Stirring and cold extraction preparation method of coffee liquid

Abstract

The invention relates to the technical field of coffee liquid preparation, in particular to a stirring and cold extraction preparation method of coffee liquid. The stirring and cold extraction preparation method of the coffee liquid comprises the following steps: grinding coffee beans into powder to obtain coffee powder; mixing the coffee powder with water, stirring and extracting, and filtering to obtain the coffee liquid. The preparation method is simple, and industrial large-scale production is easy; the coffee liquid prepared by the method disclosed by the invention is high in content of nutritional ingredients such as total sugar, polyphenol and flavone, good in flavor and taste, and easier to accept by consumers.

Description

Technical Field

[0001] The present invention relates to the technical field of coffee liquid preparation, and in particular to a method for preparing coffee liquid by stirring and cold extraction. Background Art

[0002] At present, the coffee liquid prepared by the cold extraction method in the existing technology generally has the problem of uneven extraction, and the organic components in the coffee liquid, such as total sugar, polyphenols, flavonoids and other nutrients, are low in content, which affects the flavor and mouthfeel of the coffee liquid. Therefore, a stirring cold extraction method for preparing coffee liquid is provided to improve the organic components, flavor and mouthfeel of the coffee liquid, which is of great significance to the technical field of coffee liquid preparation. Summary of the Invention

[0003] Based on the above content, the present invention provides a method for preparing coffee liquid by stirring and cold extraction.

[0004] To achieve the above object, the present invention provides the following solutions:

[0005] The present invention provides a method for preparing coffee liquid by stirring and cold extraction, comprising the following steps:

[0006] Grind coffee beans into powder to obtain coffee powder;

[0007] The coffee powder and water are mixed, stirred and extracted, and then filtered to obtain the coffee liquid.

[0008] In a preferred embodiment of the present invention, the particle size of the coffee powder is 800 μm.

[0009] In a preferred embodiment of the present invention, the material-liquid ratio of the coffee beans to the water is 1 g:12 mL.

[0010] In a preferred embodiment of the present invention, the stirring speed of the stirring extraction is 7000 rpm.

[0011] In a preferred embodiment of the present invention, the temperature of the stirring extraction is 4°C.

[0012] In a preferred embodiment of the present invention, the stirring extraction time is 5 hours.

[0013] In a preferred embodiment of the present invention, the pore size of the filtration mesh is 20 μm.

[0014] The present invention discloses the following technical effects:

[0015] The preparation method of the present invention is simple and easy to industrialize and mass-produce; the coffee liquid prepared by the method of the present invention has high content of nutrients such as total sugar, polyphenols, and flavonoids, and has good flavor and taste, and is more easily accepted by consumers. DETAILED DESCRIPTION

[0016] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as limiting the present invention, but rather as a more detailed description of certain aspects, features, and embodiments of the present invention.

[0017] It should be understood that the terms described herein are intended only to describe particular embodiments and are not intended to limit the present invention. In addition, for numerical ranges herein, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. The intermediate value within any stated value or stated range, and each smaller range between any other stated value or intermediate value within the stated range, is also encompassed within the present invention. The upper and lower limits of these smaller ranges may be independently included or excluded within the scope.

[0018] Unless otherwise indicated, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art. Although only preferred methods and materials are described herein, any methods and materials similar or equivalent to those described herein may also be used in the practice or testing of the present invention. All documents mentioned in this specification are incorporated by reference to disclose and describe the methods and / or materials associated with the documents. In the event of any conflict with any incorporated document, the contents of this specification shall prevail.

[0019] It will be apparent to those skilled in the art that various modifications and variations may be made to the specific embodiments described herein without departing from the scope or spirit of the invention. Other embodiments will be apparent to those skilled in the art from the description of the invention. The description and examples are intended to be exemplary only.

[0020] The words “include,” “including,” “have,” “contain,” etc. used in this document are open-ended terms, meaning including but not limited to.

[0021] The present invention provides a method for preparing coffee liquid by stirring and cold extraction, comprising the following steps:

[0022] Grind coffee beans into powder to obtain coffee powder;

[0023] The coffee powder and water are mixed, stirred and extracted, and then filtered to obtain the coffee liquid.

[0024] In a preferred embodiment of the present invention, the particle size of the coffee powder is 800 μm.

[0025] In a preferred embodiment of the present invention, the material-liquid ratio of the coffee beans to the water is 1 g:12 mL.

[0026] In a preferred embodiment of the present invention, the stirring speed of the stirring extraction is 7000 rpm.

[0027] In a preferred embodiment of the present invention, the temperature of the stirring extraction is 4°C.

[0028] In a preferred embodiment of the present invention, the stirring extraction time is 5 hours.

[0029] In a preferred embodiment of the present invention, the pore size of the filtration mesh is 20 μm.

[0030] Unless otherwise specified, the technical solutions described in the present invention are all conventional solutions in the field, and the reagents or raw materials used, unless otherwise specified, are purchased from commercial channels or have been disclosed.

[0031] The technical solutions provided by the present invention are described in detail below with reference to the embodiments, but they should not be construed as limiting the scope of protection of the present invention.

[0032] Example 1

[0033] According to the material-liquid ratio of 1:12 (g / mL), 20 g of coffee beans and 240 mL of 4°C Zhenming mineral water were weighed, and the coffee beans were ground into powder with a fineness of 1.5 (particle size of 800 μm). The coffee powder and water were placed in a stirring cup, stirred and extracted at 4°C (stirring speed of 7000 rpm) for 5 hours, and then filtered (filter pore size of 20 μm) to obtain coffee liquid.

[0034] The coffee beans used in Example 1 were Daydream, Opening Note, and Natural Awakening (Daydream, Opening Note, and Natural Awakening were purchased from Yunnan Unknown Philosophy Technology Co., Ltd., respectively). The coffee liquids prepared from different coffee beans were labeled Daydream, Opening Note, and Natural Awakening respectively; the total acid, total sugar, polyphenols, flavonoids, starch, soluble solids, caffeine, chlorogenic acid, trigonelline, protein, fat, amino acids, organic acids, and monosaccharide contents of Daydream, Opening Note, and Natural Awakening coffee liquids were detected (the test method refers to GB12456-2021, GB / T 15672-2009, GB / T 44349-2024, GB / T 20574-2006, GB 5009.9-2016, GB / T 12143-2008, GB 5009.139-2014, GB 5009.5-2025, GB The results are shown in Table 1. The taste of Daydream, Opening Notes, and Natural Awakening coffee liquids was tested using an electronic tongue, and the results are shown in Table 2. The color difference of Daydream, Opening Notes, and Natural Awakening coffee liquids was tested (using a colorimeter), and the results are shown in Table 3.

[0035] Table 1

[0036] Daydreaming Opening remarks Wake up naturally Total acid (g / L) 3.58 4.10 3.33 Total sugar (mg / mL) 32.10 38.77 36.26 Polyphenols (mg / mL) 35.868 28.256 23.438 Flavonoids (mg / mL) 84.321 72.970 61.976 Starch (mg / mL) 72.176 69.234 110.181 Soluble solids (%) 1.86 1.97 1.97 Caffeine (mg / mL) 1.271 1.221 1.495 Chlorogenic acid (mg / mL) 1.218 1.383 1.382 Trigonelline (mg / mL) 0.956 0.031 0.031 Protein content (%) 0.11 0.12 0.15 Fat(%) 0.51 0.45 0.58 Amino acids (mg / mL) 0.077 0.510 0.042 Organic acid (mg / mL) 7.76 7.03 7.59 Monosaccharide (mg / mL) 4.71 3.34 2.62

[0037] Table 2

[0038] sour bitterness astringency Umami salty Bitter aftertaste Astringent-Aftertaste Fresh-aftertaste sweetness Daydreaming -1.88 11.54 14.20 14.35 5.32 2.47 3.17 -1.24 0.65 Wake up naturally -1.58 12.09 13.81 14.59 6.00 2.98 3.26 0.00 0.60 Opening remarks 1.41 4.50 1.86 12.95 15.00 1.29 1.50 -5.56 0.86

[0039] Table 3

[0040] L*(D65) a*(D65) b*(D65) ΔE Daydreaming 5.44 5.50 4.87 9.18 Opening remarks 6.00 6.54 5.88 10.65 Wake up naturally 5.12 5.72 4.72 9.02

[0041] Table 1 shows a balance of acidity and flavor. The Opening coffee has the highest total acidity (4.10 g / L), potentially contributing to a brighter acidity, consistent with the results in Table 2. The Natural Awakening coffee has the lowest total acidity (3.33 g / L), resulting in a softer taste, consistent with the low-acidity profile of cold brew coffee. The Natural Awakening coffee has the lowest monosaccharide content (2.62 mg / mL), but significantly higher starch content (110.18 mg / mL), giving the coffee a mellower mouthfeel. Regarding antioxidant and anti-inflammatory properties, Daydream coffee has the highest levels of polyphenols (35.868 mg / mL) and flavonoids (84.321 mg / mL), demonstrating significant antioxidant and anti-inflammatory potential. The Natural Awakening coffee also has the highest caffeine content (1.495 mg / mL), suggesting that stirring accelerates caffeine dissolution. The Daydream coffee also has a higher level of trigonelline (0.956 mg / mL), far exceeding the other two coffees (0.031 mg / mL). Amino acids are important flavor compounds in coffee, with the highest concentration in the pre-brew (0.510 mg / mL) and the lowest in the natural brew (0.042 mg / mL). Stirring improves the extraction efficiency of active ingredients like caffeine and polyphenols.

[0042] Table 2 shows a comparison of sourness and saltiness: Opening's sourness and saltiness are significantly higher than the other two, resulting in a more complex flavor profile. Daydream and Natural Awakening have negative sourness and a weaker sourness. Bitterness and Aftertaste: Natural Awakening has the highest bitterness and bitter-aftertaste, directly related to its high caffeine content (1.495 mg / mL). Daydream is second in bitterness, but has the strongest astringency, due to its high polyphenol content, which imparts a longer-lasting astringency. Opening has the lowest bitterness and a lighter overall taste. Astringency and Umami: Daydream and Natural Awakening have significantly higher astringency than Opening's, related to their polyphenol and flavonoid content. Natural Awakening has slightly higher umami, but a neutral umami-aftertaste. Opening's umami-aftertaste is negative, and the umami-aftertaste is absent in the aftertaste. Sweetness and mouthfeel are balanced, with Opening's sweetness being the highest and its saltiness being prominent, creating a unique sweet and salty flavor. Natural Awakening has the lowest sweetness. To sum up, daydreaming: high astringency and strong bitterness; opening remarks: balanced sour, sweet and salty, low bitterness and astringency; waking up naturally: strong bitterness and mellowness.

[0043] As can be seen from Table 3, in terms of brightness (L*), the brightness of the opening espresso is the highest (L*=6.00) and the color is relatively light; the brightness of the natural awakening is the lowest (L*=5.12) and the color is the darkest. The high starch content makes the liquid more turbid and has stronger light absorption. In terms of red and yellow tones (a, b), the a value and b value of the opening espresso are both the highest, indicating that its color tends to be red and yellow, which is caused by the degree of coffee bean roasting and the caramelization reaction of sugars, which is consistent with its high total sugar and sweet and sour flavor characteristics; the a value and b value of the natural awakening are lower, and the color tends to be dark brown or dark brown. The ΔE value of the opening espresso is the highest (10.65), indicating that its color is the most different from the standard color and the natural awakening ΔE is the lowest. The influence of the stirring process on color enhances the red and yellow tones.

[0044] The embodiments described above are merely descriptions of preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Without departing from the spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by persons skilled in the art should fall within the scope of protection defined by the claims of the present invention.

Claims

1. A method for preparing coffee liquid by stirring cold extraction, characterized in that: The following steps are involved: Grind coffee beans into powder to obtain coffee powder; The coffee powder and water are mixed, stirred and extracted, and then filtered to obtain the coffee liquid.

2. The method for preparing coffee liquid by stirring cold extraction according to claim 1, characterized in that: The particle size of the coffee powder is 800 μm.

3. The method for preparing coffee liquid by stirring cold extraction according to claim 1, characterized in that: The material-liquid ratio of the coffee beans to the water is 1 g:12 mL.

4. The method for preparing coffee liquid by stirring cold extraction according to claim 1, characterized in that: The stirring speed of the stirring extraction is 7000 rpm / min.

5. The method for preparing coffee liquid by stirring cold extraction according to claim 1, characterized in that: The temperature of the stirring extraction was 4°C.

6. The method for preparing coffee liquid by stirring cold extraction according to claim 1, characterized in that: The stirring extraction time is 5 hours.

7. The method for preparing coffee liquid by stirring cold extraction according to claim 1, characterized in that: The pore size of the filter mesh is 20 μm.