A sleep-improving pistachio beer and a preparation method thereof

Abstract

The present application belongs to the technical field of beer brewing and food preparation, and provides a spina date beer with improved sleep and a preparation method thereof. A malt extract and spina date pulp malt mixture after malt baking are mixed, water is added, and a gradual warming method is used for saccharification, and a wort is obtained by filtration; a mixed juice of spina date kernels and platycladus orientalis kernels is obtained by using a high hydrostatic pressure treatment process; hops and the mixed juice of spina date kernels and platycladus orientalis kernels are added into the filtered wort for boiling; after inoculation of yeast, low-temperature slow fermentation is carried out, spina date leaves are suspended in the wine, and quality determination is carried out on the mature wine. The present application uses a variety of malt and spina date pulp mixture as the raw material for saccharification, and adds the mixed juice with sleep-aiding effect in the process of wort boiling. The obtained spina date beer has a deep color, a smooth taste, a relatively dense foam, a special spina date flavor, and a coffee-like roasted flavor. The beer contains various nutrients, and has a strong sleep-aiding effect due to the addition of sleep-aiding drugs.

Description

Technical Field

[0001] This invention belongs to the field of beer brewing technology and food preparation, specifically relating to a sour jujube stout beer with sleep-improving effects and its preparation method. Background Technology

[0002] Stout is a type of fermented beer, an improved version of Port beer introduced to Ireland. Unlike pale ales, a distinctive characteristic of stouts is their color. The color is primarily determined by the color of the fermenting agents. Traditional stouts are fermented with dark malts, resulting in a darker color with a color intensity of 40+ EBC. Stouts typically exhibit a brownish-black to deep black hue, giving them a rich and substantial feel. This color signifies high-quality brewing ingredients and sophisticated brewing techniques, while the black appearance also lends a sense of mystery and seriousness. In terms of taste, stouts have a roasted flavor, unlike the bitterness and sharpness of pale ales. They possess the aroma of roasted malt, along with subtle sweetness and bitterness. Visually, stouts have a fine, creamy foam that stays on the surface of the beer in the glass for a relatively long time, with a uniform amount of foam.

[0003] The pulp of jujube is the mature flesh of the jujube tree (Ziziphus jujuba), a plant in the Rhamnaceae family. It is also a significant byproduct of jujube resource utilization. Jujube pulp has effects such as nourishing the liver, calming the mind, stopping bleeding and diarrhea. It also has high nutritional value, containing abundant protein and vitamins. The pulp has a high sugar content, reaching up to 12% after drying. The main sugar components are monosaccharides and a few polysaccharides. Sugars can regulate immunity, have antioxidant activity, scavenge free radicals in the body, and also have anti-tumor and anti-inflammatory effects. After roasting, the pulp becomes more concentrated due to the evaporation of moisture during the roasting process, and pigments from the jujube peel also accumulate.

[0004] The pulp of jujube has the effects of strengthening the spleen and stomach, nourishing the heart and calming the mind, and promoting metabolism. It can be used as a food ingredient in various food categories. At present, there is no research on the components of jujube pulp through jujube pulp roasting technology. There are no products on the market that use jujube pulp and malt roasted together as a saccharification raw material. The improvement of jujube pulp roasting technology can provide a theoretical basis for the expanded utilization of jujube resources.

[0005] Sour jujube seed, a traditional Chinese medicine used in both food and medicine, has the effects of calming the mind, soothing the nerves, astringing sweat, and promoting the production of body fluids. Arborvitae seed, the seed kernel of the arborvitae plant (Platycladus orientalis), has the effects of nourishing the heart, calming the nerves, and moistening the intestines to relieve constipation. Sour jujube seed contains about 30% fatty acids, while arborvitae seed contains about 15%. The fatty acids in both are mainly long-chain unsaturated fatty acids. Unsaturated fatty acids are a type of fatty acid that constitutes body fat and are an important nutrient needed by the human body. They are also an important component of cell membranes, therefore their content and type determine the nutritional and health value of sour jujube seed. The sour jujube seed-arborvitae seed pair contains abundant fatty acids, which contribute to the flavor of stout beer, giving it a richer taste. Some long-chain fatty acids, such as oleic acid and linoleic acid, can increase the fullness and richness of beer, making it smoother and more mellow. Meanwhile, the fatty acid components contained in the medicine can also affect the stability and persistence of beer foaming. An appropriate amount of fatty acids can enhance the stability of the foam, making the foam more persistent and richer. Some specific esterified fatty acids (such as caprylic acid esters) can also provide additional aroma and flavor during the beer foaming process.

[0006] Both jujube seed and cypress seed contain a significant amount of amino acids. Amino acids are the basic structural units for forming enzymes and proteins, and they also function as precursors for neurotransmitter synthesis. Furthermore, amino acids can be broken down when needed to generate energy to supply the body and maintain basal metabolic functions. In summary, the jujube seed-cypress seed herbal pair has high nutritional value and can provide a nutritional foundation for stout beer. In addition, jujube seed contains approximately 7.2% total saponins, while cypress seed contains approximately 1-2% saponins. The saponins in jujube seed can inhibit the central nervous system, regulate sleep parameters, neurotransmitters, and receptors, and alter sleep time and depth. Cypress seed can improve sleep, and its sedative effects are also attributed to saponins and total terpenes.

[0007] High hydrostatic pressure (HHP), also known as ultra-high pressure or high-pressure treatment, utilizes ultra-high pressure equipment. This equipment primarily consists of a closed high-pressure vessel, a pressure generation system (i.e., a piston acting directly or a hydraulic pump acting indirectly), a pressure transmission medium, and a temperature control system. Typically, the sample to be treated is placed in a liquid medium (usually water) after being soft-packaged. The sample is then placed in the ultra-high pressure equipment and subjected to pressures of 100–1000 MPa at room temperature or low temperature for a period of time to achieve sterilization. HHP has minimal impact on the sensory characteristics, nutritional components, and volatile flavor compounds of food, preserving its original flavor and nutritional components while ensuring food safety. Using HHP to treat a mixture of jujube seed, cypress seed, and schisandra fruit juice can maximize the preservation of their original nutritional components and effects, retain better product color, and improve overall acceptability, ensuring microbial safety and nutritional quality before fermentation. Currently, this technology is mainly used in food, while research and application of HHP for the treatment of medicinal and edible herbs are relatively limited in China. Summary of the Invention

[0008] The purpose of this invention is to provide a jujube stout beer with sleep-improving properties, its preparation method, and its application. This beer contains jujubes and has sleep-aiding effects, producing abundant and long-lasting foam. Another purpose of this invention is to provide the application of jujube stout beer in sleep-aiding beverages.

[0009] This invention is achieved by the following technical solution: a method for preparing a jujube stout beer that improves sleep, comprising the following steps:

[0010] (1) The jujube pulp and rye malt were mixed in a mass ratio of 7:0.2-15:1 and then crushed. They were baked at 180-220℃ for 20-40 minutes, turned over every 10 minutes, and then ground and pulverized through a 10-20 mesh sieve to obtain a pulp-malt mixture. The composition, sugar content and color of the pulp-malt mixture were determined.

[0011] (2) Select loaglonder Dried malt extract and the pulp malt mixture obtained in step (1) as saccharification raw materials. The loaglonder Dried malt extract and the pulp malt mixture are mixed at a mass ratio of 0.23-0.681:0.1-1 kg:kg.

[0012] (3) Mix the saccharification raw materials in step (2) with water at a mass-volume ratio of 2:1 kg / L, and then carry out saccharification. After saccharification, filter to obtain mash, adjust the pH to 5.2-5.6, and obtain wort mash. Analyze the components of the obtained wort mash by UPLC-Q-TOF-MS. Determine that the acid content in the wort mash is 520-690 mg / L, the alcohol content is 240-460 mg / L, the ketone content is 190-430 mg / L, and the total saponin content is 70-120 mg / L, thus completing saccharification.

[0013] (4) Add hot water at 78-80℃ to the wort mash obtained in step (3), filter and wash the tank to obtain filtered mash;

[0014] (5) Sour jujube seed and cypress seed are mixed in a mass ratio of 1:0.5-5:1, stir-fried at 170℃ for 5-15 minutes, cooled, and then mixed with 3 times the mass of water in a high-speed homogenizer. The mixture is then subjected to high hydrostatic pressure treatment in an ultra-high pressure equipment to obtain a mixed juice for later use. The protein content in the mixed juice is 8.8-11.9%, the total saponin content is 3.5-7.4 mg / 100ml, and the fatty acid content is 12.7-17.8%.

[0015] (6) Add the mixed juice obtained in step (5) to the filtered mash obtained in step (4) and boil it. The amount of mixed juice added is 10-15% of the volume of filtered mash. The boiling time is 40-80 minutes. Add hops twice during the boiling process. After the mash settles for 30 minutes, transfer the obtained wort to the fermentation tank and cool it naturally to 15-20°C. Then, oxygenate the wort. Add English Ale yeast CN36 and American West Coast yeast Mangrove Jack M44 to the wort. Ferment at a low temperature of 4°C for three days and then discharge the condensate.

[0016] (7) After fermentation, store the beer at a temperature of ≤0℃ and maintain the pressure at 0.14-0.16MPa. When the pressure is lower than this range, add food-grade carbon dioxide to the fermentation tank through the exhaust valve. After 7-15 days of storage, the yeast will gradually sink and clarify. After 3-5 days of storage, remove the bottom yeast mud, add bentonite and let it stand for a week. Centrifuge and filter to obtain the mature beer liquid of jujube stout.

[0017] Furthermore, in step (1): the jujube pulp and rye malt are mixed at a mass ratio of 12:1 and then crushed and baked at 140-220℃ for 20-40 minutes.

[0018] In step (2): loaglonder malt extract and pulp malt mixture are mixed at a mass ratio of 0.68:1 kg:kg.

[0019] In step (3), the ratio of saccharification raw materials to water is 1:3 kg / L. The specific steps of saccharification are: raise the temperature to 45°C and maintain it for 15 min; raise the temperature to 52°C and maintain it for 20 min; raise the temperature to 65°C and maintain it for 60 min; raise the temperature to 68°C and add distilled water or lactic acid to adjust the pH to 5.2-5.6 during the saccharification process.

[0020] The specific method of filtration in step (4) is as follows: pump the wort into the filter tank, let it stand for 20 minutes and then filter it. Wash the filter tank with water at 70-78℃. Return the filtered liquid to the cleaned filter tank, filter and wash the tank again, combine the two filtrates, and divide the filtered tank wash into two parts. The volume ratio of wort to hot water for tank washing is 1:1.

[0021] In step (5), jujube seed and cypress seed are mixed in a mass ratio of 4:1 and stir-fried in an oil bath at 170℃ for 10 minutes; in step (5), the high-speed homogenizer speed is 8000 rpm and the time is 15 minutes; the specific steps of the high hydrostatic pressure treatment are as follows: the homogenized mixture is boiled at 95℃ for 5 minutes, then immediately cooled to 25℃ with cold water, and then the mixture is placed in an aluminum-coated polyethylene bag, with water as the conducting medium, and placed in an ultra-high pressure device at a pressure of 500 MPa for 2 minutes, with a pressurization rate of 120-150 MPa / min and a depressurization time of 3 seconds.

[0022] The hops mentioned in step (6) are any one of Columbus hops, Crystal imported American hops, or Chinook hops. The amount of hops added is 0.1%-0.5% of the filtered mash volume. 50% of the hops are added 10 minutes after the initial boil, and the remaining 50% is added 10 minutes before the final boil. The mass ratio of English ale yeast CN36 to American West Coast yeast M44 is 2:1, and the amount of yeast added is 1.0-1.5 × 10⁻⁶. 7 cells / mL;

[0023] The specific low-temperature fermentation method is as follows: After adding yeast to the wort and transferring it to the fermentation tank, the temperature is naturally raised to 20-25℃ and the sugar content drops to 5-7. The tank is then sealed and pressurized to 0.12-0.14 MPa. The diacetyl content in the fermentation tank is measured periodically. When the diacetyl content in the fermentation tank drops to ≤0.08 mg / L, the temperature is lowered to 1-5℃ at a rate of 0.3-0.5℃ / h, and then the fermentation tank is lowered to 0-0.5℃ at a rate of 0.1℃ / h for 2-9 days of fermentation.

[0024] The foam persistence of the mature wine obtained in step (7) was determined. The specific determination method is as follows: 200 mL of mature wine was flowed from a height of 900 mm to the surface of the same solution, and the foam volume was measured. The foam stability was represented by the foam volume after 5 minutes. The test temperature was (40±1)℃. In the wine quality determination, the original wort concentration was determined by a hydrometer and was ≥15°p, the IBU value was ≥30IBU, and the color was ≥60 EBC.

[0025] The present invention also provides a jujube stout beer with sleep-improving properties obtained by the preparation method described above.

[0026] The present invention also provides the application of the aforementioned jujube stout beer, which has the effect of improving sleep, in the preparation of sedative and sleep-aiding foods or beverages.

[0027] The jujube stout beer prepared by this invention has the following advantages and effects:

[0028] In this invention, the pigments from the pulp and peel of jujube fruit provide a basis for color variations in stout beer, increasing its color value by 5-8 EBC. Simultaneously, the sugar in the pulp becomes more concentrated, increasing the sugar content. After roasting, the sugar content can increase to 20%. This increased sugar content provides more sugar for the beer's mashing process, offering energy and nutrients for fermentation. The roasted jujube pulp also imparts a sweet and sour jujube flavor to the beer, balancing the caramel and fruit tastes, eliminating noticeable bitterness, and resulting in a smooth mouthfeel.

[0029] The fermentation agents ultimately selected in this invention are jujube pulp and rye malt. The jujube pulp plays a crucial role; after being mixed and roasted, the amino acids and sugars they contain undergo Markovnikov and Maillard reactions. During these reactions, sugars and amino acids condense, generating more colorless intermediates and melanoidins, which enrich the flavor, deepen the color, and impart a strong malt and caramel aroma. Simultaneously, the hop aroma and bitterness become prominent, exhibiting a degree of aromatic complexity.

[0030] The fermentation process uses a mixture of roasted jujube pulp and malt to create a new beer flavor, expanding the market and increasing consumer choice. Fermentation with jujube pulp roasted at 180-220℃ and malt extract allows the dark pigment from the roasted pulp to enhance the stout's color, while the malt extract compensates for the insufficient starch content of the jujube pulp. Furthermore, the calming and soothing effects of jujube pulp and kernels are incorporated into the stout, filling a functional gap in the market and increasing the availability of sleep aid products.

[0031] This invention creatively replaces a portion of the fermentation raw materials with jujube pulp and adds jujube kernels and cypress kernels during the fermentation process, giving the beer a sleep-aiding function. The unique variety and flavor of the finished beer can meet consumer demand. Furthermore, all the added materials are natural raw materials with rich nutritional components, which can provide nutrients to the human body. While improving the competitiveness of stout beer in the market, it can also promote green and sustainable development.

[0032] Adding a mixture of roasted jujube seeds and cypress seeds treated with high hydrostatic pressure after saccharification and before fermentation alters the properties of the materials, achieves sterilization, denatures or inactivates enzymes, extends the product's shelf life, and preserves its nutritional and sensory characteristics. While retaining nutrients, it ensures microbial safety before fermentation and also provides an effective material basis for the sleep-inducing effect of stout beer.

[0033] This invention utilizes roasted jujube pulp and malt as saccharification raw materials for stout beer. The polysaccharides and organic acids in the jujube pulp enhance the beer's sweet and sour taste. Simultaneously, roasting jujube kernels and cypress seeds produces a coffee-like flavor, adding layers of complexity to the stout's flavor profile. Furthermore, the fatty acids in these herbs help regulate the pH of the saccharification liquid, aiding in beer fermentation. Using jujube pulp, jujube kernels, and cypress seeds as stout beer raw materials increases the protein and saponin content, resulting in more foam, longer foam duration, and effectively improving the stout's quality characteristics. Attached Figure Description

[0034] Figure 1 The effects of heat treatment on the quality of jujube pulp are shown in the figure. Figure A shows the effect of heat treatment on the total flavonoids in jujube pulp; B shows the effect of heat treatment on the antioxidant capacity of jujube pulp; C shows the effect of heat treatment on the sugar content of jujube pulp; and D shows the effect of heat treatment on the color of jujube pulp.

[0035] Figure 2 The results of component analysis of wort;

[0036] Figure 3 Results showing the effect of the amount of mixed juice added on beer foam persistence;

[0037] Figure 4 The effect of the amount of jujube pulp added on the sensory evaluation of beer. Detailed Implementation

[0038] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are some embodiments of the present invention, but not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0039] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains, and all materials publicly cited herein and cited by them are incorporated herein by reference.

[0040] Equivalent technologies of the specific embodiments described herein that are readily apparent to those skilled in the art through routine experimentation are included in this application.

[0041] Unless otherwise specified, the experimental methods used in the following examples are conventional methods. Unless otherwise specified, the instruments and equipment used in the following examples are all standard laboratory instruments and equipment; unless otherwise specified, the experimental materials used in the following examples were all purchased from regular biochemical reagent stores.

[0042] The English ale yeast CN36, the American West Coast yeast M44, and hops used in this invention are all commercially available.

[0043] I. Effects of heat treatment on the quality of jujube pulp

[0044] Jujube pulp was placed in an oven and baked at temperatures of 140, 160, 180, 200, and 220°C for 20, 25, 30, 35, and 40 minutes, respectively, turning the pulp every 10 minutes. The pulp was then pulverized and passed through a 20-mesh sieve. The effect of heat treatment on the quality of the jujube pulp was determined by measuring its total flavonoid content, color, and sugar content.

[0045] Determination of total flavonoids: Accurately pipette 1.0 mL of ethanol extract of jujube pulp into a 10 mL volumetric flask, add 0.5 mL of 5% sodium nitrite solution, shake well, and let stand for 6 min. Then add 0.5 mL of 10% aluminum nitrate solution, let stand for 6 min, add 4.0 mL of 4% sodium hydroxide, and dilute to the mark with 60% ethanol (v / v), shake well, and let stand for 15 min. Use distilled water as a blank control, and measure the absorbance at a wavelength of 510 nm. Calculate the total flavonoid content: The result is expressed as rutin (mgRE / 100gmd). The standard curve is plotted using rutin standard solution.

[0046] Colorimetry: The color of the jujube pulp was measured using a colorimeter to obtain the brightness value (L*), redness value (a*), and yellowness value (6*).

[0047] ΔE represents the color difference between the heat-treated jujube color and the control group, calculated using the following formula: In the formula: L*, a*, b* are the color values ​​of jujube pulp under each heat treatment; L*0, a*0, b*0 are the color values ​​of the control group.

[0048] Sugar content: Grind the roasted jujube pulp and add water to make jujube pulp paste. Then add an appropriate amount of water to make a uniform pulp solution. Use a saccharimeter to measure the sugar content. After calibrating the instrument, pour the prepared pulp solution into the sample cell of the refractometer to measure its sugar content.

[0049] The final results showed that the total flavonoid content and sugar content of jujube pulp were highest when baked at 160℃, while the antioxidant capacity and color were stronger when baked for 35 minutes. Taking all factors into consideration, baking at 160℃ for 35 minutes was the optimal heat treatment for jujube pulp.

[0050] II. Compositional Analysis of Wheat Mash After Saccharification

[0051] The quality of the wort directly affects the quality of the beer after wort fermentation. The main substances affecting beer quality include alcohols, aldehydes, acids, esters, and ketones. These substances are important indicators for evaluating beer quality. The wort obtained in step 4 was analyzed for components. UPLC-Q-TOF-MS analysis showed that esters accounted for approximately 9.2%, ketones for approximately 6.1%, and aldehydes for approximately 4.6%. The total saponin content was determined by colorimetric method to be 114 mg / L.

[0052] Liquid chromatography method: Column: ZORBAX Eclipse Plus C18 (2.1 mm × 50 mm, 1.8 μm); Column temperature: 30℃; Injection volume: 10 μL; Flow rate: 0.3 mL / min; Positive / negative ion mode: Phase A: 1‰ formic acid water / 1 mmol / L ammonium fluoride solution, Phase B: 1‰ formic acid acetonitrile / acetonitrile; Gradient elution: Initial mobile phase: 95% A; 0~2 min: 95% A; 2~20 min: 95%~0% A; 20~25 min: 0% A.

[0053] Mass spectrometry conditions: positive / negative ion mode; ion source: AJS; drying gas flow rate: 11 L / min / 7 L / min; drying gas temperature: 350 ℃ / 325 ℃; nebulizer: 35 psi / 32 psi; sheath gas flow rate: 10 L / min; sheath gas temperature: 350 ℃; capillary voltage: 3.5 kV; reference ions (m / z): 121.0509, 922.0098 / 1,112.9855, 1,033.9881.

[0054] The detector and injection port temperatures were both 260℃; the column oven temperature was increased as follows: initial temperature 50℃ (2 min), increased to 70℃ (2 min) at 5℃ / min, increased to 110℃ at 5℃ / min, and increased to 250℃ (2 min) at 10℃ / min; nitrogen, hydrogen, and air flow rates were 4.2 mL / min, 45 mL / min, and 450 mL / min, respectively; gas chromatography column: HP-FEAP (50 mm x 0.32 mm x 1.00 μm).

[0055] III. Determination of the components of the mixed juice of jujube seed and cypress seed and the finished beer

[0056] Sour jujube seed and cypress seed contain proteins and saponins, which significantly influence beer foam. The protein and saponin content of the jujube seed-cypress seed mixture and the finished beer were determined. Fatty acids in the mixture and reducing sugars in the mature beer were also measured. Protein content was determined using the Coomassie Brilliant Blue method. The jujube seed-cypress seed mixture contained 8.8-11.9% protein, while the finished beer contained 13.4-18.1%. Saponin content was determined using a colorimetric method. The jujube seed-cypress seed mixture contained 3.6774 mg / 100ml of saponins, while the finished beer contained 6.8-9.9 mg / 100ml of total saponins. Fatty acid content in the mixture was determined using chromatography, ranging from 12.7% to 17.8%. Reducing sugar content in the mature beer was determined using a colorimetric method, ranging from 4% to 6.2%.

[0057] Protein determination: Add different amounts of standard protein solution sequentially to clean test tubes, and bring the volume up to 1.0 mL with water. Determine the standard curve using at least 5 sampling points. Add pure water to another test tube as a blank control. Add 1.0 mL of a mixture of jujube seed and cypress seed juice, along with the solution remaining after brewing, to another clean test tube. Prepare at least 3 parallel samples. Add 5.0 mL of Coomassie Brilliant Blue reagent to each tube, and immediately mix thoroughly using a vortex mixer after each addition. After mixing and letting stand for 10 minutes, measure the absorbance at 595 nm using a UV-Vis spectrophotometer, with the tube containing pure water serving as a blank control. The standard protein concentration (μg·mL⁻¹) is used as the standard control. -1 Plotting the absorbance of the corresponding protein standard tube at 595 nm (A595nm) on the x-axis yields a standard curve for protein content determination. The protein content of the sample is then calculated based on this standard curve. The results show that the mixed juice of jujube seed and cypress seed contains 26.3-28.1% protein, while the protein content in beer after brewing is 18.4-22.1%.

[0058] Fatty acid determination: Analytical instruments: GC-HP6890, FID detector, HP7683 series autosampler. Chromatographic column: HP19095F-123, 30M*0.53mm; 10℃ / min. Chromatographic conditions: Column temperature: 35~110℃ (heating rate 10℃ / min, hold for 3 min), 110~210℃ (heating rate 5℃ / min, hold for 5.5 min). Vaporization temperature: 250℃, FID temperature: 300℃, hydrogen: 40.0 mL / min, nitrogen: 3.3 mL / min, air: 400 mL / min, column head pressure: 15.0 kPa, splitless, linear velocity: 24 cm / min, tail purge: 30 mL / min, injection 1 μL.

[0059] Effect of the amount of mixed juice of jujube seed and cypress seed on the foam persistence of beer: The amount of mixed juice of jujube seed and cypress seed added was 10, 11, 12, 13, 14 and 15% of the filtered mash. The foam persistence of the finished beer brewed with different amounts of mixed juice was determined by the stopwatch method, the second method in the analytical methods of the national standard GBT 4928-2008.

[0060] Place the bubble holder on the iron stand base, fix the iron ring 3cm from the rim of the glass, open the bottle cap, place the bottle mouth on the iron ring, and pour the wine sample into the glass at a uniform flow rate along the center line of the glass until the foam height is level with the rim of the glass (the time to fill the glass should be controlled within 4-8 seconds). Start the stopwatch at the same time. Observe the rise of the foam, record the shape of the foam (including color and fineness) and the amount of foam clinging to the glass, and record the time from when the foam fills the glass to when it disappears (revealing 0.05cm of the wine surface). Air circulation is strictly prohibited during the test, and the sample bottle should not be shaken before the test. The results are expressed as integers, and the test temperature is (40±1)℃. The test showed that when the amount of mixed juice added was 13%, the foam persistence was high. The foam persistence of the finished wine was measured, and the volume of the foam after 5 minutes was 18-25 cm³. 3 Taking all factors into consideration, the amount of mixed juice added was chosen to be 13% of the filtered mash.

[0061] IV. Single-factor investigation of preparation process

[0062] 1. The effect of the amount of jujube pulp added on the sensory evaluation of beer

[0063] The brewing raw materials were loaglonder dried malt extract and pulp malt mixture in a ratio of 0.23-0.681:0.1-1 (kg:kg) and brewed separately in the following proportions: 1 (0.5:0.8), 2 (0.68:1), and 3 (0.4:0.6). After brewing, the three types of jujube stout beer were taken and kept at a constant temperature of 12-15℃. They were poured into clean, dry beer tasting glasses at the same height (3 cm from the rim) and flow rate. The beer samples were placed in a bright place for observation, and the clarity, suspended matter, and sediment were recorded. The color, fineness, and clinging of the foam were observed visually. The tasting glasses containing the beer samples were placed under the nostrils to smell the aroma. After swirling the beer, the aroma of hops and any off-odors were smelled again. An appropriate amount of beer sample was drunk, and the beer was evaluated according to the taste characteristics that the sample should possess. Five men and five women were selected to give a sensory evaluation using the sensory evaluation form (Table 1). The evaluation results are shown below. Figure 3 Taking all factors into consideration, we selected ingredient No. 2 (0.68:1) for brewing.

[0064] Table 1: Sensory Evaluation Table

[0065]

[0066] 2. The impact of hop selection and addition amount on beer quality

[0067] The selection of hops serves two purposes in this invention: firstly, the bitter acids (α- and β-acids) in hops provide the material basis for the calming effect of stout beer; secondly, the bitter compounds and aromatic substances contained in hops are released during the brewing process, imparting bitterness and aroma to the beer. Three types of hops (Columbus hops, Crystal imported hops from the US, and Chinook hops) were selected and added at a rate of 0.4% to brew stout beer (all purchased from Super Malt Beijing Trading Co., Ltd.). Subsequently, five men and five women were selected to evaluate the taste and aroma of the beer brewed with different hops according to the sensory evaluation table (Table 2) (Table 3).

[0068] Table 2. Bitter Acid Content by Hop Type

[0069]

[0070] Table 3. Effects of hops on beer quality

[0071]

[0072] Considering all factors, Columbus hops were selected as the hops for brewing Suanzao Stout beer. A single-factor study was conducted on the amount of hops added. The hop addition amounts were 0.1%, 0.2%, 0.3%, 0.4%, and 0.5% of the boiled mash. The alcohol content of the beer at the end of brewing was measured using an alcohol meter, and the residual sugar content was determined using Fehling's reagent direct titration. The results are shown in Table 4. Considering the impact of hop selection and addition amount on beer quality, Columbus hops were selected for fermentation, with an addition amount of 0.4% of the boiled mash.

[0073] Table 4. Effect of hop addition on beer quality

[0074]

[0075] V. Preparation of Jujube Stout Beer:

[0076] Example 1: Jujube pulp and rye malt were mixed in a 7:0.5 ratio and then pulverized. The mixture was then baked in an oven at 180°C for 25 minutes, with the mixture being turned over every 10 minutes. The degree of pulverization was such that the mixture passed through a 10-20 mesh sieve. The composition, sugar content, and color of the baked mixture were measured to obtain the pulp and malt mixture.

[0077] Loaglonder Dried malt extract and a mixture of pulp and malt were added at a ratio of (0.5:0.8) (kg:kg) as saccharification raw materials. During saccharification, the material-to-liquid ratio was 1:3 (kg:L). Water was injected into the saccharification tank and heated to 78°C. The saccharification raw materials were slowly added to the saccharification tank while stirring to ensure thorough mixing. After saccharification, the mash was filtered and the pH was adjusted to between 5.2 and 5.6 to obtain wort mash. The composition was analyzed, and the wort mash contained approximately 550 mg / L of acids, 250 mg / L of alcohols, and 210 mg / L of ketones. Hot water at 78-80°C was pre-introduced into the filtration tank to filter the wort mash and wash the tank to obtain filtered mash.

[0078] Take appropriate amounts of jujube seeds and cypress seeds in a mass ratio of 1:0.8, stir-fry them in an oil bath at 170 ℃ for 5 minutes, let them cool, add 3 times the amount of water to homogenize, and then perform high hydrostatic treatment in an ultra-high pressure device to obtain a mixed juice; the protein content in the mixed juice is determined to be 9.4%, and the total saponin content is 7.8 mg / 100 ml.

[0079] The mixed juice of jujube seed and cypress seed was added to the filtered mash after filtration and washing, and then boiled. The amount of mixed juice added was 10% of the filtered mash, and the boiling time was 40 minutes. The total saponins of the mixed juice and the foam persistence of the finished beer with different addition ratios of mash were measured. Hops were added twice during the boiling process. The hop variety was Crystal American imported hops, and the addition amount was 0.1%. The mash after adding hops was pumped into a vortex sedimentation tank, allowed to settle for 30 minutes, and then transferred to a fermentation tank. The wort was cooled to 15-20 °C, and oxygen was introduced into the wort. After aeration, a 2:1 ratio of English ale yeast CN36 and American West Coast yeast (Red Jack M44) was added. After low-temperature fermentation, the condensate was discharged.

[0080] After low-temperature fermentation, the beer is stored at a temperature not exceeding 0°C, with the pressure maintained at 0.14-0.16 MPa. When the pressure falls below this range, food-grade carbon dioxide is added to the fermentation tank through the vent valve. After 7-15 days of storage, the yeast gradually settles and clarifies. After another 3-5 days of storage, the bottom yeast sludge is removed, and bentonite is added and allowed to stand for a week. After centrifugation and filtration, the mature beer liquid of jujube stout is obtained. The quality and content of the mature beer liquid are determined. The total saponin content is 3.8 mg / 100ml, the protein content is 15.5%, and the reducing sugar content is 3.6%. The original wort concentration is 1.012°p, the IBU value is 30, and the color is 66 EBC.

[0081] Example 2: Jujube pulp and rye malt were mixed in a 9:1 ratio, pulverized, and baked in an oven at 180 ℃ for 20 min, turning every 10 min. The pulverization was such that the mixture passed through a 10-20 mesh sieve. The composition, sugar content, and color of the baked product were measured to obtain a pulp-malt mixture.

[0082] Loaglonder dried malt extract and a mixture of pulp and malt were added as saccharification raw materials at a ratio of (0.68:1) (kg:kg), with a material-to-liquid ratio of 1:3 (kg:L). Water was added to the saccharification tank and heated to 78°C. The saccharification raw materials were slowly added to the tank while stirring to ensure thorough mixing. After saccharification, the mash was filtered, and the pH was adjusted to between 5.2 and 5.6 to obtain wort mash. Analysis of the wort mash revealed approximately 570 mg / L of acids, 310 mg / L of alcohols, and 210 mg / L of ketones. Hot water at 78-80°C was pre-introduced into the filtration tank to filter the wort mash and wash the tank, yielding filtered mash.

[0083] Take appropriate amounts of jujube seed and cypress seed in a mass ratio of 4:1 (m:m), stir-fry them in an oil bath at 170℃ for 10 minutes, let them cool, add 3 times the amount of water to homogenize, and then perform high hydrostatic treatment in an ultra-high pressure device to obtain a mixed juice. The protein content in the mixed juice was determined to be 9.1%, and the total saponin content was 5.6 mg / 100ml.

[0084] Add the mixed juice of jujube seed and cypress seed to the filtered mash after filtration and washing, and boil. The amount of the mixed juice added is 11% of the filtered mash. The boiling time is 50 min. During the boiling process, Crystal imported American hops are added twice, with an addition amount of 0.4%. The resulting mash is pumped into a vortex sedimentation tank and allowed to settle for 30 min. Then, it is transferred to a fermentation tank, and the wort is cooled to 15-20 ℃ and oxygen is introduced into the wort. Subsequently, English ale yeast CN36 and American West Coast yeast (Red Jack M44) are added in a ratio of 2:1. The amount of yeast added is (1.0~1.5)×107 cells / mL. After low-temperature fermentation, the condensate is discharged.

[0085] After low-temperature fermentation, the beer is stored at a temperature not exceeding 0°C and a pressure maintained at 0.14-0.16 MPa. When the pressure falls below this range, food-grade carbon dioxide is added to the fermentation tank through the vent valve. After 7-15 days of storage, the yeast gradually settles and clarifies. After another 3-5 days of storage, the yeast sludge at the bottom is removed, bentonite is added, and the mixture is left to stand for one week. After centrifugation and filtration, the mature beer liquid of jujube stout is obtained. The quality and content of the mature beer liquid are then determined. The total saponin content is 4.4 mg / 100ml, the protein content is 21.1%, and the reducing sugar content is 4.7%. The original wort concentration is 1.016°p, the IBU value is 3840 BU, and the color is 77 EBC.

[0086] Example 3: Jujube pulp and rye malt were mixed in a 12:1 ratio, pulverized, and baked in an oven at 200℃ for 35 minutes, turning every 10 minutes. The pulverization was such that the mixture passed through a 10-20 mesh sieve. The composition, sugar content, and color of the baked product were measured to obtain a pulp-malt mixture.

[0087] Loaglonder dried malt extract and a mixture of pulp and malt were added as saccharification raw materials at a ratio of (0.4:0.6) (kg:kg), with a material-to-liquid ratio of 1:3 (kg:L). Water was added to the saccharification tank, and the temperature was raised to 78°C. The saccharification raw materials were slowly added to the saccharification tank while stirring continuously to ensure thorough mixing. After saccharification, the mash was filtered, and the pH was adjusted to between 5.2 and 5.6 to obtain wort mash. Analysis of the wort mash composition revealed approximately 630 mg / L of acids, 400 mg / L of alcohols, and 400 mg / L of ketones. Hot water at 78-80°C was pre-introduced into the filtration tank to filter the wort mash and wash the tank, obtaining filtered mash.

[0088] Take appropriate amounts of jujube seed and cypress seed in a mass ratio of 3:1, stir-fry them in an oil bath at 170 ℃ for 15 min, let them cool, add 3 times the amount of water to homogenize, and then perform high hydrostatic treatment in an ultra-high pressure device to obtain a mixed juice; the protein content in the mixed juice was determined to be 11.9%, and the total saponin content was 7.4 mg / 100ml.

[0089] The mixed wort was added to the filtered and washed mash and then boiled. The amount of mixed wort added was 13% of the filtered mash, and the boiling time was 80 minutes. Crystal American imported hops were added twice during the boiling process, with the amount of hops added being 0.4%. The resulting mash was pumped into a vortex sedimentation tank and allowed to settle for 30 minutes before being transferred to a fermentation tank. The wort was cooled to 15-20°C and oxygen was introduced into the wort. Subsequently, English ale yeast CN36 and American West Coast yeast (Red Jack M44) were added in a ratio of 2:1, with the amount of yeast added being (1.0-1.5) × 10⁷ cells / mL. After low-temperature fermentation, the condensate was discharged.

[0090] After low-temperature fermentation, the beer is stored at a temperature not exceeding 0°C, with the pressure maintained at 0.14-0.16 MPa. When the pressure falls below this range, food-grade carbon dioxide is added to the fermentation tank through the vent valve. After 7-15 days of storage, the yeast gradually settles and clarifies. After another 3-5 days of storage, the bottom yeast sludge is removed, bentonite is added, and the mixture is left to stand for one week. After centrifugation and filtration, the mature beer liquid of jujube stout is obtained. The quality and content of the mature beer liquid are then determined. The total saponin content is 7.4 mg / 100ml, the protein content is 23.4%, and the reducing sugar content is 6.6%. The original wort concentration is 1.018°p, the IBU value is 40 BU, and the color is 90 EBC.

[0091] Experiment Example 1: Experiment on the use of jujube stout beer to prolong the sleep time of sodium pentobarbital

[0092] Male SD mice were selected and acclimatized for 7 days. After weighing, 180 mice were randomly divided into three experimental groups of 60 mice each. The adult daily dose was converted to a medium-dose group for animal experiments. Mice in each group were randomly divided into low-dose, medium-dose, and high-dose groups (0.5, 1.0, and 2.0 g / kg, administered via gavage with 0.2 ml / 10g of jujube-based stout beer), a positive control group (0.45 g / kg, a suspension of jujube seed anxieties prepared as 2.25 g / 100 ml, administered via gavage with 0.2 ml / 10g), and a blank control group (administered via gavage with the same volume of distilled water). Each group contained 12 mice. All mice were administered via gavage once daily for 7 days. Statistical analysis showed no significant differences in body weight or age among the groups (P>0.05). After inducing sleep with an appropriate dose of sodium pentobarbital, a predetermined dose of jujube-based stout beer was administered to observe its effect on prolonging sleep duration. Increased sleep duration indicates that jujube-flavored Shitao beer has a synergistic effect on pentobarbital-induced sleep. Preliminary experiments confirmed that 40 mg / kg of pentobarbital sodium could induce sleep in all animals, with a sleep duration of <60 min. After 7 days of continuous gavage, 30 min after the last administration, mice in each group were given a predetermined dose of pentobarbital sodium (40 mg / kg, 0.2 ml / 10 g) via intraperitoneal injection. The criterion for sleep in mice was the disappearance of the righting reflex for more than 60 seconds. The effect of jujube-flavored Shitao beer on the sleep duration induced by pentobarbital sodium was observed. The results are shown in Table 5. The results showed that after 7 days of continuous administration, the sleep duration of animals in the medium-dose (1 g / kg), high-dose (2 g / kg) groups and the positive control group was significantly increased compared to the blank control group (P<0.05), indicating that sufficient jujube-flavored Shitao beer can prolong the sleep duration induced by pentobarbital sodium in mice.

[0093] Table 5. Effects of experimental drugs on prolonging sleep duration with sodium pentobarbital (S, ±s)

[0094]

[0095] Experimental Example 2: GC-MS Determination of Components in Jujube Seed and Jujube Stout Beer

[0096] Sample preparation: Accurately weigh 2g of roasted jujube seed powder, take 6 portions, place them in a Soxhlet extractor, add 50ml of petroleum ether and soak overnight, then add 40ml, heat at 90℃ under reflux for 4 h, add anhydrous magnesium sulfate to the petroleum ether extract to absorb water, filter, and recover the petroleum ether under reduced pressure to obtain jujube seed fatty oil. Take 50ml of fatty oil and add 150ml of TMCS (trimethylchlorosilane) derivatization reagent, place in a constant temperature shaking metal bath at 90℃ and 300 r / min, derivatize for 1.5 h, filter through a 0.22 μm microporous membrane to obtain the GC-MS test solution. Take 50ml from each test solution to prepare a QC sample.

[0097] Analytical conditions: Gas chromatography conditions: HP-5 capillary column (30 m x 0.25 mm x 0.25 mm), carrier gas was high-purity helium, flow rate was 1.0 mL / min, split ratio was 100:1, injection volume was 0.2 µl, injection port temperature was 250 °C, transfer line temperature was 280 °C, temperature program: initial temperature 150 °C, hold for 1 min, then increase to 215 °C at 5 °C / min, hold for 18 min, then increase to 240 °C at 5 °C / min, hold for 6 min, then increase to 270 °C at 10 °C / min, hold for 13 min.

[0098] Mass spectrometry conditions: EI ionization 70 eV, ion source temperature 230 ℃, quadrupole temperature 150 ℃, scan range 50-500 m / z, solvent delay 3 min.

[0099] Statistical methods: Mass spectrometry data acquired by GC-MS were output in XML file format, and then deconvolution, peak matching, and peak integration were performed using the xcms package in R software. The results are shown in Table 6.

[0100] Table 6. GC-MS determination of components in jujube stout beer

[0101]

[0102] The aroma components of coffee are mainly composed of aldehydes, ketones, esters, alcohols, and nitrogen-containing oxides such as furans, pyrazines, pyridines, and pyrroles. GC-MS analysis of stout beer shows that fatty acids such as palmitic acid, myristic acid, linoleic acid, 13-oleic acid, stearic acid, and eicosanoic acid, as well as alcohols such as stigmasterol and β-sitosterol, are common components of roasted jujube seeds and coffee. These components, in addition to adding coffee aroma to stout beer, also provide complex taste and rich flavor, bringing a more robust and profound layering to the beer. Furthermore, they may interact with other components in the beer, producing new chemical reactions that further enrich the beer's flavor characteristics.

[0103] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for preparing a jujube stout beer that helps improve sleep, characterized in that: Includes the following steps: (1) The jujube pulp and rye malt were mixed in a mass ratio of 7:0.2-15:1 and then crushed. They were baked at 140-220℃ for 20-40 minutes, turning them over every 10 minutes. Then they were ground and pulverized through a 10-20 mesh sieve to obtain a pulp-malt mixture. The composition, sugar content and color of the pulp-malt mixture were determined. (2) Select loaglonder Dried malt extract and the pulp malt mixture obtained in step (1) as saccharification raw materials. The loaglonder Dried malt extract and the pulp malt mixture are mixed at a mass ratio of 0.23-0.681:0.1-1 kg:kg. (3) Mix the saccharification raw materials in step (2) with water at a mass-volume ratio of 1:3 kg / L, and then carry out saccharification. After saccharification, filter to obtain mash, adjust the pH to 5.2-5.6, and obtain wort mash. Analyze the components of the obtained wort mash by UPLC-Q-TOF-MS. Saccharification was completed when the levels of acids in the wort mash were 520-690 mg / L, alcohols were 240-460 mg / L, ketones were 190-430 mg / L, and total saponins were 70-120 mg / L. (4) Add hot water at 78-80℃ to the wort mash obtained in step (3), filter and wash the tank to obtain filtered mash; (5) Sour jujube seed and cypress seed are mixed in a mass ratio of 1:0.5-5:1, stir-fried at 170℃ for 5-15 minutes, cooled, and then mixed with 3 times the mass of water in a high-speed homogenizer. The mixture is then subjected to high hydrostatic pressure treatment in an ultra-high pressure equipment to obtain a mixed juice for later use. The protein content in the mixed juice is 8.8-11.9%, the total saponin content is 3.5-7.4 mg / 100ml, and the fatty acid content is 12.7-17.8%. (6) Add the mixed juice obtained in step (5) to the filtered mash obtained in step (4) and boil it. The amount of mixed juice added is 10-15% of the volume of filtered mash. The boiling time is 40-80 minutes. Add hops twice during the boiling process. After the mash settles for 30 minutes, transfer the obtained wort to the fermentation tank and cool it naturally to 15-20°C. Then, oxygenate the wort. Add English Ale yeast CN36 and American West Coast yeast Mangrove Jack M44 to the wort. After three days of low-temperature fermentation, discharge the condensate. (7) After fermentation, store the beer at a temperature of ≤0℃ and maintain the pressure at 0.14-0.16MPa. When the pressure is lower than this range, add food-grade carbon dioxide to the fermentation tank through the exhaust valve. After 7-15 days of storage, the yeast will gradually sink and clarify. After 3-5 days of storage, remove the bottom yeast mud, add bentonite and let it stand for a week. Centrifuge and filter to obtain the mature beer liquid of jujube stout.

2. The preparation method according to claim 1, characterized in that: In step (1): the jujube pulp and rye malt are mixed at a mass ratio of 12:1 and then crushed and baked at 140-220℃ for 20-40 minutes.

3. The preparation method according to claim 1, characterized in that: In step (2): loaglonder malt extract and pulp malt mixture are mixed at a mass ratio of 0.68:1 kg:kg.

4. The preparation method according to claim 1, characterized in that: The specific steps of saccharification in step (3) are as follows: raise the temperature to 45℃ and maintain it for 15 minutes; raise the temperature to 52℃ and maintain it for 20 minutes; raise the temperature to 65℃ and maintain it for 60 minutes; raise the temperature to 68℃ and add distilled water or lactic acid to adjust the pH to 5.2-5.6 during the saccharification process.

5. The preparation method according to claim 1, characterized in that: The specific method of filtration in step (4) is as follows: pump the wort into the filter tank, let it stand for 20 minutes and then filter it. Wash the filter tank with water at 70-80℃. Return the filtered liquid to the cleaned filter tank, filter and wash the tank again, combine the two filtrates, and divide the filtered tank wash into two parts. The volume ratio of wort to hot water for tank washing is 1:

1.

6. The preparation method according to claim 1, characterized in that: In step (5), jujube seeds and cypress seeds are mixed in a mass ratio of 4:1 and stir-fried in an oil bath at 170℃ for 10 minutes. The high-speed homogenizer operates at 8000 rpm for 15 minutes. The specific steps for high hydrostatic pressure treatment are as follows: the homogenized mixture is boiled at 95°C for 5 minutes, then immediately cooled to 25°C with cold water. The mixture is then placed in an aluminum-coated polyethylene bag, with water as the conductive medium, and placed in an ultra-high pressure device at 500 MPa for 2 minutes. The pressurization rate is 120-150 MPa / min, and the depressurization time is 3 seconds.

7. The preparation method according to claim 1, characterized in that: In step (6): the amount of mixed juice added is 13% of the volume of filtered mash; the hops are any one of Columbus hops, Crystal imported American hops, or Chinook hops, and the amount of hops added is 0.1%-0.5% of the volume of filtered mash, with 50% of the hops added 10 minutes after the initial boil and the remaining 50% added 10 minutes before the final boil; the mass ratio of English ale yeast CN36 to American West Coast yeast M44 is 2:1, and the amount of yeast added is 1.0-1.5 × 10⁻⁶. 7 cells / mL; The specific low-temperature fermentation method is as follows: After adding yeast to the wort and transferring it to the fermentation tank, the temperature is naturally raised to 20-25℃ and the sugar content drops to 5-7. The tank is then sealed and pressurized to 0.12-0.14 MPa. The diacetyl content in the fermentation tank is measured periodically. When the diacetyl content in the fermentation tank drops to ≤0.08 mg / L, the temperature is lowered to 1-5℃ at a rate of 0.3-0.5℃ / h, and then the fermentation tank is lowered to 0-0.5℃ at a rate of 0.1℃ / h for 2-9 days of fermentation.

8. The preparation method according to claim 1, characterized in that: The foam persistence of the mature wine obtained in step (7) was determined. The specific determination method is as follows: 200 mL of mature wine was flowed from a height of 900 mm to the surface of the same solution, and the foam volume was measured. The foam stability was represented by the foam volume after 5 minutes. The test temperature was (40±1)℃. In the wine quality determination, the original wort concentration was determined by a hydrometer and was ≥15°p, the IBU value was ≥30 IBU, and the color was ≥60 EBC.

9. A jujube stout beer that helps improve sleep, obtained by any of the preparation methods described in claims 1-5.

10. The use of the jujube stout beer of claim 9, which helps improve sleep, in the preparation of food products that help improve sleep.

11. The application according to claim 10, characterized in that: The food mentioned is a beverage.

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