JP5455331B2 - Aroma concentration method using reverse osmosis membrane - Google Patents

Description

  The present invention relates to a method for producing a natural fragrance concentrate in which a good fragrance balance of a natural raw material is maintained.

  Reverse osmosis membranes (hereinafter also referred to as RO membranes) are a type of polymer separation membrane as well as ultrafiltration membranes and microfiltration membranes, and are commonly used for filtration of pharmaceuticals, foods, and industrial products. Microfiltration membranes can remove microparticles and microorganisms of about 0.01 to several μm, and are used for sterilization and removal of turbid components. Ultrafiltration membranes are solutes with molecular weights of several hundred to several millions, which are even smaller particles. Or, since the particles can be separated, it is used for removing soy sauce and fruit juice components and deproteinization, whereas RO membranes apply seawater pressure or higher pressure to the high-concentration solution side to separate the solvent and solute from seawater. In addition to desalination, it is also used to concentrate natural products such as milk and fruit juice.

  Furthermore, there are some proposals that use RO membranes for concentration of aroma recovery products (hereinafter referred to as recovery aromas) obtained by distilling natural raw materials. Recovered incense contains high aroma components compared to extracts obtained by adding water to natural ingredients and is added to the extract or food to enhance the aroma and improve the quality. Is widely used to obtain

  As a concrete proposal, a fruit fragrance component that heats fruit juice obtained from natural fruits and concentrates the aroma component that evaporates and the recovered aroma obtained by concentrating moisture in a rectification tower 2 to 100 times with a reverse osmosis membrane. A method for producing a concentrated liquid (Patent Document 1), a distilled liquid obtained by recovering a fragrance component obtained by steam distillation of a marine product raw material as a concentrated extract with a reverse osmosis membrane, and mixing this with a concentrated liquid containing a taste component The improved method for producing a concentrated extract of marine products (Patent Document 2), the coffee extract is concentrated in a membrane, freeze-concentrated or concentrated under reduced pressure, and separated into a concentrated solution and a concentrated removal solution. The concentrated removal solution is separated by a reverse osmosis membrane. A method of obtaining a concentrated coffee liquid by mixing a concentrated aromatic liquid obtained by concentration with the concentrated liquid (Patent Document 3), membrane concentration or freeze concentration of the coffee extract, and dividing into a concentrated liquid and a concentrated removal liquid, Obtained by concentrating the concentrated removal liquid under reduced pressure A concentrated aroma liquid mixed with the concentrated liquid to obtain a concentrated coffee liquid (Patent Document 4), a fragrance component obtained by steam distillation of a marine product raw material is concentrated by a reverse osmosis membrane to obtain an aroma extract and the water vapor A method for producing an extract of a marine product with excellent flavor obtained by mixing an extract of a distillation residue or a marine product extract prepared separately (Patent Document 5) has been proposed.

  However, there is still much room for improvement in the fragrance recovery rate of the recovered scent concentrate obtained by the above proposal, and the fragrance balance of the recovered scent concentrate is significantly disrupted compared to before concentration, and a good natural feeling is obtained. There was a drawback of being damaged.

JP-A-8-215 Japanese Patent Laid-Open No. 9-9908 JP 2003-204757 A JP 2003-319749 A JP 2004-89141 A

  The present invention relates to a method for producing an excellent natural fragrance concentrate having a small fragrance reduction and good fragrance balance.

  The present inventors have made various studies in order to overcome the above-mentioned drawbacks of the concentration method using the RO membrane of recovered incense obtained by distilling natural raw materials. First, in the experiment conducted by the present inventor, when the collected incense is concentrated on the RO membrane, the fact that a part of the aroma component is adsorbed on the membrane, and the fact that a substantial part of the aroma component passes through the membrane, the passage The fact that there is a difference in the composition of the aroma components of the liquid and the original recovered incense was confirmed.

  The present inventors speculated the cause as follows. In other words, the recovered fragrance, which is separated and recovered by steam distillation or the like, is dissolved in water-soluble components or hot water that cause clogging (fouling) as in the case of concentrating natural extracts, Alternatively, since the components that gradually precipitate as a precipitate at a temperature lower than that are removed, the concentration of the RO membrane is high, while the passing speed of water is high and the concentration time is short, but the aroma components are diluted in the water. It is presumed that it will be easily adsorbed on the membrane because it exists in the state, and the membrane will also pass easily. If the RO membrane concentration is intentionally added to the recovered incense, the adsorption or passage of the aroma component will be prevented. I thought it could be suppressed.

  Therefore, after the natural raw material is distilled to obtain an aroma-recovered incense containing a fragrance, it is extracted by adding water to the distillation residue, or extracted by adding water to a natural raw material prepared separately. After mixing a part or all of the extract with a distillate containing fragrance and concentrating it using an RO membrane, as expected, the reduction of fragrance is suppressed, and an excellent natural fragrance concentrate with a good fragrance balance is obtained. As a result, the present invention has been completed.

  Thus, the present invention provides a step of obtaining a distillate containing a fragrance by distilling a natural raw material, a step of obtaining an extract by adding water to the natural raw material, and extracting the extract into the distillate containing the fragrance. The present invention provides a method for producing a natural fragrance concentrate, which comprises mixing a part or the whole of the fragrance with a reverse osmosis membrane.

  The present invention provides a distillate containing a fragrance by steam distillation of a natural raw material, and a water vapor distillation residue when obtaining the distillate is used as a natural raw material, and water is added to this to obtain an extract. The above-mentioned method is provided.

  The present invention provides the method according to any one of the above, wherein the natural raw material is coffee or tea.

  ADVANTAGE OF THE INVENTION According to this invention, the reduction | decrease of a fragrance | flavor is suppressed in concentration of collection | recovery fragrance | flavors, such as coffee, tea, and a marine product raw material, and the outstanding natural fragrance | flavor concentrate with a favorable fragrance balance can be provided. The natural fragrance concentrate obtained by the method of the present invention has a better fragrance balance and a fragrance-enhanced food and drink, for example, by blending in a food and drink with a natural fragrance concentrate obtained by a conventional method. Goods can be provided.

Hereinafter, the present invention will be described in more detail.
Examples of natural raw materials that can be used as raw materials in the method of the present invention include coffee, tea (green tea, black tea, Chinese tea, barley tea, brown rice tea, hub tea, etc.) and herbs (lavender, perilla, jasmine, sage, oregano) , Bergamot, hops, lemon balm, chamomile, rosemary, thyme, mint, coriander), fruits (apples, grapes, pineapples), nuts (walnuts, chestnuts, peanuts, etc.) However, it is not limited to these.

  These natural raw materials may be used as they are, but they may be used after enhancing or improving the aroma by heat treatment such as roasting or roasting. Moreover, you may grind | pulverize as needed and may improve the aroma collection | recovery rate by distillation.

  For example, raw green beans used for roasting coffee beans may be any of Arabica, Riberica, Robusta, etc., and any coffee beans of any origin, such as Brazil, Colombia, Indonesia, etc. Can be used. In addition, as raw raw beans, only one kind of beans may be used alone, or two or more kinds of blended beans may be used.

  A raw material obtained by roasting these green beans with a coffee roaster can be used. As a roasting method, a coffee roaster or the like can be used in a conventional manner. For example, it can be roasted by putting green coffee beans inside a rotating drum and heating the rotating drum from below with a gas burner or the like while rotating and stirring. The degree of roasting of such coffee beans may be in any range as long as it is roasted to the extent that it is usually used for drinking, but roasting to 16-30 as the L value can be exemplified. The L value is an index representing the degree of roasted coffee, and is a value obtained by measuring the lightness of the crushed coffee beans with a color difference meter. Black is represented by an L value of 0 and white is represented by an L value of 100. Accordingly, the deeper the roasted coffee beans, the lower the value and the shallower the value, the higher the value. For reference, the L value of roasted beans that are normally used for drinking is approximately the following level. Italian roast: 16-19, French roast: 19-21, Full city roast: 21-23, City roast: 23-25, High roast: 25-27, Medium roast: 27-29.

  The roasted coffee beans are subsequently pulverized, but the pulverization method is not particularly limited, any pulverization method and pulverization particle size can be adopted, and the pulverization apparatus is not particularly limited. However, it is more preferable to employ an apparatus that can be appropriately cooled in an inert gas and can be pulverized in a short time without coming into contact with the outside air, since it can prevent the fragrance from being scattered.

  For roasting or roasting products such as teas, herbs, nuts, marine products, etc., commercially available products are used, or roasting or roasting suitable for taste is performed using equipment normally used for roasting or roasting. It can also be obtained by baking.

  The steam distillation method is a method in which steam is passed through a natural raw material, and the aromatic component distilled out accompanying the steam is condensed together with the steam, pressurized steam distillation, atmospheric steam distillation, vacuum steam distillation, gas-liquid multistage type A method such as AC catalytic distillation (spinning cone column) can be employed.

  For example, in the method using atmospheric steam distillation, steam is blown from the bottom of a steam distillation kettle charged with roasted coffee beans, and the condensate is cooled by cooling the distillate with a cooler connected to the upper distillate side. A distillate containing a fragrance can be collected. If necessary, by connecting a cold trap using a refrigerant to the end of the scent collecting device, a scent component having a lower boiling point can be reliably collected. In addition, when steam distillation is carried out in the presence of an inert gas such as nitrogen gas and / or an antioxidant such as vitamin C, it is preferable because deterioration due to heating of aroma components can be effectively prevented. is there. In steam distillation, a large amount of aroma is distilled off at the beginning of distillation, and thereafter, the distillation of aroma is gradually reduced. Where to end the distillation is determined in consideration of economics and the like with reference to the results of several times. As a result, the ratio of the recovered scent to roasted coffee beans is 1: 0.5 to 1: The recovered scent of about Bx 0.5 to 5 ° is obtained.

  For example, a method in which roasted and ground coffee beans are mixed with water to form a slurry, and the flavor is recovered by a gas-liquid countercurrent contact method is, for example, a method of extraction using an apparatus described in Japanese Patent Publication No. 7-22646 Can be adopted. The means for recovering fragrance using this apparatus will be described in detail. On the rotating cone of the gas-liquid countercurrent contact extraction apparatus having a structure in which rotating cones and fixed cones are alternately combined, a liquid or paste-like structure is used. An example is a method in which a raw material for a palatable beverage is caused to flow down from the upper part and a vapor is raised from the lower part to recover an aroma component originally present in the raw material. The operating conditions of this gas-liquid countercurrent contact extraction apparatus can be arbitrarily selected depending on the processing capacity of the apparatus, the type and concentration of the raw material, the intensity of the aroma, and the like. The ratio of coffee beans to water in the coffee slurry can be any ratio as long as the coffee slurry is in a fluid state, but is approximately 5 to 30 times the amount of water with respect to 1 part by weight of the coffee beans. The amount can be exemplified. When water falls below this range, fluidity is difficult to occur, and when water is outside this range, the aroma of the resulting distillate tends to be weak.

An example of the operating conditions of the gas-liquid countercurrent contact extraction device is as follows.
Raw material supply speed: 300 to 700 L / hr
Steam flow rate: 5 to 50 kg / hr
Evaporation amount: 3 to 35 kg / hr
Column bottom temperature: 40-100 ° C
Column top temperature: 40-100 ° C
Degree of vacuum: atmospheric pressure to -100 kPa (based on atmospheric pressure)
Next, in the step of adding water to the natural raw material and extracting it to obtain an extract, the residue after the steam distillation as described above is used as the natural raw material, and the steam distillation as described above is completely separate. There are two cases of using natural raw materials. However, the procedure is basically the same, and the case will be described where the residue after the steam distillation as described above is used.

  For example, 1 to 5 times the amount of water is added to the steam distillation residue, extraction is performed at a temperature in the range of 5 ° C to 95 ° C for 0.5 to 24 hours, and after filtration, the solution is cooled to 30 ° C or less. An extract of about Bx 2 to 10 ° is obtained.

  Filtration uses filter paper, saran, and nell to remove insoluble components. In this case, a filter aid may be used in combination, for example, diatomaceous earth, acidic clay, activated clay, talc, clay, zeolite. Examples thereof include, but are not limited to, powdered cellulose. Further, it is effective to remove impurities by centrifugation as a means different from filtration, and it may be used alone or in combination with filtration.

  Moreover, you may use an enzyme at the time of this water extraction and / or after water extraction. For example, enzymes such as amylase, cellulase, mannanase, protease and lipase can be allowed to act. In some cases, addition of a water-soluble organic solvent is also effective. For example, alcohols such as methanol, ethanol, n-propanol, isopropanol, butanol, 2-butanol, t-butanol; ketones such as acetone; ethylene glycol, propylene glycol, glycerin, 1,3-butylene glycol, 1, Examples thereof include one kind of polyhydric alcohols such as 2-butylene glycol and dipropylene glycol or a mixture of plural kinds thereof. However, since the RO membrane is weak against high-concentration water-soluble solvents, it is necessary to remove almost all of the solvent or not to affect the membrane when the RO membrane is concentrated.

  A part or all of the extract is mixed with the total amount of the distillate containing aroma, and RO membrane concentration is performed. The mixing ratio is the ratio of the amount (a) of the natural raw material used to obtain the distillate and the amount (b) of the natural raw material used to obtain the extract. : The range of 3-10: 1, Preferably it is the range of 1: 1-5: 1, More preferably, the range of 1: 1-3: 1 can be mentioned. The larger the amount of solid content derived from the extract than the solid content derived from the distillate, the higher the fragrance recovery rate, and the fragrance of the fragrance concentrate becomes closer to the fragrance of the recovered fragrance before concentration. On the other hand, in the case of RO membrane concentration, the concentration of fragrance is normally about Bx30 °, which is the limit of concentration. Therefore, in order to increase the concentration of fragrance, the amount of solids other than the fragrance component derived from the extract should be smaller. preferable. Therefore, the mixing ratio of the recovered fragrance and the extract is determined in consideration of the fragrance quality and concentration of the obtained fragrance concentrate. By changing the ratio, the fragrance having an odor concentration ratio of about 1.1 to 10 is determined. A concentrate can be obtained. Since the obtained fragrance concentrate also contains non-volatile water-soluble components such as a taste component, the flavor of the food is further improved.

  The RO membrane used in the present invention is not particularly limited in its material, molecular structure and the like. For example, commercially available products are SU-720 (salt blocking rate 99.4%), SU-720F (salt blocking rate 99.4%). ), SU-720L (salt blocking rate 99.0%), SU-820 (salt blocking rate 99.75%), SU-820L (salt blocking rate 99.7%), and above, RO membrane manufactured by Toray Industries, Inc .; Low pressure spiral RO element NTR-759HR (salt rejection 99%), low pressure spiral RO element LF10 series (salt rejection 98.5%), low pressure spiral RO element ES10 (salt rejection 99.5%), low pressure Spiral RO element ES15-D (salt rejection 99.5%), low pressure spiral RO element ES20-D (salt rejection 99.7%), low pressure spiral RO element ES15-U (salt blocking rate of 93%), NTR70HG S2F (salt blocking rate of 99%), NTR759HG S2F (salt blocking rate of 99%), RO membrane manufactured by Nitto Denko Corporation; Filmtec SW30-HR320 (salt blocking) Rate 99.4%), film tech SW30-HR380 (salt blocking rate 99.4%), film tech SW30-XLE400i (salt blocking rate 99.6%), and more, RO membranes manufactured by Muromachi Technos, Inc. it can. In particular, a membrane having a salt rejection of 99% or more is preferable because a natural concentrated extract having a good aroma balance can be obtained.

  The salt rejection is a numerical value representing the permeability of the reverse osmosis membrane and indicates the difficulty of permeation of the salt dissociated into Na ions and Cl ions in water. It is displayed as a salt rejection of 99% and is generally commercially available. Some products have a salt rejection of 90-99.8%. In addition, a concentration device including an actual reverse osmosis membrane is often a device comprising a detachable cylindrical membrane module, a pump unit that circulates and supplies a liquid to be concentrated to the membrane module, a control unit, and the like. However, any format is acceptable.

  Concentration with the RO membrane is performed at an operating pressure of 0.1 to 50 MPa. The operating temperature is appropriately selected depending on the natural raw material to be concentrated, and is, for example, in a temperature range of about 5 to 50 ° C. In general, the higher the temperature, the greater the permeation rate of water, but the solubility and stability of the components contained, and the adsorptivity to the reverse osmosis membrane also differ depending on the raw materials. Do. As the RO membrane concentration progresses, water passes through the membrane and is removed. As a result, the concentration of the solid content of the concentrate increases, and the viscosity of the concentrate increases. Makes it difficult to circulate through the membrane, the pump and the pipe connecting them, and the passage of water is substantially stopped. Concentrate to this level or terminate the enrichment at any previous stage.

  The natural fragrance concentrate of the present invention obtained by the method described above can be used as it is in the form of an aqueous solution, but if desired, an excipient such as dextrin, modified starch, cyclodextrin, gum arabic or the like is added to the extract. Without addition, it can be made into a paste, and it can also be made into a powder by drying using an appropriate drying means such as spray drying, vacuum drying or freeze drying.

  If desired, the natural fragrance concentrate of the present invention may be added with any food material or additive such as natural extract, fragrance, antioxidant, pigment and vitamin obtained by other methods.

Thus, according to the present invention, for example, an appropriate amount of natural concentrate is added to beverages such as soft drinks, carbonated drinks, milk drinks and functional drinks; confectionery such as candies, cookies, cakes and jellies. Thus, it is possible to provide a food / beverage product with a good natural flavor with a good balance that the natural raw material has. In addition, according to the present invention, for example, shampoos, hair creams, other hair cosmetic bases; osiroy, lipstick, other cosmetic bases and cosmetic detergent bases; laundry detergents, disinfectants Detergents, deodorant detergents, and other various health and hygiene detergents; various health and hygiene materials such as toothpaste, tissue, and toilet paper; natural by adding an appropriate amount of natural concentrate to pharmaceuticals It is possible to provide consumer goods with improved taste and high palatability.
Hereinafter, the present invention will be described more specifically with reference to Examples and Comparative Examples.

Example 1
10 kg of commercially available roasted coffee beans, Brazil Santos # 2 (L value 16.5), are packed into each of three stainless steel columns with an inner diameter of 27 cm and a height of 57 cm, at 100 to 105 ° C. for 2.5 hours, Steam distillation was performed to obtain 54 kg of a distillate (Reference product 1, pH 3.28). Next, 30 kg of soft water of 90 ° C. was added to each column, held at 90-95 ° C. for 30 minutes, and then left for 1 hour to extract the distillation residue and filtered to obtain 81 kg of extract (B × 8.48 °). Got. An extract of 13.5 kg was added to 9 kg of the above distillate, and the pH was adjusted to 5.01 with sodium bicarbonate. Using RO membrane concentrator NTR-759HG S2F (manufactured by Nitto Denko), operating pressure of 4 MPa for about 3 hours. After the treatment, centrifugation (20 ° C., 800 × G, 5 minutes) is performed, Bx is adjusted to 20 °, 200-mesh filtration is performed, and 5.7 kg of concentrated liquid (present product 1, B × 20 °, anti-distillate) Concentration magnification: 1.58) was obtained.

Example 2
6.75 kg of the extract was added to 9 kg of the distillate obtained in Example 1, and the pH was adjusted to 5.01 with sodium bicarbonate. Then, RO membrane concentration was performed, and soft water was added to adjust to Bx20 ° to obtain a concentrate. 2.86 kg (Product 2 of the present invention, Bx20 °, distillate concentration rate: 3.15) was obtained.

Example 3
After adding 4.5 kg of the extract to 9 kg of the distillate obtained in Example 1 and adjusting the pH to 5.01 with sodium bicarbonate, RO membrane concentration was performed, and soft water was added to adjust the Bx to 20 ° to obtain a concentrate. 1.9 kg (Product 3 of the present invention, Bx20 °, concentration of distillate solution: 4.74) was obtained.

Example 4
After adding 3.38 kg of extract to 9 kg of the distillate obtained in Example 1 and adjusting the pH to 5.01 with sodium bicarbonate, RO membrane concentration was performed, and soft water was added to adjust to Bx20 ° to obtain a concentrate. 1.43 kg (Product 4 of the present invention, Bx20 °, concentration ratio of distillate was 6.29) was obtained.

Example 5
Prepare 10 kg of roasted Brazil Santos # 2 (L value 16.5), which is the same as in Example 1, and newly fill the same column as in Example 1, add 30 kg of soft water at 90 ° C, and at 90-95 ° C. After maintaining for 30 minutes, the mixture was allowed to stand for 1 hour, extracted, and filtered to obtain 27.5 kg of extract (Bx8.52 °). 9 kg of the distillate of Example 1 was added to 13.5 kg of the above extract and the pH was adjusted to 5.01 with sodium bicarbonate using an RO membrane concentrator NTR-759HG S2F (manufactured by Nitto Denko Corporation) at an operating pressure of 4 MPa. After the treatment for about 3 hours, a centrifuge treatment (20 ° C., 800 × G, 5 minutes) is performed, the pressure is adjusted to B × 20 °, 200 mesh filtration is performed, and 5.96 kg of the concentrated liquid (present product 5, B × 20 °, Concentration ratio of distillate was 1.51).

Comparative Example 1
Sodium bicarbonate was added to 9 kg (pH 3.28) of the distillate of Example 1 to adjust the pH to 5.01, and the RO membrane concentrator NTR-759HG S2F (manufactured by Nitto Denko Corporation) was used for about 3 hours of treatment at an operating pressure of 4 MPa. And 3 kg of concentrated distillate was obtained. Next, 13.5 kg (Bx8.48 °) of the extract of Example 1 was treated with NTR-759HG S2F (manufactured by Nitto Denko Corporation) at an operating pressure of 4 MPa for about 3 hours, and 4.3 kg of concentrated extract ( Bx26.6 °) was obtained.
Concentrated distillate and concentrated extract are mixed, soft water is added, adjusted to Bx20 °, sterilized at 90 ° C, cooled to below 30 ° C, filtered through 200 mesh, and concentrated solution 5.7kg (comparative product) 1, Bx20 °, distillate concentration rate: 2.09).
(sensory evaluation)
The inventive products 1 to 5 and the comparative product 1 were diluted according to the concentration ratio of the distillate and the sensory evaluation was performed by 10 panelists who were trained on the diluted product and the reference product 1. Each panelist evaluated the flavor of the reference product 1 as 10 with respect to two items of fragrance intensity and coffee feeling, showed the average value, and averaged the values of fragrance intensity and coffee feeling to make a comprehensive evaluation. The results are shown in Table 1.
(Aroma analysis)
Reference product 1, invention products 1 to 5 and comparative product 1 were analyzed by gas chromatography. The analysis results were divided into acids, esters, aldehydes, alcohols, furans, phenols, ketones, nitrogen compounds, sulfur compounds and other compounds, and changes in the amount of aroma components were compared. It was acid, furan, nitrogen compound, sulfur compound that the decrease was large in comparison product 1 compared to reference product 1, and the abundance after concentration of these components was expressed as a numerical value when 100 before concentration. . Moreover, the amount of fragrance components (ppm) of gas chromatography was added to obtain the amount of fragrance (ppm). In addition, this invention products 1-5 and the comparative product 1 were converted according to the distillate concentration ratio, and compared with the reference product 1. The results are shown in Table 1.

  As shown in Table 1, the inventive products 1 to 5 all had higher fragrance strength and fragrance balance and higher overall evaluation than Comparative Product 1. In particular, the inventive products 1, 2 and 5 were very good because the aroma balance of the reference product 1 before concentration was maintained. Further, the amount of fragrance (ppm) was higher than that of the comparative product 1 in any of the inventive products 1 to 5. In Comparative Product 1, the abundance of acid, furan, nitrogen compound, and sulfur compound was 77, 65, 74, 30 with reference product 1 being 100, but in any case of Invention Products 1-5 The value was higher than that of Comparative Product 1. These components are important aroma components of coffee, and the high value of these components is a result supporting improvement of the aroma balance. In particular, the sulfur compound is a component that greatly affects the coffee aroma even in a small amount, but the numerical values of the products 1 to 5 of the present invention are very high as 85 to 105, which is much higher than that of the comparative product 1 in terms of aroma recovery. Improvement effect was seen.

Example 6
5 kg of commercially available sencha was packed in each of three stainless steel columns having an inner diameter of 27 cm and a height of 57 cm, and subjected to steam distillation at 100 to 105 ° C. for 2 to 3 hours, and 30 kg of distillate (reference product 2, pH 4. 56) was obtained. Next, 15 kg of 50 ° C. soft water was added to each column, extraction was performed at 50 to 55 ° C. for 30 minutes, and filtration was performed to obtain 36 kg (B × 7.48 °) of an extract. 9 kg of the extract was added to 7.5 kg of the above distillate, and the pH was adjusted to 5.01 with sodium bicarbonate using an RO membrane concentrator NTR-759HG S2F (manufactured by Nitto Denko) for about 3 hours at an operating pressure of 4 MPa. After the treatment, centrifuge treatment (20 ° C, 800 × G, 5 minutes) is performed, Bx is adjusted to 20 °, 200 mesh filtration is performed, and 3.35 kg of concentrated solution (Product 6 of the present invention, Bx20 °, anti-distillate) Concentration magnification: 2.24) was obtained.

Example 7
By adding 6.75 kg of the extract to 4.5 kg of the distillate obtained in Example 6 and adjusting the pH to 5.01 with sodium bicarbonate, RO membrane concentration is performed, and soft water is added to adjust to Bx20 °. 2.51 kg of concentrated liquid (Invention product 7, Bx20 °, concentration ratio of distillate liquid: 1.79) was obtained.

Example 8
By adding 4.5 kg of the extract to 4.5 kg of the distillate obtained in Example 6 and adjusting to pH 5.01 with sodium bicarbonate, RO membrane concentration is performed, and soft water is added to adjust to Bx20 °. 1.67 kg of concentrated liquid (Product 8 of the present invention, Bx20 °, concentration ratio of distillate liquid: 2.69) was obtained.

Example 9
By adding 3.38 kg of the extract to 4.5 kg of the distillate obtained in Example 6 and adjusting to pH 5.01 with sodium bicarbonate, RO membrane concentration is performed, and soft water is added to adjust to Bx20 °. Concentrated liquid 1.25 kg (Product 8 of the present invention, B × 20 °, concentration ratio of distillate liquid: 3.6) was obtained.

Comparative Example 2
Sodium bicarbonate was added to 7.5 kg of the distillate obtained in Example 6 to adjust the pH to 5.01, and the RO membrane concentrator NTR-759HG S2F (manufactured by Nitto Denko Corporation) was used for about 3 hours of treatment at an operating pressure of 4 MPa. 1 kg of concentrated distillate was obtained. Next, 9 kg (Bx7.48 °) of the extract of Example 6 was treated with NTR-759HG S2F (manufactured by Nitto Denko Corporation) at an operating pressure of 4 MPa for about 3 hours, and 2.5 kg (Bx26. 8 °).

Concentrated distillate and concentrated extract are mixed, soft water is added, adjusted to Bx20 °, sterilized at 90 ° C, cooled to 30 ° C or lower, filtered through 200 mesh, and 3.4 kg of concentrated solution (comparative product) 2, Bx20 °, distillate concentration rate: 3.0).
(sensory evaluation)
The inventive products 6 to 9 and the comparative product 2 were diluted according to the concentration ratio of the distillate, and sensory evaluation of these diluted products and the reference product 2 was performed by 10 trained panelists. The results are shown in Table 2.

  As shown in Table 2, the fragrance flavors of the inventive products 6 to 9 had higher fragrance strength and fragrance balance, higher overall evaluation, and good sencha feeling compared to Comparative Product 2. In particular, the products 5 and 6 of the present invention were very good because the same fragrance balance as that of the reference product 2 before concentration was maintained.

Example 10
5 kg of commercially available bonito polishing powder (which is also called G powder, which is generated by grinding around with a grinder when shaping the bonito) is packed into each of a stainless steel column having an inner diameter of 27 cm and a height of 57 cm. Then, steam distillation was performed for 2 to 3 hours to obtain 30 kg of a distillate (Reference product 3, pH 4.65). Next, 50 kg of 95 ° C. soft water was added to each column, extraction was performed at 90 to 95 ° C. for 30 minutes, and filtration was performed to obtain 123 kg (B × 2.0 °) of an extract. Sodium bicarbonate was added to 5 kg of the above distillate to adjust the pH to 5.01, 20.5 kg of the extract was added and mixed, and RO membrane concentrator NTR-759HG S2F (manufactured by Nitto Denko Corporation) was used, and the operating pressure was 4 MPa. After about 3 hours of treatment, centrifuge treatment (20 ° C., 800 × G, 5 minutes) is performed, Bx is adjusted to 20 °, 200 mesh filtration is performed, and 2.0 kg of concentrated solution (Product 10 of the present invention, B × 20 °). )

Example 11
After adding 10.25 kg of the extract to 5 kg of the distillate obtained in Example 10 and adjusting the pH to 5.01 with sodium bicarbonate, RO membrane concentration was performed, and soft water was added to adjust to Bx20 ° to obtain a concentrate. 1.01 kg (Invention product 11, Bx20 °) was obtained.

Example 12
After adding 6.83 kg of the extract to 5 kg of the distillate obtained in Example 10 and adjusting the pH to 5.01 with sodium bicarbonate, RO membrane concentration was performed, and soft water was added to adjust to Bx20 ° to obtain a concentrate. 0.68 kg (Invention product 12, Bx20 °) was obtained.

Example 13
After adding 5.13 kg of the extract to 10 kg of the distillate obtained in Example 10 and adjusting the pH to 5.01 with sodium bicarbonate, RO membrane concentration is performed, and soft water is added to adjust the Bx to 20 ° to obtain a concentrate. 0.52 kg (Invention product 12, Bx20 °) was obtained.

Comparative Example 3
Sodium bicarbonate was added to 5 kg of the distillate obtained in Example 10 to adjust the pH to 5.01, and the RO membrane concentrator NTR-759HG S2F (manufactured by Nitto Denko) was used, and the treatment was performed at an operating pressure of 4 MPa for about 3 hours. 1.3 kg of concentrated distillate was obtained. Next, the extract of Example 10 (10.25 kg (Bx7.48 °)) was treated with NTR-759HG S2F (manufactured by Nitto Denko Corporation) at an operating pressure of 4 MPa for about 3 hours, and 3.14 kg of concentrated extract ( Bx24.3 °) was obtained.

Concentrated distillate and concentrated extract are mixed, soft water is added, adjusted to Bx20 °, sterilized at 90 ° C, cooled to 30 ° C or lower, filtered through 200 mesh, and concentrated solution 3.8kg (comparative product) 2, Bx20 °).
(sensory evaluation)
The inventive products 10 to 13 and the comparative product 3 were diluted according to the concentration ratio of the distillate, and sensory evaluation was performed by 10 panelists who were trained on the diluted product and the reference product 3. The results are shown in Table 3.

  As shown in Table 3, the fragrance flavors of the inventive products 10 to 13 were higher in fragrance strength and fragrance balance, higher in overall evaluation than the comparative product 3, and had an elegant flavor possessed by bonito. In particular, the products 10 and 11 of the present invention were very good because the same fragrance balance as that of the reference product 3 before concentration was maintained.

Claims (2)

The following process:
(A) A step of steam-distilling roasted coffee beans to obtain a distillate containing aroma,
(B) A step of adding water to the steam distillation residue generated in step (A) and extracting it to obtain an extract,
(C) A coffee characterized by mixing part or all of the extract of (B) with the distillate of (A) , adjusting the mixture to pH 5.01, and concentrating using a reverse osmosis membrane. A method for producing an aroma concentrate. The method for producing a coffee aroma concentrate according to claim 1, wherein the abundance of the sulfur compound in the coffee aroma concentrate is 85 to 107% before the concentration .