Beer concentrate

Abstract

The present invention relates to a beer concentrate having an ethanol content of at least 10% by weight and containing n-octanoic acid at a concentration of 0 to 20 micrograms per gram of ethanol. The present invention further relates to a method for preparing the aforementioned beer concentrate, comprising the steps of: preparing an alcohol-containing beer having an alcohol content of 2 to 12% ABV; contacting the beer with a ZSM-5 zeolite having a molar ratio of at least 1,000 SiO2 / Al2O3; separating the beer from the ZSM-5 zeolite; and removing water from the zeolite-treated beer by membrane filtration and / or freeze concentration. By selectively removing n-octanoic acid, a high-quality beer concentrate with excellent flavor stability can be obtained.

Description

[Technical Field]

[0001] The present invention relates to beer concentrate, more specifically to beer concentrate with improved flavor stability. The present invention also provides a method for preparing such beer concentrate, which includes contacting alcohol-containing beer with zeolite before concentrating the beer. [Background technology]

[0002] Home appliances for preparing and supplying carbonated beverages from concentrated syrups, such as Sodastream®, are rapidly gaining popularity. These appliances produce carbonated beverages by carbonating water and mixing the carbonated water with flavored syrups. Given the high degree of flexibility and convenience offered by these appliances, it would be desirable to have access to beer concentrate, which can be used to produce beer using similar equipment.

[0003] Beer typically contains over 90% water, so removing most of the water can significantly concentrate it. The advantages of producing beer from concentrate are recognized in the field. However, producing a beer concentrate that is suitable for use in producing high-quality beer remains a challenging task.

[0004] Firstly, water must be selectively removed to avoid the loss of beer components that contribute to flavor substances, color, and / or foam formation and stability. Removing water from beer promotes chemical reactions between reactive beer components, leading to undesirable changes in flavor (flavor destabilization). Therefore, measures must be taken to suppress chemical reactions that cause such changes in flavor, such as the reaction between fatty acids and ethanol.

[0005] n-octanoic acid (caprylic acid) is the most abundant free fatty acid in beer. n-octanoic acid is formed during yeast fermentation and is typically present in beer at concentrations of 2.6–7 mg / L (Clapperton, Fatty Acids Contributing to Caprylic Flavour in Beer, the Use of Profile and Threshold Data in Flavour Research, J.Inst.Brew. (1978), vol.84, 107–112).

[0006] Volatile esters constitute a significant group of aromatic compounds in beer. Although volatile esters are only trace compounds in fermented beverages like beer, they are crucial to the flavor profile. The most important flavor-active esters in beer are ethyl acetate (solvent-like aroma), isoamyl acetate (fruity, banana aroma), ethyl hexanoate and ethyl octanoate (sour apple), and phenylethyl acetate (floral, rose, honey). However, the presence of different esters can have synergistic effects on individual flavors. This means that esters can influence the flavor of beer even at concentrations well below their individual threshold concentrations. Furthermore, the fact that most esters exist near their threshold concentrations suggests that even slight changes in concentration can dramatically affect the flavor of beer (HIralal et al., Stability profile of flavor-active ester compounds in pale and lager beer during storage, African Journal of Biotechnology (2013), Vol.12(5), 491-498).

[0007] ZSM-5 is an aluminosilicate zeolite belonging to the pentasil-type zeolite group, and its chemical formula is Na n Al n Si 96-n O 192·16H2O (0<n<27). ZSM-5 is composed of a plurality of pentasil units integrally connected by oxygen bridges, forming pentasil chains. A pentasil unit consists of eight 5-membered rings. In these rings, the vertices are Al or Si, and O is considered to be bonded between the vertices. The pentasil chains are interconnected by oxygen bridges to form a corrugated sheet with 10-membered ring pores. Similar to the pentasil unit, each 10-membered ring pore has Al or Si as vertices, and O is considered to be bonded between each vertex. Each corrugated sheet is connected by oxygen bridges to form a structure with linear 10-membered ring channels running parallel to the wavy structure and zigzag 10-membered ring channels perpendicular to the sheet. Adjacent layers of the sheet are related by inversion points. The estimated pore diameter of the channels running parallel to the wavy structure is 5.4 to 5.6 Å. The crystallographic unit cell of ZSM-5 has 96 T sites (Si or Al), 192 O sites, and a plurality of compensating cations corresponding to the Si / Al ratio (ranging from 12 to infinity).

[0008] WO 2007 / 061602 pamphlet describes a method for removing 2,4,6-trichloroanisole from a beverage, which comprises bringing the beverage into contact with a molecular sieve which is a Y-type zeolite (faujasite) having a Si / Al ratio of at least 5.

[0009] WO 2018 / 213154 pamphlet describes a method for adjusting the flavor profile of food, which comprises treating the food in the presence of one or more molecular sieves that remove all or part of one or more flavor compounds and one or more toxic compounds.

[0010] WO 2020 / 055233 pamphlet describes a method for producing non-alcoholic beer, which comprises bringing non-alcoholic beer into contact with a hydrophobic silicate-based molecular sieve comprising SiO2 and Al2O3 in a molar ratio of at least 15.

[0011] U.S. Patent Application Publication No. 2023 / 083666 describes a single-use capsule for preparing a beer-like beverage, the capsule comprising at least two compartments, The first compartment contains an aqueous liquid having an ethanol content of 0-10% ABV and 0.1-25% by weight of protein. The second compartment contains an alcohol-containing liquid comprising 20-99.9% by weight of ethanol, 0-60% by weight of water, and 50-2,000 mg / kg of hop acid, with the ethanol and water together constituting at least 80% by weight of the alcohol-containing liquid. [Overview of the project] [Means for solving the problem]

[0012] The inventors have developed a beer concentrate that possesses both excellent flavor quality and high flavor stability. The inventors discovered that the formation of ethyl octanoate is a key factor in the flavor instability observed in beer concentrates. This ester formation is accompanied by the development of fruity flavor notes, particularly those reminiscent of pineapple and apricot.

[0013] The beer concentrate of the present invention is prepared by a method that selectively removes n-octanoic acid (caprylic acid) during the preparation of the beer concentrate. By selectively removing this ethyl octanoate precursor, a high-quality beer concentrate with excellent flavor stability can be obtained.

[0014] Accordingly, a first aspect of the present invention relates to a beer concentrate having an ethanol content of at least 10% by weight and containing n-octanoic acid at a concentration of 0 to 20 micrograms per gram of ethanol. Since the rate of ethyloctanoic acid production in the beer concentrate largely depends on the ethanol content of the beer concentrate, the effect of the present invention is most accurately defined based on the reduction in the n-octanoic acid:ethanol ratio achieved.

[0015] Another aspect of the present invention relates to the method for preparing the beer concentrate described above. This method is The process of preparing alcoholic beer with an alcohol content of 2-12% ABV; • A step of contacting beer with ZSM-5 zeolite having a molar ratio of at least 1,000 SiO2 / Al2O3; • The process of separating beer from ZSM-5 zeolite; and • A process of removing water from beer treated with zeolite by membrane filtration and / or freeze-concentration. It contains consecutive occurrences.

[0016] While the inventors do not wish to be bound by theory, they believe that the pore size and the ability of ZSM-5 zeolite to bind to nonpolar compounds contribute to the selective removal of octanoic acid. [Modes for carrying out the invention]

[0017] A first aspect of the present invention relates to a beer concentrate obtained by removing water from beer by nanofiltration, reverse osmosis, forward osmosis, and / or freeze concentration, wherein the concentrate has an ethanol content of at least 10% by weight and contains n-octanoic acid at a concentration of 0 to 20 micrograms per gram of ethanol.

[0018] As used herein, the term “beer” refers to a yeast-fermented malt beverage to which hops may be optionally added. Beer is generally produced by a process that includes the following basic steps: The process of mashing a mixture containing malted barley, optional auxiliary grains, and water to produce a mash; • The process of separating the mash into wort and spent grain; • The process of boiling the wort to produce boiled wort; • The process of fermenting boiled wort with live yeast to produce fermented wort; The process of producing beer by performing one or more additional processing steps (e.g., maturation and filtration) on fermented wort; and ·A step of filling beer into a sealed container (e.g., a bottle, can, or keg).

[0019] Hops or hop extracts are usually added during wort boiling to impart bitterness and floral, fruity flavor notes to the final beer.

[0020] As used herein, the term "lager beer" refers to beer that has been brewed and matured at a temperature below 15°C. The yeast used in the production of lager beer is called bottom-fermenting yeast because it settles at the bottom of the beer during fermentation.

[0021] As used herein, the term "beer concentrate" refers to beer from which water has been removed by, for example, nanofiltration, reverse osmosis, forward osmosis, and / or freeze concentration.

[0022] As used herein, the term "membrane separation" refers to a separation method for separating molecules by passing a feed stream through a membrane that separates the feed stream into two separate streams called permeate and retentate. Examples of membrane separation include nanofiltration, reverse osmosis, and forward osmosis.

[0023] As used herein, the term "free amino nitrogen" refers to the total concentration of individual amino acids and low-molecular-weight peptides, as determined by EBC method 9.10.1-Free Amino Nitrogen in Beer by Spectrophotometry (IM).

[0024] Unless otherwise indicated, the concentrations of acids referred to herein include not only dissolved salts of these acids, but also dissociated forms of these same acids and salts.

[0025] As used herein, the term "iso-alpha acid" refers to a substance selected from the group of isohumulones, isoadhumulones, isocohumulones, preisohumulones, postisohumulones, and combinations thereof. The term "iso-alpha acid" includes different stereoisomers (cis-iso-alpha acids and trans-iso-alpha acids). Iso-alpha acids are typically produced in beer by the addition of hops to boiling wort. They may also be introduced into beer in the form of hop extract before isomerization.

[0026] The beer concentrate of the present invention is preferably a lager beer concentrate.

[0027] In a more preferred embodiment, the beer is 100% malt beer.

[0028] The beer concentrate of the present invention preferably has an ethanol content in the range of 15 to 70% by weight, more preferably 18 to 60% by weight, and most preferably 20 to 55% by weight.

[0029] The amount of n-octanoic acid in the beer concentrate is preferably 0.3 to 15 micrograms per gram of ethanol, more preferably 0.5 to 12 micrograms per gram of ethanol, and most preferably 1.0 to 10 micrograms per gram of ethanol.

[0030] The beer concentrate of the present invention preferably contains n-hexanoic acid at a concentration of 0 to 30 micrograms per gram of ethanol, more preferably 1.0 to 20 micrograms per gram of ethanol, and most preferably 3.0 to 15 micrograms per gram of ethanol.

[0031] n-hexanoic acid and n-octanoic acid are preferably present in the beer concentrate in a weight ratio of n-hexanoic acid:n-octanoic acid of at least 1.0, more preferably 1.1 to 40, and most preferably 1.2 to 5.0.

[0032] The beer concentrate preferably contains n-hexanoic acid and n-octanoic acid at a total concentration of 0 to 40 micrograms per gram of ethanol, more preferably 2 to 30 micrograms per gram of ethanol, and most preferably 4 to 25 micrograms per gram of ethanol.

[0033] The beer concentrate preferably contains 3-methylbutanoic acid (isovaleric acid) at a concentration of 5 to 100 micrograms per gram of ethanol, more preferably 10 to 90 micrograms per gram of ethanol, and most preferably 20 to 80 micrograms per gram of ethanol.

[0034] In a preferred embodiment, 3-methylbutanoic acid and n-octanoic acid are present in the beer concentrate in a weight ratio of at least 1, more preferably 2 to 100, and most preferably 3 to 30 for 3-methylbutanoic acid:n-octanoic acid.

[0035] Ethyl octanoate is preferably included in the beer concentrate at a concentration of 0 to 10 micrograms per gram of ethanol, more preferably 0.02 to 4 micrograms per gram of ethanol, and most preferably 0.05 to 2 micrograms per gram of ethanol.

[0036] The beer concentrate preferably contains ethyl hexanoate at a concentration of 0 to 10 micrograms per gram of ethanol, more preferably 0.1 to 10 micrograms per gram of ethanol, and most preferably 0.3 to 8 micrograms per gram of ethanol.

[0037] The beer concentrate of the present invention preferably contains iso-alpha acids at a total concentration of 50 to 2,400 micrograms per gram of ethanol, more preferably 100 to 2,000 micrograms per gram of ethanol, and most preferably 200 to 1,500 micrograms per gram of ethanol.

[0038] Amyl alcohols (chemical formula C5H) 11The alcohols (OH) are preferably included in the beer concentrate at a total concentration of 50 to 10,000 micrograms per gram of ethanol, more preferably at a total concentration of 100 to 5,000 micrograms per gram of ethanol, and most preferably at a total concentration of 150 to 1,000 micrograms per gram of ethanol.

[0039] Isobutanol is preferably contained in the beer concentrate at a concentration of 0.1 to 4 milligrams per gram of ethanol, more preferably 0.2 to 2 milligrams per gram of ethanol, and most preferably 0.3 to 1 milligram per gram of ethanol.

[0040] Riboflavin, free fatty acids (e.g., linoleic acid), amino acids, and low molecular weight peptides are naturally occurring substances in malted barley and are usually present in high concentrations in beer. Similarly, maltotetraose is also found in high concentrations in beer. This is because this oligosaccharide is produced by enzymatic hydrolysis of starch during mashing and is not digested by yeast. The beer concentrate of the present invention is preferably obtained from beer using a concentration method that removes only water, or only water and low molecular weight substances and ions. As a result, the beer concentrate usually contains considerable amounts of riboflavin, linoleic acid, amino acids, peptides, and / or maltotetraose.

[0041] The riboflavin content in the beer concentrate is preferably in the range of 1.0 to 12 micrograms per gram of ethanol, more preferably 1.2 to 10 micrograms per gram of ethanol, more preferably 1.4 to 8.8 micrograms per gram of ethanol, and most preferably 1.6 to 8.0 micrograms per gram of ethanol.

[0042] The beer concentrate preferably contains 0.6 to 20 micrograms of linoleic acid per gram of ethanol, more preferably 0.8 to 16 micrograms of linoleic acid per gram of ethanol, even more preferably 1 to 14 micrograms of linoleic acid per gram of ethanol, and most preferably 1.2 to 9 micrograms of linoleic acid per gram of ethanol.

[0043] In addition to linoleic acid, beer concentrate typically also contains other unsaturated fatty acids such as oleic acid and / or alpha-linolenic acid. Oleic acid is preferably present in the beer concentrate at a concentration of 1.2 to 12 micrograms per gram of ethanol, more preferably 1.6 to 10 micrograms per gram of ethanol, even more preferably 2.0 to 8.0 micrograms per gram of ethanol, and most preferably 2.4 to 7.2 micrograms per gram of ethanol.

[0044] Alpha-linolenic acid is preferably present in the beer concentrate at a concentration of 0.4 to 4.8 micrograms per gram of ethanol, more preferably 0.5 to 4.4 micrograms per gram of ethanol, even more preferably 0.6 to 4.0 micrograms per gram of ethanol, and most preferably 0.7, 3, or 6 micrograms per gram of ethanol.

[0045] The beer concentrate preferably contains free amino nitrogen (FAN) at a concentration of 0.5 to 8 milligrams per gram of ethanol, more preferably 1 to 6 milligrams per gram of ethanol, and most preferably 1.5 to 4.0 milligrams per gram of ethanol.

[0046] The beer concentrate contains carbohydrates at a concentration of 0.1 to 2 grams per gram of ethanol. More preferably, the beer contains carbohydrates at a concentration of 0.2 to 1 gram per gram of ethanol.

[0047] Unlike maltose and maltotriose, which are maltose, maltotetraose is hardly broken down by most brewer's yeasts. Therefore, the concentration of maltotetraose is usually hardly affected by yeast fermentation. Accordingly, the beer concentrate preferably contains 20 to 400 micrograms of maltotetraose per gram of ethanol, more preferably 40 to 300 micrograms of maltotetraose per gram of ethanol, even more preferably 50 to 250 micrograms of maltotetraose per gram of ethanol, and most preferably 60 to 200 micrograms of maltotetraose per gram of ethanol.

[0048] Preferably, the beer concentrate contains 0.4 to 5 milligrams of acetic acid per gram of ethanol, more preferably 0.5 to 4 milligrams of acetic acid per gram of ethanol, even more preferably 0.6 to 3.6 milligrams of acetic acid per gram of ethanol, and most preferably 0.7 to 3.2 milligrams of acetic acid per gram of ethanol.

[0049] Another aspect of the present invention is a method for preparing beer concentrate according to the present invention, The process of preparing alcoholic beer with an alcohol content of 2-12% ABV; • A step of contacting beer with ZSM-5 zeolite having a molar ratio of at least 1,000 SiO2 / Al2O3; • The process of separating beer from ZSM-5 zeolite; and • A process of removing water from beer treated with zeolite by membrane filtration and / or freeze-concentration. Regarding methods for including consecutive elements.

[0050] In a particularly preferred embodiment, the alcohol-containing beer used in this method is an alcohol-containing lager beer.

[0051] According to another preferred embodiment, the alcohol-containing beer is a 100% malt alcohol-containing beer.

[0052] Preferably, the alcohol-containing beer used in this method has an alcohol content of 3-10% ABV, more preferably 4-8% ABV.

[0053] Preferably, the alcohol-containing beer has a temperature in the range of 0 to 25°C, more preferably in the range of 4 to 20°C, when in contact with the ZSM-5 zeolite.

[0054] The alcohol-containing beer is preferably in contact with the zeolite for at least 10 minutes, more preferably 15 to 400 minutes, and most preferably 20 to 200 minutes.

[0055] Contact between the alcohol-containing beer and the zeolite is preferably carried out at a pressure of 0.5 to 2 bar, more preferably 0.8 to 1.2 bar.

[0056] Preferably, the alcohol-containing beer is brought into contact with the ZSM-5 zeolite by mixing 1,000,000 parts by weight of alcohol-containing beer with at least 10 parts by weight of ZSM-5 zeolite. More preferably, the alcohol-containing beer is brought into contact with the ZSM-5 zeolite by mixing 1,000,000 parts by weight of alcohol-containing beer with 100 to 1,000 parts by weight of ZSM-5 zeolite.

[0057] Alcohol-containing beer can be brought into contact with zeolite by mixing it with the beer. Alternatively, the beer may be passed through a floor made of zeolite particles.

[0058] When alcohol-containing beer is brought into contact with zeolite by mixing it with beer, the beer treated with zeolite can be separated after contact by performing solid-liquid separation methods known in the art, such as decantation, centrifugation, and filtration.

[0059] Preferably, the ZSM-5 zeolite is used in the form of a powder. The ZSM-5 zeolite preferably has a D in the range of 0.5 to 10 micrometers, more preferably in the range of 1 to 6 micrometers, and most preferably in the range of 2 to 5 micrometers 50 . The particle size distribution of the zeolite powder can be determined by laser diffraction.

[0060] The surface area of the ZSM-5 zeolite is preferably at least 100 m 2 / g, more preferably 150 to 2,000 m 2 / g, and most preferably 200 to 1,000 m 2 / g. The surface area of the hydrophobic molecular sieve can be determined by the BET method.

[0061] The ZSM-5 zeolite used in the present method preferably has a SiO2 / Al2O3 molar ratio of greater than 2,000.

[0062] Water can be suitably removed from the zeolite-treated beer by performing freeze concentration. In this method, water is removed from the beer by a phase transition from liquid to ice crystals. This process mainly has three stages: water crystallization, water crystal growth, and water crystal separation, which are carried out in specially designed apparatuses for each purpose (for example, a scraper-type heat exchanger, a growth recrystallizer, and a separation and washing tower respectively). Basically, the temperature of the non-alcoholic beer is lowered to a value at which at least part of the water freezes without reaching the eutectic point of the mixture. When the ice crystals are sufficiently large (for example, 100 μm or more in diameter), the crystals can be separated from the concentrated liquid, for example by using a washing tower. Due to the low treatment temperature below 0°C, flavor loss due to thermal degradation and evaporation is avoided.

[0063] Water can also be removed from zeolite-treated beer by membrane separation using a membrane having a magnesium sulfate rejection rate of 80-100%, more preferably 90-100%, and most preferably 95-100% (measured at 0.48 MPa, 25°C, and a recovery rate of 15% using a 2,000 mg / L aqueous magnesium sulfate solution).

[0064] In a particularly preferred embodiment, water is removed from the zeolite-treated beer by reverse osmosis or forward osmosis using a membrane having a sodium chloride rejection rate of 80-100%, more preferably 90-100%, and most preferably 95-100% (measured at 10.3 bar, 25°C, pH 8, and a recovery rate of 15% using a 2,000 mg / L aqueous sodium chloride solution).

[0065] The present invention can be further described by the following non-limiting embodiments. [Examples]

[0066] Example 1 Lager beer (7% ABW) was brought into contact with ZSM-5 zeolite as follows: The beer was chilled to 4°C; Zeolite was added at a concentration of 0.25 g / L; The mixture of beer and zeolite was held in a stirring vessel at 4°C for 45 hours; • Zeolite was removed from the beer by filtration.

[0067] The ZSM zeolite used had the following characteristics: - MFI Zeolite - Molar ratio SiO2 / Al2O3 ≥ 1,000 - BET surface area: approx. 350m 2 / g - Pore size: 5.6 Å (straight), 5.3 Å (sinusoidal)

[0068] Example 2 Both the original lager beer from Example 1 (reference) and the beer treated with zeolite (Beer 1) were concentrated by freeze concentration.

[0069] The resulting beer concentrate was stored at 4°C for 3 weeks, and then at 30°C for 3 months (a total of 15 weeks). At the beginning and end of the storage period, the beer concentrate was diluted with water to achieve an ethanol content of 5% ABV and analyzed. The analysis results are shown in Table 1.

[0070] [Table 1]

Claims

1. A beer concentrate obtained by removing water from beer by nanofiltration, reverse osmosis, forward osmosis, and / or freeze concentration, having an ethanol content of at least 10% by weight and containing n-octanoic acid at a concentration of 0 to 20 micrograms per gram of ethanol.

2. The beer concentrate according to claim 1, containing n-hexanoic acid at a concentration of 0 to 30 micrograms per gram of ethanol.

3. The beer concentrate according to claim 2, wherein n-hexanoic acid and n-octanoic acid are present in a weight ratio of at least 1.0, more preferably 1.2 to 40, of n-hexanoic acid:n-octanoic acid.

4. A beer concentrate according to any one of claims 1 to 3, containing 3-methylbutanoic acid at a concentration of 5 to 100 micrograms per gram of ethanol.

5. The beer concentrate according to claim 4, wherein 3-methylbutanoic acid and n-octanoic acid are present in a weight ratio of at least 1, preferably 2 to 100, of 3-methylbutanoic acid:n-octanoic acid.

6. A beer concentrate according to any one of claims 1 to 5, containing ethyl octanoate at a concentration of 0 to 10 micrograms per gram of ethanol.

7. A beer concentrate according to any one of claims 1 to 6, containing ethyl hexanoate at a concentration of 0 to 10 micrograms per gram of ethanol.

8. The beer concentrate according to any one of claims 1 to 7, containing n-hexanoic acid and n-octanoic acid at a total concentration of 0 to 40 micrograms per gram of ethanol.

9. A beer concentrate according to any one of claims 1 to 8, containing iso-alpha acids at a total concentration of 50 to 2,400 micrograms per gram of ethanol.

10. A beer concentrate according to any one of claims 1 to 9, containing amyl alcohols at a total concentration of 50 to 10,000 micrograms per gram of ethanol.

11. A beer concentrate according to any one of claims 1 to 10, containing isobutanol at a concentration of 0.1 to 4 milligrams per gram of ethanol.

12. A beer concentrate according to any one of claims 1 to 11, containing free amino nitrogen (FAN) at a concentration of 0.5 to 8 milligrams per gram of ethanol.

13. A beer concentrate according to any one of claims 1 to 12, containing carbohydrates at a concentration of 0.1 to 2 grams per gram of ethanol.

14. A method for preparing a beer concentrate according to any one of claims 1 to 13, - The process of preparing alcoholic beer with an alcohol content of 2-12% ABV; • Molar ratio of SiO₂ at least 1,000 ２ / Al ２ O ３ A step of bringing ZSM-5 zeolite having the above-mentioned beer into contact with the beer; - A step of separating the beer from the ZSM-5 zeolite; and - A step of removing water from the beer treated with the zeolite by membrane filtration and / or freeze concentration. A method that includes consecutive elements.

15. The method according to claim 14, wherein the alcohol-containing beer is brought into contact with the ZSM-5 zeolite by mixing 100 parts by weight of alcohol-containing beer with at least 1 part by weight of ZSM-5 zeolite.

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