JPH05320686A - Production of rapeseed oil - Google Patents

Abstract

PURPOSE:To provide a method for producing a rapeseed oil, which scarcely causes decomposition of rapeseed oil, producing little phospholipid difficult to degum, facilitates the purification of raw oil with the result of a high yield of rapeseed oil, and can give a pressed oil cake of good quality with a low glucosylate content. CONSTITUTION:Intact repeseed grains with a water content of 5-20wt.% are heated at 101-150 deg.C for 1 to 120min, and the tissual structure of the rapeseed is then destroyed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a high-quality oil from rapeseed, which is a raw material for vegetable oil.

[0002]

2. Description of the Related Art Conventionally, the production of rapeseed oil from rapeseed seeds has been
Rapeseed seeds are pressed (that is, flaked), then cooked (that is, heat-treated), and then pressed by a uniaxial press to obtain rapeseed crude oil. Rapeseed crude oil is also obtained from the pressed meal by extraction. Then, these crude oils are refined (that is, degumming treatment etc.) to produce refined rapeseed oil.

However, in the above conventional production method, the rapeseed oil component is significantly hydrolyzed, and a large amount of free fatty acids and hardly degummable phospholipids are produced. As a result, there is a problem that the crude oil itself cannot be obtained sufficiently, the refining of the crude oil is very difficult, and the refining yield is low.

Therefore, the rapeseed seeds are not compressed and remain in the form of round grains.
A method is proposed in which rapeseed oil is obtained by cooking at a low temperature of 90 ° C. or lower and then pressing (US Pat. No. 4024168).
issue).

[0005]

However, even in the above method, it is not possible to sufficiently suppress the generation of the hardly degummable phospholipid during the extraction treatment of the pressed meal, and the crude oil is not easy to purify. Further, the pressed meal also has a problem that it has a high content of glucosylate produced by the myrosinase enzyme and is not suitable for use as a feed material.

Therefore, the present invention reduces the decomposition of rapeseed oil,
Therefore, the occurrence of hardly degummable phospholipids is low, crude oil is easy to refine, and as a result, the yield of refined rapeseed oil is high, and a method for producing a rapeseed oil in which a high-quality pressed meal having a low glucosylate content is obtained, To aim.

[0007]

[Means for Solving the Problems] In order to achieve the above object, if the rapeseed seeds as whole grains are first cooked at a high temperature of 101 ° C. or higher before destroying the tissue of the rapeseed seed, excellent results will be achieved. This led to the completion of the present invention.

That is, the present invention has a water content of 5 to 20% by weight.
A method for producing rapeseed oil, which comprises heating the rapeseed seeds in the form of whole grains at 101 to 150 ° C. for 1 to 120 minutes and then destroying the tissue of the rapeseed seeds.

In the production method of the present invention, rapeseed seeds are cooked as round grains. The water content of rapeseed seeds is 5 to
It is 20% by weight, preferably 7-10% by weight. If the water content is less than 5% by weight, the inactivation of the enzyme will be insufficient and a sufficient effect cannot be expected. On the other hand, if it exceeds 20% by weight, the degreased lees are dried and the load increases, which is not preferable. Rapeseed seeds are used as round grains, but even if this is unpeeled,
It may be moulted.

The cooking temperature is 101-150 ° C, preferably
105 to 120 ° C. If the temperature is less than 101 ° C, the generation of hardly degummable phospholipids cannot be sufficiently suppressed, and if the temperature exceeds 150 ° C, the squeezed oil has a burnt odor. Also, it is not preferable in terms of energy efficiency. Cooking time is 1-12
It is 0 minutes, preferably 1 to 30 minutes. If it is less than 1 minute, the generation of hardly degummable phospholipids cannot be sufficiently suppressed, and if it exceeds 120 minutes, no more sufficient effect is exhibited. The cooker is not particularly limited, and may be any of vertical type, horizontal type, steam heating type and the like.

After the cooking, the rapeseed tissue is destroyed and rapeseed crude oil is collected. As such an oil collection method,
Pressed oil (ie pressed oil) is preferred. In the oil squeezing, a normal uniaxial squeezing machine may be used, but it is preferable to use a biaxial squeezing machine, particularly a biaxial squeezing machine described in JP-A-2-251397. By using this press, not only unpeeled round grains but also dehulled round grains (including fine seeds of half cracks or less) can be efficiently oiled. After cooking, the rapeseed tissue may be pre-destructed to a certain extent by pressing and then oil may be pressed. The pressing process may be performed by, for example, a roller or the like.

On the other hand, rapeseed crude oil is also extracted from the pressed meal by extraction treatment. As the extraction solvent, for example, an organic solvent,
Specific examples thereof include hexane, ethanol, isopropanol and the like. The extractor may be, for example, a rotocell type or the like. According to the present invention, the wastewater at the time of deoxidation is CO
D (chemical oxygen requirement) can be 0.03 kg / oil t or less. Further, the squeezed meal after extraction has a low glucosylate content of usually 0.05% by weight or less, and is optimal as, for example, a breeding feed.

Thereafter, the rapeseed crude oil described above and above is combined and refined. According to the present invention, these rapeseed crude oils can have an acid value of 1.5 or less and a P content of 30 ppm or less (degummed oil). Specifically, refining is performed by first degumming, deoxidizing, decolorizing, and deodorizing rapeseed crude oil. These may be processed according to a conventional method.
The degumming process removes the phospholipids contained in the rapeseed crude oil. The deoxidation treatment removes free fatty acids, unremoved phospholipids, and various metals.

According to the production method of the present invention, the purification yield of rapeseed oil can be increased to 95% or more.

[0015]

In the conventional method for producing rapeseed oil, rapeseed seeds are pressed and then cooked and heated. That is, enzymes in seeds that have been destroyed by tissue destruction (eg lipase, phospholipase, etc.)
After contact with the oil component, the temperature is temporarily raised to the most suitable temperature of the enzyme. As a result, the triglycerides and phospholipids in the oil component are rapidly hydrolyzed by the enzyme, and free fatty acids and sparingly degummed phospholipids are produced.

On the other hand, in the production method of the present invention, high temperature cooking is performed before the tissue destruction of seeds. That is, the enzyme in the seed is inactivated by heating at high temperature in advance, and then the seed tissue is destroyed. Therefore, even if the enzyme is contacted with the oil component due to tissue destruction and the temperature is further raised to the enzyme activation temperature, the enzyme is already deactivated, and the oil component is no longer hydrolyzed, and thus the free component is released. It does not produce fatty acids or hard-to-gum phospholipids.

[0017]

(Example) (Example 1) Rapeseed seeds (canola, water content 8.0% by weight) were put into a cooker equipped with stirring blades and an indirect heating jacket with steam as they were as round grains.
After heating at 0 ° C for 5 minutes, the mixture was supplied to the twin-screw press described in JP-A-2-251397 to obtain compressed oil and pressed cake.

The pressed cake was mixed with 3 times the weight of hexane to obtain 60
Extraction was performed at 30 ° C. for 30 minutes, and this operation was repeated 3 times. Hexane containing oil was all combined and distilled to distill off hexane to obtain an extracted oil. After the hexane was completely removed by air-drying the extracted lees, the water content was adjusted to 20% by weight and heat-treated at 100 ° C for 30 minutes.

The pressed oil and the extracted oil were combined (crude crude oil), and 2% by weight of water and 0.05% by weight of phosphoric acid were added to the mixture to give 70
The mixture was stirred at 0 ° C. for 20 minutes and centrifuged to remove gum. To this degummed oil, add caustic soda and phosphoric acid to deoxidize,
The generated soda oil layer was centrifuged. 10% by weight of hot water
Was added, and the mixture was stirred at 80 ° C. for 1 minute and centrifuged. To a mixture of soda oil layer and hot water wash water, add concentrated sulfuric acid to pH 1
And heated at 100 ° C. for 4 hours to float the deoxidized oil. The COD (chemical oxygen demand) of the water layer was measured. Add 1.5% by weight of activated clay to deoxidized oil and add 3 at 80 ℃
Stirred under vacuum for 0 min and filtered to give a decolorized oil. This decolorized oil was deodorized by heating at 250 ° C according to a conventional method to obtain a purified oil.

The acid value and P content of the above crude crude oil and degummed oil,
Table 1 shows the yield of oil obtained in each step, the COD value, and the glucosylate content in the pressed meal.

(Comparative Example 1) The rapeseed seeds were flattened at 105 ° C for 5
Except for feeding the cooked food for 2 minutes to the twin-screw press,
A refined oil was obtained in the same manner as in Example 1. Also, as in Example 1, the yield of each oil and the component analysis results were obtained. The results are shown in Table 1.

(Comparative Example 2) A refined oil was obtained in the same manner as in Example 1 except that heating was performed at 95 ° C for 30 minutes in a cooker. Further, as in Example 1, the yield of each oil and the component analysis result were obtained. The results are shown in Table 1.

[0023]

[Table 1]

(Examples 2 to 14) Crude crude oil and degummed were the same as in Example 1 except that rapeseed seeds having the water content shown in Table 2 were used and the heating conditions in the cooker were as shown in Table 2. Oil and pressed meal were obtained. Table 2 shows the acid value and P content of the obtained crude crude oil and degummed oil, and the glucosylate content in the pressed meal.

[0025]

[Table 2]

Comparative Examples 3 to 15 In the same manner as in Example 1 except that rapeseed seeds having a water content shown in Table 3 were pressed and the heating conditions in the cooker were as shown in Table 3. Crude oil, degummed oil, and pressed meal were obtained. Table 3 shows the acid value and P content of the obtained crude crude oil and degummed oil, and the glucosylate content in the pressed meal.

[0027]

[Table 3]

[0028]

Industrial Applicability According to the production method of the present invention, rapeseed crude oil having a low acid value and easy to be degummed can be obtained. as a result,
Crude oil refining is very easy and the yield of refined oil is improved. In addition, the pollution load of waste water is extremely low, which is very favorable for the environment. Furthermore, the pressed cake after oil extraction has a low glucosinolate content and is excellent in quality, and is therefore optimal as a feed raw material.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Teruo Ishida 230 Shinko, Mihama-ku, Chiba, Chiba Toyo Oil Co., Ltd.

Claims (2)

[Claims] 1. A method for producing rapeseed oil, which comprises heating rapeseed seeds having a water content of 5 to 20% by weight in the form of round grains at 101 to 150 ° C. for 1 to 120 minutes, and then destroying the tissue of the rapeseed oil. 2. The method for producing rapeseed oil according to claim 1, comprising a step of squeezing with a biaxial squeezing machine after heating.