Beer with high wheat fragrance and brewing method thereof

Abstract

The invention provides beer with high wheat fragrance and a brewing method thereof, and belongs to the technical field of wine brewing. According to the high-wheat-fragrance beer provided by the invention, malt in a beer raw material formula consists of 100% of high-wheat-fragrance malt in percentage by mass, the proportion of fragrant amino acid in the high-wheat-fragrance malt is greater than 40%, and the content of proline accounts for 20% or above. According to the beer, based on selection of high-wheat-aroma malt varieties and appropriate malt solubility control, the wheat aroma flavor is precisely regulated and controlled, so that the content of wheat aroma flavor substances in the high-wheat-aroma beer is effectively increased, the malt aroma is pure and rich, the taste is soft and coordinated, and the typical malt aroma flavor characteristics of common Lager beer are highlighted.

Description

Technical Field

[0001] The invention belongs to the technical field of wine brewing, and in particular relates to a high-malt aroma beer and a brewing method thereof. Background Art

[0002] Beer is an alcoholic beverage containing carbon dioxide, made from water, malt and hops as the main ingredients, fermented by yeast. Malt aroma is one of the scoring items for the sensory characteristics of beer in the professional qualification examination for sommeliers of the China Liquor Association, and is also the most intuitive evaluation indicator for consumers. As consumers' appreciation of beer improves, the malt aroma flavor, which reflects the individual differences of beer, has received more and more attention from researchers and brewers.

[0003] However, due to the complexity of the beer brewing process and the diversity of products, the definition, identification and regulation of beer malt aroma is still a vague concept in the industry, lacking systematic research, especially the evaluation of beer malt aroma, which often relies on sensory organs and lacks understanding of the material basis of malt aroma. It is generally believed that malt flavor is the flavor produced by proteins, amino acids and sugars through a series of processes such as malting (especially malt roasting stage), saccharification and fermentation, through Maillard reaction, caramelization reaction, Strecker degradation, yeast metabolism, etc. These substances provide beer with a special aroma.

[0004] The Maillard reaction is considered to be the main way to produce malt aroma substances and the basis of related flavors. The aroma in malt has a significant impact on the quality of beer. The Maillard reaction in the malting drying and roasting process is the main way to produce malt flavor and color. So far, more than 250 flavor substances have been detected in malt. These flavor substances will bring special malt aroma to beer (such as caramel, nutty, roasted, etc.). However, during the brewing process, especially in high-temperature processes such as wort boiling and vortex precipitation, the Maillard reaction can continue to generate complex flavors.

[0005] According to literature reports and combined with tasting, furanones and pyrazine compounds in the Maillard reaction products of beer brewing process were determined to be the key substances for producing malt aroma from hundreds of substances. Pyrazine compounds refer to nitrogen-containing six-membered heterocyclic components, mainly including 2-methylpyrazine, 2,5-dimethylpyrazine, 2,6-dimethylpyrazine, 2-ethylpyrazine, 2,3-dimethylpyrazine, 2-ethyl-6-methylpyrazine, 2-acetylpyrrole (2-AP) and other substances, which can give beer a special roasted flavor. Furanone compounds are a class of oxygen-containing five-membered heterocyclic compounds, mainly including maltol, 2,5-dimethyl-4-hydroxy-3(2H)-furanone (DMHF), 2-acetylfuran, 5-methylfurfural, etc., with typical sweetness, caramel and caramel flavors. There are many flavor substances that contribute to malt aroma in beer, with DMHF and 2-AP as typical indicator substances.

[0006] Considering the complexity of the Maillard reaction, most studies use a simple model system consisting of a single amino acid or a mixture of a few amino acids and reducing sugars. However, how to qualitatively identify and preliminarily analyze its volatile reaction products in order to deepen the understanding of the Maillard reaction in the wort boiling process and guide production practice still needs further research. Summary of the invention

[0007] The present invention provides a high-malt aroma beer and a brewing method thereof. The beer has a high-malt aroma flavor, which is precisely regulated based on the selection of high-malt aroma malt varieties and appropriate malt solubility control, so that the content of malt aroma flavor substances in the high-malt aroma beer is effectively improved, the malt aroma is pure and rich, the taste is soft and coordinated, and the typical malt aroma and flavor characteristics of ordinary Lager beer are highlighted.

[0008] In order to achieve the above-mentioned object, the present invention provides a high-malt aroma beer. Calculated by mass percentage, the malt in the beer raw material formula is composed of 100% high-malt aroma malt, the proportion of aromatic amino acids in the high-malt aroma malt is greater than 40%, and the content of proline accounts for more than 20%.

[0009] Preferably, the solubility aN of the high malt aroma malt is between 140-160 mg / 100 g.

[0010] Preferably, the aromatic amino acids consist of arginine, proline, lysine and histidine.

[0011] Preferably, the high malt aroma malt is selected from at least one of Canadian malts Copeland, Metcalfe, Kendall, Synergy, Harrington and Australian malts Gairdner, Baudin, Bass, Spartacus. It is understood that there is no specific requirement for the selection of specific varieties of Canadian malt and Australian malt, as long as they are Canadian malt and Australian malt varieties within the range familiar to those skilled in the art.

[0012] Preferably, the malt raw material consists of 100% Canadian malt, or 100% Australian malt, or 100% Canadian malt and Australian malt in any proportion.

[0013] Preferably, the beer raw material formula also includes rice as an auxiliary material.

[0014] Preferably, the original wort concentration of the beer is 10°P, the chroma is 5-8EBC, the RDF is between 65-68%, the alcohol-ester ratio is 4.5-5.5, and the malt aroma substance 2-AP content in the beer is ≥45μg / L, and the DMHF content is ≥1.5mg / L.

[0015] The present invention also provides a method for brewing high malt aroma beer according to any one of the above technical solutions, comprising the following steps:

[0016] The rice is crushed and then transferred into a gelatinization pot, and an appropriate amount of thermostable α-amylase is added. After hydrolysis at 90°C for 10-15 minutes, the temperature is raised to 100°C and kept warm for 15-20 minutes to prepare a rice gelatinization mash;

[0017] Grind the malt and transfer it to the mash, put it into the saccharification pot, adjust the pH value of the mash to 5.6-5.8, and perform protein rest at 50℃. After the protein rest, add the gelatinized mash and raise the temperature to 63-66℃. Saccharify for 40-60 minutes, stirring and mixing evenly during the process.

[0018] The wort is then filtered and boiled. After the boiling, the wort is vortexed and precipitated to control the wort concentration at 13°P.

[0019] After the wort is boiled, the mash is transferred to a whirlpool settling tank for full rest, cooled to 7.5-8.5°C through a thin plate heat exchanger, and sterile compressed air is introduced to make the dissolved oxygen content of the cold wort reach 10-12 mg / L;

[0020] The oxygenated wort is pumped into the fermentation tank, and the yeast count in the tank is controlled at 20-23MM / mL. The temperature is naturally raised to 9.5-10.0℃ for main fermentation, and the sugar content of the fermentation liquid is tested every 12 hours. When the sugar content of the fermentation liquid drops to 3.5°P, the temperature is raised to the reduction temperature of 12±0.5℃. When the diacetyl drops to 0.03mg / L, the reduction of the beer is completed and the temperature is further lowered for cold storage to obtain high malt aroma beer.

[0021] Preferably, the boiling time is 60-90 min, the boiling evaporation rate is 6-10%, and the boiling pH is controlled to be 5.4-5.6.

[0022] Preferably, hops or hop products are added three times in an amount of 0.05% by weight of the wort during the boiling process, the hops or hop products are selected from any one of Qingdao Dahua, Tietnan hops, HHT hops, and Nugget hops, wherein the third hop addition is aroma hops, the aroma hops are selected from any one of Cascade, Saaz, Zhayi Xianghua, and Xinyuan Xianghua, and the addition time is 10 minutes after the end of the current boiling.

[0023] Compared with the prior art, the advantages and positive effects of the present invention are:

[0024] 1. The present invention provides a beer brewing technology based on the regulation of four kinds of aromatic amino acids, including the selection of high malt aroma malt varieties and the appropriate control of malt solubility, which makes the regulation of malt aroma more precise and reduces the blindness of process control.

[0025] 2. The content of 2-AP and DMHF, the malt flavor substances in the high malt aroma beer provided by the present invention, is increased by more than 50%. The brewed beer is evaluated by national tasters for its sensory properties and has a significant malt aroma. The malt aroma is pure and rich, and the taste is soft and coordinated, highlighting the typical malt aroma and flavor characteristics of ordinary Lager beer, thereby enhancing the core competitiveness of the product. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 Cluster analysis of the differences in amino acid composition between malt varieties provided in the embodiments of the present invention. DETAILED DESCRIPTION

[0027] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0028] Example 1 Determining the types of aromatic amino acids contributing to malt flavor

[0029] According to the parameters such as temperature and time of the wort preparation process, the Maillard reaction research model was established. By simulating the parameters such as pH, temperature and time in the wort preparation process, a comparative study and preliminary analysis of the color and aroma characteristics of the reactions of 17 amino acids with reducing sugars were conducted in a 0.1 M pH 5.5 buffer solution and heated in a 100°C water bath for 120 min. The taste and aroma of the 17 amino acid reaction solutions were described from the perspective of beer tasting by national beer judges. The results are shown in Table 1.

[0030] Table 1 Aroma characteristics of 17 amino acids and their differences with beer malt flavor

[0031]

[0032]

[0033] Remark:

[0034] Malt flavor similarity: 100 points. Judges score the malt flavor of the samples, and the result is the average of their scores.

[0035] Malt flavor intensity: 10 points, judges score the malt flavor intensity of the evaluation samples, and the result is the average of their scores.

[0036] As can be seen from Table 1, the aroma and flavor characteristics of some amino acid Maillard reaction products are similar, while some are quite different. Among them, His, Arg, Pro, and Lys produce typical malt aromas such as malt, hazelnut, malt biscuit, caramel, and burnt, but the flavors presented are also slightly different. For example, the aroma of His is mainly maltose and sweet, the aroma produced by Arg is more prominent in the burnt flavor, the aroma of Pro is mainly characterized by biscuit aroma and nut aroma, Lys is mainly burnt, which contains butter (diacetyl) and other flavors; Gly produces a pleasant caramel-like aroma; Val's aroma is closer to With the higher alcohols in beer, the mellow taste of bitter almonds; Phe produces the aroma of rose stamens; Ala produces fruity and burnt tastes; Asp and Ser produce pleasant fruity aromas; Ile and Leu produce fermented odors with a slight caramel aroma; Met and Glu will produce a distinct soy sauce flavor, similar to the aging of beer and yeast autolysis, among which Glu can also taste the diacetyl taste of beer; Tyr and Trp have leather, rubber and other odors; Thr has a slight dough flavor with a slight diacetyl taste.

[0037] According to the similarity of beer malt flavor, the aroma amino acids are divided into three categories. The first category is His, Arg, Pro, Lys, which have the highest similarity with beer malt flavor (P < 0.05). The second category is Gly, Val, Ile, Leu, Phe, which have a similarity with malt flavor of less than 80% (P < 0.05). The aroma characteristics of the other 8 amino acids have no intersection with malt flavor. It is determined that the four amino acids Arg, Pro, Lys, and His contribute the most to malt flavor, which we call aroma amino acids, laying the foundation for the amino acid-directed regulation of beer malt flavor.

[0038] Example 2 Cluster analysis of amino acid compositions of different protein sources based on the selection of high malt aroma malt varieties with similar amino acid compositions (e.g. Figure 1 The amino acid composition of malt and the amino acids from soybean, yeast and corn are clearly divided into two categories. The amino acid composition of malt is strongly correlated with barley variety and origin. Further analysis of the amino acid composition ratio of malt of different varieties is shown in Table 2.

[0039] Table 2 Amino acid composition ratio of different varieties of malt

[0040]

[0041] Combined with the data in the above table, we can see that the amino acid composition ratios of the nine malts can be clustered into three categories. The amino acid compositions of Canadian Copeland, Canadian Harrington, and Australian Gairdner malts are similar and are classified into the first category; French Sebastian, French Planet, and French Irina are classified into the second category; the amino acid compositions of other Chinese Gan 14, Chinese Gan-4, and French Etincel are classified into the third category.

[0042] According to the contribution and similarity of 17 kinds of amino acids to the malt flavor, the proportion of four kinds of aromatic amino acids Arg, Pro, Lys, and His in the total amino acids of malt varieties from Canadian, domestic and Australian malt is significantly higher than that of other varieties of barley such as European and French malt, while the proportion of aromatic amino acids in French malt varieties, which are not very strong in malt aroma, is significantly lower. Although the malt aroma of domestic malt is more prominent, there are also many other foreign flavors, such as skin taste, astringency, rough taste, and immature taste, which interfere with the typicality of the malt aroma of domestic malt.

[0043] Combined with the above table, based on the screening principle that the proportion of aromatic amino acids is greater than 40%, among which the Pro content with the highest content and the highest similarity to malt flavor accounts for more than 20%, it is determined to use barley varieties produced in Canada and Australia for brewing high malt aroma beer.

[0044] Example 3 Selection of high malt aroma malt based on the content of aromatic amino acids

[0045] In order to study the relationship between the content of aromatic amino acids and malt aroma, a comparative study of malts with different protein solubility was conducted. In the malting process, aN, inventory value, etc. are generally used as control indicators to measure the degree of solubility of malt protein. During the preparation of barley malt, as the protein decomposes during the germination process, the content of released aromatic amino acids will also change. In order to study the relationship between the content of aromatic amino acids and malt aroma, the following table combines the sensory evaluation of malt and the malt flavor composition in malt (based on the detection of malt varieties and Copeland solid samples of malt) to compare malt aN, total malt amino acids, total amount and proportion of aromatic amino acids, as shown in Table 3.

[0046] Table 3 aN, total malt amino acids, aromatic amino acids and malt aroma index of Copeland malt

[0047]

[0048] Combined with the above table, it can be seen that the total amount of aromatic amino acids (His, Arg, Lys, Pro) increases with the increase of malt aN, and the content of malt aroma substance 2-AP increases. Therefore, by controlling the total amount of aromatic amino acids above 500 mg / L, malt with outstanding malt flavor can be obtained. In addition, the solubility of malt is further improved, the aN of malt is controlled to be higher than 160 mg / 100g, and the proportion of aromatic amino acids in malt is above 40%. The total amount of aromatic amino acids will also increase, but the tasting results have a distinct burnt taste, which is not conducive to beer preparation. Judging from the tasting and the proportion of aromatic amino acids, high malt aroma malt should be screened out with a solubility aN between 140-160 mg / 100g.

[0049] Example 4 Preparation of High Malt Aroma Beer 1

[0050] Raw materials and formula

[0051] 1) Malt selection and matching

[0052] 100% high malt aroma malted malt is used, the malt variety is Copeland malt, and the malt aN is 145mg / L.

[0053] 2) Raw material formula

[0054] The ratio of malt to auxiliary materials is 70:30.

[0055] Wort preparation

[0056] ① Gelatinization: Grind the rice and transfer it into the gelatinization pot. Add an appropriate amount of high-temperature resistant α-amylase. After hydrolysis at 90℃ for 10-15 minutes, heat it to 100℃ and keep it warm for 15 minutes to prepare the rice gelatinization mash. Under the combined action of heat and amylase, the starch of rice is decomposed into soluble oligosaccharides and dextrin, laying the foundation for obtaining a large amount of fermentable sugar and increasing the sugar extract in the saccharification process.

[0057] ②Saccharification: Grind the malt and transfer it to the saccharification pot. Adjust the pH value of the mash to 5.6-5.8, and perform protein rest at 50℃. After the protein rest, add the gelatinized mash and heat it to 63-66℃. Saccharify for 40-60 minutes, stirring and mixing evenly during the process. The stirrer of the saccharification pot is used throughout the saccharification process, and the stirring rate is 7rpm / min. Then filter the wort and boil it after filtering.

[0058] ③ Boiling: During the wort boiling process, the boiling time is controlled to be 60-90min, the boiling evaporation rate is 6-10%, and the boiling pH is controlled to be 5.4-5.6. This process is conducive to the Maillard reaction of the wort, generates more malt aroma substances, and more effectively removes undesirable flavors such as foreign tastes; during the boiling process, 0.05% of hops or hop products by weight of the wort, such as Qingdao Dahua and Cascade hops, are added three times, wherein the third hop addition is flavor hops, including Cascade, Saaz, Zhayixianghua, etc., and the addition time is completed when the boiling is completed; after the boiling is completed, the wort concentration is controlled to be 13°P after vortex precipitation.

[0059] ④ Whirlpool sedimentation and wort cooling: After the wort is boiled, the mash is transferred into the whirlpool sedimentation tank and allowed to rest for 20 minutes. It is cooled to 7.5-8.5℃ through thin plate heat exchange, and sterile compressed air is introduced to make the dissolved oxygen content of the cold wort reach 10-12mg / L.

[0060] Beer fermentation

[0061] The oxygenated wort is pumped into the fermentation tank, and the yeast count in the tank is controlled at 20-23MM / mL. The temperature is naturally raised to 9.5-10.0℃ for main fermentation. The sugar content of the fermentation liquid is tested every 12 hours. When the sugar content of the fermentation liquid drops to 3.5°P, the temperature is raised to the reduction temperature of 12±0.5℃. When the diacetyl drops to 0.03mg / L, the wine is reduced and further cooled for cold storage.

[0062] Example 5 Preparation of High Malt Aroma Beer 2

[0063] Raw materials and formula

[0064] 1) Malt selection and matching

[0065] 100% high malt aroma Australian malt is used, the malt variety is Australian malt Gairdner, and the malt aN is 140mg / 100g.

[0066] 2) Raw material formula

[0067] The ratio of malt to auxiliary materials is 70:30.

[0068] The wort preparation and wort fermentation process are the same as in Example 4.

[0069] Example 6 Preparation of High Malt Aroma Beer 3

[0070] Raw materials and formula

[0071] 1) Malt selection and matching

[0072] Use high-malt and aromatic Australian Gairdner malt and Canadian Copeland malt in a 1:1 ratio.

[0073] 2) Raw material formula

[0074] The ratio of malt to auxiliary materials is 70:30.

[0075] The wort preparation and wort fermentation process are the same as in Example 4.

[0076] Comparative Example 1

[0077] Raw material formula

[0078] 1) Malt selection and matching

[0079] High malt aroma Copeland malt is used in combination with ordinary law malt Planet malt, with a ratio of 1:1.

[0080] 2) Raw material formula

[0081] The ratio of malt to auxiliary materials is 70:30.

[0082] The wort preparation and wort fermentation process are the same as in Example 4.

[0083] Comparative Example 2

[0084] Raw material formula

[0085] 1) Malt selection and matching: 100% common method Planet malt is used, and the malt aN is 135 mg / L.

[0086] 2) The ratio of malt to auxiliary materials in the raw material formula is 70:30.

[0087] The wort preparation and wort fermentation process are the same as in Example 4.

[0088] Performance Testing

[0089] Table 4 Comparison of key indicators of malt

[0090]

[0091] Table 5 Comparison of finished beer indicators

[0092]

[0093] Combined with the data in Table 5, it can be seen that the content of malt aroma substances (DMHF, 2-AP substances) in the finished beer products obtained in Examples 4-6 is nearly doubled compared with the content of the components of ordinary beer (Comparative Example 2). In addition, the beer has obvious malt aroma, soft and coordinated taste, full body, and physical and chemical indicators meet the requirements of GB / T 4927 standard after sensory evaluation by national tasters.

Claims

1. A high malt aroma beer, characterized in that: Calculated by mass percentage, the malt in the beer raw material formula is composed of 100% high-malt aroma malt, the proportion of aromatic amino acids in the high-malt aroma malt is greater than 40%, and the content of proline accounts for more than 20%.

2. The high malt aroma beer according to claim 1, characterized in that: The solubility aN of the high malt aroma malt is between 140-160 mg / 100 g.

3. The high malt aroma beer according to claim 1 or 2, characterized in that: The aromatic amino acids consist of arginine, proline, lysine and histidine.

4. The high malt aroma beer according to claim 3, characterized in that: The high malt aroma malt is selected from at least one of Canadian malts such as Copeland, Metcalfe, Kendall, Synergy, Harrington and Australian malts such as Gairdner, Baudin, Bass and Spartacus.

5. The high malt aroma beer according to claim 4, characterized in that: The malt raw material is composed of 100% Canadian malt, or 100% Australian malt, or 100% Canadian malt and Australian malt in any proportion.

6. The high malt aroma beer according to claim 1, characterized in that: The beer raw material formula also includes rice as an auxiliary material, and the auxiliary material accounts for 30% of the total input material.

7. The high malt aroma beer according to any one of claims 1 to 6, characterized in that: The original wort concentration of the beer is 10°P, the chroma is 5-8EBC, the RDF is between 65-68%, the alcohol-ester ratio is 4.5-5.5, and the malt aroma substance 2-AP content in the beer is ≥45μg / L, and the DMHF content is ≥1.5mg / L.

8. The brewing method of high malt aroma beer according to any one of claims 1 to 7, characterized in that: The following steps are involved: The rice is crushed and then transferred into a gelatinization pot, and an appropriate amount of thermostable α-amylase is added. After hydrolysis at 90°C for 10-15 minutes, the temperature is raised to 100°C and kept warm for 15-20 minutes to prepare a rice gelatinization mash; Grind the malt and transfer it to the mash, put it into the saccharification pot, adjust the pH value of the mash to 5.6-5.8, and perform protein rest at 50℃. After the protein rest, add the gelatinized mash and raise the temperature to 63-66℃. Saccharify for 40-60 minutes, stirring and mixing evenly during the process. The wort is then filtered, and after the filtering is completed, it is boiled. After the boiling is completed, the wort is vortexed and precipitated, and the concentration of the final wort is controlled at 13°P; After the wort is boiled, the mash is transferred to a whirlpool settling tank for full rest, cooled to 7.5-8.5°C through a thin plate heat exchanger, and sterile compressed air is introduced to make the dissolved oxygen content of the cold wort reach 10-12 mg / L; The oxygenated wort is pumped into the fermentation tank, and the yeast count in the tank is controlled at 20-23MM / mL. The temperature is naturally raised to 9.5-10.0℃ for main fermentation, and the sugar content of the fermentation liquid is tested every 12 hours. When the sugar content of the fermentation liquid drops to 3.5°P, the temperature is raised to the reduction temperature of 12±0.5℃. When the diacetyl drops to 0.03mg / L, the reduction of the beer is completed and the temperature is further lowered for cold storage to obtain high malt aroma beer.

9. The brewing method according to claim 8, characterized in that: The boiling time is 60-90 minutes, the boiling evaporation rate is 6-10%, and the boiling pH is controlled to be 5.4-5.

6.

10. The brewing method according to claim 8, characterized in that: During the boiling process, 0.05% of hops or hop products by weight of the wort are added three times, the hops or hop products are selected from any one of Qingdao Dahua, Tietnan hops, HHT hops, and Nugget hops, wherein the third hop addition is aroma hops, the aroma hops are selected from any one of Cascade, Saaz, Zhayi Xianghua, and Xinyuan Xianghua, and the addition time is 10 minutes after the end of the current boiling.

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