g, preferably 3000-7000g, optionally the rapeseed oil or crude rapeseed oil is stirred for 0.5 to 3h, preferably 1 to 2h before the addition of water, optionally, the rapeseed oil or crude rapeseed oil is heated to 50-80 ℃, preferably 60-70 ℃ before the water is added.

3. The process according to claim 1, wherein in step 1) the temperature of the water is 50-100 ℃, preferably 60-80 ℃, optionally the shearing in step 1) involves shearing at 8000-.

4. The method as claimed in claim 1, wherein the centrifugation in step 2) is carried out at 12000g of 5000-.

5. A rapeseed oil emulsion prepared by the method of any one of claims 1 to 4.

6. A process for preparing rapeseed oil comprising drying the rapeseed oil emulsion according to claim 5 to obtain the final rapeseed oil, preferably said drying is carried out under vacuum, preferably said drying is carried out at 50-150 ℃, preferably 70-120 ℃.

7. A process for preparing rapeseed oil comprising adding at least 1 wt%, preferably 3-10 wt% of a rapeseed oil emulsion according to claim 5 to a rapeseed oil product and drying to obtain the final rapeseed oil, preferably the drying is performed under vacuum, preferably the drying is performed at 50-150 ℃, preferably 70-120 ℃.

8. Use of a rapeseed oil emulsion according to claim 5 for increasing the sugar content or viscosity of rapeseed oil.

9. Rapeseed oil, which is prepared by a process according to claim 6 or 7, optionally having a total sugar content of 0.02-0.1 wt.%, preferably 0.04-0.07 wt.%.

10. A blend oil comprising the rapeseed oil of claim 9.

Technical Field

The present application relates generally to the field of food processing. More specifically, the application relates to a rapeseed oil emulsion, its use and a method of preparation. The application also relates to rapeseed oil prepared from the rapeseed oil emulsion and blend oil containing the rapeseed oil.

Background

With the continuous improvement of the living standard of people, the aromatic rapeseed oil with the traditional strong fragrance is deeply loved by consumers. The flavor oil is rich in flavor, smooth in taste and high in nutritive value, so that the flavor oil becomes a new research hotspot. In the cooking process, grease plays a very important role. First, it allows the cooking of food in a short time, with changes such as protein denaturation, starch gelatinization, cellulose softening, etc.; secondly, the oil and fat can provide color, fragrance, taste and shape for the cooked food, and can endow the cooked food with special flavor.

Because the compositions of the grease are different and the properties of the grease are different, different greases are selected according to raw materials and processes in cooking to achieve the cooking effect. In the cooking process, different oils have different influences on the taste, flavor and color of the dishes. The dish cooked by the aromatic rapeseed oil has bright color and mellow taste. However, the taste difference of the cooked dishes among different aromatic rapeseed oils is large because the viscosity difference among the aromatic rapeseed oils is large. At present, the research on the viscosity of rape oil in the article 'cold-pressed rape oil low-temperature refining technology and quality characteristic research thereof' shows that the viscosity is improved along with the increase of erucic acid content, and the viscosity difference depends on the content of trace components contained in the rape oil under the condition of the same fatty acid composition.

Summary of The Invention

This application is through extracting vegetable seed crude oil or rapeseed oil, obtains the fragrant rape seed oil of certain total sugar content, improves the glycolipid content in the rapeseed oil, improves the viscosity of rapeseed oil, obtains the fragrant rape seed oil product that has better culinary art characteristic, improves the culinary art consumption of fragrant rape seed oil and experiences.

The application provides the following technical scheme:

in a first aspect, the present application provides a method for preparing a rapeseed oil emulsion comprising the steps of:

1) adding 2-10 wt%, preferably 3-7 wt% of water to rapeseed oil or rapeseed crude oil and shearing to emulsify; and

2) and centrifuging the sheared and emulsified rapeseed oil or crude rapeseed oil, and discarding the supernatant to obtain the rapeseed oil emulsion.

In some embodiments, 0.1 to 10 wt.%, preferably 0.3 to 5 wt.%, more preferably 0.5 to 3 wt.% of cake flour is added to the rapeseed oil or rapeseed crude oil prior to step 1).

In some embodiments, the rapeseed oil or rapeseed crude oil is stirred for 0.5 to 3 hours, preferably 1 to 2 hours, after the addition of the meal.

In some embodiments, the stirred rapeseed oil or crude rapeseed oil is centrifuged at 10000g, preferably 7000g of 1000-.

In some embodiments, 0.5 to 5 wt.%, preferably 1.5 to 3 wt.% of water is added to the rapeseed oil or rapeseed crude oil and centrifuged before the cake meal is added.

In some embodiments, the centrifugation is carried out at 10000g, preferably 3000 7000g, 1000-.

In some embodiments, the rapeseed oil or rapeseed crude oil is stirred for 0.5 to 3 hours, preferably 1 to 2 hours, before centrifugation after addition of water.

In some embodiments, the rapeseed oil or crude rapeseed oil is heated to 50-80 ℃, preferably 60-70 ℃ before the water is added.

In some embodiments, in step 1), the temperature of the water is in the range of 50 to 100 ℃, preferably 60 to 80 ℃.

In some embodiments, the shearing in step 1) involves shearing at 8000-.

In some embodiments, in step 1), the rapeseed oil or crude rapeseed oil is heated to 50-100 ℃, preferably 60-80 ℃ before the water is added.

In some embodiments, in step 1), the sheared and emulsified rapeseed oil or rapeseed crude oil is stirred at 50-100 ℃, preferably 60-80 ℃ for 0.1-10 hours, preferably 0.3-7 hours.

In some embodiments, the centrifugation in step 2) is performed at 12000g of 5000-.

In a second aspect, the present application relates to a rapeseed oil emulsion prepared by the method of the first aspect.

In a third aspect, the present application relates to a method for preparing rapeseed oil comprising drying the rapeseed oil emulsion according to the second aspect to obtain the final rapeseed oil.

In some embodiments, the drying is performed under vacuum.

In some embodiments, the drying is carried out at 50 to 150 ℃, preferably 70 to 120 ℃.

In a fourth aspect, the present application relates to a method for preparing rapeseed oil, comprising adding at least 1 wt%, preferably 3-10 wt%, of the rapeseed oil emulsion according to the second aspect to a rapeseed oil product and drying to obtain the final rapeseed oil.

In some embodiments, the drying is performed under vacuum.

In some embodiments, the drying is carried out at 50 to 150 ℃, preferably 70 to 120 ℃.

In a fifth aspect, the present application relates to the use of the rapeseed oil emulsion according to the second aspect for increasing the sugar content or viscosity of rapeseed oil.

In a sixth aspect, the present application relates to rapeseed oil prepared by the method of the third or fourth aspect.

In some embodiments, the total sugar content in the rapeseed oil is 0.02-0.1 wt%, preferably 0.04-0.07 wt%.

In a seventh aspect, the present application relates to a blend oil comprising the rapeseed oil of the sixth aspect.

The method can extract the virgin rapeseed crude oil or the commercial rapeseed oil, and the highly viscous aromatic rapeseed oil is obtained. In addition, the method is simple in process, easy for industrial production and high in production efficiency.

Detailed description of the invention

The following definitions and methods are provided to better define the present application and to guide those of ordinary skill in the art in the practice of the present application. Unless otherwise defined, the terms of the present application are to be understood according to the conventional usage of those of ordinary skill in the relevant art.

Definition of

The term "about" as used herein refers to ± 10% of the number recited, for example about 1% refers to a range of 0.9% to 1.1%.

The term "canola oil" as used herein, also known as rapeseed oil, coriander oil, canola oil, sesame oil, canola oil, is an edible oil extracted from rapeseed. Is one of the main edible oils in China, is mainly produced in Yangtze river basin, southwest and northwest areas and the like, and has the first yield in the world. The rapeseed oil is golden yellow or brownish yellow in color and has a certain pungent smell. This odor is caused by the presence of a certain amount of sinapine, but is absent from the premium rapeseed.

The term "crude oil" as used herein refers to a primary oil obtained from vegetable oil stock without refining processing. The crude oil has simple processing technology, contains more impurities, is easy to oxidize and deteriorate, and is not suitable for long-term storage. The term "crude rapeseed oil" as used herein refers to a primary oil obtained from rapeseed without refining.

The term "cake flour" as used herein refers to rapeseed residue obtained by pressing rapeseed oil after cooking, wherein the rapeseed residue has a low water content and a low amount of oil remains.

The term "glycolipid" as used herein belongs to a lipid compound, which is widely present in various organisms. Glycolipids in nature can be divided into two main groups according to the kind of alcohol group in their components: glyceroglycolipids and glycosphingolipids. Glycosylated glycerolipids, known as glyceroglycolipids, are found in animal nervous tissue, plants and microorganisms, and are the major glycolipids in plants.

The term "viscosity" as used herein refers to the resistance that a fluid exhibits to flow. When a fluid (gas or liquid) flows, one part flows over the other part, and is subjected to resistance, which is the internal friction of the fluid. To enable fluid flow, tangential forces are applied in the direction of fluid flow to counter the resistance. According to consumer research, it is found that consumers prefer rapeseed oil with high viscosity, and the viscosity of the rapeseed oil is in positive correlation with the content of trace components.

The term "rapeseed oil product" as used herein refers to edible rapeseed oil commercially available from commercial sources or prepared by methods well known in the art.

Detailed Description

The glycolipids with the highest content in plants are the glyceroglycolipids, which are mainly mono-and digalactosylglycerides in rapeseed oil. This application is through extracting rapeseed oil or rapeseed oil crude oil, obtains the fragrant rapeseed oil of certain total sugar content, improves glycolipid content in the rapeseed oil, improves the rapeseed oil viscosity, obtains the fragrant rapeseed oil product that has better culinary art characteristic, improves the culinary art consumption of fragrant rapeseed oil and experiences.

In a first aspect, the present application provides a method for preparing a rapeseed oil emulsion comprising the steps of:

1) adding 2-10 wt%, preferably 3-7 wt%, more preferably 4-6 wt% of water to rapeseed oil or rapeseed crude oil and shearing to emulsify; and

2) and centrifuging the sheared and emulsified rapeseed oil or crude rapeseed oil, and discarding the supernatant to obtain the rapeseed oil emulsion.

In some embodiments, 0.1 to 10 wt.%, preferably 0.3 to 5 wt.%, more preferably 0.5 to 3 wt.% of cake flour is added to the rapeseed oil or rapeseed crude oil prior to step 1).

In some embodiments, the rapeseed oil or rapeseed crude oil is stirred for 0.5 to 3 hours, preferably 1 to 2 hours, after the addition of the meal.

In some embodiments, the stirred rapeseed oil or crude rapeseed oil is centrifuged at 10000g, preferably 7000g of 1000-.

In some embodiments, 0.5 to 5 wt.%, preferably 1.5 to 3 wt.% of water is added to the rapeseed oil or rapeseed crude oil and centrifuged before the cake meal is added.

In some embodiments, the centrifugation is carried out at 10000g, preferably 3000 7000g, 1000-.

In some embodiments, the rapeseed oil or rapeseed crude oil is stirred for 0.5 to 3 hours, preferably 1 to 2 hours, before centrifugation after addition of water.

In some embodiments, the rapeseed oil or crude rapeseed oil is heated to 50-80 ℃, preferably 60-70 ℃ before the water is added.

In some embodiments, in step 1), the temperature of the water is in the range of 50 to 100 ℃, preferably 60 to 80 ℃.

In some embodiments, the shearing in step 1) involves shearing at 8000-.

In some embodiments, in step 1), the rapeseed oil or crude rapeseed oil is heated to 50-100 ℃, preferably 60-80 ℃ before the water is added.

In some embodiments, in step 1), the sheared and emulsified rapeseed oil or rapeseed crude oil is stirred at 50-100 ℃, preferably 60-80 ℃ for 0.1-10 hours, preferably 0.3-7 hours.

In some embodiments, the centrifugation in step 2) is performed at 12000g of 5000-.

In a second aspect, the present application relates to a rapeseed oil emulsion prepared by the method of the first aspect.

In a third aspect, the present application relates to a method for preparing rapeseed oil comprising drying the rapeseed oil emulsion according to the second aspect to obtain the final rapeseed oil.

In some embodiments, the drying is performed under vacuum.

In some embodiments, the drying is carried out at 50 to 150 ℃, preferably 70 to 120 ℃.

In a fourth aspect, the present application relates to a method for preparing rapeseed oil, comprising adding at least 1 wt%, preferably 3-10 wt%, of the rapeseed oil emulsion according to the second aspect to a rapeseed oil product and drying to obtain the final rapeseed oil.

In some embodiments, the drying is performed under vacuum.

In some embodiments, the drying is carried out at 50 to 150 ℃, preferably 70 to 120 ℃.

In a fifth aspect, the present application relates to the use of the rapeseed oil emulsion according to the second aspect for increasing the sugar content or viscosity of rapeseed oil.

In a sixth aspect, the present application relates to rapeseed oil prepared by the method of the third or fourth aspect.

In some embodiments, the total sugar content in the rapeseed oil is 0.02-0.1 wt%, preferably 0.04-0.07 wt%.

In a seventh aspect, the present application relates to a blend oil comprising the rapeseed oil of the sixth aspect.

In this specification and claims, the words "comprise", "comprising" and "contain" mean "including but not limited to", and are not intended to exclude other moieties, additives, components, or steps.

It should be understood that features, characteristics, components or steps described in a particular aspect, embodiment or example of the present invention may be applied to any other aspect, embodiment or example described herein unless incompatible therewith.

The above disclosure generally describes the present application, which is further exemplified by the following examples. These examples are described merely to illustrate the present application and do not limit the scope of the present application. Although specific terms and values are employed herein, they are to be understood as exemplary and not limiting the scope of the application. Unless otherwise indicated, the experimental methods and techniques described herein are those conventional in the art. For other materials, equipment and the like not particularly noted in the manufacturer, they are generally commercially available.

Examples

In the examples and comparative examples of the present application, the raw materials used were all conventional ones and commercially available ones, unless otherwise specified.

Unless otherwise indicated, the various proportions used herein are by weight.

The measurement methods used in the following examples and comparative examples are briefly as follows:

the total sugar content of the oil is measured by using a BMG LABTECH brand FLUOstar Omega full-automatic multifunctional microplate reader, and the specific steps are as follows:

taking 1g rapeseed oil sample in a ground round bottom flask, transferring 25mL of 1mol/LKOH ethanol solution (aldehyde-free ethanol), placing in a water bath at 40 ℃ for 20min, dropwise adding 2mL of hydrochloric acid (mass fraction is 36%), heating in the water bath for 15min, adding 7mL of 1mol/LKOH solution, diluting to a constant volume of 25mL, and centrifuging. Precisely transferring 2mL of the supernatant into a 10mL centrifuge tube, evaporating to dryness below 80 ℃, and adding 2mL of distilled water to dissolve.

Adding 2mL of film reagent into a centrifuge tube, heating in a boiling water bath for 10min, centrifuging for 5min, removing a supernatant, adding 2mL of sulfuric acid-ammonium molybdate solution (ammonium molybdate-sulfuric acid solution: 2.5g of ammonium molybdate, adding 15mL of concentrated sulfuric acid, adding water to dissolve to 100mL), diluting a color developing agent, diluting to 100mL, standing for 30min, measuring absorbance by using an ultraviolet spectrophotometer, and detecting the galactose content on a galactose standard curve. The total sugar content is calculated as X ═ ρ × V × 100%/m, where X is the total sugar content; rho is the mass concentration of galactose found according to a standard curve, g/L; v is the constant volume, mL; m is the weight of the rapeseed oil, g.

The viscosity of the oil and fat is measured by an Anton Paar SVM3000 model kinematic viscometer by the following method:

sucking 6ml of oil sample by using an injector, connecting the oil sample to a sample inlet, slowly and uniformly injecting 2ml of liquid, rinsing according to a start, stopping rotating according to the start after rinsing for 15s, injecting 1ml of sample for measurement, and injecting 1ml of sample again for repeated measurement after recording data.

Example 1

Rapeseed oil was prepared by the following steps:

1. cleaning the rapeseed, and removing impurities such as straw, stones and the like in the rapeseed;

2. frying seeds to 170 deg.C, discharging, and oil pressing with oil press (Xiangge oil press, model px7) to obtain crude oleum Rapae;

3. heating rapeseed crude oil to 60 ℃, adding 1.5% of water, stirring for 1h, centrifuging 3000g, adding 0.5% cake powder (namely the residue of the rapeseed cake left after oil pressing in the step 2, wherein the residue contains a small amount of water and a small amount of grease), stirring for 1h, and centrifuging 3000g to obtain rapeseed oil;

4. heating oleum Rapae to 80 deg.C, adding 5% 80 deg.C hot water, shearing at 15000RPM (FLUKO FA25-Digital high shear emulsifying machine) for 1min, and heating and stirring at 80 deg.C for 0.5 hr;

5. adding water, shearing, and centrifuging emulsified rapeseed oil at 8000g for 10 min;

6. and (3) taking the centrifuged lower emulsion layer, and carrying out vacuum drying at 100 ℃ to obtain the high-viscosity rapeseed oil.

Example 2

Rapeseed oil was prepared by the following steps:

1. cleaning the rapeseed, and removing impurities such as straw, stones and the like in the rapeseed;

2. frying seeds to 170 deg.C, discharging, and oil pressing with oil press (Xiangge oil press, model px7) to obtain crude oleum Rapae;

3. heating rapeseed crude oil to 60 ℃, adding 1.5% of water, stirring for 1h, centrifuging 3000g, adding 0.5% cake powder (namely the residue of the rapeseed cake left after oil pressing in the step 2, wherein the residue contains a small amount of water and a small amount of grease), stirring for 1h, and centrifuging 3000g to obtain rapeseed oil;

4. heating oleum Rapae to 80 deg.C, adding 5% 80 deg.C hot water, shearing at 15000RPM (FLUKO FA25-Digital high shear emulsifying machine) for 1min, and heating and stirring at 80 deg.C for 0.5 hr;

5. adding water, shearing, and centrifuging emulsified rapeseed oil at 8000g for 10 min;

6. and taking 5g of the centrifuged lower emulsion layer, adding 100g of commercially available rapeseed oil product into the emulsion layer, and performing vacuum drying at 100 ℃ to obtain the high-viscosity rapeseed oil.

Example 3

Rapeseed oil was prepared by the following steps:

1. cleaning the rapeseed, and removing impurities such as straw, stones and the like in the rapeseed;

2. frying seeds to 170 deg.C, discharging, and oil pressing with oil press (Xiangge oil press, model px7) to obtain crude oleum Rapae;

3. heating rapeseed crude oil to 60 ℃, adding 1.5% of water, stirring for 1h, centrifuging 3000g, adding 0.5% cake powder (namely the residue of the rapeseed cake left after oil pressing in the step 2, wherein the residue contains a small amount of water and a small amount of grease), stirring for 1h, and centrifuging 3000g to obtain rapeseed oil;

4. heating oleum Rapae to 80 deg.C, adding 5% 80 deg.C hot water, shearing at 15000RPM (FLUKO FA25-Digital high shear emulsifying machine) for 1min, and heating and stirring at 80 deg.C for 0.5 hr;

5. adding water, shearing, and centrifuging emulsified rapeseed oil at 8000g for 10 min;

6. and taking 8g of the centrifuged lower emulsion layer, adding the 8g of emulsion layer into 100g of commercially available rapeseed oil product, and performing vacuum drying at 100 ℃ to obtain the high-viscosity rapeseed oil.

Example 4

Rapeseed oil was prepared by the following steps:

1. cleaning the rapeseed, and removing impurities such as straw, stones and the like in the rapeseed;

2. frying seeds to 170 deg.C, discharging, and oil pressing with oil press (Xiangge oil press, model px7) to obtain crude oleum Rapae;

3. heating rapeseed crude oil to 60 ℃, adding 1.5% of water, stirring for 1h, centrifuging 3000g, adding 0.5% cake powder (namely the residue of the rapeseed cake left after oil pressing in the step 2, wherein the residue contains a small amount of water and a small amount of grease), stirring for 1h, and centrifuging 3000g to obtain rapeseed oil;

4. heating oleum Rapae to 80 deg.C, adding 5% 80 deg.C hot water, shearing at 15000RPM (FLUKO FA25-Digital high shear emulsifying machine) for 1min, and heating and stirring at 80 deg.C for 0.5 hr;

5. adding water, shearing, and centrifuging emulsified rapeseed oil at 8000g for 10 min;

6. and taking 10g of the centrifuged lower emulsion layer, adding the 10g of emulsion layer into 100g of commercially available rapeseed oil product, and performing vacuum drying at 100 ℃ to obtain the high-viscosity rapeseed oil.

Example 5 example 14

Examples 5-14 the procedure for preparing the emulsion layer was essentially the same as in example 2, except that the procedure in step 4 was slightly different. The operation of examples 5-14 in step 4, which differs from example 2, is now set forth in the following table.

Comparative example 1

Rapeseed oil was prepared by the following steps:

1. cleaning the rapeseed, and removing impurities such as straw, stones and the like in the rapeseed;

2. frying seeds to 170 deg.C, discharging, and oil pressing with oil press (Xiangge oil press, model px7) to obtain crude oleum Rapae;

3. heating the crude rapeseed oil to 60 ℃, adding 1.5% of water, stirring for 1h, centrifuging 3000g, adding 0.5% cake powder (namely the residue of the cake left after the oil pressing in the step 2, wherein the residue contains a small amount of water and a small amount of grease), stirring for 1h, and centrifuging 3000g to obtain the rapeseed oil.

Comparative example 2

Rapeseed oil was prepared by the following steps:

1. cleaning the rapeseed, and removing impurities such as straw, stones and the like in the rapeseed;

2. frying seeds to 170 deg.C, discharging, and oil pressing with oil press (Xiangge oil press, model px7) to obtain crude oleum Rapae;

3. heating rapeseed crude oil to 60 ℃, adding 1% of water, stirring for 1h, centrifuging 3000g, adding 0.5% cake powder (namely the residue of the rapeseed cake left after oil pressing in the step 2, wherein the residue contains a small amount of water and a small amount of grease), stirring for 1h, and centrifuging 3000g to obtain rapeseed oil;

4. heating oleum Rapae to 80 deg.C, adding 1% 80 deg.C hot water, shearing at 15000RPM (FLUKO FA25-Digital high shear emulsifying machine) for 1min, and heating and stirring at 80 deg.C for 0.5 hr;

5. adding water, shearing, and centrifuging at 8000g for 10 min.

Comparative example 3

Rapeseed oil was prepared by the following steps:

1. cleaning the rapeseed, and removing impurities such as straw, stones and the like in the rapeseed;

2. frying seeds to 170 deg.C, discharging, and oil pressing with oil press (Xiangge oil press, model px7) to obtain crude oleum Rapae;

3. heating rapeseed crude oil to 60 ℃, adding 5% of water, stirring for 1h, centrifuging 3000g, adding 0.5% cake powder (namely the residue of the rapeseed cake left after oil pressing in the step 2, wherein the residue contains a small amount of water and a small amount of grease), stirring for 1h, and centrifuging 3000g to obtain rapeseed oil;

4. heating oleum Rapae to 80 deg.C, adding 5% 80 deg.C hot water, shearing (FLUKO FA25-Digital high shear emulsifying machine) at 20000RPM for 1min, and heating and stirring at 80 deg.C for 0.5 hr;

5. adding water, shearing, and centrifuging at 8000g for 10 min.

Comparative example 4

Rapeseed oil was prepared by the following steps:

1. cleaning the rapeseed, and removing impurities such as straw, stones and the like in the rapeseed;

2. frying seeds to 170 deg.C, discharging, and oil pressing with oil press (Xiangge oil press, model px7) to obtain crude oleum Rapae;

3. heating rapeseed crude oil to 60 ℃, adding 5% of water, stirring for 1h, centrifuging 3000g, adding 0.5% cake powder (namely the residue of the rapeseed cake left after oil pressing in the step 2, wherein the residue contains a small amount of water and a small amount of grease), stirring for 1h, and centrifuging 3000g to obtain rapeseed oil;

4. heating oleum Rapae to 80 deg.C, adding 5% 80 deg.C hot water, shearing at 5000RPM (FLUKO FA25-Digital high shear emulsifying machine) for 1min, and heating and stirring at 80 deg.C for 0.5 hr;

5. adding water, shearing, and centrifuging at 8000g for 10 min.

Comparative examples 2 to 4 cannot obtain an emulsion layer by centrifugation in step 5 as in examples 1 to 14.

The results of total sugar content and rapeseed oil viscosity in the rapeseed oils prepared in examples 1 to 14 and comparative example 1 are as follows:

	total sugar content in rapeseed oil (%)	Rapeseed oil viscosity (mPa. s)
			Example 1	0.246％	83.659
Example 2	0.041％	66.564
			Example 3	0.06％	68.235
Example 4	0.09％	70.892
			Example 5	0.050％	67.462
Example 6	0.040％	66.607
			Example 7	0.038％	66.483
Example 8	0.048％	67.334
			Example 9	0.051％	67.551
Example 10	0.050％	67.510
			Example 11	0.051％	67.552
Example 12	0.056％	68.015
			Example 13	0.031％	65.894
Example 14	0.043％	66.920
			Comparative example 1	0.024％	65.296

From the above results it can be seen that the rapeseed oils of examples 1-14 have a total sugar content and a viscosity which are superior to those of comparative example 1. It can be seen that the shear emulsification step in examples 1-14 is critical to obtain rapeseed oil with high sugar content and high viscosity.

It is to be understood that while the application is illustrated in certain forms, it is not limited to what has been shown and described herein. It will be apparent to those skilled in the art that various changes can be made without departing from the scope of the application. Such variations are within the scope of the claims of this application.