JPH0457853A - Method for extracting and separating coloring matter from krill - Google Patents

Abstract

PURPOSE:To prepare a reddish orange coloring matter having a high safety in a high concn. by extracting, with CO2 in a supercritical state, krill shells of which the protein has been decomposed by a protease. CONSTITUTION:Krill shells are treated with a protease to decompose the protein in the shells and the treatment product is filtered. The residue of filtration is dried to give treated shells having a water content of 6-8% and a mean particle size of 200 mum or lower. The treated shells are put into an extraction vessel 5. An extractant comprising a liq. CO2 in an amt. of 30-40 pts.wt. based on one pt.wt. treated shells having a coloring matter concn. of 30 mg/100 g is supplied through a supercooling apparatus 2 to a pump 3, pressurized at the pump 3 to 100-250 kg/cm<2>, heated with a heat exchanger 4 to 35-40 deg.C to bring it into a supercritical state, and transferred to the extraction vessel 5 to extract an oil in the treated shells. After the pressure of the oil-contg. CO2 in the supercritical state is reduced to 40-60 kg/cm<2> with a pressure reducing valve 6, the CO2 is delivered through a selector valve 11 to the first separating vessel 7 to separate the oil, and recycled through a selector valve 13, a pressure reducing valve 9, a condense 10, a water separator 15, and a storage vessel 1 to the extraction vessel 5. Then, selector valves 11 and 13 are closed while selector valves 12 and 14 are opened, and the CO2 contg. the coloring matter is transferred to the second separating vessel 8, where the CO2 is evaporated to give a coloring matter with a concn. of 2000-10000 mg/100g.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a method of separating a reddish-orange pigment containing astaxanthin as the main component contained in krill to obtain a highly concentrated pigment. This invention relates to a method of extraction and separation using carbon dioxide.

[Prior Art] A reddish-orange pigment containing astaxanthin as a main component contained in krill is generally extracted from living krill using an organic solvent. This extract contains various components including fats contained in krill. In particular, oxidative decomposition products such as unsaturated fatty acids and their glycerin esters that are interposed or bonded to pigments may emit a strange odor, or reaction products in the process of oxidative decomposition of unsaturated fatty acids can cause discoloration of pigments. It is necessary to concentrate and separate only the pigments contained in this pigment extract.

For methods of concentrating and separating pigments from krill pigment extracts, see, for example, JP-A-60-4558 or JP-B-61-52183.
After adjusting the pH of the krill pigment extract extracted with an organic solvent such as hexane or acetone to neutrality, a solution prepared by adding lipase to decompose lipids or alkali to decompose lipids or other impurities. It has been proposed to separate a dye liquid and then extract and separate this dye liquid using a molecular distillation region or a fluid in a supercritical state.

[Problems to be solved by the invention] Conventionally proposed methods for concentrating and separating krill pigments:
Extraction process of krill pigment liquid from the living body of krill using an organic solvent, neutralization process, decomposition process of lipids and impurities using linoxase or alkali, separation process of the decomposition products of impurities and krill pigment, molecular distillation process, A number of steps are required, including extraction steps with supercritical fluids.

In addition, it has been reported that the red-orange pigment contained in krill, whose main component is astaxanthin, has an antioxidant effect that is 100 to 1000 times stronger than vitamin E, and is expected to be used as a pharmaceutical raw material in the future. When used as a pharmaceutical raw material, a process such as desolvation is required to completely prevent the organic solvent used in the extraction process of the krill pigment liquid from remaining.

It is also possible to directly extract krill that has not undergone any processing steps using carbon dioxide in a supercritical state, but since a large amount of water and various useful components contained in krill are extracted at the same time, only pigments are extracted. It was difficult to concentrate and separate.

[Means for Solving the Problems] The present inventors have conducted extensive research to solve the above-mentioned problems, and have come up with the present invention.

Krill is used as a raw material for processed foods because it contains many useful components such as protein.

Among these uses, instead of using krill as it is, the tannolyte contained in krill is separated and used as a raw material for amino acids. Traditionally, krill shells that have been used for harvesting have been either discarded or used as feed for farmed fish.

The present inventors have extracted the liquid pigment from krill using a fluid in a supercritical state by using the remaining shells after extracting components such as tannin from krill as a raw material for producing pigment. We have discovered that it is possible to produce krill pigments without special pretreatment steps by adopting a simple method.

That is, the method uses krill shells, which are the residue obtained by filtration after decomposing useful components such as tannin in krill with enzymes, as a raw material, and extracts pigments using a supercritical fluid.

In the present invention, a fluid in a supercritical state is a fluid in a state in which the critical temperature and pressure are exceeded, and in the case of carbon dioxide, the temperature is 31°C or higher and 75.3 kg/cm2 or higher, and in the case of propane, the fluid is 96.7°C or higher and 43. 4Kg/cm2 or more,
For ethylene, 9.9℃ or higher, 52.2K g/c
Refers to something that is in a state of m2 or more. These fluids are characterized by having a density close to that of a liquid and a diffusion constant close to that of a gas, and are used for extraction and separation of various organic substances. In particular, the method of the present invention uses carbon diacid as the fluid in a supercritical state.
The use of carbon dioxide not only simplifies the steps required to extract and separate the pigment, but also the carbon dioxide used as an extractant, even if it remains in the extracted pigment, can be dangerous. There is no problem at all, and the obtained dye can be used without problems in many fields including the pharmaceutical field.

Furthermore, supercritical carbon dioxide used as an extractant is
Unlike hydrocarbons, there is no risk of explosion or combustion in the air. In addition, since carbon dioxide has a relatively low critical temperature and critical pressure, its solubility characteristics can be easily changed by changing the temperature and pressure, and the solubility characteristics are suitable for extracting and separating pigments. Extraction can be performed with an extractant.

The method of the present invention extracts pigments using carbon dioxide in a supercritical state using krillic acid as a raw material. At this time, extraction pressure, temperature, fractionation method, etc. are necessary for efficient extraction and separation of pigments. After studying the extraction conditions and the water content of the raw material krill acid, the method of the present invention was completed.

The present invention will be described below with reference to the drawings.

FIG. 1 shows a flow sheet of an apparatus having switching means for a plurality of separation tanks for carrying out the method of the present invention.

Carbon dioxide, which is an extractant, passes through a supercooler 2 from a liquid carbon dioxide storage tank 1 and is pressurized to a predetermined pressure by a pump 3.Next, it is heated to a predetermined temperature in a heat exchanger 4, and becomes supercritical. The carbon dioxide is supplied to the extraction tank 5 filled with krillic acid.

The raw material, krill acid, mainly contains chitin, protein, triglyceride ester, diglyceride ester, monoglyceride ester (oil), and pigment (astaxanthin). After thawing frozen krill, the extract is obtained by decomposing the protein with proteolytic enzymes. The residue obtained upon filtration is a powder with an average particle size of 200 μm, and when dried, it usually has a moisture content of 6% to 8%.

Carbon dioxide in a supercritical state has the property of dissolving the oil and pigment in krill acid, so only these two components can be extracted from krill acid, but in order to separate these two components, the extraction operation is performed in two stages. It is done separately.

That is, the first stage of extraction is carried out at a temperature of 35°C to 50°C and at a relatively low pressure of 100 K for 1 part by weight of krill shells with a pigment concentration of 30 mg/100 g, which corresponds to the concentration of astaxanthin contained. g/cm
The oil contained in the krill acid is extracted using 30 to 40 parts by weight of supercritical carbon dioxide at 2 to 250 kg/cm 2 .

The supercritical carbon dioxide containing oil is reduced to a pressure of 40 kg/cm2 to 60 kg by the pressure reducing valve 6.
The pressure is reduced to /cm2, and the liquid is guided to the first separation tank 7 through the switching valve 11.

The gaseous carbon dioxide from which the oil has been separated in the first separation tank 7 is further reduced in pressure by the switching valve 13 and the pressure reducing valve 9, expands adiabatically, is liquefied in the condenser 10, and then passes through the water separator 15 to form a liquid. It is returned to the carbon dioxide storage tank 1 and used for circulation.

Subsequently, carbon dioxide in a supercritical state is supplied to the extraction tank 5 at a relatively higher pressure than the pressure during the first stage extraction. That is, supercritical carbon dioxide is supplied to the extraction tank at a temperature of 30°C to 50°C and a pressure of 300 kg.
/cm2 to 500Kg/cm2, 30 to 40 parts by weight per 1 part by weight of krill shells, closed switching valves 11 and 13, opening switching valves 12 and 14, and applying 40 K by pressure reducing valve 6. g/c
The carbon dioxide containing the extract at m 2 to 60 K g/cm 2 is led to a second separation tank 8 . The carbon dioxide that has become a gas in the second separation tank 8 is returned to the liquid carbon dioxide storage tank 1 in the same manner as in the first stage extraction process.
The dye concentration from the second separation tank 8 is 2,000 mg/100
A dye with a very high dye density of 10 g to 10 g, OOO mg/+00 g is obtained.

As described above, pigments with high pigment concentration can be obtained by continuously performing the two-stage extraction of low pressure and high pressure, but efficient collection is possible by providing multiple separation tanks and switching between the separation tanks. It is.

Moreover, it is also possible to perform similar extraction and separation at the same pressure, without performing the two-stage extraction by changing the pressure as described above.

That is, it is also possible to extract and separate highly concentrated pigments by the extraction operation shown in FIG. Referring to FIG. 2, carbon dioxide from the liquid carbon dioxide storage tank 1 is sent to the pump 3 through the supercooler 2 and pressurized to a predetermined pressure. Subsequently, it is heated to a predetermined temperature in a heat exchanger 4, and then supplied to an extraction tank 5 filled with krill acid in advance.

1 part by weight of krill shell (pigment concentration 30 mg/10
0g), 30 parts by weight to 50 parts by weight at a temperature of 3
5℃ to 50℃, pressure 300Kg/cm2 to 5
00 K g/cm 2 of supercritical carbon diacid. In the extraction tank, in the early stage of extraction, high concentration of pigment is extracted.The supercritical carbon dioxide containing the extract is reduced to 40 K with pressure reducing valve 6.
g/cm 2 to 60 K g/cm
2 and is led to the first separation tank 7.

The carbon dioxide discharged from the first separation tank is further reduced in pressure by the pressure reducing valve 9 and liquefied by the LM condenser 10, and then returned to the liquid carbon dioxide storage tank 1 via the water separator 15.

This extraction method uses carbon dioxide in a relatively high-pressure supercritical state from the beginning of the extraction, so the pigment is extracted along with the oil. After extraction is performed by supplying 15 to 25 parts by weight of carbon dioxide, the first separation tank 7
The extract mainly consisting of oil is separated from the soot extracting valve 16 provided at the lower part of the extractor. Subsequently, by supplying 15 to 25 parts by weight of carbon dioxide in a supercritical state per 1 part by weight of krill shells, a dye concentrate is obtained in the first separation tank.

The pigment concentration in the oil obtained by this method is 10mg/1
00g to 30 mg/100g, and the dye concentration in the dye concentrate was 2,000mg/loOg to 10,000mg/100g.

In this method, since relatively high-pressure supercritical carbon dioxide is used from the early stage of extraction, some pigment is contained in the oil that is the initial extract. This method has the characteristic that the extraction time can be shortened compared to the method using carbon dioxide in a supercritical state.

Further, FIG. 3 shows a method in which a plurality of separation tanks are continuously provided and the separation conditions are changed by changing the set pressure and temperature of each separation tank to efficiently recover the dye.

This will be explained below with reference to FIG.

Carbon dioxide is sent from liquid carbon dioxide storage tank 1 to pump 3 through supercooler 2 and pressurized to a predetermined pressure.

Thereafter, it is heated to a predetermined temperature in a heat exchanger 4 to reach a supercritical state, and is then supplied to an extraction tank 5 filled with krill shells in advance.

Here, the supercritical carbon dioxide supplied to the extraction tank 5 has a temperature of 35°C to 50'C and a pressure of 300 kg/c.
m2 to 500Kg/cm2.

Oil and pigments are extracted from the krill shells in the extraction tank. This supercritical carbon dioxide containing oil and pigments is depressurized by a pressure reducing valve 6 and guided to a high-pressure separation tank 17.

The high-pressure separation tank 17 is maintained in a supercritical state at a temperature of 35° C. to 50° C. and a pressure of 100 K g/cm 2 to 300 K g/cm 2, which is lower than the inside of the extraction tank. The supercritical carbon dioxide containing oil is depressurized by the pressure reducing valve 18 and guided to the low pressure separation tank 19.

The low pressure separation tank 17 has a temperature of 20°C to 30'C and a pressure of 40°C.
K g/c m2 to 60 K g/c
M2 The tag is kept in a gas state. Oil will not be collected in the tank.
The pressure of the carbon dioxide is further reduced by a pressure reducing valve 9, liquefied by a condenser 10, water contained therein is removed by a water separator 15, and then returned to the liquid carbon dioxide storage tank 1.

Using this method, 1 part by weight of krill shell (pigment concentration 30
mg/100g), relatively high pressure 300Kg/
By passing 30 parts by weight to 40 parts by weight of carbon dioxide in a supercritical state of cm2 to 500 kg/cm2, it is possible to obtain a dye having a dye concentration of 2,000 mg/7100 g/loog to 10,000 mg/looog,
An oil with a low pigment concentration can be obtained as an extract in the low-pressure separation tank.

Initially, the pressure of supercritical carbon dioxide supplied to the extraction tank was changed to relatively low pressure supercritical carbon dioxide below 300 K g/cm2, and later to relatively high pressure supercritical carbon dioxide. The method of supplying carbon dioxide yields a large amount of pigment, since almost no pigment is extracted in the initial extract, but it takes a long time for extraction; on the other hand, it requires relatively high pressure of 300 K g/cm2 or 500K
The method of separating extracts over time using g/cm2 of supercritical carbon dioxide to initially extract the oil and then extract the pigment concentrate has a simple equipment configuration. Although the extraction time is short, there is a problem that the amount of pigment obtained is reduced because some pigment is contained in the oil obtained as the initial extract.
The method shown in the figure in which multiple separation tanks with different pressures and temperatures are provided to continuously obtain extracts of components under different extraction conditions is superior to the above two methods.

In addition, rillic acid (
The pigment concentration of 30 mg/]OOg) is relatively high because it is possible to accelerate the extraction rate, especially the initial extraction rate, by increasing the water content of krillic acid to 10% to 30% by weight. 300 Kg of high pressure
It is possible to reduce the amount of pigments contained in the oil extract obtained at the initial stage of extraction using carbon dioxide in a supercritical state of /cm2 to 500Kg/Cm2. It is possible to prevent a decrease in the amount of dye that is lost.

Due to the addition of water, the water is extracted along with the pigment, but
Since water and the pigment can be easily separated into two layers, the addition of water does not pose any obstacle to the extraction and separation of the pigment.

However, if the water content exceeds 30%, the extraction rate at the initial stage of extraction will decrease, so it is not preferable to increase the amount of water above 30%.

The water content of krill acid is preferably adjusted by controlling the drying state during the krill treatment process.
When using dry krill acid with a relatively low water content, it is necessary to sprinkle water on the krill acid before the extraction step and then thoroughly mix it.

[Function] When producing a pigment made from astaxanthin contained in krill, the present invention uses the remaining shells from which components such as proteins have been collected from krill using a proteolytic enzyme as a raw material for producing the pigment, and processes it in a supercritical state. The krill pigment is extracted using carbon dioxide as an extractant, and it is possible to produce krill pigment without going through a special pretreatment process using an organic solvent.

[Example] Examples of the present invention will be shown below to explain the present invention in more detail.

Example 1 Using protease as a proteolytic enzyme, frozen krill was thawed and subjected to a proteolytic reaction at 47°C to 48°C for 2 hours.The liquid was filtered and the separated residue was dried to produce krill with a water content of 6%. Obtained acid. This krillic acid (
Dye concentration 30 mg 7100g) 6Kg in volume 25
Fill a small extraction tank, keep the temperature of the extraction tank at 40℃, temperature 40'C1 pressure 200K g / cm
2 supercritical carbon dioxide was supplied at a supply rate of 60 Kg per hour for 4 hours, and the pressure was 50 Kg/crn2.
Carbon dioxide and liquid are separated in a separation tank at a temperature of 30°C, and the dye concentration is 7.1 from the extraction valve at the bottom of the separation tank.
1398 g of mg/100 g extract was obtained.

Furthermore, the temperature in the extraction tank is 40℃ and the pressure is 400Kg/Cm2.
Supercritical carbon dioxide was supplied for 4 hours at a supply rate of 60 kg/hour, and the pressure in the separation tank was set to 50 kg/cm2.
, the dye concentration was 83 from the residue of the previous extraction at a temperature of 30°C.
13.4 g of a highly concentrated dye of 31 mg/100 g was obtained.

Example 2 Krillic acid (with the same components as those used as raw materials in Example 1)
Fill an extraction tank with a volume of 25 liters with 6 kg (pigment concentration 30 mg/100 g), maintain the temperature of the extraction tank at 40°C,
Carbon dioxide in a supercritical state at a temperature of 40'C and a pressure of 400Kg/cm" was supplied at a supply rate of 60Kg per hour for 2 hours, and the pressure was set at 50Kg/cm2 and the temperature was 30C from the extraction valve at the bottom of the separation tank. The extract was taken out to obtain 1703 g of an extract with a pigment concentration of 42.8 mg/100 g.

Furthermore, the temperature is 40℃ and the pressure is 400K in the extraction tank.
g/cm2 of supercritical carbon dioxide was supplied at a rate of 60 kg per hour for 5 hours from the start of extraction, and the dye concentration reached a high pigment concentration of 5874 mg/100 g in a separation tank with a pressure of 50 kg/cm2 and a temperature of 30°C. The density of the dye Log was obtained.

Example 3 Krill shells (with the same ingredients as those used as raw materials in Example 1)
Pigment concentration: 30 mg/100 g) 250 g was packed into an extraction tank with a volume of 1 liter, the temperature of the extraction tank was maintained at 40°C, and carbon dioxide in a supercritical state at a temperature of 40'C and a pressure of 400 Kg/Cm2 was added per hour. The carbon dioxide in a supercritical state containing the extract obtained in the extraction tank was supplied to a high-pressure separation tank maintained in a supercritical state.

The high pressure separation tank has a temperature of 40'C and a pressure of 250 Kg/
cm2, and the extract in the low pressure separation tank was fed via a pressure reducing valve to the low pressure separation tank maintained at 60 K g/cm2 at 20 °C.

As a result, the dye concentration from the high-pressure separation tank was 7072 mg.
/ 0.44g of 100g of pigment can be obtained.

The dye concentration from the low-pressure separation tank is 6.2'mg/l0.
70.57 g of 0 g of dye was obtained.

Example 4 Krill shell 6K with the same ingredients as those used in Example 1
After spraying water on the mixture, the mixture was sufficiently mixed to change the water content of Ml, and the pigment was extracted and separated.

Krill shells with different moisture contents were filled into an extraction tank with a volume of 25 liters, and the temperature of the extraction tank was maintained at 40°C.
c, supplying supercritical carbon dioxide at a pressure of 400 K g/cm2, and increasing the pressure to 50 K g/cm2.
2. Separated in a separation tank at a temperature of 30°C, the amount of oil fraction obtained from the start of extraction, the amount of pigment obtained after oil fractionation and extraction time are shown in Table 1. show.

[Margin below] Table 1 It is possible to extract and separate dark pigments.

[Brief explanation of drawings]

FIG. 1 shows a flow sheet of an extraction device for switching between multiple separation vessels used to carry out the method of the invention, and FIG. FIG. 3 shows a flow sheet of an apparatus having separation vessels with different pressures used to carry out the method of the present invention. [Effect of the invention] The present invention extracts reddish-orange pigments containing astaxanthin from krill shells using supercritical carbon dioxide. Conventionally, useful components were collected from krill and treated as waste. It effectively uses krill shells as a raw material, and since it does not use organic solvents, it is a simple process that does not require an organic solvent separation process, and is highly safe in the food and pharmaceutical fields. Liquid carbon dioxide storage tank...1, supercooler...2, pump...3, heat exchanger...4, extraction tank...5, pressure reducing valve...6, first separation tank... ...7.Second separation tank...
8, Pressure reducing valve...9, Condenser...10, Switching valve...
11, 12, 13, 14, water separator...15, extraction valve...16. High pressure separation tank...17, pressure reducing valve...
18. Low pressure separation tank...19 Patent applicant Chlorin Engineers Co., Ltd. (1 other person)

Claims (5)

[Claims] (1) In the method of extracting and separating the pigments contained in krill, krill shells, which are the residues obtained by decomposing krill with proteolytic enzymes and removing proteins, are used as the raw material, and the pigments are extracted using carbon dioxide in a supercritical state as an extractant. A method for extracting and separating pigments from krill. (2) The method for extracting and separating pigments from krill according to claim 1, wherein the extraction and separation involves changing the pressure of supercritical carbon dioxide in two stages to fractionate the extract of krill shells. (3) The method for extracting and separating pigments from krill according to claim 1, wherein the extraction and separation is carried out by separating the extract over time without changing the pressure of carbon dioxide in a supercritical state. (4) The method for extracting and separating pigments from krill according to claim 1, wherein the extraction and separation comprises fractionating the components extracted in the extraction tank using a plurality of separation tanks having different conditions. (5) Moisture content of krill shell is 10% to 30%
Any one of claims 1 to 4, characterized in that
A method for extracting and separating pigments from krill as described in .