AU2014276195B2

AU2014276195B2 - Fermented malt beverage and production method therefor

Info

Publication number: AU2014276195B2
Application number: AU2014276195A
Authority: AU
Inventors: Teppei Kurokawa; Kiyohito Sato
Original assignee: Asahi Breweries Ltd
Current assignee: Asahi Breweries Ltd
Priority date: 2013-06-03
Filing date: 2014-04-09
Publication date: 2017-08-03
Anticipated expiration: 2034-04-09
Also published as: JP6604849B2; KR102221000B1; JP6923617B2; NZ714121A; JP2021168694A; CN105264060A; AU2014276195A1; JPWO2014196265A1; KR20160013053A; JP2020000260A; WO2014196265A1; JP2023101727A

Abstract

The present invention provides: a fermented malt beverage having a remarkably low sugar content regardless of the amount of malt used relative to starchy material; and a method for producing said fermented malt beverage. This production method for a fermented malt beverage is characterized by: using malt as a raw material; adding glucoamylase in at least either a mashing step or a fermentation step; and adding transglucosidase in the fermentation step. This fermented malt beverage is characterized by the malt content being 65%-100% by mass of the fermentation raw material and by the sugar content being less than 0.5 g/100 mL.

Description

1

DESCRIPTION

FERMENTED MALT BEVERAGE AND PRODUCTION METHOD THEREFOR

TECHNICAL FIELD

[0001]

The present invention relates to a production method for a fermented malt beverage having an adequately reduced sugar content even in those cases when the proportion of malt used in the fermentation raw materials is increased, and also relates to a fermented malt beverage produced using the production method.

BACKGROUND ART

[0002]

In recent years, changes in the health awareness and preferences of consumers have resulted in increased consumer demand for beer-tasting beverages having low sugar content. Beer-tasting beverages are carbonated beverages having flavor, taste and texture that are the same as, or similar to, those of beer. In the case of beer-tasting beverages obtained by fermenting a fermentation raw material, by reducing the amount of non-assimilable sugar in the fermentation liquid, the sugar content in the beer-tasting beverage that represents the final product can be reduced. Accordingly, by increasing the proportion of liquid sugars and the like having a low non-assimilable sugar content in the fermentation raw materials, the sugar content can be reduced, but in those cases when the proportion of grain raw materials is high, although the aroma of the grain and the full-bodied sensation can be enhanced, the sugar content tends to increase.

[0003] 2

One known method for producing a beer-tasting beverage having a low sugar content is a method in which a glucoamylase and/or pullulanase is added during the raw material charging step or the fermentation step. As a result of the actions of these enzymes, the majority of the starch that contributes to the sugar content contained within the final product can be decomposed into sugars that are assimilable by yeast. However, non-assimilable branched-chain sugars such as isomaltose cannot be converted to assimilable sugars by these enzymes, and remain in the final product. As a result, this method has been unable to reduce the sugar content to very low levels.

[0004]

Further, in another known method, the action of α-glucosidase (an alternative name for transglucosidase) is used in the fermentation step to produce glucose as an assimilable sugar and increase the true fermentation degree, thus reducing the amount of non-assimilable sugars in the final product (for example, see Patent Document 1). However, simply adding a transglucosidase during the fermentation has been unable to adequately reduce the amount of non-assimilable sugars in the final product.

[0005]

In this manner, although a number of methods for reducing the sugar content of beer-tasting beverages are known, in those cases where a high proportion of starch raw materials having a comparatively high non-assimilable sugar content is used, none of these known methods has been capable of adequately reducing the sugar content. In particular, a malting step of germinating barley increases the amount of branched-chain sugars (for example, see Non-Patent Document 1), and therefore among current beertasting beverages that use a large proportion of malt, no beverage exists in which the sugar content has been reduced to less than 0.5 g/100 mL.

[0006] 2014276195 12M2017 3

Transglucosidase produces glucose via a hydrolysis reaction, but when the substrate concentration is high, catalyzes a transglucosylation reaction. For example, in a beer-tasting beverage which uses a malt as a raw material and is produced via a fermentation step, by adding a transglucosidase prior to the heat treatment in the 5 charging step, high concentrations of isomaltooligosaccharides such as isomaltose and panose can be incorporated in the product, and as a result, the full-bodied taste can be enhanced (for example, see Patent Document 2). PRIOR ART LITERATURE Patent Documents 10 [0007]

Patent Document 1: Japanese Unexamined Patent Application, First Publication No. 2002-253197

Patent Document 2: Japanese Unexamined Patent Application, First Publication No. 2002-199873 15 Non-Patent Document [0008]

Non-Patent Document 1: Allosio-Ouarnier and 3 others, Journal of The Institute of Brewing, 2000, Volume 106, Issue 1, pages 45 to 52.

[0008A] 20 Any discussion of documents, acts, materials, devices, articles or the like which has been included in the present specification is not to be taken as an admission that any or all of these matters form part of the prior art base or were common general knowledge in the field relevant to the present disclosure as it existed before the priority date of each of the appended claims. 25 [0008B]

Throughout this specification the word "comprise", or variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated element, integer or step, or group of elements, integers or steps, but not the exclusion of 30 any other element, integer or step, or group of elements, integers or steps. 2014276195 12 Jul2017 4

DISCLOSURE OF INVENTION

[0009]

The present invention relates to providing a fermented malt beverage having a 5 remarkably low sugar content regardless of the proportion of malt used within the fermentation raw materials, as well as providing a method for producing the fermented malt beverage.

[0010]

As a result of intensive research the inventors of the present invention 10 discovered that in the production of a fermented malt beverage, by adding a glucoamylase during at least one of the charging step and the fermentation step, and adding a transglucosidase in the fermentation step, a fermented malt beverage having a markedly reduced sugar content could be produced even when the proportion of malt used, in the fermentation raw materials was increased, and they were therefore able to 15 complete the present invention.

SUMMARY

[0010A]

In one aspect of the invention there is provided a production method for a 20 fermented malt beverage, wherein a malt in an amount of 65 to 100% by mass of a fermentation raw material is used as a raw material, a glucoamylase is added during at least one of a charging step and a fermentation step, and a transglucosidase is added in the fermentation step, thereby reducing an 25 apparent extract of the beverage to -0.60% by mass or less. 2014276195 12M2017

4A

[0010B]

In another aspect of the invention there is provided a fermented malt beverage, in which an amount of malt used is from 65 to 100% by mass of a fermentation raw material, in which a sugar content is less than 0.5 g/100 mL, and an apparent extract is -5 0.60% by mass or less.

[0011]

The present invention adopts the following aspects. (1) A production method for a fermented malt beverage, wherein a malt is used as a raw material, a glucoamylase is added during at least one of the charging step and 10 the fermentation step, and a transglucosidase is added in the fermentation step. (2) The production method for a fermented malt beverage disclosed in (1), wherein the transglucosidase is added in an amount of at least 3 U/g relative to the extract concentration. (3) The production method for a fermented malt beverage disclosed in (1) or 15 (2), wherein the fermentation step is performed at 5 to 15°C. (4) The production method for a fermented malt beverage disclosed in any one of (1) to (3), wherein the amount of malt used is from 65 to 100% by mass of the fermentation raw materials. 5 (5) The production method for a fermented malt beverage disclosed in any one of (1) to (4), wherein the sugar content in the fermented malt beverage is less than 0.5 g/100 mL. (6) A fermented malt beverage in which the amount of malt used is from 65 to 100% by mass of the fermentation raw materials, and in which the sugar content is less than 0.5 g/100 mL.

Effects of the Invention [0012]

By employing the production method for a fermented malt beverage according to the present invention, a fermented malt beverage having a remarkably low sugar content can be produced regardless of the proportion of malt used within the fermentation raw materials.

BEST MODE FOR CARRYING OUT THE INVENTION

[0013]

In the present invention and the description of this application, a fermented malt beverage refers to a beverage which uses a malt as a raw material, and is produced via a fermentation step. A fermented malt beverage produced using the production method for a fermented malt beverage according to the present invention (hereafter also referred to as simply "the production method according to the present invention") may be an alcoholic beverage, or a so-called non-alcoholic beverage or low-alcohol beverage with an alcohol content of less than 1 % by volume. In addition, the fermented malt beverage may also be a liqueur obtained by mixing a beverage produced via a fermentation step using a malt as a raw material with an alcohol-containing distilled liquid. The alcohol- 6 containing distilled liquid refers to a solution containing alcohol that is obtained by a distillation operation, and may use a liquid generally classified as a spirit. The fermented malt beverage produced using the production method according to the present invention is preferably a beer-tasting beverage. Specific examples of such beverages include beer, happoshu (low-malt beer), and liqueurs obtained by mixing a beer or low-malt beer with an alcohol-containing distilled liquid.

[0014]

The production method according to the present invention includes a charging step and a fermentation step, wherein a malt is used as a raw material, a glucoamylase is added during at least one of the charging step and the fermentation step, and a transglucosidase is added in the fermentation step. More specifically, by adding the glucoamylase to the preparation tank used for saccharifying the raw materials and/or the fermentation tank, and adding the transglucosidase to the fermentation tank, the reaction of decomposing the sugars in the raw materials into yeast-assimilable sugars is accelerated during the production of the fermented malt beverage. As a result, the amount of non-assimilable sugars in the raw materials is reduced, and a fermented malt beverage having a low sugar content can be produced. By employing the production method according to the present invention, the residual amounts of non-assimilable isomaltooligosaccharides such as isomaltose and nigerose can be reduced particularly dramatically. Isomaltooligosaccharides are usually not assimilated by yeast, and are therefore retained in the final product as sugar components. However, in the production method according to the present invention, by adding the glucoamylase and the transglucosidase with appropriate timing, they are decomposed into glucose, which is then assimilated by the yeast during fermentation, resulting in a decrease in the amount of residual sugars in the final product. 7 [0015]

There are no particular limitations on the glucoamylase used in the present invention, provided it is an enzyme having a catalytic activity that severs the nonreducing end of a starch to generate glucose, and any of the glucoamylases derived from various organisms can be used. For example, any of the commercially available glucoamylases may be used, or a combination of these enzymes may also be used.

[0016]

The starch decomposition action of the glucoamylase operates during both the charging step and the fermentation step. Accordingly, in the production method according to the present invention, the glucoamylase should be added during at least one of the charging step and the fermentation step, and may also be added during both steps.

[0017]

When the glucoamylase is added during the charging step, there are no particular limitations on the addition period for the glucoamylase, provided that the enzyme reaction of the glucoamylase that is added prior to the completion of the charging step is able to proceed satisfactorily. For example, the glucoamylase may be added together with the fermentation raw materials such as the malt during preparation of the mash, or may be added during the saccharification reaction. In the present invention, in order to ensure that the enzyme reaction of the glucoamylase proceeds satisfactorily, the glucoamylase is preferably added either during preparation of the mash, or at an early stage in the charging step, and is more preferably added during preparation of the mash. Similarly, when it is added during the fermentation step, there are no particular limitations on the addition period for the glucoamylase, provided that the enzyme reaction of the glucoamylase that is added prior to the completion of the fermentation step is able to proceed satisfactorily, but the glucoamylase is preferably added no later 8 than the start of the fermentation, and is more preferably either added at the start of the fermentation, or added to the cooled wort prior to the start of fermentation.

[0018]

There are no particular limitations on the transglucosidase used in the present invention, provided it is an enzyme having a catalytic activity that decomposes sugars via a hydrolysis reaction, and any of the transglucosidases derived from various organisms can be used. For example, any of the commercially available transglucosidases may be used, or a combination of these enzymes may also be used.

[0019]

As mentioned above, whether the transglucosidase catalyzes a transglucosylation reaction or a hydrolysis reaction is dependent on the substrate concentration. Because the substrate concentration is high in the charging step, the equilibrium tends to shift toward the transglucosylation reaction. As a result, in order to ensure decomposition of the non-assimilable sugars such as isomaltooligosaccharides, the transglucosidase must be added during the fermentation step. There are no particular limitations on the addition period for the transglucosidase, provided that the enzyme reaction of the transglucosidase that is added prior to the completion of the fermentation step is able to proceed satisfactorily, and the transglucosidase may be added prior to the start of the fermentation, or may be added to the fermenting liquid during the fermentation step. Further, the entire amount of transglucosidase used may be added in a single addition, or the transglucosidase may be added over a plurality of additions.

[0020]

If the transglucosidase is added during the initial stages of fermentation when the substrate concentration is high, then because isomaltooligosaccharides are produced by the transglucosylation reaction, fermentation delays are more likely to occur, and the 9 amount of residual sugar components not consumed during the fermentation tends to increase, meaning it is difficult to achieve a satisfactory reduction in the residual sugar content in the final product. However, in the production method of the present invention, because a glucoamylase is used in combination with the transglucosidase, fermentation delays are less likely to occur than in those cases where a transglucosidase is used alone, and the amount of residual sugar components is able to be reduced significantly more than has conventionally been possible.

[0021]

There are no particular limitations on the amounts added of the glucoamylase and the transglucosidase, provided the amounts are sufficient to ensure satisfactory progression of the respective enzyme reactions, and the amounts may be determined appropriately with due consideration of factors such as the type and potency of the enzymes used, the reaction temperatures, and the reaction times. For example, by extending the fermentation time and the subsequent storage period, the amounts of enzyme required to reduce the sugar content in the final product to a value within the desired range can be reduced. For example, when the fermentation time and storage period are set to the types of periods typically used in the production of beer or low-malt beer, the amount of the transglucosidase added is preferably at least 3 U/g, more preferably at least 30 U/g, and still more preferably 80 U/g or greater, relative to the concentration of the grain-derived extract (the soluble nonvolatile residue). When the fermentation and storage periods are lengthened beyond those typically used, the amount added of the transglucosidase may be less than 3 U/g.

[0022]

With the exceptions of adding the glucoamylase during at least one of the charging step and the fermentation step, and adding the transglucosidase in the 10 fermentation step, the production method according to the present invention may employ typical methods used for producing alcoholic fermented malt beverages such as beer and low-malt beer. For example, the production method according to the present invention can be performed via charging, fermentation, storage, filtration and filling steps.

[0023]

First, in the charging step, a wort is prepared from the fermentation raw materials including a malt. Specifically, first, a malt or a ground product thereof, any other fermentation raw materials besides malt that may be added according to need, and a raw water are added to the preparation tank and mixed to prepare a mash. The mash preparation can be performed using normal methods, such as by holding the mash at a temperature of 35 to 70°C for a period of 20 to 90 minutes. Subsequently, the temperature of the mash is gradually increased, and by holding the mash at a prescribed temperature for a certain period of time, the enzymes derived from the malt and the enzymes added to the mash can be used to saccharify the starch. Following this saccharification treatment, the mash is held at 76 to 78°C for about 10 minutes, and is then filtered in a wort filtration tank to obtain a transparent wort.

[0024]

The malt used in the present invention may be a malt prepared by germinating barley or the like using a typical malting treatment. Specifically, the malt can be produced by immersing harvested barley, wheat, or oats or the like in water, and following an appropriate degree of germination, drying the germinated grains in hot air. The malt may be ground using normal methods.

[0025]

Examples of other fermentation raw materials besides the malt include starch raw materials such as barley, wheat, corn starch, com grit, rice and sorghum, and sugar raw 11 materials such as liquid sugar and granulated sugar. In this description, liquid sugar describes one produced by decomposing and saccharifying a starch with an acid or a saccharification enzyme, and includes mainly glucose, maltose, and maltotriose and the like.

[0026]

In the production method according to the present invention, even when the proportion of starch raw materials is high within the fermentation raw material, the sugar content in the final product can be reduced markedly. As a result, by using the production method according to the present invention, the proportion of starch raw materials, and particularly malt, used within the fermentation raw material can be increased without increasing the sugar content. In order to enable the effects of the production method according to the present invention to be more effectively realized, it is preferable that only starch raw materials are used for the fermentation raw material, and the proportion of malt used relative to the total fermentation raw material is preferably at least 50%, and more preferably from 65 to 100%. Generally, a higher proportion of malt in the fermentation raw material tends to result in a higher residual non-assimilable sugar content in the final product, but by using the production method according to the present invention, a fermented malt beverage having a sugar content of less than 0.5 g/100 mL can be produced even when the proportion of malt used in the fermentation raw material is 100%.

[0027]

Besides the fermentation raw materials and the glucoamylase, other saccharification enzymes such as α-amylase or pullulanase, and enzyme agents such as protease may be added to the mash according to need. In addition, spices, herbs, and 12 fruit and the like may also be added, provided they do not inhibit the effects provided by the present invention.

[0028]

The temperature and the time period for the saccharification treatment may be determined appropriately with due consideration of factors such as the type of enzymes added such as the glucoamylase, the quantity of the mash, and the quality required for the targeted fermented malt beverage. For example, the saccharification treatment may be performed by maintaining a temperature of 60 to 72°C for a period of 30 to 90 minutes.

[0029]

Alternatively, a mash prepared by mixing a portion of the malt, some or all of the barley, and hot water in a preparation kettle may be subjected to a saccharification treatment, subsequently mixed with the mash that has been saccharified in the preparation tank described above, and then filtered in the wort fdtration tank to obtain a wort.

[0030]

The obtained wort is then boiled. The boiling method and conditions may be determined as appropriate. By adding herbs or flavorings either before the boiling treatment or during the boiling treatment, a fermented malt beverage having the desired flavor can be produced.

[0031]

In the present invention, hops are preferably added either before the boiling treatment or during the boiling treatment.

By conducting the boiling treatment in the presence of hops, the flavor and aroma of the hops can be extracted. The amount of hops added, the mode of addition (for 13 example, splitting the addition into several portions) and the boiling conditions may be determined as appropriate.

[0032]

The boiled wort is transferred to a settling tank called a whirlpool, and the hop dregs and curdled protein and the like generated as a result of the boiling are preferably removed. Subsequently, the wort is cooled with a plate cooler to an appropriate fermentation temperature. The cooled wort may then be supplied without further modification to the fermentation step, or the extract concentration may first be adjusted to a desired level, and the cooled wort then supplied to the fermentation step.

[0033]

Subsequently, in the fermentation step, the cooled wort is inoculated with a yeast and transferred to a fermentation tank to allow the fermentation to proceed. There are no particular limitations on the yeast used in the fermentation, and the yeast may be selected appropriately from among yeasts typically used in the production of alcoholic beverages. The yeast may be either a top fermenting yeast or a bottom fermenting yeast, but in terms of the ease of use within large-scale brewing facilities, a bottom fermenting yeast is preferable. In those cases where the transglucosidase is added prior to the start of the fermentation, the transglucosidase may be added to the cooled wort prior to the yeast inoculation, added to the cooled wort following adjustment of the extract concentration but prior to the yeast inoculation, or added together with the yeast.

[0034]

The residual sugar components in the fermented malt beverage include not only isomaltooligosaccharides, but also glycerol. Glycerol is produced by the yeast during fermentation, and in the case of a beer-tasting beverage, is typically included in an amount of about 1,000 to 2,000 ppm. As illustrated in the following reference example, 14 the glycerol content increases in proportion with the fermentation temperature, and therefore from the viewpoints of the glycerol content and the flavor, the fermentation temperature is preferably from 5 to 15°C, and more preferably from 5 to 13°C.

[0035]

Moreover, by subsequently performing a storage step by maturing the obtained fermented liquid in a storage tank, and storing and stabilizing the liquid at a low temperature of about 0°C, and then performing a filtration step by filtering the matured fermented liquid to remove the yeast and proteins and the like, the targeted fermented malt beverage can be obtained. Further, in the steps following the fermentation step using yeast, beverages defined as liqueurs in the Liquor Tax Act can be produced, for example by mixing spirits with the fermented liquid. The obtained fermented malt beverage is usually bottled in a filling step, and then shipped as a final product.

EXAMPLES

[0036]

The present invention is described below in further detail using a series of examples and a reference example, but the present invention is in no way limited by the examples presented below.

[0037] <Measurement of Amounts of Various Sugars>

The amounts (mg/L) of various sugars in the wort or the fermented malt beverage were measured by high performance liquid chromatography using a mass analyzer to detect the separated disaccharides, trisaccharides and tetrasaccharides, with the amounts calculated based on the surface areas of the obtained peaks. For the measurement apparatus, an L-2100 pump, an L-2200 autosampler, an L-2300 column oven (all 15 manufactured by Hitachi High-Technologies Corporation), and an API3000 mass analyzer (manufactured by AB Sciex Pte., Ltd.) were used.

[0038]

When measuring the disaccharides, the high performance liquid chromatography mass analysis was performed under the following conditions.

Detection: Electrospray Ionization (ESI) positive, Multiple Reaction Monitoring (MRM) m/z 360.0 —► 163.1, column: Hypercarb (2.1 mm x 150 mm, 3 pm, manufactured by Thermo Scientific, Inc.), column temperature: 60°C, flow rate: 0.2 mL/min, mobile phase A: 10 mmol/L ammonium acetate water (0.1% by volume acetic acid), mobile phase B: methanol, gradient conditions: 0 to 10 minutes (mobile phase B concentration: 0% by volume) —► 10 to 25 minutes (mobile phase B concentration: 3% by volume) —> 25 to 40 minutes (mobile phase B concentration: 13% by volume) —► 40 to 50 minutes (mobile phase B concentration: 18% by volume) —► 50 to 60 minutes (mobile phase B concentration: 40% by volume) —► 60 to 70 minutes (mobile phase B concentration: 80% by volume) —> 70 to 85 minutes (mobile phase B concentration: 0% by volume).

[0039]

When measuring the trisaccharides, the analysis conditions included ESI positive detection, and MRM m/z 522.5 —» 325.1.

When measuring the tetrasaccharides, the analysis conditions included ESI positive detection, and MRM m/z 684.5 —► 325.1.

[0040] <Measurement of Wort Fermentation Degree>

Measurement of the wort fermentation degree was conducted in accordance with the method prescribed (7.3 and 8.11: Final Fermentation Degree) in the revised analysis 16 methods of the Brewery Convention of Japan (published by the Brewing Society of Japan). In other words, the yeast was added to the wort, and following fermentation of all of the fermentable extract, the extract concentration was measured, and the fermentation degree was calculated from the thus obtained measured value and the previously measured extract concentration of the original wort (namely, the wort prior to fermentation).

Final fermentation degree (%) = ([extract concentration of original wort] -[extract concentration after fermentation]) / [extract concentration of original wort] x 100 [0041] [Example 1] A beer-tasting beverage was produced using a 200 L-scale preparation facility. First, the preparation tank was charged with 28 kg of a ground malt, 196 L of raw water, and 20 U/g of a glucoamylase (product name: Gluczyme NLP, manufactured by Amano Enzyme Inc.) relative to the ground malt, and a saccharification liquid was produced in accordance with normal methods. The thus obtained saccharification liquid was filtered using a wort filtration tank, hops were added to the obtained wort, and the wort was then boiled. Subsequently, the wort was transferred to a settling tank, and following separation and removal of the sediment, the wort was cooled to about 10°C. Following adjustment of the extract concentration of the cooled wort to 9.4% by mass, a transglucosidase (product name: Transglucosidase L, manufactured by Amano Enzyme Inc.) was added to a test sample of the wort in an amount of 80 U/mL relative to the cooled wort, whereas no transglucosidase was added to a control sample. The fermentation liquid of each sample was introduced into a different fermentation tank, inoculated with a beer yeast, fermented at about 10°C for 7 days, and then matured in a 17 storage tank for 8 days to obtain a beer-tasting beverage (alcohol content: 3.8% by volume).

[0042]

For each of the obtained beer-tasting beverages, the amounts of isomaltose, kojibiose and nigerose were measured. The measurement results are shown in Table 1.

In the test sample in which the transglucosidase was added in the fermentation step, the amount of each sugar was less than 5 mg/L, and compared with the control sample to which the transglucosidase was not added, the amounts of the sugars were markedly reduced. Further, the sugar content of the test sample was 0.4 g/100 mL. Based on these results, it was clear that by using the production method according to the present invention, a low-calorie beer-tasting beverage with a low sugar content could be produced, even when the proportion of malt used was 100%.

[0043] [Table 1]

Control sample (mg/L) Test sample (mg/L) Isomaltose 497 <5 Kojibiose 105 <5 Nigerose 174 <5 [0044] [Example 2]

With the exception of measuring the amounts of the disaccharides, trisaccharides and tetrasaccharides in the fermentation liquid every day from the start of fermentation through to the completion of fermentation, and in the beer-tasting beverage after completion of the maturation, beer-tasting beverages were obtained in the same manner as Example 1. The measurement results for the control sample are shown in Table 2, and 18 the measurement results for the test sample are shown in Table 3. In Tables 2 and 3, the "wort" refers to the cooled wort prior to yeast inoculation in which the extract concentration has been adjusted to 9.4% by mass. Further, the sugars from trehalose to cellobiose are disaccharides, the sugars from melezitose to maltotriose are trisaccharides, and maltotetraose is a tetrasaccharide.

[0045] [Table 2]

Amount (mg/L) Control sample Wort Fermentation day 1 Fermentation day 2 Fermentation day 3 Fermentation day 5 Fermentation day 6 Fermentation day 7 After completion of maturation Trehalose 65 63 49 45 39 35 38 34 Isomaltose 336 433 427 476 505 500 499 495 Kojibiose 120 120 107 107 97 96 96 89 Maltose 257 99 27 <5 <5 <5 <5 <5 Neotrehalose 75 72 63 69 71 71 75 70 Nigerose 169 167 157 168 172 171 172 168 Gentiobiose 81 95 120 146 148 140 131 112 Cellobiose 14 15 15 16 18 18 18 17 Melezitose 45 19 12 9 7 7 6 6 Isomaltotriose <5 <5 6 7 7 7 <5 6 Panose 211 162 102 81 74 72 78 68 Maltotriose 27 21 16 13 11 9 12 7 Maltotetraose 7 8 8 7 9 8 6 9 Total 1405 1273 1107 1143 1156 1134 1130 1079 [0046] 19 [Table 3]

Amount (mg/L) Test sample Wort Fermentation day 1 Fermentation day 2 Fermentation day 3 Fermentation day 5 Fermentation day 6 Fermentation day 7 After completion of maturation Trehalose 65 65 57 47 42 38 37 36 Isomaltose 336 645 480 330 32 <5 <5 <5 Kojibiose 120 119 99 80 32 <5 <5 <5 Maltose 257 8 <5 <5 <5 <5 <5 <5 Neotrehalose 75 8 <5 <5 <5 <5 <5 <5 Nigerose 169 170 149 125 54 7 <5 <5 Gentiobiose 81 99 134 145 155 135 108 30 Cellobiose 14 16 16 16 17 15 12 <5 Melezitose 45 29 23 13 8 7 <5 <5 Isomaltotriose <5 <5 <5 <5 <5 <5 <5 <5 Panose 211 128 45 22 11 10 8 5 Maltotriose 27 <5 6 <5 <5 <5 <5 <5 Maltotetraose 7 <5 <5 <5 <5 <5 <5 <5 Total 1405 1286 1008 776 350 211 164 71 [0047]

In the control sample, among the sugars shown in Table 2, only maltose decreased to an amount of less than 5 mg/L after day 3 of the fermentation, whereas the amounts of the other sugars did not greatly change during the fermentation and maturation. In contrast, in the test sample, although the amount of isomaltose had increased after day one of fermentation, it decreased rapidly thereafter, and after day 5 of the fermentation, had decreased to less than 5 mg/L in a similar manner to the control 20 sample. Moreover, the amounts of maltose, neotrehalose, maltotriose and maltotetraose had all decreased to less than 5 mg/L after day 2 of fermentation, and the amounts of cellobiose and melezitose had decreased to less than 5 mg/L by the completion of the maturation. Further, the amount of gentiobiose also started to decrease after day 6 of the fermentation, and the amount continued to decrease during the maturation period following completion of the fermentation. As a result, whereas the total amount of sugars shown in Table 2 was 100 mg/100 mL for the control sample, the total amount was as small as 7 mg/100 mL in the test sample.

[0048] [Example 3]

With the exception of adding 0, 3 or 300 U/mL of transglucosidase (product name: Transglucosidase L, manufactured by Amano Enzyme Inc.) to the cooled wort for which the extract concentration had been adjusted to 9.4% by mass, beer-tasting beverages were produced in the same manner as Example 1. For each of the beer-tasting beverages, the amounts of isomaltose, kojibiose and nigerose were measured. The measurement results are shown in Table 4. In the beer-tasting beverage to which 3 U/mL of the transglucosidase had been added to the cooled wort in the fermentation step, the amount of isomaltose had decreased to less than 5 mg/L. In the beer-tasting beverage to which 300 U/mL of the transglucosidase had been added to the cooled wort in the fermentation step, the amounts of all three sugars had decreased to less than 5 mg/L.

[0049] [Table 4]

Amount (mg/L) Amount of transglucosidase added (U/mL) 0 3 300 Isomaltose 580 <5 <5 21

Kojibiose 128 17 <5 Nigerose 275 43 <5 [0050] [Example 4] A beer-tasting beverage was produced using a 200 L-scale preparation facility. First, the preparation tank was charged with 40 kg of a ground malt and 160 L of raw water, and a saccharification liquid was produced in accordance with normal methods. The thus obtained saccharification liquid was filtered using a wort filtration tank, hops were added to the obtained wort, and the wort was then boiled. Subsequently, the wort was transferred to a settling tank, and following separation and removal of the sediment, the wort was cooled to about 10°C. Following adjustment of the extract concentration of the cooled wort to 9.4% by mass, a glucoamylase (product name: Gluczyme NLP, manufactured by Amano Enzyme Inc.) and a transglucosidase (product name: Transglucosidase L, manufactured by Amano Enzyme Inc.) were added to achieve the amounts shown in Table 5. The fermentation liquid of each sample was introduced into a different fermentation tank, inoculated with a beer yeast, fermented at about 10°C for 7 days, and then matured in a storage tank for 7 days to obtain a beer-tasting beverage.

[0051]

The apparent extract (% by mass) of each beer-tasting beverage was measured. The measurement results are shown in Table 5. The apparent extract refers to the extract of the beer-tasting beverage, represented by the sucrose concentration (usually in terms of % by mass) of an aqueous solution of sucrose having the same specific gravity as the beverage at 20°C. Because the beverage contains alcohol, the apparent extract differs from the true meaning of extract (soluble nonvolatile residue = true extract). The 22 apparent extract also includes extract components other than sugars such as dietary fiber and ash and the like. However, in the present example, because the conditions were identical except for the enzymes used, it can be assumed that the components other than sugars in each of the beer-tasting beverages were the same.

[0052] [Table 5]

Sample Control Test 1 Test 2 Glucoamylase (U/mL) 0 0 0.35 Transglucosidase (U/mL) 0 80 80 Apparent extract (% by mass) 1.74 -0.44 -0.60 [0053]

These results confirmed that the samples of Tests 1 and 2 containing the added enzyme(s) had a reduced apparent extract and a lower sugar content than the control sample to which neither enzyme was added. The Test 2 sample to which both transglucosidase and glucoamylase had been added exhibited a more marked reduction in the apparent extract and a larger reduction in the sugar content than the Test 1 sample to which only the transglucosidase had been added.

[0054]

Four specialist panelists performed a sensory evaluation of the grain-like aroma and the full-bodied sensation of the Test 2 sample. The evaluation was performed by specifying a score of 2 points for a commercially available low-malt beer having a proportion of malt of less than 25% and a sugar content of less than 0.5 g/100 mL, and then evaluating the sample against a 5-step scale from 1 to 5 points (wherein a score of 1 represents almost no grain-like aroma or full-bodied sensation, and a score of 5 23 represents extremely strong grain-like aroma or full-bodied sensation). The results for the evaluations of the Test 2 sample yielded a grain-like aroma evaluation of 3.75 and a full-bodied sensation evaluation of 3.75, both of which were significantly higher than the results for the commercially available low-malt beer used for comparison. In particular, the taste of the Test 2 sample had no unpleasant aromas resulting from the addition of the enzymes or derived from the raw materials such as the secondary raw materials, and exhibited a favorable beer-like flavor. Based on these results, it was evident that the production method according to the present invention was able to produce a beer-tasting beverage having an excellent grain-like aroma and excellent body by increasing the proportion of malt used without increasing the sugar content.

[0055] [Reference Example 1] A beer-tasting beverage was produced using a 200 L-scale preparation facility. First, the preparation tank was charged with 40 kg of a ground malt and 160 L of raw water, and a saccharification liquid was produced in accordance with normal methods. The thus obtained saccharification liquid was filtered using a wort filtration tank, hops were added to the obtained wort, and the wort was then boiled. Subsequently, the wort was transferred to a settling tank, and following separation and removal of the sediment, the wort was cooled to about 5°C, 10°C or 15°C. Following adjustment of the extract concentration of these cooled worts to 7.3% by mass, each wort was introduced into a different fermentation tank, inoculated with a beer yeast, fermented at about 5°C, 10°C or 15°C for 7 days, and then matured in a storage tank for 7 days to obtain a beer-tasting beverage.

The glycerol concentration of each of the obtained beer-tasting beverages was quantified using a commercially available glycerol quantification kit (product name: 24

Glycerol Colorimetric Assay Kit, manufactured by Cayman Chemical Company). Moreover, a sensory evaluation of each beer-tasting beverage was conducted by 5 specialist panelists. The results of the glycerol measurements and the sensory evaluations are shown in Table 6. Within the sensory evaluation results, the numbers following the various comments indicate the number of panelists who made that particular comment. A tendency was observed for a higher glycerol concentration within the beer-tasting beverage as the fermentation temperature was increased.

[0056] [Table 6]

Sample Fermentation temperature 5°C 10°C 15°C Glycerol concentration (ppm) 708 805 1117 Sensory evaluation light 4 grain 2 astringent 1 light 4 grain 2 light 4 S-like odor 3 grain 2 astringent 1

INDUSTRIAL APPLICABILITY

[0057]

By using the production method for a fermented malt beverage according to the present invention, a fermented malt beverage having a markedly reduced sugar content can be produced even when the proportion of malt used in the fermentation raw materials is high. This production method and the fermented malt beverage produced using the production method can be utilized in the field of production of beer-tasting beverages that use a malt as a raw material, including beer.

Claims

1. A production method for a fermented malt beverage, wherein a malt in an amount of 65 to 100% by mass of a fermentation raw material is used as a raw material, a glucoamylase is added during at least one of a charging step and a fermentation step, and a transglucosidase is added in the fermentation step, thereby reducing an apparent extract of the beverage to -0.60% by mass or less.

2. The production method for a fermented malt beverage according to Claim 1, wherein the transglucosidase is added in an amount of at least 3 U/g relative to an extract concentration.

3. The production method for a fermented malt beverage according to Claim 1 or 2, wherein the fermentation step is performed at 5 to 15°C.

4. The production method for a fermented malt beverage according to any one of Claims 1 to 3, wherein an amount of malt used is from 65 to 100% by mass of a fermentation raw material.

5. The production method for a fermented malt beverage according to any one of Claims 1 to 4, wherein a sugar content in the fermented malt beverage is less than 0.5 g/100 mL.

6. A fermented malt beverage, in which an amount of malt used is from 65 to 100% by mass of a fermentation raw material, in which a sugar content is less than 0.5 g/100 mL, and an apparent extract is -0.60% by mass or less.

7. The production method for a fermented malt beverage according to any one of Claims 1 to 5, wherein the glucoamylase is added during a charging step and a fermentation step.