Method for manufacturing zero-alcohol makgeolli using rice nuruk

Abstract

The present disclosure relates to a method for producing alcohol-free makgeolli using rice koji. According to one embodiment, the method may include the steps of: preparing steamed rice by washing and steaming main raw grains and mixing them with rice koji; inoculating the steamed rice with a strain treated to inhibit alcohol production and lactic acid bacteria; obtaining a first fermentation liquid by performing a first fermentation of the fermentation base material inoculated with the strain and lactic acid bacteria in an environment with a preset temperature and pH condition; obtaining a second fermentation liquid by adding natural fermentation microorganisms to the first fermentation liquid to reduce the alcohol content and proceeding with a second fermentation; and aging the second fermentation liquid.

Description

Technology Field

[0001] The present disclosure relates to a method for producing alcohol-free makgeolli. More specifically, it relates to a method for stably producing alcohol-free makgeolli with an alcohol content of 0.0% by preparing steamed rice with rice koji to effectively suppress alcohol production while maintaining the flavor and nutrition of traditional makgeolli. Background Technology

[0002] Makgeolli is a unique traditional Korean alcoholic beverage produced by fermenting grains, but it is characterized by an alcohol content generally ranging from 5 to 8 percent. Recently, with the spread of health-oriented consumption and trends favoring vegan and non-alcoholic beverages, there is an increasing demand for makgeolli with reduced or no alcohol content.

[0003] Previously, techniques have been attempted to reduce alcohol content using physical methods such as distillation or vacuum distillation, or to reduce ethanol production by controlling fermentation temperature. However, these methods make it difficult to maintain the unique taste and aroma of makgeolli, and in many cases, they only managed to lower the alcohol content to 0.2% or less. Additionally, there are technical requirements to preserve the flavor components and beneficial bacteria (such as lactic acid bacteria) produced during the fermentation process.

[0004] In particular, the fermentation mechanism in which yeast breaks down sugar to produce ethanol plays a crucial role in the traditional makgeolli production process in terms of taste, aroma, and nutrition. However, to produce makgeolli with an alcohol content of 0.0%, it is necessary to fundamentally control the alcohol production pathway while maintaining the activity of fermentation microorganisms, or to undergo a separate alcohol removal process after fermentation. During this process, the fermented flavor may be lost, lactic acid bacteria may die, and problems with product shelf life may arise.

[0005] Meanwhile, the domestic and international fermented food market continues to grow, and as the number of health-conscious consumers increases, non-alcoholic makgeolli is emerging as a new opportunity in the premium beverage market. However, due to the unique technical difficulties and yield issues inherent in non-alcoholic makgeolli, as well as the challenge of maintaining the flavor of traditional liquor, there are not many commercially available products yet. Therefore, there is a demand for a manufacturing method that maintains an alcohol content of exactly 0.0% while simultaneously satisfying the flavor of traditional makgeolli and a high lactic acid bacteria content.

[0006] Accordingly, the present invention requires the development of a technology capable of stably producing alcohol-free makgeolli that contains substantially no alcohol by selectively inhibiting the alcohol production pathway during the fermentation process and optimizing the types of fermentation microorganisms and fermentation conditions.

[0007] Furthermore, there is a need for a makgeolli manufacturing technology that compensates for the disadvantages of existing vacuum distillation or physical removal methods while preserving functional components such as lactic acid bacteria. In particular, a key feature of this invention is a method of producing steamed rice using rice koji (oat koji can also be used) and preserving the authentic flavor of makgeolli regardless of the degree of fermentation.

[0008] Therefore, a method for producing makgeolli and a technology for producing the same are required, which can enhance the flavor of makgeolli regardless of the degree of fermentation by utilizing rice koji. The problem to be solved

[0009] According to one embodiment, a method for manufacturing makgeolli can be provided.

[0010] According to one embodiment, a method for producing alcohol-free makgeolli using rice koji can be provided. means of solving the problem

[0011] As a technical means for achieving the technical problem described above, according to one embodiment, a method for manufacturing alcohol-free makgeolli may be provided, comprising: a step of preparing a fermentation base material by washing and steaming the main raw grains; a step of inoculating the fermentation base material with a strain treated to inhibit alcohol production and lactic acid bacteria; a step of obtaining a first fermentation liquid by performing a first fermentation of the fermentation base material inoculated with the strain and lactic acid bacteria in an environment with preset temperature and pH conditions; a step of obtaining a second fermentation liquid by adding natural fermentation microorganisms to the first fermentation liquid to reduce the alcohol content and proceeding with a second fermentation; and a step of aging the second fermentation liquid. Effects of the invention

[0012] According to one embodiment, makgeolli can be produced by making steamed rice with rice koji or oat koji, and by suppressing the alcohol production pathway during the fermentation process and lowering the alcohol content through secondary fermentation, it is possible to provide makgeolli that contains virtually no alcohol (at the 0.0% level).

[0013] According to one embodiment, by appropriately combining fermentation microorganisms (yeast, lactic acid bacteria, etc.) and optimizing fermentation conditions, the unique taste and aroma of traditional makgeolli can be maintained, and in particular, steamed rice made using rice nuruk can increase fermentation efficiency while suppressing alcohol. Brief explanation of the drawing

[0014] FIG. 1 is a flowchart of a method for manufacturing alcohol-free makgeolli according to one embodiment. FIG. 2 is a flowchart specifically illustrating a secondary fermentation process according to one embodiment. Figure 3 is a flowchart of a method for manufacturing alcohol-free makgeolli according to another embodiment. Specific details for implementing the invention

[0015] In order to provide a detailed explanation sufficient for a person skilled in the art to easily implement the technical concept of the present invention, embodiments of the present invention will be described with reference to the accompanying drawings. However, the following embodiments are merely examples to aid in understanding the present invention and do not reduce or limit the scope of the rights of the present invention. Furthermore, the present invention may be implemented in various different forms and is not limited to the embodiments described herein.

[0017] FIG. 1 is a flowchart of a method for manufacturing alcohol-free makgeolli according to one embodiment.

[0018] In the S100, a fermentation base material can be prepared by washing and steaming the main grain ingredients. Ingredients used in the production of traditional Makgeolli, such as rice, wheat, and barley, can be used as the grains; during the washing process, foreign substances and micro-contaminants are removed, and through steaming, the starch structure is transformed into a state suitable for fermentation. While these steaming conditions are similar to existing Makgeolli production methods, it is important to manage the appropriate moisture content and steaming temperature within a certain range to suppress alcohol production.

[0019] In particular, the present invention is characterized by preparing rice koji (or oat koji) in advance and mixing it with steamed rice to form cooked rice. Cooked rice made with rice koji has higher fermentation characteristics than ordinary koji, allowing for the maximization of flavor while minimizing alcohol production.

[0020] For example, in step S100 above, 500g of rice can be washed thoroughly 2 to 3 times and then steamed at about 100°C for 20 minutes to prepare a fermentation base. At this time, by steaming with a ratio of rice to water of 1:1.2, a fermentation base that facilitates starchization and has high fermentation efficiency can be obtained.

[0021] In the S200, strains treated to inhibit alcohol production and lactic acid bacteria can be inoculated into the fermentation base. This can be seen as a key step in fundamentally reducing the alcohol fermentation pathway while preserving the authentic flavor of Makgeolli. The strains used here can be selected based on the alcohol-free Makgeolli manufacturing technologies mentioned in existing reference patents, or mixed strains selected through internal corporate research can be applied. These strains are specialized to maintain taste and aroma while minimizing ethanol production, while the lactic acid bacteria simultaneously play a supporting role in enhancing the functionality of the fermented food.

[0022] For example, by adding a strain (a mixture of yeast and lactic acid bacteria) at a ratio of 0.5 to 1.0% relative to the base material for fermentation and activating it in an environment of around 25°C, it is possible to simultaneously inhibit alcohol production and form a fermented flavor.

[0023] In S300, a primary fermentation liquid can be obtained by primary fermenting a base mixture containing the strain inoculated in S200 and lactic acid bacteria under preset temperature and pH conditions. At this time, the fermentation temperature is controlled to maintain a range of approximately 20 to 25 degrees so that alcohol-inhibiting yeast can proliferate stably, and it is also desirable to manage the pH between approximately 4.0 and 4.5. Under these conditions, the strain and lactic acid bacteria proceed with the fermentation process to form the characteristic flavor components of makgeolli while maintaining a low ethanol concentration.

[0024] The reason why steamed rice using rice koji is important in this invention is that the steamed rice itself contains abundant beneficial enzymes and fermentation factors, so alcohol production is significantly suppressed despite the excellent fermentation speed and flavor formation.

[0025] In S400, to further reduce the alcohol content, natural fermentation microorganisms are added to the primary fermentation liquid, and a secondary fermentation liquid is obtained by proceeding with secondary fermentation. During secondary fermentation, the oxygen supply is restricted to below a standard threshold as needed, and lactic acid bacteria proliferation is induced by adding carbohydrates or minerals. By doing so, alcohol production is further suppressed, and ultimately, a level of lactic acid bacteria of 1 billion or more per mL can be stably maintained. Unlike the method of physically removing alcohol (such as vacuum distillation) when manufacturing alcohol-free makgeolli as described in Reference Patents 1, 2, and 3, this method, which suppresses ethanol production by controlling the fermentation process itself, has the advantage of being able to reduce alcohol to practically 0.0% while maintaining the unique flavor generation pathways of the fermentation microorganisms as much as possible.

[0026] In addition, by adjusting the sugar content of the primary fermentation liquid to a level of 10 to 12 Brix and adding 0.2% to 0.3% of natural fermentation microorganisms before starting the secondary fermentation, a rich fermented aroma and a high number of lactic acid bacteria can be obtained without alcohol production.

[0027] In the S500, the obtained secondary fermented liquid can be aged. During the aging stage, the secondary fermented liquid is left for a certain period at a temperature range of approximately 10 to 15 degrees Celsius to remove off-flavors that may be generated during the initial fermentation process and to stabilize the smooth texture and flavor characteristic of Makgeolli. Fermentation byproducts or fine particles generated during this process naturally settle or separate from the supernatant over time, making them easy to remove during the subsequent filtering process. Furthermore, lactic acid bacteria remain active even in an environment with almost no alcohol during the aging period, which can further enhance the functionality of the alcohol-free Makgeolli (such as improving gut health and forming beneficial bacterial flora).

[0028] Thus, through the method for manufacturing alcohol-free makgeolli according to one embodiment, it is possible to implement a process flow that effectively suppresses alcohol production while securing the flavor of traditional makgeolli and a high lactic acid bacteria content.

[0029] Thus, through the method for manufacturing alcohol-free makgeolli according to one embodiment, a process flow can be implemented in which steamed rice is made using rice koji or oat koji, and then alcohol production is effectively suppressed while securing the flavor of traditional makgeolli and a high lactic acid bacteria content.

[0031] FIG. 2 is a flowchart specifically illustrating a secondary fermentation process according to one embodiment.

[0032] First, in the S210 stage, additional natural fermentation microorganisms may be introduced into the fermentation tank so that the lactic acid bacteria content reaches 1 billion CFU / mL or more at the end of the second fermentation. This is a key measure to ensure that beneficial bacteria, including lactic acid bacteria, can be sufficiently activated even during the intensifying process of fermentation, based on the fact that alcohol-inhibiting strains and lactic acid bacteria have already proliferated to a certain amount during the first fermentation. In particular, since maximizing the lactic acid bacteria content is important for enhancing the flavor and nutritional value of non-alcoholic makgeolli during the second fermentation, the additional introduction of natural fermentation microorganisms becomes a major factor in determining fermentation efficiency and final quality.

[0033] For example, if 0.1% of mixed strains are additionally inoculated at the start of the second fermentation and the initial pH is set to about 4.3, the lactic acid bacteria will continuously increase until the later stages of fermentation, and a high concentration of lactic acid bacteria content of more than 1 billion / mL can be achieved.

[0034] In the S220 stage, the oxygen supply within the fermentation tank where secondary fermentation takes place can be reduced to below a preset threshold to allow the previously introduced natural fermentation microorganisms to effectively colonize and proliferate. Generally, excessive oxygen supply during the makgeolli fermentation process can lead to the proliferation of unwanted bacteria or a decrease in the survival of lactic acid bacteria; therefore, it is necessary to optimize fermentation conditions by stabilizing the oxygen concentration within the tank. At this time, limiting the oxygen supply to a certain level also inhibits the ethanol production pathway, which helps create an alcohol-free environment. Furthermore, since lactic acid bacteria are characterized by accelerated proliferation in relatively low-oxygen conditions, maintaining oxygen conditions below the threshold allows the number of lactic acid bacteria to increase rapidly even during the intermediate stages of fermentation.

[0035] As an example, if the oxygen concentration inside the fermentation tank is managed to 2 ppm or less (a value significantly lower than that of general fermentation), the alcohol production rate is rapidly suppressed, and the lactic acid bacteria activity is actually increased.

[0036] In the S230 stage, when the oxygen supply is reduced below the standard threshold, additional carbohydrates and minerals can be introduced into the fermentation tank. This serves to replenish nutrients consumed during secondary fermentation and helps microorganisms sustain fermentation stably. Carbohydrates are used by fermentation microorganisms as an energy source, contributing to their proliferation and fermentation activity, while minerals are essential elements that aid microbial metabolism, thereby increasing the survival rate and fermentation efficiency of lactic acid bacteria. Through this combination, fermentation microorganisms, including lactic acid bacteria, secure a sufficient growth environment until the very end of secondary fermentation; consequently, a secondary fermentation liquid with significantly increased lactic acid bacteria content and almost no alcohol content can be obtained.

[0037] Specifically, when about 35% of carbohydrates are added and 0.1% of a mineral complex including calcium and magnesium is added, the number of lactic acid bacteria can rise to 1.2 to 1.5 billion / mL at the end of the second fermentation.

[0038] In this way, during the secondary fermentation process (S210~S230), the additional input of natural fermentation microorganisms, restriction of oxygen supply, and supplementation of carbohydrates and minerals are organically combined to maximize the lactic acid bacteria content in the alcohol-free makgeolli. Furthermore, by strictly controlling the fermentation conditions, it is effective in suppressing the rise in alcohol concentration and maintaining the fermented flavor. Ultimately, this secondary fermentation process provides essential technical features for manufacturing alcohol-free makgeolli that preserves the taste and aroma of traditional makgeolli while maintaining an alcohol content close to 0.0%. According to one embodiment, oat koji can be partially mixed and used in the secondary fermentation process of FIG. 2, which induces diversification of fermented flavors and contributes to alcohol suppression.

[0040] Figure 3 is a flowchart of a method for manufacturing alcohol-free makgeolli according to another embodiment.

[0041] Since the filtering and inspection process described in Fig. 3 is also a fermented liquid based on steamed rice koji, it has the advantage of producing fewer unwanted bacteria and fine sediment compared to regular makgeolli, and can maintain an alcohol content close to 0.0% during the final inspection.

[0042] According to one embodiment, in step S310, the secondary fermented liquid, which has been left for a preset maintenance period, can be filtered using a sterile filter. After sufficient fermentation and maturation are achieved, the hygienic condition and stability of the product are ensured by using a sterile filter to remove fine particles, contaminants, and abnormal fermentation byproducts that may remain in the fermented liquid. By carefully controlling the type of filter used, the pressure of the filtering process, and the flow rate during this process, it is possible to exclude only unnecessary suspended solids while maintaining sufficient lactic acid bacteria, thereby maximizing the clean appearance and smooth texture of the alcohol-free makgeolli. For example, if filtration is performed at a low pressure of about 0.5 bar or less using a sterile filter with a pore size of 1 μm (micrometer), the loss of lactic acid bacteria can be minimized while simultaneously enhancing the effect of improving turbidity.

[0043] Subsequently, in step S320, an inspection process can be performed on the filtered secondary fermented liquid, including checking the status of additives, alcohol content, acidity, and measuring lactic acid bacteria activity. Through this, it is determined whether the non-alcoholic makgeolli as a final product meets the standards for distribution and sale. First, checking the status of additives is a procedure to inspect whether unnecessary additives, such as synthetic sweeteners or synthetic preservatives, have been included, in order to comply with the principles of 'natural fermentation' and 'no additives' emphasized in this invention. Checking the alcohol content is a process of re-verifying whether the result of thoroughly suppressing alcohol production in the preceding steps is actually at the 0.0% level (or below the legal limit), and is a key factor in guaranteeing that it is an alcohol-free product. Checking the acidity is performed to confirm whether the taste of the makgeolli and lactic acid bacteria fermentation have proceeded properly and whether the acidity range is optimized; finally, measuring lactic acid bacteria activity serves as a key indicator to determine whether it meets or exceeds the minimum standards required for a fermented beverage in order to maintain the functionality and quality of the product.

[0044] For example, during the final product inspection, if the acidity is around pH 4.2, the alcohol concentration is in the range of 0.0–0.1%, and the lactic acid bacteria activity is 90% or higher, it can be considered to have passed the product shipment standards. Through this inspection process, it can be confirmed once again that the final produced alcohol-free makgeolli possesses taste, aroma, and abundant lactic acid bacteria while suppressing alcohol fermentation. Consequently, the flowchart 3 specifically illustrates an important step that enables the stable mass production and commercialization of alcohol-free makgeolli by undergoing filtering and quality verification processes in addition to the existing fermentation process.

[0045] Although embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements by those skilled in the art using the basic concept of the present invention as defined in the following claims also fall within the scope of the present invention.

Claims

Claim 1 A method for manufacturing alcohol-free makgeolli using rice koji, comprising: a step of preparing steamed rice by washing and steaming the main raw grain and mixing it with rice koji; a step of inoculating the steamed rice with a strain treated to inhibit alcohol production and lactic acid bacteria using the steamed rice as a fermentation base; a step of obtaining a first fermentation liquid by performing a first fermentation of the steamed rice-based fermentation base inoculated with the strain and lactic acid bacteria under a preset temperature and pH condition; a step of obtaining a second fermentation liquid by adding natural fermentation microorganisms to the first fermentation liquid to reduce the alcohol content and proceeding with a second fermentation; and a step of aging the second fermentation liquid. Claim 2 A method for producing alcohol-free makgeolli according to claim 1, wherein the strain treated to inhibit alcohol production comprises a mixed strain of yeast and lactic acid bacteria selected to minimize ethanol production during the fermentation process while maintaining taste and aroma. Claim 3 A method for manufacturing alcohol-free makgeolli according to claim 2, wherein the step of obtaining the secondary fermentation liquid comprises: a step of adding natural fermentation microorganisms during the secondary fermentation so that the lactic acid bacteria content is 1 billion / mL or more at the end of the secondary fermentation; a step of reducing the oxygen supply amount in the fermentation tank where the secondary fermentation in which the natural fermentation microorganisms were added is carried out to below a preset threshold after adding the natural fermentation microorganisms; and a step of adding sugars and minerals in the fermentation tank while the oxygen supply amount is reduced to below the threshold. Claim 4 In claim 3, the method for manufacturing non-alcoholic makgeolli further comprises the step of leaving the aged secondary fermented liquid at a temperature range of 10 to 15 degrees for a preset maintenance period to remove off-flavors that may be generated in the secondary fermented liquid during the secondary fermentation process, and to improve flavor and viscosity. Claim 5 In claim 4, the method for manufacturing alcohol-free makgeolli comprises: a step of filtering a secondary fermented liquid that has been left for a preset maintenance period using a sterile filter; and a step of performing an inspection process on the filtered secondary fermented liquid, including checking the additive status, checking the alcohol content, checking the acidity status, and measuring the lactic acid bacteria activity.

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