Coffee bean processing methods

Abstract

To provide a method for producing coffee beans for roasting that can be used in the production of a packed coffee drink with reduced off-flavors derived from the purification process of raw coffee beans; a method for producing roasted coffee beans using the coffee beans for roasting; coffee extract obtained from the roasted coffee beans; and a packed coffee drink including the coffee extract.SOLUTION: Coffee beans for roasting are produced by a production method that includes: a step A for fermenting coffee cherry pulp with microbes; and a step B for mixing the coffee cherry pulp fermented in the step A with raw coffee beans or coffee cherry and then fermenting the mixture, thereby producing the coffee beans for roasting.SELECTED DRAWING: None

Description

[[Technical Field]]

[0001] The present invention relates to a method for producing coffee beans for roasting, a method for producing roasted coffee beans, a coffee extract, a packaged coffee beverage, and the like. [[Background Art]]

[0002] Coffee is a broad-leaved shrub belonging to the genus Coffea of the family Rubiaceae. A coffee fruit is an oval fruit borne on a coffee tree; it is green when unripe, and turns reddish purple when ripe. Depending on the variety, a few trees rarely bear yellow fruits. Coffee fruits are also called coffee cherries. A coffee cherry contains two seeds that face each other, and the portion of these two seeds is called green coffee beans. Furthermore, from the outside to the inside, a coffee cherry has a structure consisting of exocarp, pulp, mucilage (a viscous liquid containing sugar), endocarp (parchment), silver skin, and seed (green coffee bean).

[0003] Green coffee beans are the only raw material used to obtain roasted coffee beans for coffee beverages. Accordingly, a large amount of pulp and peel are generated during the refining process of extracting green coffee beans from coffee cherries. At present, there are almost no applications for these materials, and they are discarded, which has exacerbated waste and environmental problems.

[0004] By the way, the main methods for producing coffee beverages from coffee cherries are outlined below. First, the green coffee beans are processed (separated) from the coffee cherries. The main methods for this processing are the washed method and the natural method. In the natural method, after harvesting, the coffee cherries are usually dried, and then the parts covering the green coffee beans (e.g., the outer skin, pulp, inner skin, and silvery membrane) are removed using a dehulling machine or the like to separate the green coffee beans. On the other hand, in the washed method, after harvesting, the outer skin and pulp are usually removed from the coffee cherries without drying them, and the mucilage is exposed on the surface of the coffee beans. The beans are then fermented to remove the mucilage, and then the beans are dried, and the inner skin and silvery membrane are removed using a dehulling machine or the like to separate the green coffee beans. Roasted coffee beans are obtained by roasting the green coffee beans that have been refined. The roasted coffee beans are ground, and the extract obtained by extracting the coffee flavor components with hot water is provided as a coffee beverage. However, in the above-mentioned refining process of green coffee beans (drying or fermentation), off-flavors sometimes occurred when coffee beverages were produced from these green coffee beans due to spoilage by environmental bacteria during drying or fermentation.

[0005] On the other hand, Patent Document 1 discloses a method for producing roasted coffee flavor components, characterized by crushing green coffee beans, inoculating them with Aspergillus oryzae and culturing them at pH 6.5 to 3.0, roasting the culture at 130 to 210°C, and collecting the resulting flavor components. However, it was not known that producing coffee beans for roasting using a method that includes step A, in which coffee cherry pulp is fermented with microorganisms; and step B, in which the coffee cherry pulp fermented in step A is mixed with green coffee beans or coffee cherries and fermented, can effectively suppress the aforementioned off-flavors when a coffee beverage is produced using such roasted coffee beans. [Prior art documents] [Patent Documents]

[0006] [Patent Document 1] Japanese Patent Application Publication No. 1-112950 [Overview of the project] [Problems that the invention aims to solve]

[0007] The object of the present invention is to provide a method for producing roasted coffee beans that can be used in the production of a packaged coffee beverage in which off-flavors derived from the refining process of green coffee beans are suppressed, a method for producing roasted coffee beans using such roasted coffee beans, a coffee extract obtained using such roasted coffee beans, and a packaged coffee beverage containing such coffee extract. [Means for solving the problem]

[0008] As a result of diligent research to solve the above problems, the inventors of the present invention have found that by mixing coffee cherry pulp, which has been pre-fermented with microorganisms, with green coffee beans or coffee cherries and fermenting the mixture, it is possible to obtain a coffee beverage in which off-flavors derived from the green coffee bean refining process are suppressed, and have completed the present invention.

[0009] In other words, the present invention is (1) Step A of fermenting coffee cherry pulp with microorganisms; and, Step B involves mixing the coffee cherry pulp fermented in Step A with green coffee beans or coffee cherries and fermenting it to obtain coffee beans for roasting; A method for producing coffee beans for roasting, including; (2) The method for producing the product described in (1) above, wherein the microorganism is lactic acid bacteria or koji mold; (3) A method of production as described in (1) or (2) above, wherein lactic acid bacteria are used as the microorganism and aerobic fermentation is carried out as the fermentation, or koji mold is used as the microorganism and anaerobic fermentation is carried out as the fermentation; (4) The manufacturing method according to any of (1) to (3) above, wherein sterilized coffee cherry pulp is used as the coffee cherry pulp in step A; (5) A method for producing roasted coffee beans, comprising step C of roasting coffee beans produced by any of the manufacturing methods described in (1) to (4) above to obtain roasted coffee beans; (6) Roasted coffee beans produced by the manufacturing method described in (5) above; (7) Coffee extract obtained by extracting the ground roasted coffee beans described in (6) above with water; (8) A packaged coffee beverage containing the coffee extract described in (7) above; (9) Process A: Fermenting coffee cherry pulp with microorganisms; Step B involves mixing the coffee cherry pulp fermented in step A with green coffee beans or coffee cherries and fermenting it to obtain coffee beans for roasting; and Step C involves roasting the coffee beans obtained in Step B to obtain roasted coffee beans. including, A method for suppressing off-flavors in a coffee beverage produced from the aforementioned roasted coffee beans; Regarding etc. [Effects of the Invention]

[0010] According to the present invention, it is possible to provide a method for producing roasted coffee beans that can be used in the production of a packaged coffee beverage in which off-flavors derived from the refining process of green coffee beans are suppressed, a method for producing roasted coffee beans using such roasted coffee beans, a coffee extract obtained using such roasted coffee beans, and a packaged coffee beverage containing such coffee extract. [Modes for carrying out the invention]

[0011] The present invention [1] A method for producing coffee beans for roasting, comprising: step A, fermenting coffee cherry pulp with microorganisms; and step B, mixing the coffee cherry pulp fermented in step A with green coffee beans or coffee cherries and fermenting it to obtain coffee beans for roasting (hereinafter also referred to as "the method for producing coffee beans for roasting of the present invention"). [2] A method for producing roasted coffee beans, comprising step C of roasting the coffee beans produced by the method for producing roasted coffee beans of the present invention to obtain roasted coffee beans (hereinafter also referred to as "the method for producing roasted coffee beans of the present invention"); [3] Roasted coffee beans produced by the method for producing roasted coffee beans of the present invention (hereinafter also referred to as "roasted coffee beans of the present invention"); [4] Coffee extract obtained by extracting the ground roasted coffee beans of the present invention with water (hereinafter also referred to as "coffee extract of the present invention"); [5] A packaged coffee beverage containing the coffee extract of the present invention (hereinafter also referred to as "the packaged coffee beverage of the present invention"); and [6] A method for suppressing off-flavors in a coffee beverage produced from roasted coffee beans, comprising: Step A, fermenting coffee cherry pulp with microorganisms; Step B, mixing the coffee cherry pulp fermented in Step A with green coffee beans or coffee cherries and fermenting it to obtain coffee beans for roasting; and Step C, roasting the coffee beans for roasting obtained in Step B to obtain roasted coffee beans (hereinafter also referred to as "the method for suppressing off-flavors of the present invention"). This includes embodiments such as the following.

[0012] (Coffee Cherry) A coffee cherry is the fruit of the coffee plant. In terms of structure, a coffee cherry generally consists of the outer layer (exocarp), the pulp (containing sugars and other nutrients), and the green coffee bean (seed). More specifically, it consists of the outer layer (exocarp), the pulp, the endocarp (parchment), the silverskin, and the green coffee bean (seed).

[0013] There are no particular limitations on the varieties of coffee cherries or green coffee beans used, and examples include Arabica, Robusta, Arabusta, Liberica, etc. Examples of coffee bean varieties obtained by further subdividing Arabica or Robusta include Typica, Sumatra, Mundo Novo, Acaiá, Kent, Maragogipe, Bourbon, Caturra, Catuai, Amarello, Conilon, Uganda, etc. A blend of multiple types of coffee cherries or green coffee beans may also be used.

[0014] There are no particular limitations on the production areas of the coffee cherries or green coffee beans used, and examples include Brazil, Vietnam, Colombia, India, Honduras, Peru, Mexico, Guatemala, Costa Rica, Tanzania, Kenya, Yemen, Ethiopia, Indonesia, Jamaica, Hawaii, etc.

[0015] (Microorganisms) There are no particular limitations on the microorganisms used in the present invention, so long as they can be used for producing coffee beverages with the aforementioned off-flavor suppressed when used in the present invention, and preferred examples include lactic acid bacteria, Aspergillus oryzae, yeast, etc.

[0016] Examples of the aforementioned lactic acid bacteria include bacteria of the genus *Lactobacillus*, bacteria of the genus *Streptococcus*, bacteria of the genus *Lactococcus*, bacteria of the genus *Leuconostoc*, bacteria of the genus *Pediococcus*, and bacteria of the genus *Enterococcus*. Among these, bacteria of the genus *Lactobacillus* and bacteria of the genus *Streptococcus* are preferred. These lactic acid bacteria may be used singly or in combination. Furthermore, as lactic acid bacteria, more specifically, Lactobacillus acidophilus, Lactobacillus delbrueckii subsp. bulgaricus (hereinafter also simply referred to as "Lactobacillus bulgaricus"), Lactobacillus delbrueckii subsp. delbrueckii, Lactobacillus delbrueckii subsp. lactis, Lactobacillus casei, Lactobacillus paracasei, Lactobacillus gasseri, and Lactobacillus helveticus Lactobacillus helveticus), Lactobacillus johnsonii, Lactobacillus plantarum, Lactobacillus brevis, Lactobacillus casei subsp. rhamnosus, Lactobacillus pentosus, Lactobacillus fermentum, Streptococcus salivarius subsp. thermophilus (hereinafter also simply referred to as "Streptococcus thermophilus"), Lactococcus lactis subsp. Lactococcus lactis (hereinafter also simply referred to as "Lactococcus lactis"), Lactococcus lactis biovariant diacetylactis (Lactococcus lactis subsp.lactis biovar diacetylactis), *Lactococcus lactis* subsp. *cremoris*, *Lactococcus raffinolactis*, *Lactococcus piscium*, *Lactococcus plantarum*, *Lactococcus garvieae*, *Lactococcus lactis* subsp. *hordniae*, *Leuconostoc mesenteroides* subsp. *cremoris*, *Leuconostoc lactis*, *Pediococcus damnosus*, *Pediococcus pentosaceus*, *Pediococcus acidilactici*, *Enterococcus faecalis*, and *Enterococcus faecium*, and among these, one or two lactic acid bacteria selected from the group consisting of *Lactobacillus bulgaricus* and *Streptococcus thermophilus* are preferably mentioned..

[0017] The above-mentioned molds include, for example, Aspergillus oryzae, Aspergillus sojae, and Aspergillus tamari, which are used in the production of fermented foods such as brewed and distilled alcoholic beverages, miso, and soy sauce. Aspergillus oryzae is a microorganism involved in koji fermentation. Aspergillus oryzae belongs to the genus Aspergillus, and examples include Aspergillus koji, Aspergillus koji, and Aspergillus koji, with Aspergillus koji being preferred. Examples of Aspergillus koji include Aspergillus oryzae, Aspergillus sojae, and Aspergillus tamari, as an example of Aspergillus koji, Aspergillus kawachii, and Aspergillus koji. These molds, such as Aspergillus oryzae, may be used individually or in combination.

[0018] Examples of the yeasts mentioned above include brewing yeasts used in the production of alcoholic beverages such as wine or beer, including wine fermentation yeasts, beer fermentation yeasts, and sake fermentation yeasts. More specifically, examples of the yeasts mentioned above include Saccharomyces yeasts, Kluyveromyces yeasts, and Torulaspora yeasts, with Saccharomyces yeasts being particularly preferred. These lactic acid bacteria may be used individually or in combination. Examples of Saccharomyces yeasts include Saccharomyces cerevisiae and Saccharomyces pastorianus; examples of Kluyveromyces yeasts include Kluyveromyces thermotolerans; and examples of Torulaspora yeasts include Torulaspora delbrueckii. These yeasts may be used individually or in combination.

[0019] (Process A) Step A is not particularly limited as long as it is a step in which coffee cherry pulp is fermented with microorganisms. For example, one method is to ferment the coffee cherry pulp while it is in contact with the microorganisms. Preferably, one method is to mix the coffee cherry pulp with the microorganisms and then ferment the coffee cherry pulp.

[0020] The coffee cherry pulp used is not particularly limited as long as it contains coffee cherry pulp, and may consist solely of coffee cherry pulp, or it may further contain other materials besides coffee cherry pulp. Examples of such other materials include the exocarp, endocarp, silver skin, etc., which are derived from coffee cherries and not from the green coffee beans. In addition, additives such as pH adjusters, or commercially available nutrient media to supplement nitrogen and carbon sources may be added to the coffee cherry pulp as needed. The coffee cherry pulp can be, for example, obtained when separating green coffee beans from coffee cherries during the refining process.

[0021] The coffee cherry pulp used in step A may be unsterilized coffee cherry pulp, but it is preferable to use sterilized coffee cherry pulp from the viewpoint of obtaining a higher inhibitory effect on off-flavors. Sterilization by steam is preferred as such sterilization. The time for steam sterilization is, for example, 1 to 10 minutes, and preferably 2 to 8 minutes.

[0022] The fermentation conditions in step A are not particularly limited as long as conditions are suitable for fermentation, and suitable conditions for fermentation (for example, the type of microorganism used, its quantity (initial number), temperature, humidity, pH, oxygen or carbon dioxide concentration, fermentation time, etc.) can be set as needed. For example, such fermentation conditions include fermentation at 18-45°C (preferably 25-40°C) and in an atmosphere with a humidity of 50% or more for 5 hours to 3 days (preferably 10-24 hours). Furthermore, when fermenting coffee cherry pulp and microorganisms, it is preferable to ferment the mixture of coffee cherry pulp and microorganisms while wrapped in a cloth moistened with water. Furthermore, the quantity of microorganisms used in the fermentation in step A (initial number) is not particularly limited, but for example, 0.01-50g (dry weight), preferably 0.1-30g (dry weight), of microorganisms per 1kg of coffee cherry pulp is possible.

[0023] (Process B) Process B is not particularly limited as long as it is a process in which the coffee cherry pulp fermented in process A is mixed with green coffee beans or coffee cherries and fermented to obtain coffee beans for roasting.

[0024] In process B, "green coffee beans" refers to coffee cherries from which at least the outer skin and pulp have been removed, and includes green coffee beans; green coffee beans covered with silver skin; green coffee beans covered with endocarp and silver skin; etc. The aforementioned "green coffee beans covered with endocarp and silver skin" may have mucilage (a viscous liquid containing sugar) attached to their surface. "Green coffee beans covered with endocarp and silver skin" obtained when the outer skin and pulp are removed from coffee cherries usually have mucilage attached.

[0025] The variety and origin of the "green coffee beans or coffee cherries" used in step B may be the same as, or different from, the variety and origin of, the coffee cherry pulp used in step A.

[0026] The fermentation conditions in step B are not particularly limited as long as conditions are suitable for fermentation, and suitable conditions for fermentation (for example, the type of microorganism used, its quantity (initial number), temperature, humidity, pH, oxygen or carbon dioxide concentration, fermentation time, etc.) can be set as needed. For example, such fermentation conditions include fermentation at 15-40°C (preferably 20-40°C) and in an atmosphere of 30% or higher humidity for 1-12 days (preferably 3-9 days). As for the oxygen concentration, for example, it may be an aerobic or anaerobic condition, but anaerobic conditions are preferred when lactic acid bacteria are used as microorganisms, and aerobic conditions are preferred when koji mold is used. Examples of the aforementioned anaerobic conditions include sealing the "coffee cherry pulp fermented in step A" and "green coffee beans or coffee cherries" in a container such as a plastic bag, and immersing the "coffee cherry pulp fermented in step A" and "green coffee beans or coffee cherries" in water. Furthermore, the amount of "coffee cherry pulp fermented in step A" used in step B is not particularly limited as long as the "green coffee beans or coffee cherries" can be fermented by the microorganisms contained in the "coffee cherry pulp fermented in step A". For example, per 1 kg of such coffee cherry pulp, the amount of "green coffee beans or coffee cherries" can range from 10 g to 100 kg, preferably 30 g to 30 kg, more preferably 100 g to 10 kg, even more preferably 250 g to 4 kg, and more preferably 500 g to 2 kg.

[0027] The fermentation process in step B can be completed by performing the following processes individually or in any combination: washing the "green coffee beans or coffee cherries" with water to remove coffee cherry pulp and attached microorganisms; drying the "green coffee beans or coffee cherries" using a dryer or sun-drying; sterilizing the microorganisms by heat; and roasting the green coffee beans. For example, when drying the coffee fruit using a dryer, the fermentation process can be completed by drying at 50-60°C for 1-3 days. Specifically, for drying the "green coffee beans or coffee cherries," it is preferable to use a dryer at 50-60°C to dry the "green coffee beans or coffee cherries" to a moisture content of 10-30% by weight, and then sun-drying.

[0028] (Coffee beans for roasting according to the present invention) The roasting coffee beans of the present invention can be produced by a method for producing roasting coffee beans of the present invention, which includes step A of fermenting coffee cherry pulp with microorganisms, and step B of mixing the coffee cherry pulp fermented in step A with green coffee beans or coffee cherries and fermenting it to obtain roasting coffee beans. The coffee cherries obtained in step B can then be separated by washing away the microorganisms with water or the like, or by removing the pulp and hulling the cherries in a normal refining process while the microorganisms remain attached, thereby separating the green coffee beans.

[0029] (Process C) Step C is not particularly limited as long as it is a step of roasting coffee beans produced by the method for producing roasted coffee beans of the present invention (roasted coffee beans of the present invention) to obtain roasted coffee beans.

[0030] The roasting method described above is not particularly limited, and methods commonly used for roasting coffee beans, such as direct-fire roasting, hot-air roasting, far-infrared roasting, charcoal roasting, and microwave roasting, can be used. There are also no particular restrictions on roasting temperature or degree of roasting. Examples of roasting degrees include L values ​​of 15-45 and L values ​​of 18-25. The L value, which represents the degree of roasting of roasted coffee beans, can be measured using a colorimeter. For example, the PF 7000 spectrophotometer / colorimeter manufactured by Nippon Denshoku Industries Ltd. can be used.

[0031] (Roasted coffee beans of the present invention) The roasted coffee beans of the present invention can be produced by a method for producing roasted coffee beans, which includes step C of roasting coffee beans produced by the method for producing roasted coffee beans of the present invention.

[0032] (Coffee extract of the present invention) The coffee extract of the present invention can be obtained by extracting the ground roasted coffee beans of the present invention with water. The water used may be heated water.

[0033] Roasted coffee beans can be ground using a general-purpose grinder such as a roll mill. The grinding degree is not particularly limited, and roasted coffee beans of various grind sizes, such as coarse, medium-coarse, medium, medium-fine, and fine, can be used.

[0034] The method for extracting the ground roasted coffee beans of the present invention with water is not particularly limited and can be carried out using any general method used for extracting soluble solids from ground roasted coffee beans. Specifically, it can be done using any of the following methods: drip method, espresso method, siphon method, percolator method, coffee press (French press) method, high-pressure extraction, continuous high-pressure extraction, etc. Furthermore, the coffee extract of the present invention may be a coffee extract obtained by extracting the ground roasted coffee beans of the present invention with water, drying it to extract the essence, and then adding water to the extract. Alternatively, the coffee extract of the present invention may be obtained by concentrating or further diluting the coffee extract obtained by extracting the ground roasted coffee beans of the present invention with water. The aforementioned concentration method can be carried out by commonly used concentration methods such as thermal concentration, cryogenic concentration, or membrane concentration using reverse osmosis membranes or ultrafiltration membranes.

[0035] (The present invention: a packaged coffee beverage) The containerized coffee beverage of the present invention is not particularly limited as long as it contains the coffee extract of the present invention. The containerized coffee beverage of the present invention may or may not contain any other optional components besides the coffee extract of the present invention.

[0036] The optional ingredients mentioned above may include one or more additives such as sweeteners, milk components, antioxidants, flavorings, organic acids, organic acid salts, inorganic acids, inorganic acid salts, inorganic salts, colorants, emulsifiers, preservatives, seasonings, acidulants, amino acids, pH adjusters, and quality stabilizers. The packaged coffee beverage of the present invention can also be a black coffee beverage or a milk coffee beverage.

[0037] When manufacturing the packaged coffee beverage of the present invention, the amount of roasted coffee beans used per 100g of coffee beverage is preferably 1g or more, more preferably 2.5g or more, and even more preferably 4.5g or more, in terms of green beans. The upper limit of the amount of roasted coffee beans used per 100g of coffee beverage can be appropriately selected based on palatability, but from the viewpoint of flavor balance, it is preferably 20g or less, more preferably 15g or less, and even more preferably 10g or less, in terms of green beans. Here, the green bean equivalent value is assumed to be 1g of roasted coffee beans equivalent to 1.3g of green coffee beans (Revised New Edition, Soft Drinks, supervised by: Japan Soft Drink Association, published by: Korin, December 25, 1989, p. 421).

[0038] The packaged coffee beverage of the present invention can be manufactured by filling a coffee beverage into a container. Suitable containers include conventional packaging containers such as molded containers primarily made of polyethylene terephthalate (so-called PET bottles), metal cans, paper containers composited with metal foil or plastic film, and glass bottles.

[0039] The packaged coffee beverage of the present invention may be heat-sterilized. The heat sterilization method is not particularly limited as long as it conforms to the conditions stipulated in the applicable laws and regulations (Food Sanitation Law in Japan). Examples include retort sterilization, high-temperature short-time sterilization (HTST), and ultra-high temperature sterilization (UHT). Furthermore, the heat sterilization method can be appropriately selected depending on the type of container. For example, in cases where the beverage can be filled into a container and then heat-sterilized together with the container, such as in metal cans, retort sterilization can be used. For containers that cannot be retort-sterilized, such as PET bottles and paper containers, aseptic filling, in which the beverage is heat-sterilized in advance under sterilization conditions equivalent to those described above and then filled into a container sterilized in a sterile environment, or hot-pack filling can be used.

[0040] (Method for suppressing off-flavors according to the present invention) The present invention provides a method for suppressing off-flavors, and is not particularly limited as long as it includes a step A of fermenting coffee cherry pulp with microorganisms; a step B of mixing the coffee cherry pulp fermented in step A with green coffee beans or coffee cherries and fermenting it to obtain coffee beans for roasting; and a step C of roasting the coffee beans for roasting obtained in step B to obtain roasted coffee beans.

[0041] (Packaged coffee beverage with suppressed off-flavors) In this specification, "off-flavors derived from the coffee bean refining process" refers to off-flavors that occur when a coffee beverage is produced from the coffee beans during the above-mentioned coffee bean refining process (drying or fermentation) due to spoilage by environmental bacteria during drying or fermentation. Specifically, it refers to one or more off-flavors selected from the group consisting of a raw smell, a moldy smell, a lingering bitterness, a lingering off-flavor, and a slightly pungent burnt aroma.

[0042] The containerized coffee beverage of the present invention is a containerized coffee beverage in which the above-mentioned off-flavors are suppressed. In this specification, a containerized coffee beverage in which off-flavors are suppressed means a containerized coffee beverage in which the above-mentioned off-flavors are suppressed compared to a containerized coffee beverage manufactured using the same raw materials and the same manufacturing method, except that coffee cherry pulp that has been pre-fermented with microorganisms is mixed with "green coffee beans or coffee cherries" and fermented (hereinafter also referred to as "the control beverage in the present invention"). More specifically, examples of the above-mentioned control beverage include the coffee beverages of Comparative Example 1 and Comparative Example 2 in the examples described later.

[0043] A trained panelist can easily and clearly determine how off-flavors in a given containerized coffee beverage compare to (e.g., whether they are suppressed) the off-flavors in the control beverage according to the present invention.

[0044] Furthermore, according to the present invention, in addition to suppressing the off-flavors mentioned above, a good aroma is imparted. Such a good aroma tends to differ depending on the type of microorganism used, and the type of microorganism used can be appropriately selected according to the desired aroma. For example, using black koji (preferably Aspergillus luchuensis) can increase the coffee flavor, and using lactic acid bacteria (preferably Lactobacillus bulgaricus and / or Streptococcus thermophilus) can increase the vibrancy, liquor-like quality, and acidity. A trained panelist can easily and clearly determine how these aromas, other than off-flavors, in a given containerized coffee beverage compare to the aromas in the control beverage according to the present invention.

[0045] (Preferred embodiment of the method for producing roasted coffee beans according to the present invention) Preferred embodiments of the method for producing roasted coffee beans according to the present invention include the following embodiments p and q. Embodiment p: A method for producing coffee beans for roasting, comprising: step A, fermenting coffee cherry pulp with Aspergillus ruchuensis; and step B, mixing the coffee cherry pulp fermented in step A with green coffee beans or coffee cherries (preferably coffee cherries) and fermenting under aerobic conditions to obtain coffee beans for roasting. Embodiment q: A method for producing coffee beans for roasting, comprising: Step A: fermenting coffee cherry pulp with lactic acid bacteria (preferably Lactobacillus bulgaricus and / or Streptococcus thermophilus); and Step B: mixing the coffee cherry pulp fermented in Step A with green coffee beans or coffee cherries (preferably green coffee beans with mucilage attached to their surface), fermenting under anaerobic conditions (for example, sealed anaerobic conditions, or immersed in water and sealed anaerobic conditions), and then drying to obtain coffee beans for roasting.

[0046] The present invention will be described in detail below with reference to examples, but the present invention is not limited to these examples. [Examples]

[0047] [1. Preparation of coffee beans for roasting] Five types of roasted coffee beans (Comparative Example 1, Comparative Example 2, Example 1, Example 2, Example 3) were prepared using the following five preparation methods.

[0048] (1) Comparative Example 1; (Natural) Mature Yellow Bourbon coffee cherries grown domestically were harvested. After sun-drying the coffee cherries, the hulls were removed to obtain the roasting green coffee beans of Comparative Example 1.

[0049] (2) Comparative Example 2; (Washed, Anaerobic Fermentation) Mature Yellow Bourbon coffee cherries grown domestically were harvested. The pulp of the coffee cherries was removed, and the green coffee beans, with the mucilage (a viscous liquid containing sugar) visible on the surface, were packed into a food-grade plastic bag. The bag was then filled with water to create an anaerobic environment, and the beans were left to ferment in the shade at 25°C for 6 days. After fermentation, the green coffee beans were dried in a 50°C dryer until the moisture content reached 20% by weight, then sun-dried. Subsequently, the hulls were removed to obtain the green coffee beans for roasting, as shown in Comparative Example 2.

[0050] (3) Example 1; (Natural, Aerobic Fermentation, Koji) Mature Yellow Bourbon coffee cherries grown domestically were harvested. The pulp was obtained from these coffee cherries using a pulp removal machine. After washing the pulp with water, it was steam-treated for 5 minutes to sterilize any fungi attached to it. On the other hand, black koji (Aspergillus ruchuensis) was grown on sake rice, and then dried to obtain black koji starter. To 1 kg of the sterilized coffee cherry pulp mentioned above, 18 g of the aforementioned black koji starter culture was added and mixed in. The coffee cherry pulp mixed with black koji was wrapped in a water-soaked cloth and pre-fermented at 35°C for 18 hours.

[0051] Separately harvested mature coffee cherries (domestically grown Yellow Bourbon variety) were mixed with the aforementioned pre-fermented coffee cherry pulp in a 1:1 mass ratio, and the mixture was left to ferment in the shade at 25°C for 6 days. After fermentation, the coffee cherries were sun-dried, then hulled to remove the outer skin, pulp, mucilage, inner skin, and silvery skin, obtaining the roasting coffee beans of Example 1.

[0052] (4) Example 2; (Washed, anaerobic fermentation, lactic acid bacteria) Mature Yellow Bourbon coffee cherries grown domestically were harvested. Coffee cherry pulp was obtained from these cherries using a pulp removal machine. After washing the coffee cherry pulp with water, it was steam-treated for 5 minutes to sterilize any fungi attached to it. 100g of yogurt containing lactic acid bacteria (Lactobacillus bulgaricus and Streptococcus thermophilus) (100g of yogurt contains at least 0.01g of Lactobacillus bulgaricus and at least 0.1g of Streptococcus thermophilus by dry weight) was added to 1kg of sterilized coffee cherry pulp and mixed in. The coffee cherry pulp mixed with yogurt was wrapped in a water-soaked cloth and pre-fermented at 35°C for 18 hours.

[0053] After harvesting, mature coffee cherries (domestically grown Yellow Bourbon variety) were peeled, and the mucilage was exposed on the surface of the coffee beans. These beans were then mixed with the pre-fermented coffee cherry pulp in a 1:1 mass ratio, packed into food-grade plastic bags, and left in an anaerobic environment for 6 days at 25°C in the shade to ferment the green coffee beans. The fermented green coffee beans were dried in a 50°C dryer until the moisture content reached 20% by weight, then sun-dried. After that, the hulls were removed to remove the inner pericarp and silvery skin, yielding the green coffee beans for roasting in Example 2.

[0054] (5) Example 3; (Washed, anaerobic fermentation (in water), lactic acid bacteria) Mature Yellow Bourbon coffee cherries grown domestically were harvested. Coffee cherry pulp was obtained from these cherries using a pulp removal machine. After washing the coffee cherry pulp with water, it was steam-treated for 5 minutes to sterilize any fungi attached to it. 100g of yogurt containing lactic acid bacteria (Lactobacillus bulgaricus and Streptococcus thermophilus) (100g of yogurt contains at least 0.01g of Lactobacillus bulgaricus and at least 0.1g of Streptococcus thermophilus by dry weight) was added to 1kg of sterilized coffee cherry pulp and mixed in. The coffee cherry pulp mixed with yogurt was wrapped in a water-soaked cloth and pre-fermented at 35°C for 18 hours.

[0055] After harvesting, mature coffee cherries (domestically grown Yellow Bourbon variety) were peeled, and the mucilage was exposed on the surface of the green coffee beans. These beans were then mixed with the pre-fermented coffee cherry pulp in a 1:1 mass ratio, packed into a food-grade plastic bag, filled with water to create an anaerobic environment, and left to ferment in the shade at 25°C for 6 days. The fermented green coffee beans were dried in a 50°C dryer until the moisture content reached 20% by weight, then sun-dried. After that, the hulls were removed to remove the inner pericarp and silvery skin, yielding the green coffee beans for roasting described in Example 3.

[0056] Table 1 shows the main differences in the preparation methods for roasted coffee beans in Comparative Examples 1 and 2 and Examples 1 to 3.

[0057] [Table 1]

[0058] [2. Preparation of roasted coffee beans] The roasting coffee beans from Comparative Examples 1 and 2 and Examples 1 to 3 were each roasted until the L value reached 19, thereby preparing the roasted coffee beans for Comparative Examples 1 and 2 and Examples 1 to 3, respectively.

[0059] [3. Preparation of coffee beverages] The roasted coffee beans from Comparative Example 1 were ground. 30g of the ground roasted coffee beans were mixed with 450g of hot water, stirred 10 times, and allowed to stand for 5 minutes. After that, it was stirred 5 more times, and solid-liquid separation was performed using a paper filter. The resulting liquid was diluted with hot water until the °Bx reached 1.1, then filled into a container, sterilized, and the coffee beverage of Comparative Example 1 was prepared.

[0060] Using a similar method, coffee beverages for Comparative Example 2 and Examples 1-3 were prepared using the roasted coffee beans of Comparative Example 2 and Examples 1-3, respectively.

[0061] [4. Preparation of coffee beverages] Sensory evaluations of each coffee beverage were conducted by 5-7 trained panelists, using the evaluation criteria in Table 3 for items A-C in Table 2, and the evaluation criteria in Table 4 for item D.

[0062] [Table 2]

[0063] [Table 3]

[0064] [Table 4]

[0065] Table 5 shows the results of sensory evaluations of items A to D for each coffee beverage in Comparative Examples 1 and 2, and Examples 1 to 3. Table 6 shows the flavor characteristics freely evaluated by sensory evaluation, not limited to items A to D.

[0066] [Table 5]

[0067] [Table 6]

[0068] Sensory evaluation results showed that when coffee cherry pulp pre-fermented with microorganisms was not mixed with coffee cherries and fermented (Comparative Examples 1 and 2), off-flavors were present (Tables 5 and 6). In contrast, when coffee cherry pulp pre-fermented with microorganisms was mixed with coffee cherries and fermented (Examples 1-3), it was shown that off-flavors originating from the coffee bean refining process could be effectively suppressed in the coffee beverage.

[0069] Furthermore, in the method of the present invention, in which coffee cherry pulp pre-fermented with microorganisms is mixed with green coffee beans or coffee cherries and fermented, when black koji was used as the main fermenting agent (Example 1), the coffee flavor in the coffee beverage increased. On the other hand, when lactic acid bacteria were used as the main fermenting agent in the method of the present invention (Examples 2 and 3), the "fragrance / alcoholic feel" and "acidity" in the coffee beverage increased. These results indicate that, according to the present invention, in addition to suppressing off-flavors derived from the refining process of green coffee beans, a good aroma and flavor are imparted. [Industrial applicability]

[0070] According to the present invention, it is possible to provide a method for producing roasted coffee beans that can be used in the production of a packaged coffee beverage in which off-flavors derived from the refining process of green coffee beans are suppressed, a method for producing roasted coffee beans using such roasted coffee beans, a coffee extract obtained using such roasted coffee beans, and a packaged coffee beverage containing such coffee extract.

Claims

1. Step A of fermenting sterilized coffee cherry pulp with microorganisms; and, Step B involves mixing the coffee cherry pulp fermented in Step A with green coffee beans or coffee cherries and fermenting it to obtain coffee beans for roasting; A method for producing coffee beans for roasting, including [the specified ingredient].

2. The method for producing a product according to claim 1, wherein the microorganism is lactic acid bacteria or koji mold.

3. The manufacturing method according to claim 1, wherein lactic acid bacteria are used as the microorganism and anaerobic fermentation is performed as the fermentation, or koji mold is used as the microorganism and aerobic fermentation is performed as the fermentation.

4. A method for producing roasted coffee beans, comprising step C of roasting coffee beans produced by the manufacturing method described in any one of claims 1 to 3 to obtain roasted coffee beans.

5. Roasted coffee beans produced by the manufacturing method of claim 4.

6. A coffee extract obtained by extracting the ground roasted coffee beans described in claim 5 with water.

7. A packaged coffee beverage comprising the coffee extract described in claim 6.

8. Step A: Fermenting sterilized coffee cherry pulp with microorganisms; Step B involves mixing the coffee cherry pulp fermented in step A with green coffee beans or coffee cherries and fermenting it to obtain coffee beans for roasting; and, Step C involves roasting the coffee beans obtained in Step B to obtain roasted coffee beans; including, A method for suppressing off-flavors in a coffee beverage produced from the aforementioned roasted coffee beans.

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