JP5814658B2 - Coffee oil production method - Google Patents

Description

  The present invention relates to coffee oil and a method for producing the same. More specifically, the present invention relates to a method for obtaining a crude coffee oil from roasted coffee beans and separating and purifying the coffee oil (essential oil) efficiently and simply from the crude coffee oil.

  Plant essential oils are often used to give foods such as beverages, jellies, chewing gums, and candy, fresheners in the mouth, toothpastes, fragrances, cosmetics such as cosmetics, pharmaceuticals, and tobacco. Yes. Plant essential oils are generally collected by steam distillation, organic solvent extraction, supercritical extraction, pressing, and the like.

  For example, in the case of coffee oil (also referred to as coffee essential oil), it is known that it can be obtained from roasted coffee beans using an extraction method such as a steam distillation method, a pressing method, a supercritical fluid extraction method, The coffee beans are loaded into a biaxial extruder and pressed while heating to separate and extract the oil component (Patent Document 1), the step of roasting coffee, and the roasting A method for producing coffee oil (Patent Document 2) is proposed, which includes a step of compressing coffee beans while maintaining the coffee beans at 20 ° C. to 80 ° C. in a pressing device, and a step of separating coffee oil that is an oil component from the coffee beans. Has been.

Japanese Patent Laid-Open No. 62-126935 JP 2008-125483 A

  In conventional oil collection methods, the heat history may be large and the quality of aroma components may be reduced, miscellaneous components may be collected together, and turbidity may occur due to contact with a large amount of water during oil collection For some reasons, the presence of water or an organic solvent may cause a decrease in the titer of the flavor component, so that it is not always possible to obtain coffee oil that is satisfactory in quality. In particular, when separating the essential oil from roasted coffee beans, it is difficult to separate the essential oil stored in the oil cells, resulting in poor aroma quality and high cost.

  An object of the present invention is to provide a method for producing coffee oil, which can improve poor aroma quality and high cost, which are disadvantages of conventional coffee oil.

  As a result of intensive studies to solve the above-mentioned problems, the present inventors have crushed roasted coffee beans, mixed with water, and centrifuged to obtain a coffee oil-containing part of an O / W emulsion (hereinafter referred to as “crude oil”). It was found that coffee oil can be easily obtained by de-emulsifying this emulsion and separating and recovering the oil phase, and that freeze-thawing is useful for de-emulsifying crude oil. It came to be completed.

That is, although this invention is not limited to the following, the manufacturing method of (1)-(3) is provided.
(1) The following steps;
Step 1 of crushing roasted coffee beans and adding water to form an O / W emulsion containing coffee oil as oil droplets,
Step 2 of centrifuging the liquid containing the O / W emulsion to obtain a crude coffee oil
Step 3 for demulsifying the crude oil, and Step 4 for separating and recovering the oil phase
A method for producing coffee oil, comprising:
(2) The method according to (1), wherein the demulsification process in step 3 is a freeze-thaw process.
(3) The method according to (2), wherein the crude oil in Step 2 is an oil part obtained by three-phase separation of a slurry after subjecting the wet pulverized product of roasted coffee beans to stripping treatment.

According to another aspect, the present invention provides (4) coffee oil.
(4) Coffee oil obtained by the method according to any one of (1) to (3).
According to another aspect, the present invention provides the coffee product of (5).
(5) A coffee product containing the coffee oil according to (4).

  In the method of the present invention in which coffee oil is separated by de-emulsifying the O / W emulsion, the separated oil is hardly flocked or emulsified again, so that no complicated work is required and a short time is required. Can produce coffee oil efficiently.

  Further, in the method of the present invention using demulsification by freezing and thawing, no chemical addition for demulsification is required, and no heating for oil collection is required. Can be manufactured. Furthermore, it is advantageous in that no special device is required.

  The present invention provides a method for producing coffee oil. In the production method, roasted coffee beans are pulverized and added, mixed and stirred strongly, and coffee oil (essential oil) is dispersed as fine monomer phase droplets in the aqueous phase, that is, an O / W emulsion is formed. 1, a process 2 for centrifuging the liquid of process 1 to obtain a crude coffee oil, a process 3 for subjecting the crude oil to a demulsification process, and a process 4 for separating and recovering the oil phase. Hereinafter, preferred embodiments for each step will be described.

(Step 1 for forming O / W emulsion)
The coffee beans used in the present invention are not particularly limited, and may be obtained by any method as long as it is roasted coffee beans. For example, cultivated tree species of coffee beans include arabica species, canephora species, and revelica species, and varieties include mocha, Brazil, Colombia, Guatemala, Blue Mountain, Kona, Mandelin, Kilimanjaro, and the like.

  Raw coffee beans can be roasted using a general roasting machine (horizontal drum type roasting machine), and roasting methods are classified into heating methods, direct fire, hot air, far infrared rays. Microwave or the like can be used. In addition, roasting degree is an 8-stage designation of the US method, and can be used for any of light roast, cinnamon roast, medium roast, high roast, city roast, full city roast, French roast, and Italian roast. However, since coffee oil is more easily eluted when roasted deeply, it is preferable to use coffee beans roasted more than city roast as roasted coffee beans. In addition, the beans to be used can be used by mixing a plurality of beans with different origins, varieties, and roasting degrees.

  Such roasted coffee beans are pulverized, hydrated, mixed and stirred vigorously, and the essential oil is dispersed as fine monomer phase droplets in the aqueous phase to form an O / W emulsion. Although roasted coffee beans can be crushed by either dry pulverization or wet pulverization, wet pulverization is efficient to disperse the essential oil in the aqueous phase and it is easy to prevent fragrance scattering. preferable. In particular, when roasted coffee beans are pulverized by wet pulverization, in order to prevent temperature rise and fragrance scattering during pulverization, water is continuously added during pulverization, and the final ratio of roasted coffee beans and water is the target ratio. It is preferable to pulverize while controlling so as to be. Examples of the pulverizer include Fitzmill (manufactured by FITZPATRICK) and Commitolol (manufactured by Archer).

  Although there is no restriction | limiting in particular about the grinding | pulverization particle size of roasted coffee beans, It is preferable to destroy a cell to the magnitude | size which an essential oil component elutes easily. From this viewpoint, the roasted coffee beans are preferably pulverized to an average pulverized particle size of about 0.1 mm to 4 mm, more preferably about 0.1 mm to 2 mm. In addition, the average grinding | pulverization particle size (particle size) of a ground coffee bean can be measured, for example using a low tap sieve shaker (made by Tanaka Tech Co., Ltd.).

  Tap water, ion exchange water, deoxygenated water, pure water, ground water, etc. can be used to add the roasted coffee beans to the pulverized product. Stabilizers and pH adjusters are added to these waters. Can also be used. The ratio (weight) of coffee beans to water is preferably 1: 3 to 1: 100, more preferably 1: 5 to 1:50, still more preferably 1: 5 to 1:20, and particularly preferably 1: 5. It is about 1:10.

  The mixture of crushed roasted coffee beans and water thus obtained is vigorously stirred to disperse the essential oil as droplets in the aqueous phase. The stirring condition is not particularly limited as long as the O / W emulsion is formed. In addition, the stirring conditions vary depending on the size of the stirring blades and the like, so the stirring conditions cannot be defined uniformly. However, for example, when the bamix model 133 is used, 11600-16000 rpm, About 1 to 20 minutes. Moreover, when the temperature at the time of stirring is heated to 30 ° C. or more (preferably 30 to 60 ° C., more preferably 30 to 50 ° C., and further preferably 30 to 45 ° C.), roasted coffee beans containing crude oil and water Since the viscosity of this mixture is reduced, a crude oil can be obtained more efficiently. Whether or not the O / W emulsion is formed can be determined by whether or not the crude oil is easily dispersed when it is put in water.

  As the mixture obtained by vigorously stirring the crushed roasted coffee beans and water in Step 1 of the present invention, a slurry after stripping treatment, a slurry after steam treatment, or the like can also be used. Here, the stripping process refers to a process of concentrating the volatile components in the slurry to the gas phase by bringing the heat source and the slurry into countercurrent contact and performing rectification, and as an apparatus therefor, an SCC (Spinning Cone Column And Flavor Tech Co., Ltd.). For example, a mixture of roasted coffee beans obtained by wet pulverization and water (also referred to as a slurry) is subjected to stripping treatment or steam distillation to recover the aroma component-containing condensate, and the remaining slurry is the present invention. Coffee oil is obtained by using for the process after the process 2 of this. Thereby, the crude oil after the stripping process that has been only discarded can be used effectively.

(Step 2 for obtaining crude oil)
The liquid containing the O / W emulsion obtained in step 1 is centrifuged to obtain a coffee oil-containing part (crude oil). The centrifuge is not particularly limited as long as it has a function capable of separating crude oil, and a batch-type centrifuge or a three-phase separator that can be continuously processed can be used. It is preferable to use a three-phase separator. An example of such a centrifuge is CRPX918 (manufactured by Alfa Laval). Using a three-phase separator, it can be efficiently separated into a) crude oil, b) extract, c) coffee residue (also called insoluble fine particles, sludge), and the desired a) crude oil can be easily separated. be able to. When separating crude oil by centrifugation, it is preferable to apply a centrifugal force of 2000 to 10,000 G. The crude oil that has floated can be separated and recovered by performing a known operation such as decantation as necessary.

(Step 3 of demulsifying the O / W emulsion)
In Step 3, a clarified coffee oil (essential oil) is obtained by de-emulsifying the crude oil O / W emulsion recovered in Step 2 to separate the oil component. The method of demulsification is not particularly limited, but the crude oil of coffee contains a lot of solids and moisture, so that the essential oil can be separated by applying an electric field or applying physical force such as centrifugation. It has been found that it does not occur, that is, no demulsification takes place. Although there is a method of extracting essential oil by adding ethanol, it is not preferable because the essential oil is diluted with ethanol and the aroma titer is lowered. Even when ethanol is volatilized and only the essential oil component is extracted after extraction with ethanol, there is a concern that the aromatic component of the essential oil disappears with heating.

  According to the study by the present inventors, it was found that when the crude oil O / W emulsion was subjected to freeze-thaw treatment, the emulsion breakage (demulsification) occurred easily and effectively. At this time, it was found that the emulsion becomes unstable and oil-water separation occurs by applying a force that promotes separation such as centrifugal force or standing, and the essential oil can be easily separated. Therefore, it is preferable to use a freeze-thaw process as the demulsification process of the present invention.

  In the freezing and thawing treatment, the freezing conditions are not particularly limited as long as the entire crude oil is frozen. If freezing conditions are set so that the passage time of the maximum ice crystal formation zone (0 to -5 ° C) in which ice crystals grow without causing supercooling is increased, the ice crystals are formed when the aqueous phase freezes. It is thought that it grows large and becomes coarse, and oil droplets are pressed against each other to cause partial coalescence, so that emulsion breakage easily occurs. Accordingly, as a preferred freezing condition, the lower limit of the freezing rate when the center temperature of the crude coffee oil passes from 0 ° C. to −5 ° C. (maximum ice crystal formation zone) is 1 ° C./min (preferably 0.5 ° C./min). The freezing conditions are more preferably 0.1 ° C./min).

  There is no particular limitation on the thawing conditions as long as the entire frozen crude oil dissolves. Oil droplets partially coalesced by freezing cause coalescence due to melting of the oil phase, resulting in complete emulsion breakage. Thawing may be performed by any method such as air thawing (natural thawing), thawing in running water, and thawing by heating. When it is necessary to shorten the thawing time, it is effective to thaw in running water or to warm and thaw. When heating, in order to prevent quality deterioration of the coffee oil, it is heated so that the temperature of the central portion of the oil part is about 50 ° C. or less (preferably about 45 ° C. or less, more preferably about 40 ° C. or less). Is preferred. Moreover, you may accelerate | stimulate thawing | decompression using a reduced pressure kneader.

(Step 4 of separating the oil phase)
The emulsion becomes unstable by the demulsification in step 3, and the oil phase is separated on the upper side and the aqueous phase is separated on the lower side. The separation may be promoted by leaving it as it is, but it is preferable to promote the separation by applying a centrifugal force. As the centrifugal separation treatment, it is preferable to apply a centrifugal force of about 2000 to 10,000 G. After centrifugation, the interface between the oil phase and the water phase is separated very clearly, so that well-known operations such as decantation can be performed, and the upper layer (oil phase) can be easily separated and recovered. (Clarified coffee oil) can be easily obtained.

  Thus, the method of the present invention is characterized by producing an O / W emulsion, demulsifying the emulsion, and collecting coffee oil. The oil component is not contaminated with other components, and the oil component is hardly contaminated with the extract portion obtained by stripping which is one of the preferred embodiments. Can be manufactured.

(Coffee product manufacturing method)
The coffee oil obtained in the present invention imparts a preferred scent to foods such as beverages, jellies, chewing gums and candies, mouth fresheners, toothpastes, fragrances, cosmetics such as cosmetics, pharmaceuticals, and tobacco. Used as a flavor enhancer. In particular, when the coffee oil obtained by the present invention is added to a coffee product such as a container-packed coffee beverage that can be stored for a long period of time or powdered coffee that is dissolved and drunk with water or hot water (also called a soluble coffee product or instant coffee). Thus, only the preferable richness and aroma of coffee can be enhanced without accompanying miscellaneous taste and bitterness, and a coffee beverage that reproduces the taste of freshly brewed coffee is obtained.

Conventionally known methods such as a method for adding coffee oil and a method for producing a food blended with coffee oil can be employed. A method for producing a coffee oil-containing beverage will be described.
As a general method for producing a coffee drink, for example, roasted coffee beans are pulverized and extracted with hot water, and then added with sugar solution, milk, dairy products, and other additives. Thereafter, this is homogenized, heat sterilized, filled in a container, and finally sterilized at high temperature and high pressure (retort) to obtain a product. In the production of a coffee beverage using the coffee oil of the present invention, the coffee beverage can be basically produced according to a conventional method, but the coffee beverage is in an emulsified form so that the coffee oil is stably present in the coffee beverage. It is important to make it contain.

  The emulsification of coffee oil is performed by adding an emulsifier and, if necessary, pure water to the coffee oil, mixing and preliminarily emulsifying, and then homogenizing under high pressure with a homogenizer or the like. The pre-emulsified product is treated with a high-pressure homogenizer to obtain a coffee oil emulsion, which can be added to a coffee beverage preparation (mixed with coffee extract, milk / dairy products, sugar, flavors, etc.) Alternatively, the pre-emulsified product may be mixed with a coffee beverage preparation and then subjected to a high-pressure homogenizer treatment.

Examples of the emulsifier used for emulsification of coffee oil include glycerin fatty acid ester, sucrose fatty acid ester, sorbitan fatty acid ester, propylene fatty acid ester, lecithin, quilaya extract and the like. Preliminary emulsification conditions are not particularly limited, but an operation of stirring at a temperature of 40 to 70 ° C. (preferably 50 to 60 ° C.), a rotational speed of 2500 to 3500 rpm (preferably 3000 rpm), and 10 to 30 minutes (preferably 15 to 25 minutes). Can be illustrated. As the high pressure homogenization, pressure 100~250kgf / cm ² (preferably 100~200kgf / cm ²⁾ can be exemplified about operation.

  The addition amount of the coffee oil may be appropriately set depending on the quality (titer) of the coffee oil and the desired flavor of the coffee product. Usually, the concentration of the coffee oil in the final product is 10 to 100 ppm, preferably 30 to 50 ppm. Add to be.

  A coffee beverage preparation containing the coffee oil thus obtained in the form of an emulsion is heat sterilized, filled into a container, and then retort sterilized as necessary to obtain a coffee oil-containing beverage.

EXAMPLES Hereinafter, although an Example is shown and the detail of this invention is demonstrated concretely, this invention is not limited to this.
Example 1. Production of coffee oil Roasted coffee beans (Arabica, L value of about 20) are mixed with 5 to 10 times (by weight) water and wet-ground using Commitolol (Archell) to produce coffee slurry. Obtained. Pass the coffee slurry through SCC (Flavour Tech Co., Ltd.), divide the slurry coming out from the lower part into a coffee cocoon part and an extract part with a decanter, and further subject the extract part to three-phase centrifugation to obtain a crude oil part and a clarified extract. And three phases of coffee fine particles (sludge).

  After recovering the crude oil part, it was packed in a 10 L container or the like and frozen in a -20 ° C. freezer for 24 hours. After confirming complete freezing, the crude oil was taken out and dissolved by natural dissolution. After confirming complete dissolution, the mixture was centrifuged (6500 rpm, 30 minutes), and the oil phase was recovered to obtain clarified coffee oil. When the physical properties were evaluated, the viscosity (B-type viscometer (BROOKFIELD, DV-II + Pro), measurement temperature 25 ° C.) was 110 mPa / s, and the turbidity (LaMotte, 2020 eTURBIDIMETER) was 938 NTU.

  In addition, this coffee oil is stored at various temperatures (−20 ° C., 5 ° C., 23 ° C., 37 ° C.) for 4 weeks, its flavor and appearance are evaluated by sensory evaluation, and the degree of oxidation is determined according to the standard oil analysis method. Evaluation was made by measurement. The results are shown in Table 1. There was no significant change in flavor at any temperature, and the degree of oxidation hardly changed, suggesting that the coffee oil obtained in the present invention was excellent in stability.

Example 2 Production of coffee oil-containing beverage A 10-fold amount (by weight) of water (90 ° C.) was added to roasted coffee beans (Arabica species, L value of about 21), followed by drip extraction to obtain a coffee extract. Predetermined amounts (Table 2) of granulated sugar and sodium bicarbonate were added to about 0.3 L of this extract to adjust the pH to about 6 (coffee solution).

Next, 0.7 g / L of coffee oil obtained in Example 1, emulsifier (sucrose fatty acid ester: 0.5 g / L, glycerin fatty acid ester: 0.1 g / L), casein Na (1.6 g / L) ), Skim milk powder 2.0 g / L and water were mixed and dissolved, and then pre-emulsified (homogenized) with a homogenizer to obtain a coffee oil emulsion (temperature 60 ° C., pressure 150 kgf / cm ² ).

After adding the coffee liquid, coffee oil emulsion, and the remaining raw materials (raw milk, coffee extract, fragrance), homogenization was performed using a high-pressure homogenizer at a temperature of 60 ° C. and a pressure of 200 kgf / cm ² (coffee blending). Liquid Brix: adjusted to 8.6, pH: 6.3). This coffee beverage preparation was filled into a can container (190 mL) and wound, and then subjected to high-temperature and high-pressure (retort) sterilization at 124 ° C. for about 20 minutes to produce a coffee oil-containing beverage. For comparison, a coffee drink produced in the same manner except that no coffee oil was blended was obtained. Table 2 shows the blending composition per liter of coffee beverage product.

  Sensory evaluation was conducted by 7 expert panelists, and the strength of coffee was strong and the strength of body feeling (brightness) was evaluated by consultation. The results are shown in Table 3. The coffee beverage to which the coffee oil of the present invention was added had a rich coffee aroma from middle to last. In addition to the aroma, the overall coffee taste was also improved. That is, when the coffee oil of the present invention is used, coffee feeling and body feeling can be enhanced without accompanying miscellaneous taste and bitterness, and a coffee beverage that reproduces the taste of freshly brewed coffee can be obtained. Was suggested.

Claims (2)

The following steps:
Step 1 of crushing roasted coffee beans and adding water to form an O / W emulsion containing coffee oil as oil droplets,
Step 2 of centrifuging the liquid containing the O / W emulsion to obtain a crude coffee oil
Step 3 for subjecting the crude oil to a demulsification treatment, wherein the demulsification treatment is a freeze-thaw treatment, and Step 4 for separating and recovering the oil phase
A method for producing coffee oil, comprising: The method according to claim 1 , wherein the crude oil in step 2 is an oil part obtained by three-phase separation of the slurry after the stripping treatment is performed on the wet pulverized product of roasted coffee beans.