Method for producing malt

Abstract

The application discloses a malt manufacturing method, which comprises at least one malting step, and in the at least one malting step, the grains are immersed in hydrogen water with a dissolved hydrogen concentration of 0.3-1.6 ppm. By using hydrogen-rich water in malt manufacturing, the application can improve multiple quality indicators at the same time. The positive biological effect of hydrogen-rich water is particularly significant. The increase of the alpha-amino nitrogen content of the malt brings higher economic benefits to the malt manufacturer. Moreover, the color and turbidity of the malt are significantly reduced, effectively solving the problem that wort is easy to be turbid.

Description

TECHNICAL FIELD

[0001] The present invention relates to a malt manufacturing process. More particularly, it relates to a process for using hydrogen-rich water in malt manufacturing, and the malt and fermented beverage obtained by the process. BACKGROUND

[0002] Grains of cereals can be used in beverages and foodstuffs as such or as malted grains. Malt is more suitable as a fermentation substrate due to its high enzyme content, as well as for adding malt flavour and nutrients in foodstuffs and beverages.

[0003] About 96% of the total malt produced worldwide is used in the production of alcoholic beverages, about 3% is used in the distilling industry, and the rest is used in the food industry, such as malt beverages. Malt suitable for alcoholic beverage production contains active amylase and protease enzymes. Malting of barley enables the enzymes to cause a moderate solubilization of starch and protein and the formation of precursors for brewing. The malt process has become an independent industry. Maltsters purchase cereals, such as barley, sorghum, wheat and rye, and process them through various procedures to produce different types of malt suitable for brewing.

[0004] Taking barley as an example, it is processed into malt through steps of pre-treatment, steeping, germination, green malt kilning and drying, and rootlet removal. After mashing, wort is produced. Worts are the main source of sugar for yeast metabolism in the brewing of alcoholic beverages. The final products, alcohol and carbon dioxide, impart the special foam and cooling sensation to beer, and also bring the flavour of malt to the taste. The amylase and protease enzymes in malt work together to convert non-fermentable polysaccharides into fermentable sugars, while the content of alpha-amino nitrogen, the content of foam-protein and the distribution of protein are also changed accordingly.

[0005] The steps that are particularly important in traditional malt manufacturing include steeping, germination and kilning. The steeping process means that the grains are soaked in water for several hours, then air rested for a period of time to remove the water. This air rest stage is considered necessary because the submerged grains can become oxygen deficient. The steeping and air rest stages can be repeated several times. The grains are then transferred to a germination device. The goal of germination is to continue to produce enzymes inside the grains that are able to break down the rigid structure of the grain, making it more useful for food and beverage processing. Small rootlets are formed during germination. The water content can be adjusted by adjusting the steeping process based on the barley variety and the type of malt to be produced.

[0006] The composition and quality of malt directly affect the flavor and quality of fermented beverages. Key quality indicators of malt include α-amino nitrogen, color, and turbidity. Besides the influence of barley variety and quality (such as protein content and grain size), malting is a crucial step affecting these quality indicators.

[0007] Currently, malting and soaking equipment is relatively mature, and the quality of barley raw materials is stable. Therefore, people often focus on improving one or more quality indicators in hopes of producing high-quality malt. However, when improving a particular quality indicator, it is often impossible to consider the impact on other quality indicators. For example, existing technologies have reported that adding riboflavin (Rong Zhiming, Research on Improving Malt Quality Using Exogenous Substances [D]. Dalian University of Technology, 2016) increased malt extract by 0.6% and α-amino nitrogen by 27 mg / 100g. However, the addition of riboflavin also increased the malt color by nearly 1.5 EBC, which is a highly undesirable adverse effect on wort and beer quality for malt producers. There are also reports that adding mannitol increased malt extract by 1.1% and α-amino nitrogen by 22 mg / 100g. However, the addition of mannitol also increased the malt color by nearly 0.4 EBC, which is also undesirable.

[0008] Hydrogen is a biosafe gaseous signaling molecule. Chinese invention patent CN102657221B discloses a hydrogen-rich liquid plant growth regulator, wherein the hydrogen saturation is 0.1% to 100%, and the solvent is Hoagland nutrient solution, Kimura B nutrient solution, TAP nutrient solution, or MS culture medium. This regulator gradually releases hydrogen, promoting plant growth, development, and morphogenesis, and increasing yield. Another document (The Tale of a Neglected Energy Source: Elevated Hydrogen Exposure Affects both Microbial Diversity and Function in Soil, Mondher Khdhiri et, Applied and Environmental Microbiology, June 2017, Volume 83.) discloses that the enrichment of hydrogen produced by nitrogen fixation on hydrogen-oxidizing bacteria has been shown to have a fertilizing effect on various crops. When hydrogen is supplied to the soil, it alters the ecological niche division of bacteria and fungi, having multifaceted effects on microbial functional diversity. Summary of the Invention

[0009] The purpose of the present application is to improve the malt quality desired by maltsters and the brewing industry, while improving color, turbidity, and alpha-amino nitrogen content. No adverse effects on other quality indicators are caused by the improvement of a certain quality indicator. The biological effects of hydrogen are further exploited, and it is safe and reliable. No additional additives are introduced in the malt manufacturing process.

[0010] To achieve the above-mentioned purpose of the present application, the first aspect of the present application discloses a malt manufacturing method, which performs at least one steeping step on the grains, and in at least one steeping step, the grains are immersed in hydrogen water with a dissolved hydrogen concentration of 0.3 to 1.6 ppm.

[0011] Further, in at least one steeping step, the grains are immersed in hydrogen water with a dissolved hydrogen concentration of 0.3 to 1.2 ppm, preferably 0.6 to 1.2 ppm.

[0012] Further, after the steeping step, the grains start to germinate, and at least once, hydrogen water with a dissolved hydrogen concentration of 0.3 to 1.6 ppm is used to keep the surface of the grains wet.

[0013] Further, after the steeping step, the grains start to germinate, and at least once, hydrogen water with a dissolved hydrogen concentration of 0.3 to 1.2 ppm, preferably 0.6 to 1.2 ppm, is used to keep the surface wet.

[0014] Further, the temperature of at least one steeping is in the range of 10°C to 20°C, preferably in the range of 14°C to 18°C.

[0015] Further, the number of steeping is twice, and both the first steeping and the second steeping immerse the grains in hydrogen water with a dissolved hydrogen concentration of 0.3 to 1.6 ppm.

[0016] Further, the time of at least one steeping lasts for more than 3 hours, preferably more than 4 hours, and more preferably more than 5 hours.

[0017] Further, the temperature of germination is in the range of 12 to 25°C, preferably in the range of 14 to 20°C, more preferably in the range of 14 to 18°C, and most preferably in the range of 16 to 18°C.

[0018] Further, at least once, hydrogen water is used every 20 to 25 hours from the start of germination.

[0019] The second aspect of the present application provides the use of the malt manufacturing method according to the first aspect to reduce the color of malt.

[0020] The third aspect of the present application provides the use of the malt manufacturing method according to the first aspect to reduce the turbidity of malt.

[0021] The fourth aspect of the present application provides a use of the malt manufacturing method according to the first aspect to increase the content of alpha-amino nitrogen in malt.

[0022] The fifth aspect of the present application provides malt obtained by the malt manufacturing method according to the first aspect.

[0023] The sixth aspect of the present application provides a use of the malt according to the fifth aspect in the preparation of a fermented beverage.

[0024] Further, the fermented beverage includes beer, beer-flavored beverage or whiskey.

[0025] Compared with the prior art, the technical solution provided by the present application has the following advantages:

[0026] 1. The present application can improve multiple quality indicators at the same time by using hydrogen-rich water in malt manufacturing. The positive biological effects of hydrogen-rich water are particularly significant. The increase in the content of alpha-amino nitrogen in malt brings higher economic benefits to malt manufacturers. In addition, the color and turbidity of malt are significantly reduced, effectively solving the problem of wort turbidity.

[0027] 2. The present application also provides the use stage and appropriate concentration range of hydrogen-rich water, which is an important guide for malt manufacturers.

[0028] 3. The introduction of hydrogen-rich water into malt manufacturing does not involve the introduction of exogenous compounds and exogenous enzyme preparations compared with the prior art, and has high biological safety. DETAILED DESCRIPTION

[0029] The specific embodiments of the present application are described in detail below. However, the present application should be understood as not being limited to this embodiment described below, and the technical concept of the present application can be implemented in combination with other known technologies or other technologies having the same functions as those known technologies.

[0030] In addition, the terms "first", "second", etc. are used only for descriptive purposes and are not to be taken literally or to imply a relative importance or a specific order of importance of the features so described, and are merely used to distinguish one feature from another. Thus, a feature described as a "first" feature can imply or be understood to implicitly include one or more of the features. In the description of the present application, the meaning of "a plurality" is two or more, unless explicitly specified otherwise. Similarly, the use of the indefinite article "a" or "an" herein is not intended to be limiting, but rather, is used to describe a preceding feature. Similarly, unless a specific quantity of a feature is modified by a specific quantity term, it is to be understood that both the singular and plural forms are included in the description herein. Similarly, the use of modifiers such as "approximately", "about", etc. before a numeral herein generally includes the numeral and its specific meaning, and the specific meaning is to be understood in light of the context of the description.

[0031] It should be understood that in the present application, "at least one" means one or more, and "multiple" means two or more. "And / or" is used to describe the relationship between the associated objects, which means that there can be three relationships, for example, "A and / or B" can mean that there are three cases: only A, only B, and A and B at the same time, where A and B can be singular or plural. The character " / " generally represents an "or" relationship between the associated objects. "At least one of the following" or the like means any combination of these items, including any combination of single or multiple items. For example, at least one of a, b or c can mean a, b, c, "a and b", "a and c", "b and c", or "a and b and c", where a, b, and c can be single or multiple.

[0032] Unless clearly indicated to the contrary, each aspect or embodiment defined by the claims can be combined with any other aspect or embodiment or embodiments. In particular, any feature indicated as preferred or advantageous can be combined with any other feature indicated as preferred or advantageous.

[0033] Term Explanation

[0034] As used herein, "hydrogen rich water" (HRW) or "hydrogen water" means water mixed with a certain amount of hydrogen gas. The maximum concentration of hydrogen gas dissolved in water at one atmosphere and 20°C is 1.6 ppm (i.e., the saturation concentration), i.e., 1.6 mg of hydrogen gas per kg of water. As used herein, the source of hydrogen gas can be electrolysis or cylinder gas, as known to those skilled in the art.

[0035] As used herein, the manner in which the hydrogen gas is introduced into the mashing vessel is not limited, so long as the hydrogen gas is allowed to diffuse in the water. For example, the gas inlet can be a nozzle or jet, etc. Alternatively, the hydrogen gas can be dissolved in water first, and the hydrogen water can be injected into the mashing vessel.

[0036] As used herein, "hydrogen rich water concentration" refers to the concentration of dissolved hydrogen in the hydrogen rich water initially introduced into the mashing vessel. While the escape of hydrogen gas and different methods of introducing hydrogen gas are taken into account, it is known to those skilled in the art that the desired concentration of dissolved hydrogen can be maintained by continuously adding hydrogen gas or hydrogen water, etc., to achieve a hydrogen rich water concentration of 80% or more, preferably 85% or more, more preferably 90% or more, and most preferably 95% to 99.9%. It should be noted that, due to the escape characteristics of hydrogen gas and the limitations of detection methods, the hydrogen rich water concentrations expressed herein (e.g., 0.3 ppm, 0.4 ppm, 0.5 ppm, 0.6 ppm, 0.7 ppm, 0.8 ppm, 0.9 ppm, 1.0 ppm, 1.1 ppm, 1.2 ppm, 1.3 ppm, 1.4 ppm, 1.5 ppm, 1.6 ppm, etc.) allow for a certain range of fluctuation. Those skilled in the art can know that a reasonable range of fluctuation around a certain hydrogen rich water concentration value can be considered to have the same degree of biological effect.

[0037] As used herein, "water" during mashing can be any aqueous solution or source, including tap water, purified water, purified water, or recycled water, without limitation. Even a mixture of water and cereal grains can be considered a suspension or aqueous solution.

[0038] The grain can be from any well-known cereal, such as barley, rice, sorghum, maize, millet, triticale, rye, oat and wheat. In a preferred embodiment of the present application, the cereal grain is barley grain. The grain can be grain of any barley variety. The cereal grain can have a relatively low water content before germination. For example, the cereal grain can have a water content of at most 30%, preferably at most 20%, such as at most 15%, such as 5 to 15%. Some cereal grains comprise a husk, while other cereal grains are huskless. Before the germination step, husked cereal grains can be treated to remove at least a part of the husk. Typically, if huskless cereal grains are used, no treatment to remove the husk is needed. Huskless cereals include, for example, huskless barley and wheat. In a preferred embodiment of the present application, the cereal grain used in the process of the present application is barley grain.

[0039] As used herein, the term "adjunct" refers to carbon-rich material added during brewing of beer. The adjunct can be ungerminated cereal grain, which can be milled together with the germinated grain prepared according to the present application. The adjunct can also be sugar syrup and the like.

[0040] As used herein, the term "moisture content", "water content" of a grain refers to the percentage of H2O w / w in the grain. Barley moisture determination can be performed as follows: first, weigh the empty weighing bottle W0, then weigh 5 g of barley. Grind with an EBC standard malt mill and load into the weighing bottle to a total weight W1. Weigh in an oven at 105°C for 2 hours, then weigh W2. Calculate the moisture content formula: Moisture content (%) = (W1-W2) / (W1-W0) x 100%.

[0041] As used herein, the term "germinated grain" refers to a grain that has developed a visible sprout, preferably a sprout of at least 1 mm, such as at least 2 mm, and a visible stem.

[0042] Malt manufacturing processes are well known in the art. Cereals can be germinated to alter their kernel structure, composition and enzyme content. The resulting malt has important uses in foodstuffs for animals and humans. Germinated barley is widely used in the brewing and distilling industries.

[0043] As used herein, the terms "soaking", "steeping", "immersion" refer to a process to increase the water content of the cereal kernel (about 40 to 45% (w / w)).

[0044] Mashing can be performed by any conventional method known to those skilled in the art. Mashing is performed to increase the water content of the grains and thereby to initiate germination. Mashing generally comprises one or more steps of immersing the cereal grains under moist conditions, for example, by immersing the cereal grains in water. This process is alternated with soaking or spraying, and aeration. The moisture in the barley can be increased from about 11 to 13% to about 40 to 45% in preparation for the increase in moisture and the next step of malting. This stage generally lasts for 10 to 45 hours. The conditions for mashing are not particularly limited, and publicly known conditions can be used. Specifically, soaking and air rest (also referred to as water cut-off) can be alternately performed, for example, one mashing, one air rest, two mashings, two air rests, three mashings, and three air rests can be repeatedly performed. By repeatedly performing mashing and air rest, sufficient moisture can be contained in the barley. At the end of the mashing process, a small rootlet appears, which converts the barley into green malt having a uniform water content. The green malt is then transferred to a germination vessel.

[0045] The mashing time varies depending on the kind or amount of the barley, and the temperature of the water, and cannot be set in general. As the time for one mashing, from the viewpoint of water absorption, 3 hours or more, more preferably 4 hours or more, more preferably 5 hours or more, further preferably 6 hours or more, and further preferably 8 hours or more are preferable. In addition, from the viewpoint of production efficiency, 20 hours or less, preferably 15 hours or less, and more preferably 10 hours or less are preferable. As the mashing temperature, 10 to 20°C, and more preferably 14 to 18°C are preferable.

[0046] As the time for air rest after one mashing, from the viewpoint of diffusion of water into the barley, 1 hour or more, more preferably 2 hours or more, further preferably 10 hours or more, further preferably 12 hours or more, and further preferably 15 hours or more are preferable. From the viewpoint of production efficiency, 24 hours or less, and more preferably 20 hours or less are preferable. In the air rest stage, the grains are aerated again by draining the water. The grains can be exposed to air. Note that at this time, the grains should not be immersed in water.

[0047] The time for the second mashing can be appropriately set with reference to the amount of water that has been absorbed by the barley, for example, 1 to 10 hours or so, preferably 1 to 6 hours, more preferably 1 to 5 hours, and more preferably 1 to 4 hours. In addition, the temperature for the second mashing is not particularly limited, and can be the same temperature as that for the first mashing, within the aforementioned example temperature range. The second air rest can be performed with reference to the first air rest, and the temperature and time can be appropriately set.

[0048] In a preferred embodiment, the mashing step, the mashing process is carried out using a multi-stage process of two mashes and two air rests, or three mashes and three air rests, to control the water content of the final grain to 39-45% (i.e. the mash degree). Using the above mashing process, the interior of the malted grain is provided with the appropriate amount of water to reactivate the enzymes present in the barley and start the life process of germination. The mash degree is calculated according to the formula: mash degree (%) = (mass of the grain after mashing - mass of the original barley + moisture content of the original barley) / mass of the grain after mashing.

[0049] As used herein, the term "start of germination" refers to the point in time at which the mashing phase is finished and the transfer to the germination device, i.e. the start of the germination, is initiated. The duration of the germination is calculated from the start of the germination, e.g. the duration of the germination can be calculated from the start of the germination until the beginning of the fractionation of the malted grain. In some embodiments, after the germination, the cereal grain has a water content of at least 30%, preferably at least 35%, more preferably at least 40% (e.g. 40% to 45%).

[0050] The germination of the cereal grain can be carried out at any feasible temperature. However, it can be preferred that the cereal grain is germinated at a temperature of at least 10°C. In particular, the cereal grain can be germinated at a temperature in the range of 10 to 25°C, preferably 12 to 25°C, preferably 14 to 20°C, preferably 14 to 18°C, preferably 16 to 18°C. It can be preferred that the cereal grain is not germinated prior to this germination step. It is worth mentioning that the germination rate of the malt and whether the root system after germination is robust or not is not a pain point for maltsters at the moment, which is different from the intention to improve the germination ability of seeds for agricultural sowing purposes.

[0051] During the germination process, the barley is spread on a sieve and continuously aerated. The embryo develops and chemical changes occur inside the barley. This process lasts 3.5 to 6 days. Finally, the embryo grows to almost the length of the barley and the roots wither, the malt at this stage is called "green malt". During the germination phase, water is added to keep the surface of the barley moist, which is called water spray. The water spray can be carried out in a manner known to the person skilled in the art, e.g. in the form of a spray to keep the surface moist.

[0052] Kiln drying or roasting refers to the step of drying malt. Green malt is heated in a drying kiln to reduce the water content and stop further growth. Most commercial drying kilns have a minimum degree of levelling of the green malt bed for efficient drying, and a turner machine can be used to mix, turn or level the green malt bed. Drying can be carried out at conventional temperatures, for example at least 40°C, at least 45°C, at least 65°C, at least 75°C, for example 80 to 90°C, for example 80 to 85°C. Kiln drying is usually carried out at elevated temperatures. An example of a kiln drying process is as follows: 16 hours at 45 to 65°C; 2 hours at 75 to 80°C; 3 hours at 83°C. The kiln drying step reduces the water content of the wet malt from about 40% to 4 to 5%.

[0053] As used herein, de-rooting refers to the removal of root sprouts produced during the malting process with a vibrating sieve. The final stage of malting is to produce a golden yellow, dry friable malt.

[0054] It is known to those skilled in the art that the quality indicators of high quality malt include the content of α-amino nitrogen, color and turbidity. Among them, the determination of the content of α-amino nitrogen is according to the indantrione colorimetric method (see Beer Malt Standard QB / T 1686-2008). The turbidity determination uses a beer turbidity meter. The colorimetric determination uses an ultraviolet-visible spectrophotometer.

[0055] The EBC color scale is established by the Institute of Brewing and European Brewing Convention, and is a recognized color grading method for beer, wort, caramel solution and similar colored liquids. Its visual units are between 2 and 27, with light yellow wort and light beer at the lower end of the color scale, and dark yellow wort, beer and caramel at the upper end of the color scale.

[0056] The agreement method saccharification test is a standard method recommended by the European Brewing Association (EBC) to evaluate the quality of malt. A small amount of wort is prepared by this method, and the quality of the malt used is evaluated thereby.

[0057] The α-amino nitrogen in malt is a low molecular nitrogen of amino acids, which is the main nitrogen source required for beer yeast metabolism. The higher the content of α-amino nitrogen, the stronger the yeast fermentation capacity, and the faster the beer fermentation speed.

[0058] Generally, malt with low color is suitable for brewing beer with low color. The color is related to the variety of barley and the malting process. The parameters of malting process such as steeping degree, moisture content at germination, temperature increase rate during germination, drying, and roasting temperature and time are usually positively correlated with the color. The color of pale malt is required to be 2.5 to 5.7 EBC. With the popularity of light beer, the malt color is paid more attention by the beer manufacturers. Some beer manufacturers even require the malt color to be as low as possible.

[0059] Turbidity is an index quantifying the clarity of wort. The lower the turbidity, the higher the quality of malt. Malt with high turbidity produces wort with high turbidity. The main substances causing the turbidity of wort are protein, polyphenol, dextrin, β-glucan and arabinoxylan, etc. In addition, some microbial metabolites and other factors can also cause the turbidity of wort. The turbid wort not only affects the filtration, but also leads to poor biological stability and flavor stability of beer after fermentation, thereby reducing the quality of beer. Therefore, malt with low turbidity is more popular among beer manufacturers.

[0060] As known by those skilled in the art, wort can be obtained by adding adjuncts to the obtained malt, and adding enzymes such as β-glucanase for gelatinization and saccharification as needed, removing bran and the like by filtration, adding hops for boiling, and removing solid components such as coagulated protein using a clarifying tank. In addition, known malt can be used in combination with the malt obtained by the method of the present application, and the proportions can be appropriately adjusted.

[0061] The malt obtained according to the present application can be used to produce a fermented beverage by adding yeast to wort obtained from raw materials including the malt to allow fermentation, and removing the yeast as needed using a filter or the like. The present application also provides a method for producing a fermented beverage characterized by using the malt obtained by the production method according to the present application. Herein, "fermented beverage" means a beverage fermented by yeast or the like, such as beer, beer-taste beverage, or whiskey, etc. These beverages are not particularly limited as long as the malt obtained according to the present application is used as a raw material, and can be produced according to known methods.

[0062] Raw materials and instruments

[0063] In addition to the glass instruments commonly used in laboratories, other equipment and materials include a stainless steel malting tank, a constant-temperature and constant-humidity incubator (purchased from Tokyo Rikakikai Co., Ltd.), a hydrogen-rich water electrolysis cup (purchased from Zhejiang Xinyankun Technology Co., Ltd.), and a hydrogen-rich water concentration detection kit (purchased from MIZ Co., Ltd., Japan).

[0064] The hydrogen-rich water concentration detection method: the hydrogen-rich water dissolves hydrogen content kit is used for detection, and the hydrogen content in the measured liquid can be accurately measured according to 0.1 ppm as a unit. The reagent is dropped into the hydrogen-rich water drop by drop. If the water contains hydrogen, for example, 0.5 ppm, the transparent water will turn blue instantly after each drop of 1 drop, and then it will recover to transparent color immediately. This is added dropwise for 5 drops, and the water can recover from blue to transparent color. When the 6th drop is added, the blue water does not recover to transparent color, which indicates that the hydrogen content of the measured liquid is 0.5 ppm. In addition, attention should be paid to the decay rate of the hydrogen concentration in the hydrogen-rich water. The inventors found that when the titration method is used to detect the hydrogen concentration, the hydrogen concentration does not change significantly after 30 minutes. When placed for 50 minutes, the hydrogen concentration decreases to half of the initial concentration. Therefore, electrolysis can be performed every 50 to 60 minutes.

[0065] The specific embodiments of the present application are described in detail below.

[0066] Example 1: Malting experiment of Yangnongpi No. 7

[0067] (1) Select full and complete Yangnongpi No. 7 barley.

[0068] (2) Washing: 200 g of barley was weighed and the surface impurities were washed.

[0069] (3) First steeping: hydrogen-rich water with a dissolved hydrogen concentration of 0.6 ppm was added to the steeping container to fully submerge the barley. The steeping container was placed in a constant temperature and humidity box, with a temperature of 15°C and a relative humidity of 90%. The first steeping time was 4 hours, and the hydrogen-rich water was replaced every 30 minutes to ensure the hydrogen-rich water concentration. The steeping container can be a steeping tank, and a known steeping tank can be used, preferably a stainless steel steeping tank. The shape and size of the steeping container can be appropriately adjusted according to the technical knowledge of those skilled in the art.

[0070] (4) First air rest: the first air rest time of the barley exposed to air was 12 hours.

[0071] (5) Second steeping: the same steps as the first steeping were repeated. The hydrogen-rich water concentration was 0.6 ppm. The second steeping time was 5 hours. The hydrogen-rich water was replaced every 30 minutes.

[0072] (6) Second air rest: the second air rest time of the barley exposed to air was 12 hours.

[0073] (7) Germination: the germination stage of the barley started from the end of the second air rest, and the germination time of the barley was calculated. The green malt was taken quantitatively every day during the germination period for measurement.

[0074] The germination stage is performed by maintaining the steeping degree at about 45% using hydrogen-rich water having a dissolved hydrogen concentration of 0.6 ppm. The hydrogen-rich water is added every 24 hours, for example, at 24 hours, 48 hours, and 72 hours. The germination stage is set as follows: from the start of germination to 24 hours, the germination temperature is set to 14°C; from 24 to 72 hours, the germination temperature is set to 15°C; from 72 to 96 hours, the germination temperature is set to 16°C; and from 96 to 110 hours, the germination temperature is set to 18°C.

[0075] The germination is completed until 110 hours (4 days + 14 hours), and green malt is obtained.

[0076] (8) The green malt is dried. The drying stage is set to 45 to 65°C for 16 hours, 75 to 80°C for 2 hours, and torrefaction at 83°C for 3 hours.

[0077] (9) Rooting: The malt after torrefaction is removed of the root and leaf sprouts, and weighed. The preparation of the malt is completed.

[0078] Example 2: The same procedure as in Example 1 is used. The difference is that hydrogen-rich water having a dissolved hydrogen concentration of 1.2 ppm is used in the first steeping, the second steeping, and the germination stage.

[0079] Example 3: The same procedure as in Example 1 is used. The difference is that hydrogen-rich water having a dissolved hydrogen concentration of 0.6 ppm is used only in the first steeping, and tap water is used in the second steeping and the germination stage.

[0080] Example 4: The same procedure as in Example 1 is used. The difference is that hydrogen-rich water having a dissolved hydrogen concentration of 0.6 ppm is used only in the second steeping, and tap water is used in the first steeping and the germination stage.

[0081] Example 5: The same procedure as in Example 1 is used. The difference is that hydrogen-rich water having a dissolved hydrogen concentration of 0.6 ppm is used only in the germination stage, and tap water is used in the first steeping and the second steeping.

[0082] Example 6: The same procedure as in Example 1 is used. The difference is that hydrogen-rich water having a dissolved hydrogen concentration of 0.3 ppm is used in the first steeping and the germination stage, and tap water is used in the second steeping.

[0083] Comparative Example: The same procedure as in Example 1 is used. The difference is that tap water is used in the first steeping, the second steeping, and the germination stage.

[0084] Each of the above examples and the comparative example can be set up in two parallel groups.

[0085] The malt prepared in Examples 1 to 6 and Comparative Example was made into a standard saccharified wort and the following quality indicators were measured, as shown in Table 1.

[0086] Overall, the use of hydrogen-rich water in the steeping and / or germination stage of the malting process can significantly improve the color, turbidity and alpha-amino nitrogen of the malt. There is no adverse effect on any of the quality indicators. Even at a low dissolved hydrogen concentration (Example 6), the color is reduced by 8.1%, the turbidity is reduced by 7.3%, and the alpha-amino nitrogen is increased by 2.8% compared to the malt produced using tap water.

[0087] The use of hydrogen-rich water in both the steeping and germination stages has the most significant effect on the improvement of color, turbidity and alpha-amino nitrogen. The biological effect of hydrogen-rich water in the steeping stage is more pronounced than in the germination stage. The use of hydrogen-rich water only in the germination stage slightly improves but does not significantly improve the color, turbidity and alpha-amino nitrogen. This can be seen from Examples 3 to 5. Furthermore, as can be seen from Examples 5 and 6, even at a low concentration of hydrogen-rich water (0.3 ppm) in the steeping stage, the effect on the improvement of color, turbidity and alpha-amino nitrogen is more significant than the use of a higher concentration of hydrogen-rich water (0.6 ppm) only in the germination stage.

[0088] The higher the concentration of hydrogen-rich water, the more pronounced the biological effect on the color, turbidity and alpha-amino nitrogen of the malt. Compared to Example 1, the color is further reduced by 14.3%, the turbidity is further reduced by 1.4%, and the alpha-amino nitrogen is further increased by 7.4% in Example 2. Maltsters can make a good trade-off between quality indicators and economics as needed.

[0089] Table 1 Quality indicators of malt produced in Examples 1 to 6 and Comparative Example

[0090]

[0091] Therefore, the present application can simultaneously improve multiple key quality indicators by using hydrogen-rich water in the malting process. The positive biological effect of hydrogen-rich water is particularly significant. The reduction in the color and turbidity of the malt meets the expectations of brewers for light-colored beer. The increase in the alpha-amino nitrogen content of the malt brings higher economic benefits to maltsters. The present application also provides the stage of use of hydrogen-rich water and the appropriate range of hydrogen-rich water concentration, which is an important guide for maltsters.

[0092] The preferred embodiments described in the specification are only preferred embodiments of the present application. The above embodiments are only used to illustrate the technical solutions of the present application and not to limit the present application. Any technical solutions obtained by logical analysis, reasoning or limited experiments based on the concept of the present application should be within the scope of the present application.

Claims

1. Use of a malt manufacturing method for simultaneously reducing malt color, reducing malt turbidity and increasing α-amino nitrogen content in malt, characterized by, The malt production method is: performing at least one steeping step on the grains, and in the at least one steeping step, the grains are immersed in hydrogen water with a dissolved hydrogen concentration of 0.3 to 1.2 ppm.

2. Use according to claim 1, characterized in that, In the at least one steeping step, the grains are immersed in hydrogen water with a dissolved hydrogen concentration of 0.6 to 1.2 ppm.

3. Use according to claim 1 or 2, characterized in that, After the steeping step, the grains start to germinate, and the surface of the grains is kept wet at least once using hydrogen water with a dissolved hydrogen concentration of 0.3 to 1.2 ppm.

4. Use according to claim 1 or 2, characterized in that, After the steeping step, the grains start to germinate, and the surface of the grains is kept wet at least once using hydrogen water with a dissolved hydrogen concentration of 0.6 to 1.2 ppm.

5. The use according to claim 1, characterized in that, The temperature of the at least one steeping step is in the range of 10 to 20℃.

6. Use according to claim 1, characterized in that, The number of steeping steps is two, and both the first steeping step and the second steeping step immerse the grains in hydrogen water with a dissolved hydrogen concentration of 0.3 to 1.2 ppm.

7. The use according to claim 1, characterized in that, The time of the at least one steeping step lasts for more than 3 hours.

8. Use according to claim 3, characterized in that, The temperature of the germination is in the range of 12 to 25℃.

9. Use according to claim 3, characterized in that, Hydrogen water is used at least once every 20 to 25 hours from the start of the germination. Hydrogen water is used at least once every 20 to 25 hours from the start of the germination.

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