Coffee fresh fruit high-temperature fermentation solid microbial inoculum and preparation method thereof, and raw coffee beans and preparation method thereof

Abstract

The invention provides a coffee fresh fruit high-temperature fermentation solid microbial inoculum and a preparation method thereof, and green coffee beans and a preparation method thereof, and relates to the technical field of coffee bean production. The solid microbial agent for high-temperature fermentation of the fresh coffee fruits comprises the following raw materials: Debaryomyces hansenii YB1 bacteria, wheat flour, coffee pericarp powder, flaccid knotweed herb powder and yeast powder for making hard liquor, the solid microbial agent for high-temperature fermentation of the fresh coffee fruits can be used for high-temperature fermentation of the fresh coffee fruits, and compared with low-temperature fermentation and room-temperature fermentation, the processing time can be shortened, the processing efficiency can be improved, and the production cost can be reduced. The method is suitable for large-scale production of coffee beans, improves the quality stability of coffee beans in different batches, enhances the fragrance quality and fragrance amount of the coffee beans, and improves the fine product rate of coffee.

Description

Technical Field

[0001] The present application relates to the technical field of coffee bean production, and in particular to a solid bacterial agent for high-temperature fermentation of fresh coffee fruits and a preparation method thereof, and green coffee beans and a preparation method thereof. Background Art

[0002] Coffee primary processing refers to the process of making coffee beans from fresh coffee fruit. It is a key step in brewing coffee flavor and one of the core factors affecting the quality of coffee products. Coffee beans processed by different methods will have different flavors. The fermentation process of fresh coffee fruit can enhance the release of internal compounds, enhance the aroma quality and aroma volume of coffee beans, and improve the rate of high-quality coffee.

[0003] At present, high-value boutique coffee beans are mainly fermented anaerobically at low temperature or room temperature. The fermentation cycle is as long as 120-240 hours, the processing efficiency is low, and because it is natural fermentation, the quality of coffee beans between different batches is unstable and varies greatly, mainly because of the lack of microbial agents suitable for large-scale production.

[0004] Among the various existing coffee fruit processing technologies, there is no high-temperature fermentation technology for coffee fruit and no microbial agent suitable for high-temperature fermentation of coffee fruit. Summary of the invention

[0005] The purpose of the present application is to provide a solid bacterial agent for high-temperature fermentation of fresh coffee fruit and a preparation method thereof, green coffee beans and a preparation method thereof, in order to solve the problem that the existing fresh coffee fruit processing technology cannot perform high-temperature fermentation.

[0006] To achieve the above objectives, the present application provides a solid bacterial agent for high-temperature fermentation of fresh coffee fruits. The raw materials of the solid bacterial agent for high-temperature fermentation of fresh coffee fruits include a base material, a functional bacterial liquid and a Daqu powder. The base material includes, by mass, 1 part of wheat flour, 0.1 to 0.4 parts of coffee peel powder and 0.002 to 0.004 parts of Polygonum hydropiper powder; the functional bacterial liquid is a bacterial liquid of Debaryomyces hansenii YB1, the mass of the functional bacterial liquid is 8% to 10% of the mass of the base material, and the mass of the Daqu powder is 6% to 10% of the mass of the base material.

[0007] In some embodiments, the Daqu powder is obtained by crushing Daqu; the Daqu is made from wheat, and the Daqu should meet the following conditions: moisture ≤ 15%, acidity 0.6-2.2 (mmol / 10g); fermentation power 0.1-0.44 (g / 0.5g·72h); starch content 70-75 (g / 100g);

[0008] The number of YB1 bacteria in the functional bacterial solution is 3×10 5 / mL~8×10 7 Pieces / mL.

[0009] In some embodiments, the wheat flour is obtained by grinding moistened wheat through a 20-mesh sieve, the coffee peel powder is obtained by grinding dried coffee peel through a 20-mesh sieve, the hot polygonum ternata powder is obtained by grinding commercially available hot polygonum ternata through a 60-mesh sieve; and the Daqu powder is obtained by grinding commercially available Daqu that meets the requirements through a 20-mesh sieve.

[0010] The present application also provides a method for preparing the above-mentioned solid bacterial agent for high-temperature fermentation of fresh coffee fruits, comprising:

[0011] Mix the wheat flour, the coffee peel powder and the Polygonum hydropiper powder to obtain a base material;

[0012] Inoculating the functional bacterial liquid into the base material and adjusting the first moisture content to obtain a first mixed material through a first fermentation;

[0013] Mixing the fermented material with the Daqu powder and adjusting the second moisture content to obtain a second mixed material;

[0014] The second mixed material is subjected to koji making, second fermentation and aging to obtain the fresh coffee fruit high temperature fermentation solid bacterial agent.

[0015] In some embodiments, the first moisture content is 45% to 55%, and the first fermentation time is 36 to 48 hours;

[0016] In some embodiments, the second moisture content is 38% to 40%; the relative humidity of the second fermentation is 80% to 90%; and the aging time is 3 to 5 months.

[0017] The present application also provides a method for preparing green coffee beans, comprising adding 1% to 4% by mass of the above-mentioned solid inoculum for high-temperature fermentation of fresh coffee fruits to fresh coffee fruits for high-temperature fermentation to obtain the green coffee beans.

[0018] In some embodiments, the high temperature fermentation temperature is ≥40°C, and the high temperature fermentation time is 12 to 72 hours.

[0019] In some embodiments, the fresh coffee fruits are peeled to retain 20% to 70% of the coffee fruit peels;

[0020] When the central temperature of the fermented material is ≥40°C, maintain high temperature fermentation for 12 to 48 hours;

[0021] Alternatively, turn the pile over once after 24 hours of fermentation, and continue fermenting for 12 to 36 hours after the central temperature of the fermented material reaches ≥40°C.

[0022] In some embodiments, the fresh coffee cherries are not peeled;

[0023] When the central temperature of the fermented material is ≥40°C, maintain high temperature fermentation for 24 to 60 hours;

[0024] Alternatively, turn the pile over once after 24 hours of fermentation, and continue fermenting for 24 to 48 hours after the central temperature of the fermented material reaches ≥40°C.

[0025] In some embodiments, the solid inoculant obtained by high temperature fermentation of fresh coffee fruits is in powder form, and the solid inoculant obtained by high temperature fermentation of fresh coffee fruits is crushed and passed through a 40-mesh sieve to obtain bacterial powder.

[0026] In some embodiments, the fresh coffee cherries are put into a fermentation barrel for fermentation or piled into a pile for fermentation; the fermented material is provided with evenly distributed ventilation holes; the spacing between the ventilation holes is 10 to 15 cm.

[0027] In some embodiments, after the high temperature fermentation is completed, the process further includes: spreading the material out to dry in the sun, or drying with hot air at 35° C. to 40° C., until the moisture content of the coffee beans is 10% to 12%.

[0028] The present application also provides green coffee beans, which are prepared by the above-mentioned method for preparing green coffee beans.

[0029] Compared with the prior art, the beneficial effects of this application include:

[0030] The raw materials for preparing the solid inoculant for high-temperature fermentation of fresh coffee fruits provided in the present application include wheat flour, coffee peel powder, Polygonum hydropiper powder, Debaryomyces hansenii YB1 bacteria and Daqu powder. The solid inoculant for high-temperature fermentation of fresh coffee fruits can be used for high-temperature fermentation of fresh coffee fruits. Compared with low-temperature fermentation and room-temperature fermentation, the processing time can be shortened and the processing efficiency can be improved. The solid inoculant can be applied to large-scale production of coffee beans, improve the quality stability of coffee beans between different batches, enhance the aroma quality and aroma quantity of coffee beans, and increase the rate of high-quality coffee. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope of the present application.

[0032] Figure 1 A schematic diagram of a shape of a fermentation pile in the fresh coffee fruit fermentation process of the present application;

[0033] Figure 2 This is a schematic diagram of another shape of a fermentation pile in the fresh coffee fruit fermentation process of the present application;

[0034] Figure 3 It is a comparison chart of the fermentation time of Comparative Example 5 and Example 3. DETAILED DESCRIPTION

[0035] As used herein:

[0036] "Prepared from" is synonymous with "comprising." As used herein, the terms "comprising," "including," "having," "containing," or any other variation thereof, are intended to cover a non-exclusive inclusion. For example, a composition, process, method, article, or apparatus that comprises the listed elements is not necessarily limited to only those elements but may include other elements not expressly listed or inherent to such composition, process, method, article, or apparatus.

[0037] The conjunction "consisting of excludes any unspecified element, step, or component. If used in a claim, this phrase renders the claim closed-ended so that it does not include materials other than those described, except for conventional impurities associated therewith. When the phrase "consisting of" appears in a clause of the body of a claim rather than immediately following the subject matter, it limits only the elements described in that clause; other elements are not excluded from the claim as a whole.

[0038] When an amount, concentration, or other value or parameter is expressed as a range, a preferred range, or a range defined by a series of upper preferred values ​​and lower preferred values, this should be understood as specifically disclosing all ranges formed by any pairing of any range upper limit or preferred value with any range lower limit or preferred value, regardless of whether the range is disclosed separately. For example, when a range of "1 to 5" is disclosed, the described range should be interpreted as including ranges "1 to 4", "1 to 3", "1 to 2", "1 to 2 and 4 to 5", "1 to 3 and 5", etc. When a numerical range is described in this article, unless otherwise stated, the range is intended to include its end values ​​and all integers and fractions within the range.

[0039] In these examples, parts and percentages are by mass unless otherwise indicated.

[0040] "Parts by mass" refers to the basic unit of measurement for expressing the mass ratio of multiple components. 1 part can represent any unit mass, such as 1g or 2.689g. If we say that the mass of component A is a parts and the mass of component B is b parts, it means the ratio of the mass of component A to the mass of component B is a:b. Alternatively, it means that the mass of component A is aK and the mass of component B is bK (K is an arbitrary number, indicating a multiple factor). It should not be misunderstood that, unlike the mass parts, the sum of the mass of all components is not limited to 100 parts.

[0041] "And / or" is used to indicate that one or both of the stated situations may occur, for example, A and / or B includes (A and B) and (A or B).

[0042] The present application provides a solid bacterial agent for high-temperature fermentation of fresh coffee fruits. The raw materials of the solid bacterial agent for high-temperature fermentation of fresh coffee fruits include a base material, a functional bacterial liquid and a koji powder. The base material includes, by mass, 1 part of wheat flour, 0.1 to 0.4 parts of coffee peel powder and 0.002 to 0.004 parts of Polygonum hydropiper powder; the functional bacterial liquid is a bacterial liquid of Debaryomyces hansenii YB1, the mass of the functional bacterial liquid is 8% to 10% of the mass of the base material, and the mass of the koji powder is 6% to 10% of the mass of the base material.

[0043] Among them, Debaryomyces hansenii YB1 is a fragrance-producing microorganism previously discovered by the applicant, and the strain is disclosed in the patent document with patent authorization announcement number CN 104130954B.

[0044] Among them, the number of YB1 bacteria in the functional bacterial solution is 3×10 5 / mL~8×10 7 / mL, for example, 3×10 5 / mL, 7×10 5 / mL, 5×10 6 / mL, 9×10 6 / mL, 2×10 7 / mL, 6×10 7 / mL, 8×10 7 / mL or 3×10 5 / mL~8×10 7 The mass of the functional bacterial liquid can be 8%, 9%, 10% or any value between 8% and 10% of the mass of the base material.

[0045] The coffee husk powder may be, for example, 0.1 part, 0.2 part, 0.3 part, 0.4 part or any value between 0.1 and 0.4 part; the Polygonum hydropiper powder may be, for example, 0.002 part, 0.003 part, 0.004 part or any value between 0.002 and 0.004 part.

[0046] The mass of the Daqu powder can be 6%, 7%, 8%, 9%, 10% or any value between 6% and 10% of the mass of the base material.

[0047] In some embodiments, the Daqu powder is obtained by crushing the Daqu; the Daqu is made from wheat, and the moisture content of the Daqu is ≤15%, for example, it can be 15%, 14%, 13%, 12%, 11%, 10%, 8%, 5% or any value ≤15%; the acidity of the Daqu is 0.6-2.2 (mmol / 10g), for example, it can be 0.6 (mmol / 10g), 0.7 (mmol / 10g), 0.9 (mmol / 10g), 1.0 (mmol / 10g), 1.2 (mmol / 10g). l / 10g), 1.5 (mmol / 10g), 1.8 (mmol / 10g), 2.0 (mmol / 10g), 2.2 (mmol / 10g) or any value between 0.6 and 2.2 (mmol / 10g); the fermentation capacity is 0.1 to 0.44 (g / 0.5g·72h), for example, 0.1 (g / 0.5g·72h), 0.15 (g / 0.5g·72h), 0.18 (g / 0.5g·72h), 0.20 (g / 0.5g·72h), 2h), 0.22(g / 0.5g·72h), 0.25(g / 0.5g·72h), 0.27(g / 0.5g·72h), 0.29(g / 0.5g·72h), 0.30(g / 0.5g·72h), 0 .32(g / 0.5g·72h), 0.35(g / 0.5g·72h), 0.37(g / 0.5g·72h), 0.39(g / 0.5g·72h), 0.40(g / 0.5g·72h), 0.41(g / 0.5g·72h), 0.42 (g / 0.5g·72h), 0.44 (g / 0.5g·72h) or any value between 0.1 and 0.44 (g / 0.5g·72h); starch content 70 to 75 (g / 100g), for example, it can be 70 (g / 100g), 71 (g / 100g), 72 (g / 100g), 73 (g / 100g), 74 (g / 100g), 75 (g / 100g) or any value between 70 and 75 (g / 100g).

[0048] Among them, acidity, fermentation ability and starch content are defined in accordance with the General Analytical Method for Brewing Daqu QB / T4258-2011. The acidity is determined by potentiometric titration with acid-base neutralization and pH indicating the endpoint. The unit mmol / 10g means "the number of millimoles of 0.1mol / L sodium hydroxide standard solution consumed by 10g of sample". The fermentation ability unit g / 0.5g·72h means the number of grams of CO2 produced by 0.5g of Daqu using fermentable sugars at 30℃ within 72h.

[0049] In some embodiments, the wheat flour is obtained by grinding moistened wheat through a 20-mesh sieve, the coffee peel powder is obtained by grinding dried coffee peel through a 20-mesh sieve, the hot polygonum ternata powder is obtained by grinding commercially available hot polygonum ternata through a 60-mesh sieve; and the Daqu powder is obtained by grinding commercially available Daqu that meets the requirements through a 20-mesh sieve.

[0050] Among them, the wheat is ordinary commercially available wheat, and 5%-10% of the weight of the wheat is added with wheat-moistening water. After stirring evenly, it is left to stand for 4-6 hours to allow the wheat husk to fully absorb water and ensure that the wheat husk swells intact when crushed.

[0051] The present application also provides a method for preparing the above-mentioned solid bacterial agent for high-temperature fermentation of fresh coffee fruits, comprising:

[0052] Mix the wheat flour, the coffee peel powder and the Polygonum hydropiper powder to obtain a base material;

[0053] Inoculating the functional bacterial liquid into the base material and adjusting the first moisture content, and obtaining a first mixed material through a first fermentation;

[0054] Mixing the fermented material with the Daqu powder and adjusting the second moisture content to obtain a second mixed material;

[0055] The second mixed material is subjected to koji making, second fermentation and aging to obtain the high temperature fermentation solid bacterial agent.

[0056] In some embodiments, the first moisture content is 45% to 55%, for example, it can be 45%, 46%, 47%, 48%, 49%, 50%, 51%, 52%, 53%, 54%, 55% or any value between 45% and 55%, and the first fermentation time is 36 to 48h, for example, it can be 36h, 38h, 40h, 41h, 42h, 43h, 44h, 45h, 46h, 47h, 48h or any value between 36 and 48h.

[0057] In some embodiments, the second moisture content is 38% to 40%, for example, 38%, 39% or 40%; the relative humidity of the second fermentation is 80% to 90%, for example, 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89% or 90%; the aging time is 3 to 5 months, for example, 3 months, 3.5 months, 4 months, 4.5 months, 5 months or any time between 3 and 5 months.

[0058] The present application also provides a method for preparing green coffee beans, comprising adding 1% to 4% by mass of the above-mentioned solid inoculum for high-temperature fermentation of fresh coffee fruits to fresh coffee fruits for high-temperature fermentation to obtain the green coffee beans.

[0059] High temperature fermentation utilizes the rapid reproduction of microorganisms in solid bacterial agents to inhibit microorganisms in the environment. High temperature can then decompose the starch in the coffee beans, making the coffee sweeter after roasting.

[0060] The addition amount of the solid bacterial agent for high temperature fermentation of fresh coffee fruits can be, for example, 1%, 2%, 3%, 4% or any value between 1% and 4%.

[0061] In some embodiments, the high temperature fermentation temperature is ≥40°C, and the high temperature fermentation time is 12 to 72 hours.

[0062] In some embodiments, the fresh coffee fruits are peeled to retain 20% to 70% of the coffee fruit peels;

[0063] When the central temperature of the fermented material is ≥40°C, maintain high temperature fermentation for 12 to 48 hours;

[0064] Alternatively, turn the pile over once after 24 hours of fermentation, and continue fermenting for 12 to 36 hours after the central temperature of the fermented material reaches ≥40°C.

[0065] In some embodiments, the fresh coffee cherries are not peeled;

[0066] When the central temperature of the fermented material is ≥40°C, maintain high temperature fermentation for 24 to 60 hours;

[0067] Alternatively, turn the pile over once after 24 hours of fermentation, and continue fermenting for 24 to 48 hours after the central temperature of the fermented material reaches ≥40°C.

[0068] In some embodiments, the solid inoculant obtained by high temperature fermentation of fresh coffee fruits is in powder form, and the solid inoculant obtained by high temperature fermentation of fresh coffee fruits is crushed and passed through a 40-mesh sieve to obtain bacterial powder.

[0069] In some embodiments, the fresh coffee cherries are put into a fermentation barrel for fermentation or piled into a pile for fermentation; the fermented material is provided with evenly distributed ventilation holes; the spacing between the ventilation holes is 10 to 15 cm.

[0070] In some embodiments, after the high temperature fermentation is completed, the process further includes: spreading the material out to dry in the sun, or drying with hot air at 35° C. to 40° C., until the moisture content of the coffee beans is 10% to 12%.

[0071] The present application also provides green coffee beans, which are prepared by the above-mentioned method for preparing green coffee beans.

[0072] The embodiments of the present application will be described in detail below in conjunction with specific examples, but it will be appreciated by those skilled in the art that the following examples are only used to illustrate the present application and should not be considered as limiting the scope of the present application. If specific conditions are not specified in the examples, they are carried out according to normal conditions or the conditions recommended by the manufacturer. If the manufacturer is not specified for the reagents or instruments used, they are all conventional products that can be purchased commercially.

[0073] The method for culturing the functional bacterial solution used in this application comprises the following steps:

[0074] 1. Dilute the sugarcane molasses stock solution to 10 Brix, adjust the pH to 3.0 with hydrochloric acid, boil for 15 minutes, let stand for 10 hours, centrifuge to obtain the supernatant, add 0.24% KH2PO4, 0.15% MgSO4, 0.4% yeast extract, and 3.5% peptone to prepare the molasses dilution medium.

[0075] 2. Take a 250ml Erlenmeyer flask and add 60ml of molasses dilution medium to the flask, adjust the pH to 6.0, sterilize at 121℃ for 20min, cool to room temperature and inoculate Debaryomyces hansenii YB1 bacteria, culture on a shaking table for 30h, culture temperature at 30℃, rotation speed at 180rpm, to obtain a primary seed solution.

[0076] 3. Fill a 5L fermenter with 3L of molasses diluted medium, adjust the pH to 6.0, sterilize at 121℃ for 20min, cool to 30℃, inoculate with 5% volume ratio of first-level seed liquid, rotate at 50rpm, aerate at 90L / h, ferment for 30h to obtain second-level seed liquid.

[0077] 4. Fill a 50L fermenter with 30L of molasses diluted medium, adjust the pH to 6.0, sterilize at 121℃ for 20min, cool to 30℃, inoculate 8% volume ratio of secondary seed liquid, rotate at 50rpm, aerate at 200L / h, ferment for 36h to obtain functional bacterial liquid.

[0078] The preparation method of the solid inoculant of coffee fruit high temperature fermentation used in the following examples comprises the following steps:

[0079] (1) Moistening wheat: Soak the wheat in water at 70℃±5℃ for 4 hours, during which the water level should always be 3 to 4 cm higher than the wheat.

[0080] (2) Grinding: Grind the moistened wheat through a 20-mesh sieve and set aside. Grind the dried coffee husk through a 20-mesh sieve and set aside. Grind the hot pepper grass through a 60-mesh sieve and set aside.

[0081] (3) Mixing: Mix wheat: coffee peel powder: Polygonum hydropiper powder in a mass ratio of 1:0.1-0.4:0.002-0.004 to obtain a base material.

[0082] (4) Inoculating 8% of the functional bacterial liquid according to the weight of the base material, and adjusting the moisture content to 50%, performing the first fermentation for 40 hours to obtain a first mixed material.

[0083] (5) Add 6% of the total mass of the base material to the first mixed material, and adjust the moisture content to 38% to 40% to obtain a second mixed material.

[0084] (6) Koji making: After the second mixed material is stirred, a mechanical koji press is used to press a koji block of 270×180×50 mm in size to obtain a rectangular koji blank, which is then placed in a koji room.

[0085] (7) Second fermentation: A layer of 2-3 cm thick straw is laid on the floor of the koji room. The koji blocks are arranged on the straw with a distance of 3 cm between any two koji blocks. After the arrangement is completed, a layer of 2 cm straw is covered on the koji blocks and an appropriate amount of water is sprayed on the straw. The doors and windows are closed and the heat preservation and moisture preservation culture is started. The relative humidity is controlled at 80%-90%. When the product temperature reaches 40°C, the koji is turned for the first time, from the surrounding areas to the center; the fermentation continues for 4 days, and the second turning is carried out; the fermentation continues. If the product temperature is higher than 60°C, open the window to adjust the temperature; when most of the water in the center of the koji blocks evaporates and the product temperature gradually drops, the koji blocks are collected and composted, leaving no gaps between the koji blocks. When the temperature of the koji blocks drops to room temperature, the fermentation is completed.

[0086] (8) Storage and aging: Place the fermented koji blocks in a ventilated, dry, odor-free warehouse for aging, leaving a gap of about 0.5 cm between the koji blocks for ventilation. It can be used after 3 months of storage. Take the koji blocks that have been aged for 3 months and crush them through a 40-mesh sieve to obtain bacterial powder for later use.

[0087] The coffee fruit high temperature fermentation solid bacterial agent used in each embodiment is the same in preparation method except that the ratio of raw materials wheat, coffee peel powder and hot Polygonum salsa powder is different, wherein the mass ratio of wheat, coffee peel powder and hot Polygonum salsa powder in bacterial powder (1) is 1 part: 0.1 part: 0.002 part; the mass ratio of wheat, coffee peel powder and hot Polygonum salsa powder in bacterial powder (2) is 1 part: 0.3 part: 0.003 part; the mass ratio of wheat, coffee peel powder and hot Polygonum salsa powder in bacterial powder (3) is 1 part: 0.4 part: 0.004 part.

[0088] Example 1

[0089] This embodiment provides a method for preparing green coffee beans, which includes the following steps:

[0090] Pick ripe Robusta coffee (Coffea canephora) coffee berries, remove shrunken berries, floating berries, branches and leaves and other impurities by water selection, remove and drain the surface moisture, use an anhydrous coffee peeling machine to remove 80% of the berries and retain 20% of the berries. Weigh 150 kg of fresh coffee berries and add 2% of its weight of bacterial powder (1). After mixing, put them into a clean, breathable and odorless fermentation barrel and place them in a dry and ventilated room for fermentation. After the temperature of the pile core rises to 40°C, continue to ferment for 48 hours. After the fermentation is completed, spread them out in the sun until the moisture content of the coffee beans is 11% to 12%. Shell and grade them into green coffee beans.

[0091] Example 2

[0092] This embodiment provides a method for preparing green coffee beans, which includes the following steps:

[0093] Ripe Robusta coffee berries (Coffea canephora) are picked, and impurities such as shrunken berries, floating berries, branches and leaves are removed by water selection, and the surface moisture is drained. A waterless coffee peeling machine is used to remove 50% of the peel and retain 50% of the peel. 1000 kg of peeled coffee berries are weighed, and 4% of the weight of bacterial powder (2) is added. After mixing, the berries are placed on a clean, odorless, waterproof and moisture-proof plastic cloth to form a cylindrical fermentation pile for fermentation, with a pile height of 70 cm. The fermentation is carried out as follows: Figure 1 The method shown is to evenly make ventilation holes from the top to the bottom of the pile, with a pore spacing of 15 cm. After the temperature of the pile core reaches 40°C, ferment for 24 hours, turn the pile once, turn the coffee cherries on the surface of the pile to the inside of the pile, and pile up again to continue fermentation. After the temperature of the pile core reaches 40°C, continue fermentation for 24 hours, and cover the surface of the pile with a clean and breathable insulation blanket. After the fermentation is completed, use 38°C hot air to dry the coffee beans until the moisture content is 11% to 12%, and then shell and grade them into green coffee beans.

[0094] Example 3

[0095] This embodiment provides a method for preparing green coffee beans, which includes the following steps:

[0096] Ripe Arabica coffee berries are picked, and impurities such as shrunken berries, floating berries, branches and leaves are removed by water selection. The surface moisture is drained, and 40% of the berries are removed by a waterless coffee peeling machine, and 60% of the berries are retained. 100 kg of peeled coffee berries are weighed, and 3% of the bacterial powder (3) is added to the berries. After mixing, the berries are placed in a clean, breathable and odorless rectangular fermentation basket, and the mixture is stirred for 10 minutes. Figure 2 The method shown is to evenly punch small air holes from top to bottom with a spacing of 10 cm between the air holes, place the fermentation basket in a dry and ventilated room, and use a clean and breathable insulation blanket around the fermentation basket. After the temperature of the pile core rises to 40°C, continue to ferment for 36 hours. After the fermentation is completed, spread out in the sun until the moisture content of the coffee beans is 11% to 12%. Shelling and grading into green coffee beans.

[0097] Example 4

[0098] This embodiment provides a method for preparing green coffee beans, which includes the following steps:

[0099] Ripe Arabica coffee berries are picked, and impurities such as shrunken berries, floating berries, branches and leaves are removed by water selection. The berries are fished out and the surface moisture is drained. A waterless coffee peeling machine is used to remove 45% of the berries and 55% of the berries are retained. 1500 kg of peeled coffee berries are weighed, and 2.5% of the bacterial powder (1) is added to the berries. After mixing, the berries are placed on a clean, odorless, waterproof and moisture-proof plastic cloth to form a rectangular fermentation pile with a height of 100 cm. The fermentation is carried out as follows: Figure 2 The method shown is to evenly make small air holes from the top to the bottom of the pile, with a spacing of 10 cm between the holes. After the temperature at the center of the pile reaches 40°C, the fermentation is continued for 30 hours, and the surface of the pile is covered with a clean, breathable insulation blanket. After the fermentation is completed, the coffee beans are dried with 35°C hot air until the moisture content is 11% to 12%. The beans are shelled and graded into green coffee beans.

[0100] Example 5

[0101] This embodiment provides a method for preparing green coffee beans, which includes the following steps:

[0102] Ripe Robusta coffee berries (Coffea canephora) are picked, and impurities such as shrunken berries, floating berries, branches and leaves are removed by water selection. After the surface moisture is drained, 100 kg of coffee berries are weighed, 1% of the weight of the bacterial powder (2) is added, and after mixing, the berries are packed into a clean, breathable and odorless nylon bag, and placed in a dry and ventilated room for fermentation. After the temperature of the pile core rises to 40° C., the fermentation is continued for 48 hours. After the fermentation is completed, the coffee beans are spread out in the sun until the moisture content is 11% to 12%. The beans are shelled and graded into green coffee beans.

[0103] Example 6

[0104] This embodiment provides a method for preparing green coffee beans, which includes the following steps:

[0105] Ripe Robusta coffee berries (Coffea canephora) are picked, and impurities such as shrunken berries, floating berries, branches and leaves are removed by water selection. After the surface moisture is drained, 1000 kg of fresh coffee berries are weighed, 2% of the weight of the bacteria powder (2) is added, and after mixing, the berries are placed on a clean, odorless, waterproof and moisture-proof plastic cloth to form a rectangular fermentation pile for fermentation. The pile height is 110 cm, and the surface of the pile is covered with a clean, breathable insulation blanket. After the temperature of the pile core rises to 40° C., the fermentation is continued for 36 hours. After the fermentation is completed, the coffee beans are dried with 40° C. hot air until the moisture content is 11% to 12%. The beans are shelled and graded into green coffee beans.

[0106] Example 7

[0107] This embodiment provides a method for preparing green coffee beans, which includes the following steps:

[0108] Ripe Arabica coffee berries are picked, and impurities such as shrunken berries, floating berries, branches and leaves are removed by water selection. After the surface moisture is drained, 150 kg of coffee berries are weighed, 3% of the weight of the bacterial powder (3) is added, and after mixing, the berries are packed into a clean, breathable and odorless nylon bag, and placed in a dry and ventilated room for fermentation. After the temperature of the pile core rises to 40° C., the fermentation is continued for 36 hours. After the fermentation is completed, the coffee beans are spread out in the sun until the moisture content is 11% to 12%. The beans are shelled and graded into green coffee beans.

[0109] Example 8

[0110] This embodiment provides a method for preparing green coffee beans, which includes the following steps:

[0111] Pick ripe Arabica coffee berries, remove impurities such as shrunken berries, floating berries, branches and leaves by water selection, remove and drain the surface moisture, weigh 2000 kg of coffee berries, add 4% of its weight of bacterial powder (3), mix well and place on a clean and odorless waterproof and moisture-proof plastic cloth to form a cylindrical fermentation pile for fermentation, the pile height is 100 cm, and the surface of the pile is covered with a clean and breathable insulation blanket. After the temperature of the pile core rises to 40°C, continue to ferment for 48 hours. After the fermentation is completed, use 40°C hot air to dry the coffee beans until the moisture content is 11% to 12%. Shell and grade them into green coffee beans.

[0112] Comparative Example 1

[0113] This comparative example provides a green coffee bean, and the preparation method thereof comprises the following steps:

[0114] Ripe Arabica coffee berries are picked, and impurities such as shrunken berries, floating berries, branches and leaves are removed by water selection. The surface moisture is drained, and 50% of the berries are removed by a waterless coffee peeling machine, and 50% of the berries are retained. 200 kg of peeled coffee berries are weighed, and hot air is used to dry the berries at 40° C. until the moisture content of the coffee beans is 11% to 12%, and the berries are shelled to obtain raw coffee beans.

[0115] Comparative Example 2

[0116] This comparative example provides a green coffee bean, and the preparation method thereof comprises the following steps:

[0117] Pick ripe Arabica coffee berries, remove impurities such as shrunken berries, floating berries, branches and leaves by water selection, remove and drain the moisture on the skin, use an anhydrous coffee peeling machine to remove 50% of the peel and retain 50% of the peel, weigh 200kg of peeled coffee berries, add 2% of commercially available Daqu powder that meets the requirements and passes through a 20-mesh sieve, mix well and put into a clean, breathable and odorless rectangular fermentation basket, and press as follows Figure 2 The method shown is to evenly make small air holes from top to bottom with a spacing of 10 cm between the air holes, place the fermentation basket in a dry and ventilated room, and use a clean and breathable insulation blanket around the fermentation basket. After the temperature of the pile core rises to 40°C, continue to ferment for 36 hours. After the fermentation is completed, use 40°C hot air to dry the coffee beans until the moisture content is 11% to 12%. Shelling and grading into green coffee beans.

[0118] Comparative Example 3

[0119] This comparative example provides a green coffee bean, and the preparation method thereof comprises the following steps:

[0120] Ripe Arabica coffee berries are picked, and after using a water selection method to remove impurities such as shriveled berries, floating berries, branches and leaves, 200 kg of fresh coffee berries are weighed and directly exposed to the sun until the moisture content of the coffee beans is 11% to 12%.

[0121] Comparative Example 4

[0122] This comparative example provides a green coffee bean, and the preparation method thereof comprises the following steps:

[0123] Pick ripe Arabica coffee berries, remove impurities such as shrunken berries, floating berries, branches and leaves by water selection, remove and drain the surface moisture, weigh 2000kg of coffee berries, add 2% of commercially available Daqu powder that meets the requirements and passes through a 20-mesh sieve, mix well and place on a clean, odorless waterproof and moisture-proof plastic cloth to ferment in a cylindrical fermentation pile, with a pile height of 100cm, and cover the surface of the pile with a clean, breathable insulation blanket. After the temperature of the pile core rises to 40℃, continue to ferment for 48h. After the fermentation is completed, use 40℃ hot air to dry the coffee beans until the moisture content is 11% to 12%. Shell and grade into green coffee beans.

[0124] Comparative Example 5

[0125] This comparative example provides a green coffee bean, and the preparation method thereof comprises the following steps:

[0126] Ripe Arabica coffee berries are picked, and impurities such as shriveled berries, floating berries, branches and leaves are removed by water selection. After the surface moisture is drained, 40% of the berries are removed by a waterless coffee peeling machine, and 60% of the berries are retained. 100 kg of peeled coffee berries are loaded into a fermentation barrel and fermented anaerobically at room temperature for 240 hours. After the fermentation is completed, the berries are spread out in the sun until the moisture content of the coffee beans is in the range of 10% to 12%, and the berries are shelled to obtain green coffee beans.

[0127] Coffee bean roasting and cup sensory testing

[0128] The green coffee beans of each embodiment and comparative example were roasted and subjected to a cupping sensory test, respectively, and the roasting method was as follows:

[0129] Accurately weigh 500.0g of green coffee beans and pour them into the roaster. Set the power to 6.5, the air damper to 1.2, the pot temperature to 180℃, and the roasting time to 8 minutes to obtain medium roasted beans. Carry out the cupping sensory test according to the Specialty Coffee Association of America (SCA) cupping system.

[0130] The results of the cupping sensory indexes of the green coffee beans of the embodiments and comparative examples are shown in Tables 1 and 2. Table 1 shows the test results of the green coffee beans made from peeled fresh coffee fruits, and Table 2 shows the test results of the green coffee beans made from unpeeled fresh coffee fruits.

[0131] Table 1 Comparison of coffee cup quality after high temperature fermentation of peeled coffee fruit

[0132]

[0133] Table 2 Comparison of sensory indicators of coffee cups obtained by fermentation of unpeeled fresh coffee fruits

[0134]

[0135]

[0136] It can be seen from Table 1 and Table 2 that the coffee beans obtained by the high-temperature fermentation of fresh coffee fruits with solid inoculant in the present application have high body, good consistency and balance, harmonious aroma, sufficient aroma, high sweetness and aftertaste, and are significantly superior to the coffee beans processed by the prior art in all aspects of cup taste sensory perception, and are also superior to the coffee beans directly fermented with Daqu powder at high temperature.

[0137] Comparative Example 5 is a low-temperature anaerobic natural fermentation technology widely used in the production of fine coffee. The fermentation time is compared with that of Example 3. Figure 3 As shown, according to Figure 3 It can be seen that the use of the coffee fruit high-temperature fermentation solid bacterial agent of the present application for fermentation can greatly shorten the fermentation time compared to low-temperature anaerobic fermentation, thereby improving production efficiency and saving production costs.

[0138] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

[0139] In addition, those skilled in the art will appreciate that, although some embodiments herein include certain features included in other embodiments but not other features, the combination of features of different embodiments is meant to be within the scope of the present application and form different embodiments. For example, in the above claims, any one of the claimed embodiments may be used in any combination. The information disclosed in this background technology section is intended only to deepen the understanding of the overall background technology of the present application and should not be regarded as an admission or in any form of implication that the information constitutes prior art known to those skilled in the art.

Claims

1. A solid bacterial agent for high temperature fermentation of fresh coffee fruit, characterized in that: The raw materials of the solid bacterial agent for high-temperature fermentation of fresh coffee fruits include base material, functional bacterial liquid and Daqu powder. The base material includes, by mass, 1 part of wheat flour, 0.1-0.4 parts of coffee peel powder and 0.002-0.004 parts of Polygonum hydropiper powder; the functional bacterial liquid is the bacterial liquid of Debaryomyces hansenii YB1, the mass of the functional bacterial liquid is 8%-10% of the mass of the base material, and the mass of the Daqu powder is 6%-10% of the mass of the base material.

2. The high temperature fermentation solid bacterial agent according to claim 1, characterized in that: The Daqu powder is obtained by crushing Daqu; the Daqu is made from wheat, and the Daqu should meet the following conditions: moisture ≤ 15%, acidity 0.6-2.2 (mmol / 10g); fermentation power 0.1-0.44 (g / 0.5g·72h); starch content 70-75 (g / 100g); The number of YB1 bacteria in the functional bacterial solution is 3×10 5 / mL~8×10 7 Pieces / mL.

3. The high temperature fermentation solid bacterial agent according to claim 1, characterized in that: The wheat flour is obtained by grinding moistened wheat through a 20-mesh sieve, the coffee peel powder is obtained by grinding dried coffee peel through a 20-mesh sieve, the hot polygonum odoratum powder is obtained by grinding commercially available hot polygonum odoratum through a 60-mesh sieve; the Daqu powder is obtained by grinding commercially available Daqu that meets the conditions through a 20-mesh sieve.

4. A method for preparing a solid inoculant for high temperature fermentation of fresh coffee fruit as claimed in any one of claims 1 to 3, characterized in that: include: Mix the wheat flour, the coffee peel powder and the Polygonum hydropiper powder to obtain a base material; Inoculating the functional bacterial liquid into the base material and adjusting the first moisture content to obtain a first mixed material through a first fermentation; Mixing the fermented material with the Daqu powder and adjusting the second moisture content to obtain a second mixed material; The second mixed material is subjected to koji making, second fermentation and aging to obtain the fresh coffee fruit high temperature fermentation solid bacterial agent; Preferably, the first moisture content is 45% to 55%, and the first fermentation time is 36 to 48 hours; Preferably, the second moisture content is 38% to 40%; the relative humidity of the second fermentation is 80% to 90%; and the aging time is 3 to 5 months.

5. A method for preparing green coffee beans, characterized in that: The green coffee beans are obtained by adding 1% to 4% by mass of the solid bacterial agent for high-temperature fermentation of fresh coffee fruits as claimed in any one of claims 1 to 3 to fresh coffee fruits for high-temperature fermentation.

6. The method for preparing green coffee beans according to claim 5, characterized in that: The high temperature fermentation temperature is ≥40°C, and the high temperature fermentation time is 12 to 72 hours.

7. The method for preparing green coffee beans according to claim 6, characterized in that: The fresh coffee fruits are peeled to retain 20% to 70% of the coffee fruit peels; When the central temperature of the fermented material is ≥40°C, maintain high temperature fermentation for 12 to 48 hours; Alternatively, turn the pile over once after 24 hours of fermentation, and continue fermenting for 12 to 36 hours after the central temperature of the fermented material reaches ≥40°C.

8. The method for preparing green coffee beans according to claim 6, characterized in that: The fresh coffee berries are not peeled; When the central temperature of the fermented material is ≥40°C, maintain high temperature fermentation for 24 to 60 hours; Alternatively, turn the pile over once after 24 hours of fermentation, and continue fermenting for 24 to 48 hours after the central temperature of the fermented material reaches ≥40°C.

9. The method for preparing green coffee beans according to any one of claims 5 to 8, characterized in that: The solid bacterial agent fermented by high temperature of fresh coffee fruit is in powder form, and the solid bacterial agent fermented by high temperature of fresh coffee fruit is crushed and passed through a 40-mesh sieve to obtain bacterial powder; The fresh coffee berries are placed in a fermentation barrel for fermentation or piled into a pile for fermentation; the fermented material is provided with evenly distributed ventilation holes; the spacing between the ventilation holes is 10 to 15 cm; After the high temperature fermentation is finished, the method further includes: spreading the material out for sun exposure, or drying with hot air at 35° C. to 40° C., until the moisture content of the coffee beans is 10% to 12%.

10. A green coffee bean, characterized in that: Prepared by the method for preparing green coffee beans according to any one of claims 5 to 9.

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