A method for producing fermented coffee cultivated on grain solid mushroom mycelium seed

Abstract

To provide a method for producing fermented coffee and fermented coffee produced by said method. [Solution] To this end, the present invention is characterized in that the production method includes the steps of soaking green coffee beans in an extract, sterilizing the soaked green coffee beans and then cooling them, applying a cereal grain solid seed culture to the cooled green coffee beans and culturing them, and separating the cereal grain solid seed culture from the cultured green coffee bean fermented product and then drying it.

Description

[Technical field]

[0001] The present invention relates to a method for producing fermented coffee, the method comprising the steps of applying a cereal grain solid seed culture to sterilized green coffee beans and culturing the same, and separating the cereal grain solid seed culture from the cultured fermented green coffee beans and drying the separated cereal grain solid seed culture, and the fermented coffee produced by the method. [Background technology]

[0002] Coffee belongs to the Rubiaceae family and the genus Coffee. Commercially cultivated varieties are broadly divided into Arabica, Robusta-canephora, and Liberica. Coffee is a representative drink with a balance of bitter, astringent, sour, and sweet tastes, and is the most widely consumed luxury food in the world. In Korea, the coffee market is growing steadily with the proliferation of coffee shops and increased home consumption. Coffee is known to have a high content of antioxidants such as polyphenols compared to other foods, and a high ability to scavenge free radicals that cause cell damage. Recently, it has been reported that roasted coffee beans have a higher content of lipophilic antioxidants and chlorogenic acid, which have a neuroprotective effect, than green coffee beans. Coffee is also known to have excellent protective effects against Alzheimer's disease, Parkinson's disease, type 2 diabetes, cholesterol, heart disease, and cirrhosis of the liver, and there is a trend toward studying the pharmacological effects of coffee beyond its medicinal value.

[0003] Fermented foods are foods made using the fermentation action of microorganisms such as lactic acid bacteria and yeast. There are many different types of fermented foods depending on the type of microorganism and food ingredients. Each type of fermented food has its own unique characteristics and flavor, and the functionality of food ingredients can be improved through fermentation.

[0004] Existing technology involves inoculating sterilized raw coffee beans with mushroom mycelium cultured in a liquid seed culture by liquid injection, which results in high contamination rates due to excessive moisture, which makes the beans unevenly cultured, resulting in low production yields and a black charcoal-like color that reduces the sensory beauty. It also produces a distinctive odor that inhibits the rich and diverse taste and aroma of coffee, significantly reducing productivity and quality competitiveness.

[0005] Korean Patent Publication No. 2021-0101506 discloses a method for producing fermented coffee using yeast that does not require a coffee aging process, and Korean Patent Publication No. 1894295 discloses a method for processing coffee using a fermented plum extract, but these are different from the method for producing fermented coffee cultured with grain solid mushroom mycelium seed culture of the present invention. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Korean Patent Publication No. 2021-0101506 [Patent Document 2] Korean Patent No. 1894295 Summary of the Invention [Problem to be solved by the invention]

[0007] The present invention has been made in response to the above-mentioned demands, and aims to provide a method for producing fermented coffee with excellent useful pharmacological properties and palatability by optimizing pretreatment, sterilization, fermentation, etc. of green coffee beans so as to reduce the bitterness peculiar to coffee and enhance its functionality and flavor. [Means for solving the problem]

[0008] In order to achieve the above object, the present invention provides a method for producing fermented coffee, comprising the steps of: (1) adding Rumex arbutus and Rumex crispus to water, extracting, and then filtering to produce an extract; (2) soaking green coffee beans in the extract produced in step (1); (3) laying ivy leaves in a basket of a sterilizer, placing the soaked green coffee beans of step (2) on the ivy leaves, sterilizing and cooling; (4) applying a cereal grain solid seed culture to the cooled green coffee beans of step (3) and culturing them; and (5) separating the cereal grain solid seed culture from the cultured green coffee bean fermented product of step (4), and then drying it.

[0009] The present invention also provides fermented coffee produced by the above method. Effect of the Invention

[0010] The fermented coffee of the present invention has the advantages of low contamination rate and high production yield by culturing sterilized green coffee beans with cereal grain solid seed culture. It is also possible to provide a high quality fermented coffee by further enriching the flavor and taste of the coffee and improving its functionality. [Brief description of the drawings]

[0011] [Figure 1] This is a photograph of the seed culture separated after culturing green coffee beans with a cereal grain solid seed culture. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] In order to achieve the object of the present invention, the present invention provides (1) adding and extracting Medicago sativa and Rumex japonicus to water, and then filtering the extract to obtain an extract; (2) soaking green coffee beans in the extract produced in step (1); (3) laying vine leaves in a sterilizer basket, placing the soaked green coffee beans from step (2) on the vine leaves, and then sterilizing and cooling the beans; (4) applying a cereal grain solid seed culture to the cooled green coffee beans of step (3) and culturing the same; and (5) A method for producing fermented coffee, comprising the steps of separating a cereal grain solid seed culture from the fermented green coffee beans cultured in step (4) and then drying the separated cereal grain solid seed culture.

[0013] In the method for producing fermented coffee of the present invention, the extract in step (1) can be preferably prepared by adding 4.5-5.5 g of Rumex gracilis and 4.5-5.5 g of Rumex crispus to 180-220 mL of water, extracting at 90-110° C. for 2-4 hours, and filtering the extract. More preferably, the extract can be prepared by adding 5 g of Rumex gracilis and 5 g of Rumex crispus to 200 mL of water, extracting at 100° C. for 3 hours, and filtering the extract.

[0014] Furthermore, in the method for producing fermented coffee of the present invention, the soaking in step (2) is preferably performed by soaking the green coffee beans in the extract at 18 to 22° C. for 5 to 10 hours, and more preferably by soaking the green coffee beans in the extract at 20° C. for 8 hours.

[0015] Furthermore, in the method for producing fermented coffee of the present invention, the sterilization in step (3) can be preferably carried out by laying vine leaves in a sterilizer basket, placing the green coffee beans on the vine leaves, and then sterilizing at 110 to 130°C for 50 to 70 minutes and then cooling, and more preferably by laying vine leaves in a sterilizer basket, placing the green coffee beans on the vine leaves, and then sterilizing at 121°C for 60 minutes and then cooling.

[0016] In order to ferment green coffee beans, the green coffee beans must be soaked and sterilized as described above, as this provides moisture to the green beans, causing them to swell and soften the tissue, which is advantageous in enabling good cultivation.

[0017] Furthermore, in the method for producing fermented coffee of the present invention, step (4) preferably involves applying a cereal grain solid seed culture to cooled green coffee beans and culturing them for 20 to 25 days at 18 to 22° C. Culturing the green coffee beans under the above conditions increases the content of ingredients contained in coffee that are useful to the human body, and improves the taste and aroma of the coffee while reducing the bitterness of the coffee; however, if the culture conditions are outside the above ranges, the culture effect is minimal or an unpleasant odor is generated due to over-fermentation, which is undesirable.

[0018] The solid cereal grain inoculum preferably means that the grain, which has been soaked in water and then sterilized, is inoculated with mushroom mycelium and then cultured.

[0019] The mushroom mycelium may be one or more mushroom mycelium selected from the group consisting of shiitake mushroom, phellinus linteus, Ganoderma lucidum, Poria columbine, Ardisia crenata, Yamabushitake, Cordyceps sinensis, Unshi, Poria columbine, Oyster mushroom, Flammulina velutipes, Pleurotus eryngii, Petal mushroom, Maitake mushroom, Obliquus obliquus, Staghorn beetle mushroom, Auricularia aurantifolia, Staghorn antler Ganoderma lucidum, Matsutake mushroom, Matsutake mushroom, and truffle, but is not limited thereto.

[0020] In addition, the grain may be one or more grains selected from the group consisting of brown rice, white rice, black rice, red rice, green rice, red rice, barley, black barley, oats, wheat, millet, corn, beans, rye, mung beans, pigeon oats, chestnuts, millet, adzuki beans, and buckwheat, but is not limited thereto.

[0021] In the method for producing fermented coffee of the present invention, step (5) preferably involves separating the cereal grain solid seed culture from the cultured fermented green coffee beans and then drying the mixture to a moisture content of 10 to 13% (v / w). Drying under such conditions is preferable in order to prevent additional fermentation of the green coffee beans.

[0022] More specifically, the method for producing fermented coffee of the present invention includes the steps of: (1) adding 4.5-5.5 g of Rumex sieboldii and 4.5-5.5 g of Rumex sieboldii to 180-220 mL of water, extracting at 90-110° C. for 2-4 hours, and then filtering to prepare an extract; (2) soaking green coffee beans in the extract prepared in step (1) at 18-22° C. for 5-10 hours; (3) laying vine leaves in a sterilizer basket, placing the soaked green coffee beans from step (2) on the vine leaves, and then sterilizing at 110-130°C for 50-70 minutes and cooling; (4) applying a cereal grain solid seed culture to the cooled green coffee beans of step (3) and culturing the mixture at 18 to 22° C. for 20 to 25 days; and (5) The method may include a step of separating the cereal grain solid seed culture from the fermented coffee bean culture of the step (4) and drying the solid seed culture to a moisture content of 10 to 13% (v / w); More specifically, (1) adding 5 g of Rumex japonica and 5 g of Rumex candida to 200 mL of water, extracting at 100° C. for 3 hours, and then filtering to prepare an extract; (2) soaking green coffee beans in the extract prepared in step (1) at 20° C. for 8 hours; (3) laying vine leaves in a sterilizer basket, placing the soaked green coffee beans from step (2) on the vine leaves, and then sterilizing at 121°C for 60 minutes and cooling; (4) applying a cereal grain solid seed culture to the cooled green coffee beans of step (3) and culturing the mixture at 18 to 22° C. for 20 to 25 days; and (5) After separating the cereal grain solid seed culture from the fermented green coffee beans cultured in step (4), the method may include a step of drying the solid seed culture to a moisture content of 10 to 13% (v / w). The present invention also provides fermented coffee produced by the above method. The present invention will be described in detail below with reference to examples. However, the following examples are merely illustrative of the present invention, and the content of the present invention is not limited to the following examples.

[0023] Production Example 1. Fermented coffee (1) 5 g of Rumex officinalis and 5 g of Rumex japonicus were added to 200 mL of purified water, and the mixture was extracted at 100° C. for 3 hours and then filtered to prepare an extract. (2) 100 g of green coffee beans were soaked in 200 mL of the extract prepared in step (1) at 20° C. for 8 hours. (3) Ivy leaves were laid in a sterilizer basket, and the soaked green coffee beans from step (2) were placed on top of the vine leaves. The beans were then sterilized at 121°C for 60 minutes and cooled to 20°C in a cooling room. (4) 15 mL of brown rice grain solid seed culture was evenly applied to the top of the cooled green coffee beans from step (3) and cultured in a culture room at 18-22°C for 20-25 days. After 10 days of inoculation during the culture, the container was shaken to create gaps so that the lower part of the container and the entire container could be cultured evenly. The brown rice grain solid seed culture refers to brown rice soaked in water, sterilized, and then inoculated with shiitake mushroom mycelium, followed by culture at 25°C for 20 days. (5) After separating the brown rice grain solid seed culture from the fermented green coffee beans cultured in step (4), the fermented green coffee beans were dried to a moisture content of 10 to 13% (v / w).

[0024] Comparative Example 1: Coffee (1) 100 g of raw coffee beans were soaked in 200 mL of purified water at 20° C. for 8 hours. (2) The soaked green coffee beans from step (1) were placed in a sterilizer basket and then sterilized at 121°C for 60 minutes and cooled to 20°C in a cooling room. (3) The cooled green coffee beans from step (2) were dried to a moisture content of 10 to 13% (v / w).

[0025] Comparative Example 2: Fermented Coffee (1) 100 g of raw coffee beans were soaked in 200 mL of purified water at 20° C. for 8 hours. (2) The soaked green coffee beans from step (1) were placed in a sterilizer basket and then sterilized at 121°C for 60 minutes and cooled to 20°C in a cooling room. (3) 15 mL of the brown rice grain solid seed culture was evenly spread on the top of the cooled green coffee beans from step (2) and cultured in a culture room at 18-22°C for 20-25 days. After 10 days of inoculation during the culture, the container was shaken to create spaces so that the bottom of the container and the entire container could be cultured evenly. The brown rice grain solid inoculum refers to brown rice soaked in water, sterilized, inoculated with Lentinus edodes mycelium, and then cultured at 25° C. for 20 days. (4) After separating the brown rice grain solid seed culture from the fermented green coffee beans cultured in step (3), the fermented green coffee beans were dried to a moisture content of 10 to 13% (v / w).

[0026] Comparative Example 3: Fermented Coffee (1) 10 g of Panax notoginseng was added to 200 mL of purified water, and the mixture was extracted at 100° C. for 3 hours and then filtered to prepare an extract. (2) Using the extract prepared in step (1), fermented coffee was prepared in the same manner as steps (2) to (5) of Preparation Example 1.

[0027] Comparative Example 4. Fermented Coffee (1) 10 g of R. nipponica was added to 200 mL of purified water, and extracted at 100° C. for 3 hours, followed by filtration to prepare an extract. (2) Using the extract prepared in step (1), fermented coffee was prepared in the same manner as steps (2) to (5) of Preparation Example 1.

[0028] Comparative Example 5. Fermented Coffee (1) 5 g of Rumex officinalis and 5 g of Rumex japonicus were added to 200 mL of purified water, and the mixture was extracted at 100° C. for 3 hours and then filtered to prepare an extract. (2) 100 g of green coffee beans were soaked in 200 mL of the extract prepared in step (1) at 20° C. for 8 hours. (3) The soaked green coffee beans from step (2) were placed in a sterilizer basket and then sterilized at 121°C for 60 minutes and cooled to 20°C in a cooling room. (4) The cooled green coffee beans from step (3) were used to produce fermented coffee in the same manner as steps (4) and (5) of Production Example 1. EXAMPLES

[0029] Example 1. Beta-glucan analysis Beta-glucan in the samples was measured using a Megazyme kit (Mushroom and Yeast β-glucan Assay Procedure K-YBGL, Megazyme, Ireland).

[0030] First, total glucan was decomposed by placing 100 mg of ground sample sieved through a 100 mesh sieve in a tube, adding 1.5 mL of 37% HCl, and placing in a thermostatic water bath at 30°C for 45 minutes. Then, 10 mL of distilled water was added, vortexed, and incubated at 100°C for 2 hours. After that, while cooling at room temperature, 10 mL of 2N KOH was added, and the volume was adjusted to 100 mL with 200 mM sodium acetate buffer, and then thoroughly mixed. Then, 0.1 mL of exo-1, 3-β-glucanase plus β-glucosidase dissolved in 200 mM sodium acetate buffer was added to 0.1 mL of the supernatant, 0.2 mL of acetate buffer was added to the reagent blank, and 0.1 mL of D-glucose standard and 0.1 mL of acetate buffer were added to the D-glucose standard, mixed, and incubated at 40°C for 60 minutes. Next, 3 mL of GOPOD (glucose oxidase / peroxidase mixture) was added and incubated at 40°C for 20 minutes, and the absorbance was measured at 510 nm.

[0031] For α-glucan, 100 mg of ground sample sieved through a 100 mesh sieve was placed in a tube and mixed with 2 mL of 2M KOH for 20 minutes. After mixing with 8 mL of 1.2M sodium acetate buffer, 0.2 mL of amyloglucosidase plus invertase was added, mixed well, and incubated in a 40°C thermostatic water bath for 30 minutes. 0.1 mL of the supernatant was added with 0.1 mL of 200 mM sodium acetate buffer and 3 mL of GOPOD, incubated at 40°C for 20 minutes, and then measured at 510 nm absorbance. The calculation was based on the total glucan content, and the α-glucan content was subtracted to quantify the β-glucan content.

[0032] [Table 1]

[0033] As a result, no β-glucan was detected in the coffee of Comparative Example 1, and the fermented coffee of Production Example 1 had a higher β-glucan content than the fermented coffee of Comparative Example 2.

[0034] Example 2. DPPH radical scavenging ability To investigate the antioxidant capacity of each coffee, antioxidant activity was measured by hydrogen electron donating capacity. The samples were diluted with distilled water, and 10 μL of each sample was mixed with 900 μL of DPPH solution (100 μM) and stirred. The mixed samples were reacted in the dark for 30 minutes, and then the absorbance was measured at 517 nm. The hydrogen electron donating capacity was calculated by averaging each experiment three times, and the degree of decrease in absorbance compared to the control was calculated using the following formula.

[0035] DPPH radical scavenging ability (%) = (AB) / A x 100 A: Absorbance of DPPH solution without sample added B: Absorbance of the reaction between DPPH and the sample in the reaction solution

[0036] [Table 2]

[0037] The fermented coffee was diluted and the DPPH radical scavenging ability was measured, and the results are shown in Table 2. As a result, it was found that the fermented coffee of Production Example 1 had the highest DPPH radical scavenging ability.

[0038] Example 3. Sensory test A sensory test was conducted on the coffees of Production Example 1 and Comparative Example by 50 sensory testers. Each coffee was roasted to medium roast, crushed, and hand-dripped with hot water to obtain a coffee extract. The aroma, taste, softness, and overall preference were classified into 1: very bad, 2: bad, 3: average, 4: good, and 5: very good, and the average was calculated and shown.

[0039] [Table 3]

[0040] The results of the sensory test of the extracts extracted from each coffee are shown in Table 3. As a result, the fermented coffee of Preparation Example 1 showed higher scores in all items than the coffees of the Comparative Examples, and it was found that the fermented coffee of Preparation Example 1 has a high β-glucan content, excellent antioxidant activity, and is suitable for consumer preferences.

Claims

1. (1) adding 4.5-5.5 g of Rumex officinalis and 4.5-5.5 g of Rumex crispus to 180-220 mL of water, extracting at 90-110°C for 2-4 hours, and then filtering to prepare an extract; (2) soaking green coffee beans in the extract prepared in step (1) at 18-22°C for 5-10 hours; (3) placing ivy leaves in a basket of a sterilizer, placing the soaked green coffee beans from step (2) on the ivy leaves, and then sterilizing the beans at 110-130°C for 50-70 minutes, followed by cooling; (4) applying a cereal grain solid inoculum to the cooled green coffee beans of step (3) and culturing the mixture at 18 to 22°C for 20 to 25 days; and (5) A method for producing fermented coffee, comprising the steps of separating a cereal grain solid seed culture from the fermented green coffee beans cultured in step (4) and then drying the solid seed culture to a moisture content of 10 to 13% (v / w).

2. 2. The method for producing fermented coffee according to claim 1, wherein the grain is one or more grains selected from the group consisting of brown rice, white rice, black rice, red rice, green rice, red rice, barley, black barley, oats, wheat, sorghum, corn, beans, rye, mung beans, pigeon oats, chestnuts, millet, adzuki beans, and buckwheat.

Images