阅读说明：本技术 一种富硒菜籽油的加工方法及其产品 (Processing method of selenium-rich rapeseed oil and product thereof ) 是由 孟资宽 任元元 邹育 张星灿 王拥军 王波 于 2019-10-28 设计创作，主要内容包括：本发明公布了一种富硒菜籽油的加工方法及其产品,包括采用冻融法对油菜籽微波破壁,并采用低温压榨方法压榨出毛油,利用亚临界方法对菜饼进行萃取处理,得到浸出毛油；将毛油进行超声波辅助磷酸脱胶,然后进行脱酸、脱水及脱色；本发明采用富硒油菜籽并采用变温冷冻破壁工艺,有助于提高菜籽的出油率和菜籽油中的硒含量；本发明采用低温压榨和亚临界萃取的方法使菜籽油的风味和营养物质得到更好的保留；本发明采用超声波辅助磷酸脱胶,脱胶效率高,脱胶时间大大缩短。(The invention discloses a processing method of selenium-rich rapeseed oil and a product thereof, which comprises the steps of breaking the wall of rapeseed by microwave by adopting a freeze-thaw method, squeezing out crude oil by adopting a low-temperature squeezing method, and extracting rapeseed cakes by using a subcritical method to obtain leached crude oil; carrying out ultrasonic-assisted phosphoric acid degumming on the crude oil, and then carrying out deacidification, dehydration and decoloration; the invention adopts the selenium-rich rapeseeds and the variable-temperature freezing wall-breaking process, which is beneficial to improving the oil yield of the rapeseeds and the selenium content in the rapeseed oil; the method adopts the methods of low-temperature squeezing and subcritical extraction to better reserve the flavor and nutrient substances of the rapeseed oil; the invention adopts ultrasonic wave to assist phosphoric acid for degumming, the degumming efficiency is high, and the degumming time is greatly shortened.)

1. The processing method of the selenium-rich rapeseed oil is characterized by comprising the following steps:

(1) removing impurities: pretreating rapeseeds, removing impurities, cleaning, filtering and drying until the water content of the rapeseeds is 10% -15%;

(2) freeze thawing and microwave: freezing the rapeseeds dried in the step (1) at a low temperature for 3-6 hours, taking out the rapeseeds, heating the rapeseeds to 20-40 ℃, continuing low-temperature freezing and heating cyclic treatment, wherein the last time is low-temperature freezing, and performing microwave treatment on the rapeseeds subjected to the last low-temperature freezing for 10-15 min;

(3) squeezing: drying the rapeseeds subjected to microwave treatment in the step (2) until the water content is 6% -10%, frying at a lower temperature, squeezing, and separating to obtain primary tuber mustard seed oil and rapeseed cakes;

(4) and (3) extraction: mixing the rapeseed cake prepared in the step (3) with an extraction solvent, performing subcritical extraction to obtain an extraction liquid, and filtering and centrifuging the extraction liquid to obtain extracted rapeseed oil;

(5) degumming: respectively adding phosphoric acid into the primary tuber mustard seed oil obtained in the step (3) and the extracted rapeseed oil obtained in the step (4), and degumming under the ultrasonic condition;

(6) deacidifying and decoloring: respectively carrying out deacidification treatment, vacuum drying and decoloration treatment on the primary tuber mustard seed oil degummed in the step (5) and the extracted rapeseed oil degummed;

(7) blending: and (4) weighing and mixing the primary tuber mustard seed oil treated in the step (6) and the extracted rapeseed oil according to the proportion to prepare the selenium-rich rapeseed oil.

2. The processing method of the selenium-rich rapeseed oil according to claim 1, wherein the method for pretreating the rapeseed in the step (1) comprises the following steps: firstly, a fan is used for removing dust impurities in rapeseeds, and then small-particle-size impurities in the rapeseeds are removed by screening.

3. The processing method of the selenium-rich rapeseed oil according to claim 1, characterized in that in the step (2), the temperature of low-temperature freezing is-25 to-18 ℃, and the times of low-temperature freezing and temperature rising are 2-4 times.

4. The processing method of the selenium-rich rapeseed oil according to claim 1, wherein in the step (3), the frying of the rapeseed at a lower temperature comprises a pre-frying and a post-frying; the early frying temperature is 60-75 deg.C, and the early frying time is 25-40 min; the later parching temperature is 45-55 deg.C, and the later parching time is 15-30 min.

5. The processing method of selenium-rich rapeseed oil according to claim 1, wherein in the step (4), the extraction solvent is water, and the mass ratio of water to rapeseed cake is 8-15: 1.

6. the processing method of the selenium-rich rapeseed oil as claimed in claim 1, wherein in the step (4), the extraction pressure is 0.1-0.25MPa, the extraction temperature is 100-.

7. The processing method of the selenium-rich rapeseed oil according to claim 1, wherein in the step (5), the power of the ultrasonic wave is 100-.

8. The processing method of selenium-rich rapeseed oil according to claim 1, characterized in that in step (7), the mass ratio of the virgin rapeseed oil to the extracted rapeseed oil is 2-4: 1.

9. selenium-enriched rapeseed oil prepared by the processing method according to any one of claims 1-8.

Technical Field

The invention relates to the technical field of food processing, in particular to processing production of selenium-rich rapeseed oil and a product thereof.

Background

The rapeseed oil is one of the main edible oils in China, is rich in nutrition, contains oleic acid, linoleic acid, linolenic acid, tocopherol, brassicasterol and the like, and has an important effect on the balance of human nutrition. The nutrition and flavor of rapeseed oil are often closely related to the raw material selection and processing method.

Selenium is a trace mineral element essential to human bodies, and is distributed in tissues, organs and body fluid of the human bodies, so that the selenium has important effects on improving the immunity of the human bodies and preventing cancers. Under normal conditions, selenium can be discharged out of the body along with metabolism of the human body, so that the human body needs to supplement the selenium in a proper amount through diet, but at present, residents in China generally have the condition of selenium deficiency.

The selenium-rich rapeseed oil disclosed in patents CN 108641813a and CN 107090347a is obtained by selecting high-quality rapeseed to increase the content of selenium element in rapeseed oil, and the processing method is also a traditional high-temperature pressing method. At present, the research of squeezing the rapeseed oil at low temperature has been reported, the oil yield of the novel method is improved by 5-6%, and the oil in the subcritical extraction rapeseed cake is in the theoretical research stage at present, but the subcritical extraction method can be determined to effectively extract the rapeseed component. The traditional acid degumming method in rapeseed oil refining has certain limitation, and the degumming effect of the traditional acid degumming method can not meet the requirement of physical refining in many cases.

Therefore, a processing method for effectively improving the selenium content and the degumming efficiency of the rapeseed oil needs to be researched.

Disclosure of Invention

Aiming at the defects of the prior art, the invention provides a processing scheme for effectively improving the selenium content, the flavor quality and the degumming efficiency of the rapeseed oil, and the rapeseed oil produced by the method has higher selenium content, high degumming rate and rich nutrition.

The technical purpose of the invention is realized by the following technical scheme:

a processing method of selenium-rich rapeseed oil comprises the following steps:

(1) removing impurities: pretreating rapeseeds, removing impurities, cleaning, filtering and drying until the water content of the rapeseeds is 10% -15%;

(2) freeze thawing and microwave: freezing the rapeseeds dried in the step (1) at a low temperature for 3-6 hours, taking out the rapeseeds, heating the rapeseeds to 20-40 ℃, continuing low-temperature freezing and heating cyclic treatment, wherein the last time is low-temperature freezing, and performing microwave treatment on the rapeseeds subjected to the last low-temperature freezing for 10-15 min;

(3) squeezing: drying the rapeseeds subjected to microwave treatment in the step (2) until the water content is 6% -10%, frying at a lower temperature, squeezing, and separating to obtain primary tuber mustard seed oil and rapeseed cakes;

(4) and (3) extraction: mixing the rapeseed cake prepared in the step (3) with an extraction solvent, performing subcritical extraction to obtain an extraction liquid, and filtering and centrifuging the extraction liquid to obtain extracted rapeseed oil;

(5) degumming: respectively adding phosphoric acid into the primary tuber mustard seed oil obtained in the step (3) and the extracted rapeseed oil obtained in the step (4), and degumming under the ultrasonic condition;

(6) deacidifying and decoloring: respectively carrying out deacidification treatment, vacuum drying and decoloration treatment on the primary tuber mustard seed oil degummed in the step (5) and the extracted rapeseed oil degummed;

(7) blending: and (4) weighing and mixing the primary tuber mustard seed oil treated in the step (6) and the extracted rapeseed oil according to the proportion to prepare the selenium-rich rapeseed oil.

As a further optimization scheme of the invention, the pretreatment step in the step (1) comprises the following steps: firstly, a fan is used for removing dust impurities in rapeseeds, and then small-particle-size impurities in the rapeseeds are removed by screening. The type of the fan and the aperture of the screening net can be adaptively selected according to the specific situation of impurities in the rapeseed oil, when the dust impurities are more or the rapeseed raw material is more, the fan with large air volume can be selected, and on the contrary, the fan with small air volume is selected; the aperture of the screening net can be adaptively selected according to the particle size of impurities in the rapeseeds.

As a further optimization scheme of the invention, in the step (2), the temperature of low-temperature freezing is-25 to-18 ℃, and the times of low-temperature freezing and temperature rising are both 2 to 4 times. The times of low-temperature freezing and temperature rise are not the same, and both are within the range. The rapeseeds frozen at low temperature are heated to a temperature range, and then the rapeseeds can be continuously frozen at low temperature.

As a further optimization scheme of the invention, in the step (3), the frying of the rapeseeds at lower temperature comprises early frying and later frying; the early frying temperature is 60-75 deg.C, and the early frying time is 25-40 min; the later parching temperature is 45-55 deg.C, and the later parching time is 15-30 min.

In a further optimized scheme of the invention, in the step (4), the extraction solvent is water, and the mass ratio of the water to the rapeseed cake is 8-15: 1.

as a further optimization scheme of the invention, in the step (4), the extraction pressure is 0.1-0.25MPa, the extraction temperature is 100-. The centrifugal speed, the centrifugal time and other parameters of the extraction liquid can be adjusted according to the content of the raw materials, the centrifugal time and other parameters can be set longer when the content of the extraction liquid is more, and the extraction liquid can be adaptively adjusted according to the prior art. The subcritical extraction of the scheme is completed in a subcritical extraction kettle.

As a further optimization scheme of the invention, in the step (5), the power of the ultrasonic wave is 100-200W, the degumming temperature is 60-80 ℃, the addition amount of the phosphoric acid is 0.15-0.4% of the oil weight, and the concentration of the phosphoric acid is 80%. In the degumming process, after phosphoric acid is added, stirring and standing are needed, and then centrifugal degumming is carried out, wherein other parameters such as temperature, time, stirring speed, centrifugal speed and the like in the process can be set according to parameters in the prior art.

As a further optimization scheme of the invention, in the step (6), the deacidification treatment, the vacuum drying and the decoloration treatment methods of the degummed primary tuber mustard seed oil and the degummed extraction rapeseed oil are consistent. Preferably, the deacidification treatment is: adding the concentrationIs 10-14⁰Be alkali solution, the addition of which is 0.1-0.3% of the weight of the oil, and stirring and reacting for 30-60min at the temperature of 60-90 ℃; the decoloring treatment comprises the following steps: adding waste clay and activated carbon for decolorization and filtration, wherein the mass ratio of the waste clay to the activated carbon is 3-5: 1, the proportion of the waste argil and the activated carbon in the oil and the type of the alkali liquor can be adaptively adjusted according to the prior art. Deacidifying treatment, vacuum drying and decoloring treatment are common treatment methods in the rapeseed oil preparation process. The vacuum degree, temperature and drying time of vacuum drying can be set according to the vacuum drying parameters of the rapeseed oil in the prior art. Experimental parameters of the decolorization treatment such as temperature, stirring speed and the like can be set according to the decolorization treatment method of the rapeseed oil in the prior art.

As a further optimization scheme of the invention, in the step 7), the mass ratio of the primary tuber mustard seed oil to the extracted rapeseed oil is 2-4: 1.

the invention adopts a variable-temperature freeze-thaw microwave wall breaking method, damages the rapeseed structure, efficiently breaks biological cell walls, and improves the substance extraction effect. The wall breaking efficiency of rapeseeds can be effectively improved through the change of high and low temperatures and a microwave means, various components including selenium in the rapeseeds can be effectively extracted, and the oil yield of the rapeseeds can be improved.

The rapeseed and rapeseed cakes are respectively treated by a method combining a low-temperature squeezing method and subcritical extraction, the squeezing temperature is not higher than 70 ℃, the highest extraction temperature is 130 ℃, and the flavor components in the rapeseed oil in the whole process are less lost. The combined use of the two methods not only improves the quality of the rapeseed oil, but also improves the oil yield of the rapeseed oil. The low-temperature pressed rapeseed oil has small component loss and high oil yield, and improves the oil extraction efficiency and the content of effective components by utilizing the characteristics of accelerated mass transfer speed of subcritical extraction, obviously improved dissolving capacity and low extraction temperature.

The invention adopts the ultrasonic-assisted phosphoric acid degumming method to be applied to rapeseed oil refining degumming, and utilizes the physical characteristics of ultrasonic waves to be combined with the degumming reaction of the phosphoric acid method, thereby better improving the degumming efficiency. Phospholipid must be removed in the rapeseed oil refining process, and the degumming process seriously influences the normal operation of the subsequent oil refining process if the degumming process is not thorough. The ultrasonic technology is introduced to enhance the reaction of the strong acid and the phospholipid, so that the degumming time is shortened, and the degumming effect is improved.

The invention has the beneficial effects that:

1) according to the invention, the rapeseeds are treated by using a high-low temperature change and microwave treatment method, so that biological cell walls are efficiently crushed, the substance extraction effect is improved, the oil yield is improved, and the treated rapeseeds are more suitable for low-temperature squeezing;

2) according to the invention, a low-temperature squeezing method and subcritical extraction are combined, raw material oil and components are extracted as far as possible, and compared with a single technology or traditional high-temperature squeezing, the oil quality, flavor and yield are improved;

3) according to the invention, ultrasonic-assisted phosphoric acid is adopted for degumming, the degumming effect and efficiency are improved, the degumming rate is more than 94%, and the phosphorus content of the degummed rapeseed oil is less than 12 mg/kg.

Detailed Description

The present invention is described in detail below by way of examples, it should be noted that the following examples are only for illustrating the present invention and should not be construed as limiting the scope of the present invention, and that the non-essential modifications and adaptations by those skilled in the art according to the above disclosure will still fall within the scope of the present invention. The centrifugal speed and centrifugal time of the extraction liquid, the experimental parameters of the degumming process, and some undisclosed parameters of the deacidification treatment, the vacuum drying and the decoloration treatment can be set according to the conventional technical requirements.