JP5532480B2 - Liquid composition containing aromatic components derived from roasted coffee beans, solids, food and drink, and method for producing liquid composition - Google Patents

Description

  The present invention relates to a liquid composition containing an aromatic component derived from roasted coffee beans and a method for producing the same.

  Coffee fragrances are used mainly for enhancing the palatability of foods and beverages by using them in foods and beverages to emphasize the flavor or providing variations in flavors. Examples of the coffee fragrance include natural fragrances, synthetic fragrances, and blended fragrances obtained by combining them. In recent years, with the real intention of consumers for food and drink, coffee fragrance used is a natural coffee fragrance that is a liquid containing aroma components derived from roasted coffee beans.

  However, natural coffee fragrances contain a mixture of aromatic components such as chemically unstable nitrogen-containing compounds and sulfur-containing compounds, and these aromatic components have low storage stability in solution. Conventionally, every method has been taken in order to improve the storage stability of aroma components of natural coffee fragrances.

  For example, a method of adding a stabilizer to coffee natural flavor has been proposed. Examples of the stabilizer include organic solvents such as propylene glycol and ethanol, trehalose and vitamin C (see Patent Document 1), and coumarin derivatives (see Patent Document 2).

  Further, as another method for enhancing the storage stability of the aromatic component of the natural coffee fragrance, there is a method of storing the natural coffee fragrance in a refrigerator or freezing. However, if the natural coffee flavor is stored frozen, there is a problem that carbon dioxide derived from roasted coffee beans is released from the frozen natural coffee flavor and expands the volume of the sealed body. A method of suppressing the volume expansion of the sealed body has been proposed (see Patent Document 3).

JP 2001-292721 A JP 2001-136931 A Japanese Patent Application No. 2006-548819

  The method of adding a stabilizer to the natural coffee fragrance may cause the stabilizer to change the properties of the fragrance component in the natural coffee fragrance. For this reason, the natural flavor of coffee natural flavor is impaired, and it tends to be unfavorable by modern consumers who are genuinely oriented.

  Therefore, as a method for enhancing the storage stability of the fragrance component without adding a stabilizer, there is a method of refrigeration or freezing the natural coffee fragrance as it is. Refrigerated storage has a degree to which the storage stability is slightly improved as compared with storage at room temperature. Cryopreservation is storage at a considerably low temperature, which stabilizes aroma components and enables long-term storage of coffee natural flavors.

  However, the freezing preservation of the natural coffee flavor has a problem that carbon dioxide is liberated from the frozen natural coffee flavor and the volume of the sealed body is expanded. This is because when aroma components are extracted from roasted coffee beans, carbon dioxide attached to the roasted coffee beans is taken into the extract, and the carbon dioxide cannot be dissolved during freezing and is released as a gas. When the volume of the sealed body expands, it is necessary to secure a large storage space, which deteriorates transportation efficiency and increases costs in terms of storage and transportation.

  As described above, for the problem that carbon dioxide is liberated during frozen storage, a method has been proposed in which the volume of the sealed body is suppressed by adjusting its pH before freezing the natural coffee flavor. . By setting the pH to 6 to 10, carbon dioxide existing in the natural coffee flavor is ionized and carbon dioxide is prevented from being released as a gas when frozen. However, the method of adjusting the pH before freezing is excellent in terms of storage stability of aroma components, but is not satisfactory in terms of flavor. Although the total amount of the fragrance component itself does not change, there is a possibility that its characteristic changes and a unique flavor different from the original may be produced.

  Accordingly, an object of the present invention is to provide a liquid composition containing a natural flavor component derived from roasted coffee beans as it is without modification and having good transportability during frozen storage.

1st characteristic structure of the liquid composition which concerns on this invention is a liquid composition containing the aromatic component derived from roasted coffee beans, Comprising: Extracting the aromatic component containing 2-methyl furan from roasted coffee beans, The extraction liquid gas separation membrane treatment, vacuum treatment, or by degassing by either permeation vaporization membrane treatment, dissolved carbon dioxide content is less than or equal 600 ppm, and, 10 g as an internal standard in the head space method / When 250 μL of L cyclohexanol aqueous solution was used to measure the peak areas of 2-methylfuran and cyclohexanol, the value of 2-methylfuran / cyclohexanol, which is the peak area ratio of 2-methylfuran to cyclohexanol, The point is that it is 4.48 or more.
[Action and effect]
According to this structure, when it is sealed and stored frozen, volume expansion due to liberation of dissolved carbon dioxide can be suppressed without adjusting its pH. Therefore, space saving at the time of transportation can be achieved, transportation efficiency can be improved, and since there is no need to adjust pH, there is no possibility of modifying the aroma components.
Furthermore, since the liquid composition of the present composition sufficiently includes aroma components derived from roasted coffee beans represented by 2-methylfuran, it is derived from roasted coffee beans by adding the liquid composition of the present structure. Natural flavors can be easily imparted.

The second characteristic configuration of the liquid composition according to the present invention is that the amount of dissolved carbon dioxide is 500 ppm or less.
[Action and effect]
According to this structure, since volume expansion at the time of sealing and cryopreserving can be suppressed further, transportation efficiency can further be improved.

A third characteristic configuration of the liquid composition according to the present invention is that the peak area ratio is 5.67 or more.
[Action and effect]
Since the liquid composition of this structure contains more aromatic components derived from roasted coffee beans, a better flavor can be imparted by adding the liquid composition of this structure.

A fourth characteristic configuration of the liquid composition according to the present invention is that the peak area ratio is 16.2 or less.
[Action and effect]
Since the liquid composition of this configuration contains aroma components derived from roasted coffee beans in an appropriate range that does not include miscellaneous taste due to other components, a better flavor is imparted by adding the liquid composition of this configuration can do.

The characteristic structure of the solid according to the present invention is that the liquid composition according to any one of the first to fourth characteristic structures is frozen and solidified.
[Action and effect]
The solid material of this configuration is less likely to undergo volume expansion when sealed and stored frozen and has good transportability.

The characteristic structure of the food / beverage which concerns on this invention exists in the point containing at least any one of the liquid composition in any one of the said 1st-4th characteristic structure, and the said solid substance.
[Action and effect]
The food / beverage of this structure exhibits the natural flavor derived from roasted coffee beans.

1st characteristic structure of the manufacturing method of the liquid composition which concerns on this invention is a method of manufacturing the liquid composition containing the aromatic component derived from a roasted food raw material, Comprising: The extraction process which extracts an aromatic component, The said extraction process gas separation membrane treatment method resulting extract in vacuum treatment, or by any of the transmission vaporization membrane treatment seen including a degassing step of degassing, the roasted food material is a roasted coffee beans The extraction step of extracting aromatic components containing 2-methylfuran from roasted coffee beans and the extract obtained in the extraction step have an amount of dissolved carbon dioxide of 600 ppm or less and an internal standard in the headspace method. When the peak areas of 2-methylfuran and cyclohexanol were measured using 250 μL of 10 g / L of cyclohexanol as a substance, There a value of 2-methylfuran / cyclohexanol with a peak area ratio of the furan to a point comprising said degassing step to 4.48 or more.
[Action and effect]
According to this configuration, the natural flavor component derived from the roasted food material is included as it is without modification, and the volume expansion due to the liberation of dissolved carbon dioxide when sealed and stored in a frozen state is suppressed. A liquid composition with good properties can be produced.
Moreover, especially by performing a deaeration process by a gas separation membrane processing method, a dissolved carbon dioxide can be selectively removed, without impairing an aromatic component.
In addition, according to the present configuration, the natural flavor component derived from roasted coffee beans is included as it is without modification, and volume expansion due to liberation of dissolved carbon dioxide when sealed and stored frozen is suppressed. A liquid composition having good transportability can be produced .

The 2nd characteristic structure of the manufacturing method of the liquid composition which concerns on this invention exists in the point which performs the said extraction process by the gas-liquid countercurrent contact extraction method.

[Action and effect]
By performing the extraction step by the gas-liquid countercurrent contact extraction method, it is possible to more efficiently extract aroma components derived from roasted coffee beans.

Diagram showing the relationship between the amount of dissolved carbon dioxide in the extract and the volume expansion coefficient The figure which shows the relationship between a deaeration process and the remaining aromatic component (2-methyl furan). The figure which shows the influence of the liquid temperature of the extract in the gas separation membrane processing method

Embodiments of the present invention will be described below.
(Liquid composition)
The liquid composition according to the present invention is a liquid composition containing water as a main solvent, and contains an aromatic component derived from roasted coffee beans. It is said that there are about 800 types of aroma components derived from roasted coffee beans, and many components related to coffee taste and aroma improvement are known. For example, as an aroma component of coffee, aldehydes, esters, furans, ketones, alcohols, pyrazines, pyrroles, pyridines, sulfur compounds, etc. are known, and 2-methylfuran (2-methylfuran) is known. Is a particularly representative aroma component among aroma components derived from roasted coffee beans.

When the liquid composition according to the present invention measured the peak areas of 2-methylfuran and cyclohexanol using 250 μL of 10 g / L aqueous cyclohexanol as an internal standard substance in the headspace method, 2-methylfuran is contained in such an amount that the value (A) of 2-methylfuran / cyclohexanol, which is the peak area ratio of methylfuran, is 3.58 or more, more preferably 5.67 or more.
The peak area ratio value (A) is preferably 3.58 ≦ (A) ≦ 16.2, and more preferably 5.67 ≦ (A) ≦ 16.2.

  In addition, the liquid composition which concerns on this invention contains various aromatic components other than 2-methyl furan. That is, 2-methylfuran has a meaning as an index component of the fragrance component contained in the liquid composition according to the present invention, and it is determined that the larger the amount of 2-methylfuran, the higher the content of the fragrance component. Is done.

Specific examples of the method for measuring 2-methylfuran by the headspace method are shown below.
Into a 20 mL headspace vial, take 2.5 mL of the sample and 7.25 mL of 0.17 M disodium hydrogenphosphate (Nacalai Tesque) -4.0 M sodium chloride (Nacalai Tesque) aqueous solution, and use the internal standard. As a substance, 250 μL of a 10 g / L aqueous solution of cyclohexanol (manufactured by Nacalai Tesque) is added, sealed, and held at 40 ° C. for 10 minutes, and a sample is introduced into the gas chromatography using a headspace sampler. Detailed conditions are as follows.

Sampling device: Headspace sampler (manufactured by Agilent: 2.5 mL syringe)
Analytical apparatus: gas chromatography (manufactured by Agilent: GC: 6890/5973 GC-MSD)
Column: ULTRA2 (manufactured by Agilent: 50 m (length) × 0.32 mm (inner diameter) × 0.52 μm (film thickness))
Temperature conditions: 40 ° C (5 minutes hold), 40 ° C-60 ° C (4 ° C / min), 60 ° C-200 ° C (10 ° C / min)
Sample pretreatment conditions: 40 ° C., 10 minutes, 500 rpm
Sample introduction conditions: inlet temperature 200 ° C., split 25: 1
Sample introduction amount: 500 μL
Gas flow rate: Helium 2.0mL / min
Mass range: 30-600 (total ions)
Scan speed: 2.58 / sec
Ionization voltage: 69.9
MS ion source 230 ° C Quadrupole 150 ° C

  Moreover, the amount of dissolved carbon dioxide of the liquid composition according to the present invention is 1000 ppm or less, more preferably 500 ppm or less.

The specific example of the measuring method of the amount of dissolved carbon dioxide is shown below.
The pH of the sample is adjusted to 11 with sodium hydroxide solution, and dissolved carbon dioxide is converted to Na ₂ CO ₃ and NaHCO ₃ to H ₂ CO ₃ . Next, the amount of H ₂ CO ₃ contained in the sample is measured using high performance liquid chromatography. In other words, the amount of dissolved carbon dioxide contained in the sample is indirectly quantified by measuring the amount of H ₂ CO ₃ .
The conditions for high performance liquid chromatography are shown below. The quantification is performed using a calibration curve prepared in advance using an aqueous sodium hydrogen carbonate solution (dissolved carbon dioxide concentration of 1000 ppm).
Equipment used: Organic acid analysis system (manufactured by Shimadzu Corporation)
Column used: Column name for analysis of hydrophilic compounds (Shimadzu Corporation: SPR-H)
Column temperature: 40 ° C
Analysis time: 18 minutes Mobile phase: 4 mM p-toluenesulfonic acid (Nacalai Tesque) aqueous solution Buffer: 4 mM p-toluenesulfonic acid aqueous solution (Nacalai Tesque) and 78 μM EDTA (Wako Pure Chemical Industries) Mixed solution with 16 mM Bis-Tris (manufactured by Nacalai Tesque) solution containing: Mobile phase flow rate: 0.8 mL / min Buffer flow rate: 0.8 mL / min Detector: Conductivity meter (manufactured by Shimadzu Corporation)

(Method for producing liquid composition)
The method for producing the liquid composition includes an extraction step of extracting aroma components containing 2-methylfuran from roasted coffee beans, and degassing the extract obtained in the extraction step so that the amount of dissolved carbon dioxide is 1000 ppm or less. In addition, when the peak areas of the internal standard substances cyclohexanol and 2-methylfuran were measured by the headspace method, the peak area ratio of 2-methylfuran to cyclohexanol was 2-methylfuran / cyclohexanol. And a degassing step of maintaining the value of 3.58 or more.

(1) Extraction Step As a treatment method applicable to the extraction step, for example, a known method such as a steam distillation method or a gas-liquid countercurrent contact extraction method can be applied.

  The steam distillation method is a method in which water vapor is passed through a raw material, and an aromatic component distilled off accompanying the water vapor is condensed together with water vapor. As required, any distillation technique of pressurized steam distillation, atmospheric steam distillation, and reduced pressure steam distillation can be employed. Specifically, for example, steam is blown from the bottom of a steam distillation kettle charged with roasted coffee beans, and the distilled steam is cooled by a cooler connected to the upper distillation side. Thereby, the extract containing a volatile aromatic component as a condensate is collected. If necessary, a volatile aroma component having a lower boiling point can be reliably collected by connecting a cold trap using a refrigerant to the end of the aroma component collecting device.

  The gas-liquid countercurrent contact extraction method can be carried out by various known methods. For example, a method of extraction using an apparatus described in Japanese Examined Patent Publication No. 61-274705 can be employed. A means for recovering aroma components using this apparatus will be specifically described. First, a liquid or paste material mixed with roasted coffee beans and water flows down from the top onto the rotating cone of a gas-liquid countercurrent contact extraction device having a structure in which rotating cones and fixed cones are alternately combined. Let And if a vapor | steam is raised from the lower part, the aromatic component derived from a roasted coffee bean can be collect | recovered. Although the operating conditions of this gas-liquid countercurrent contact extraction apparatus can be selected arbitrarily, a specific example is shown below.

Raw material supply speed: 300 to 700 L / Hr
Steam flow rate: 5-50Kg / Hr
Evaporation amount: 3-35Kg / Hr
Column bottom temperature: 40-100 ° C
Column top temperature: 40-100 ° C
Degree of vacuum: atmospheric pressure to -100Kpa

  The roasted coffee beans can be used as they are, but after being subjected to a pretreatment such as pulverization, and then subjected to an extraction step, distillation of aroma components is further promoted and effective.

(2) Deaeration process As a treatment method applicable to the deaeration process, for example, a known method such as a gas separation membrane treatment method, a heating treatment method, a reduced pressure treatment method, a pervaporation membrane treatment method, or an air blowing method is applied. can do.

  The gas separation membrane treatment method is a method of selectively permeating and separating a specific gas through a gas separation membrane. In the present embodiment, the extract obtained in the extraction step is applied to a gas separation membrane, and carbon dioxide is selectively removed while leaving an aroma component.

  The gas separation membrane applicable to the present invention is not limited as long as it can selectively permeate and separate carbon dioxide, and a generally known deaeration membrane may be used. A deaeration membrane is generally defined as a membrane that allows gas to pass but not liquid, but for the present invention, it is easy to pass carbon dioxide under certain degassing conditions. It is defined as a membrane that is difficult to pass. There are two types of membranes, a non-porous membrane and a porous membrane. However, in principle, the gas dissolved in water is the same because the gas concentration between the inside and outside of the membrane is removed using the driving force.

  The porous membrane has a feature that prevents the liquid from entering the gas phase side by utilizing the hydrophobic property of the membrane when the liquid has a high surface tension. As long as carbon dioxide can be separated, the pore size is not particularly limited, but the pore size of the gas separation membrane is preferably 0.03 μm to 0.04 μm.

  The non-porous film has no pores, so the gas-liquid contact is slightly lowered, but there is an advantage in that there is no problem that the solution enters the gas phase side in the case of a liquid having a low surface tension. In any case, the above-described film may be appropriately selected as necessary.

  The membrane area of the gas separation membrane, the pore area ratio (in the case of a non-porous membrane, it is expressed as the ratio of the membrane area where gas-liquid exchange can occur with respect to the entire membrane area), and the liquid flow rate depends on the gas-liquid contact efficiency. It affects the degree of deaeration. In general, the gas-liquid contact efficiency is represented by a value obtained by dividing the membrane area by the pore area ratio and dividing by the liquid flow rate. As can be seen from this relational expression, when the membrane area and the pore area ratio become large under the condition of a constant flow rate, gas-liquid exchange is likely to occur, and conversely, under the condition where the membrane area and the pore area ratio are constant. As the liquid flow rate increases, gas-liquid exchange is less likely to occur. For this reason, the present invention is not limited to the above-described factors, and the gas-liquid contact efficiency is adjusted by changing any of the membrane area, the hole area ratio, and the liquid flow rate.

In order to cause a difference in gas concentration between the inside and outside of the membrane, a gas containing as little gas (carbon dioxide) as possible to be degassed and removed is passed through one space across the membrane, or the gas phase side is evacuated. The method is effective. In the present invention, if necessary, the kind of gas (air, nitrogen, argon, helium, etc.), the flow rate of gas, and the degree of vacuum are appropriately adjusted so that the carbon dioxide concentration difference can be made between the inside and outside of the membrane. Good. In addition, if the gas-liquid contact efficiency is changed, the same quality can be obtained by changing the gas concentration difference between the inside and outside of the membrane. Instead of having a fixed value, it is necessary to adjust each balance.
As long as the liquid composition can be prepared, there are no restrictions on conditions such as gas-liquid contact efficiency and gas-liquid flow rate ratio, but preferably the gas-liquid contact efficiency is 0.001 m / min and the gas-liquid flow rate ratio is 0.00. 2 to 5.0. When the temperature of the sample solution is low, the solubility of dissolved carbon dioxide increases and the degassing strength may decrease. In this case, the gas-liquid flow rate ratio may be increased.

  The heating treatment method is a method of heating and degassing the sample solution, and the principle is the same as that of steam blowing, which is one of the stripping operations. The solubility of gas varies depending on the temperature of the sample solution. It is used. In the present embodiment, the extracted liquid is heated with appropriate stirring to degas dissolved carbon dioxide. As long as the liquid composition can be prepared, there are no restrictions on conditions such as the apparatus used, temperature, and stirring speed, but preferably the temperature is 50 ° C. and the treatment time is 15 minutes.

  The reduced pressure treatment method is a method for performing deaeration treatment by placing a sample liquid under reduced pressure. In the present embodiment, vacuum deaeration is performed on the extract using a vacuum pump. If the liquid composition can be prepared, the conditions such as the degree of vacuum, the apparatus, the temperature, and the stirring speed are not limited. However, preferably, the degree of vacuum is 100 hpa to 800 hpa, the processing temperature is 10 ° C., and the stirring speed is 130 rpm. And

  The pervaporation membrane treatment method is also called pervaporation, and is a method of evaporating liquid through a membrane. In the present embodiment, the extracted liquid is subjected to a polymer film having no pores or an inorganic film having molecular pores to separate dissolved carbon dioxide from the extracted liquid. There are no particular limitations as long as the liquid composition can be prepared, but preferred operating conditions include a vacuum degree of 0 hpa and a treatment liquid temperature of 55 ° C. to 60 ° C. Is vacuumed. It is preferable to change the membrane area of the pervaporation membrane and the treatment time depending on the treatment amount.

  The air blowing method is one of stripping operations, and is a method in which an appropriate gas is passed through a sample liquid to perform a deaeration process (for example, aeration using nitrogen when performing deoxygenation) And the principle is the same). In the present embodiment, a predetermined gas is passed through the extract to degas dissolved carbon dioxide. As long as the liquid composition can be adjusted, there are no particular restrictions on the type of gas to be vented, the flow rate, the apparatus, the temperature, and the like. However, as a preferable condition, air is supplied at a temperature as low as about 10 ° C. The amount is adjusted to 5 L / min.

Below, the use etc. of the liquid composition which concerns on this invention are demonstrated.
The storage temperature of the liquid composition may be appropriately set depending on the storage period and the like, but it is desirable to store it by freezing and solidifying at -50 ° C to -10 ° C. By storing at this temperature, stability of about 10 months, which is a sufficient storage period that does not hinder beverage production from the viewpoint of stable supply of raw materials, can be secured.

  The liquid composition according to the present invention is stored in a sealed container such as a bag-in box or an aluminum bag. In this case, heating before filling is preferable to suppress the growth of microorganisms, but on the other hand, it must be careful because it leads to scattering of aroma components.

  The liquid composition according to the present invention can be used by adding to an appropriate food or drink. For example, the liquid composition according to the present invention can be added to a normal beverage in a container. Thereby, a beverage rich in natural flavor can be provided. Further, the liquid composition according to the present invention may be frozen and solidified and stored as a solid, and thawed immediately before use, and added to beverages and other foods.

  To the liquid composition according to the present invention, a known stabilizer such as ethanol, propylene glycol, trehalose, vitamin C, and coumarin derivative is appropriately added to such an extent that the properties of the fragrance component are not changed. You may make it raise.

[Another embodiment]
In addition to roasted coffee beans, the method for producing a liquid composition in the above-described embodiment may be applied to roasted food materials such as tea, wheat, barley, brown rice, and sesame.

(Experiment 1) Relationship between dissolved carbon dioxide and volume expansion rate during freezing Roasted coffee beans were subjected to a gas-liquid countercurrent contact extraction method to obtain an extract containing aroma components. Then, the relationship between the amount of dissolved carbon dioxide in the extract and the volume expansion rate during freezing was evaluated.
A plurality of samples having different dissolved carbon dioxide concentrations were prepared by mixing the extract completely degassed by the depressurization operation and the undegassed extract at a predetermined blending ratio. Each sample was frozen in an air-tight aluminum pouch bag with 100 mL in a sealed state so that air did not enter. The total volume of each sample before and after freezing was measured by putting an aluminum pouch bag into a graduated cylinder filled with water and measuring the amount of the increased water as the total volume. The total volume defined here is a value obtained by adding the amount of gas released from the solution and the amount of freezing and expansion of the sample itself.

(Results and Discussion)
From the results shown in FIG. 1, it was clarified that the volume expansion rate during freezing increases as the dissolved carbon dioxide concentration increases. The volume expansion rate during freezing is preferably 1.5 times or less from the viewpoint of space saving during transportation, and it is further considered that a significant cost reduction is 1.3 times or less. Then, it turned out that it is desirable to make the amount of dissolved carbon dioxide into 1000 ppm or less, more preferably 500 ppm or less.

(Experiment 2) Relationship between deaeration treatment and remaining aromatic components Deaeration treatment can be considered as a method for reducing the amount of dissolved carbon dioxide in the extract. Since deaeration treatment may reduce not only dissolved carbon dioxide but also aroma components contained in the liquid, all deaeration means are compared, and the amount of dissolved carbon dioxide reduced and the remaining aroma components remain. Clarify the relationship.
[Sample adjustment]
The coffee roasted beans and pure water were pulverized to a particle size of about 1 mm while mixing at 1: 9. This liquid was operated under the following conditions using Flavortech SCC (Spinning Corn Column) as a gas-liquid countercurrent contact extraction device, and volatile components were recovered together with water vapor. The obtained volatile component was immediately cooled to 20 ° C. or lower to obtain an extract.

Raw material supply speed: 350 L / Hr
Steam flow rate: 17.5Kg / Hr
Evaporation amount: 17.5Kg / Hr
Column bottom temperature: 98 ° C
Column top temperature: 98 ° C
Degree of vacuum: atmospheric pressure

  The extraction liquid obtained above was subjected to a gas separation membrane treatment method, an air blowing method, a heating treatment method, a reduced pressure treatment method, a pervaporation membrane treatment method, and an ultrasonic treatment method for the purpose of degassing, respectively. Detailed conditions are described below. The extracted solution after the deaeration treatment was divided into samples for measuring dissolved carbon dioxide, for sensory evaluation, and for component determination, and stored at 4 ° C. and −20 ° C., respectively.

[Gas separation membrane treatment]
Using a separation membrane contactor (manufactured by Celgard: Lixel 2.5 × 8 inches) as a gas separation membrane, the treatment was performed under the following conditions. Gas-liquid contact efficiency is defined as the raw material supply flow rate divided by the membrane area and the pore area ratio, and the gas-liquid flow rate ratio is defined as the air supply flow rate divided by the raw material supply flow rate. .
Membrane area: 1.4m ²
Hole area ratio: 40%
Hole diameter: 0.04μm
Membrane material: Polypropylene Liquid passing volume: 0.40L
Air passing side volume: 0.15L
Raw material supply flow rate: 0.56 L / min to 1.12 L / min
Air supply flow rate: 0.10 L / min to 5.6 L / min
Process temperature: 5-20 degreeC
Vacuum degree: Normal pressure Gas-liquid contact efficiency: 0.001 m / min
Gas-liquid flow rate ratio: 0.20 to 10.0

[Air blowing treatment]
A glass filter (pore diameter JiS standard No. 3) was used as an air blowing device, and the treatment was performed under the following conditions.
Air supply flow rate: 5L / min
Raw material volume: 300 mL
Processing temperature: 10 ° C
Processing time: 10 seconds to 15 minutes

[Warming treatment]
The treatment was performed under the following conditions in a thermostat set to each temperature condition.
Raw material volume: 300 mL
Processing time: 15 minutes Processing temperature: 50-90 ° C
Stirrer stirring speed: Strength 2 (manufactured by Ishii Science Equipment Co., Ltd .: model number MS-2)

[Decompression treatment]
Using a rotary evaporator (manufactured by Büch: model R-205, V-805) as a decompression device, the treatment was performed under the following conditions.
Raw material liquid volume: 300 mL (1 L eggplant flask)
Processing time: 3 to 30 minutes Vacuum degree: 25 to 800 hpa
Processing temperature: 10 ° C
Rotation speed: 130rpm

(Pervaporation membrane treatment)
Using zeolite (made by Mitsui Engineering & Shipbuilding: A type 100 mm SUS pipe) as the pervaporation membrane, the treatment was performed under the following conditions.
Raw material volume: 350 mL (350 mL sealed container)
Treatment time: 30 minutes to 3 hours Vacuum degree: 0 hpa
Treatment temperature: 55 ° C-60 ° C
Stirrer stirring speed: Strength 2 (Ishii Rika Seisakusho Mfg .: Model MS-2)

[Ultrasonic treatment]
Using an ultrasonic cleaner (manufactured by ASONE) as an ultrasonic generator, the treatment was performed under the following conditions.
Raw material volume: 300 mL
Processing time: 15 minutes to 1 hour Ultrasonic intensity: 28 Hz
Processing temperature: 10 ° C
Stirrer stirring speed: Strength 2 (Ishii Rika Seisakusho Mfg .: Model MS-2)

[Measurement of dissolved carbon dioxide concentration]
The dissolved carbon dioxide concentration of the extract subjected to each deaeration treatment and the extract not subjected to the deaeration treatment was measured by the following analysis method. The results are shown in Tables 1 to 7 below and FIG.

The pH of each of the extracts is adjusted to 11 with a sodium hydroxide solution, and dissolved carbon dioxide is converted into Na ₂ CO ₃ and NaHCO ₃ into H ₂ CO ₃ . Next, the amount of H ₂ CO ₃ contained in the sample is measured using high performance liquid chromatography. In other words, the amount of dissolved carbon dioxide contained in the sample is indirectly quantified by measuring the amount of H ₂ CO ₃ .
The conditions for high performance liquid chromatography are shown below. The quantification was performed using a calibration curve prepared in advance using an aqueous sodium hydrogen carbonate solution (dissolved carbon dioxide concentration of 1000 ppm).
Equipment used: Organic acid analysis system (manufactured by Shimadzu Corporation)
Column used: Column name for analysis of hydrophilic compounds (Shimadzu Corporation: SPR-H)
Column temperature: 40 ° C
Analysis time: 18 minutes Mobile phase: 4 mM p-toluenesulfonic acid (Nacalai Tesque) aqueous solution Buffer: 4 mM p-toluenesulfonic acid aqueous solution (Nacalai Tesque) and 78 μM EDTA (Wako Pure Chemical Industries) Mixed solution with 16 mM Bis-Tris (manufactured by Nacalai Tesque) solution containing: Mobile phase flow rate: 0.8 mL / min Buffer flow rate: 0.8 mL / min Detector: Conductivity meter (manufactured by Shimadzu Corporation)

〔sensory evaluation〕
Each of the above extracts was diluted 50 times with pure water, and two specialist panelists made a comprehensive evaluation of fragrance and taste. The evaluation was expressed in three stages: good: ◯, acceptable: Δ, dissatisfied x based on the undegassed extract. The results are shown in Tables 1-7 below.

[Quantification of aroma components]
About each said extract, the amount of 2-methyl furans was measured by the head space method. The results are shown in Tables 1 to 7 below and FIG. In addition, the internal standard method was used for determination of 2-methylfuran. 250 μL of 10 g / L cyclohexanol aqueous solution of an internal standard substance and the peak area of each of 2-methylfuran were measured, and the 2-methylfuran / cyclohexanol peak area ratio of 2-methylfuran to cyclohexanol was measured. The value (A) was defined as the amount of 2-methylfuran.

Details of the headspace method are as follows.
Into a 20 mL headspace vial, take 2.5 mL of the sample and 7.25 mL of 0.17 M disodium hydrogenphosphate (Nacalai Tesque) -4.0 M sodium chloride (Nacalai Tesque) aqueous solution, and use the internal standard. As a substance, 250 μL of a 10 g / L cyclohexanol (manufactured by Nacalai Tesque) solution was added and sealed, and held at 40 ° C. for 10 minutes, and a sample was introduced into the gas chromatography using a headspace sampler. Detailed conditions are as follows.

Sampling device: Headspace sampler (manufactured by Agilent: 2.5 mL syringe)
Analytical apparatus: gas chromatography (manufactured by Agilent: GC: 6890/5973 GC-MSD)
Column: ULTRA2 (manufactured by Agilent: 50 m (length) × 0.32 mm (inner diameter) × 0.52 μm (film thickness))
Temperature conditions: 40 ° C (5 minutes hold), 40 ° C-60 ° C (4 ° C / min), 60 ° C-200 ° C (10 ° C / min)
Sample introduction conditions: inlet temperature 200 ° C., split 25: 1
Sample introduction amount: 500 μL
Gas flow rate: Helium 2.0mL / min
Mass range: 30-600 (total ions)
Scan speed: 2.58 / sec
Ionization voltage: 69.9
MS ion source 230 ° C Quadrupole 150 ° C

(Results and discussion)
Relationship between aroma component amount and sensory evaluation From Tables 1 to 7 and the results shown in FIG. . Preferably it was 5.67 (sample No. 9) or more, and it was found that the untreated product (sample No. 1) maintains a flavor that does not sink. In light of the result of Experiment 1 in this result, if the sample has a 2-methylfuran amount of 3.58 or more and a dissolved carbon dioxide amount of 1000 ppm or less, expansion during freezing due to dissolved carbon dioxide is being suppressed. Was also found to be an acceptable coffee extract. This result can be achieved by any membrane degassing means among the gas separation membrane treatment method, the air blowing treatment method, the heating treatment method, the decompression treatment method, and the pervaporation treatment method. It turns out that the desired result is not obtained. On the other hand, in the gas separation membrane treatment method, it can be seen that when the dissolved carbon dioxide is reduced, it is more difficult to reduce the aroma component as compared with other means.

(Experiment 3) Next, the influence of the liquid temperature in the gas separation membrane treatment method was examined.
The treatment conditions of the gas separation membrane were matched with those in Table 2, and the amount of dissolved carbon dioxide, the amount of 2-methylfuran when the liquid temperature was 5 ° C. and 20 ° C., and sensory evaluation were performed. The results are shown in Tables 8 and 9.

(Results and Discussion)
From the results of Tables 2, 8, 9 and FIG. 3, in the gas separation membrane treatment, the dissolved carbon dioxide amount, the amount of 2-methylfuran, and the results of sensory evaluation are not greatly different in behavior, so while leaving a scent, To remove dissolved carbon dioxide, the temperature was found to be irrelevant.

  INDUSTRIAL APPLICABILITY The present invention is useful as a technique for storing and transporting an aromatic liquid extract derived from roasted coffee beans, and can be used in the field of manufacturing coffee beverage products.

Claims (8)

A liquid composition containing an aromatic component derived from roasted coffee beans,
Aroma components containing 2-methylfuran are extracted from roasted coffee beans, and the extract is degassed by any one of a gas separation membrane treatment method, a reduced pressure treatment method, or a pervaporation membrane treatment method, thereby dissolving dissolved carbon dioxide. When the peak areas of 2-methylfuran and cyclohexanol were measured using 250 μL of 10 g / L cyclohexanol aqueous solution as an internal standard substance in the headspace method when the amount was not more than 600 ppm, A liquid composition having a methylfuran peak area ratio of 2-methylfuran / cyclohexanol of 4.48 or more.   The liquid composition according to claim 1, wherein the amount of dissolved carbon dioxide is 500 ppm or less.   The liquid composition according to claim 1, wherein the peak area ratio is 5.67 or more.   The liquid composition according to claim 1, wherein the peak area ratio is 16.2 or less.   The solid substance which freeze-solidified the liquid composition in any one of Claims 1-4.   The food / beverage products containing at least any one of the liquid composition of Claims 1-4, and the solid substance of Claim 5. A method for producing a liquid composition containing an aromatic component derived from a roasted food material, the extraction step extracting the aromatic component, and the extract obtained in the extraction step using a gas separation membrane treatment method, a reduced pressure treatment method, or A degassing step of degassing by any of the pervaporation membrane treatment methods ,
The roasted food material is roasted coffee beans, and the extraction step of extracting aromatic components containing 2-methylfuran from roasted coffee beans;
With respect to the extract obtained in the extraction step, the amount of dissolved carbon dioxide is 600 ppm or less, and 250 μL of 10 g / L of cyclohexanol is used as an internal standard substance in the headspace method. when measuring the peak areas, and the degassing step to a value of 2-methylfuran / cyclohexanol with a peak area ratio of 2-methylfuran for cyclohexanol 4.48 or more including the liquid composition Production method. The method for producing a liquid composition according to claim 7, wherein the extraction step is performed by a gas-liquid countercurrent contact extraction method.

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