Preparation method of sweet tea leaf reserve raw material

Abstract

This invention belongs to the field of sweet tea technology, specifically relating to a method for preparing sweet tea leaf reserve raw materials. The invention involves washing away surface dirt with water, followed by steam treatment. The heat serves two purposes: firstly, it eliminates surface microorganisms; secondly, it increases the internal porosity after subsequent air drying. Then, a treatment liquid is applied to encapsulate the interior, preventing the loss of beneficial substances and maintaining internal integrity. Natural preservatives are used for preservation, and high-temperature drying further enhances the encapsulation effect, ensuring the preservation of beneficial substances.

Description

Technical Field

[0001] This invention belongs to the field of sweet tea technology, specifically relating to a method for preparing sweet tea reserve raw materials. Background Technology

[0002] One of the main sources of sweet tea is a deciduous shrub belonging to the genus Rubus in the Rosaceae family. It thrives in warm, humid environments and is commonly found in valleys, hillsides, grasslands, and thickets. The leaves of sweet tea contain catechins, polyphenols, proteins, amino acids, vitamin C, and various minerals. Catechins, in particular, are 300 times sweeter than sucrose and are a low-calorie, non-sugar sweetener that can be used as a sugar substitute. Sweet tea possesses various medicinal properties, including antipyretic and antimalarial effects, weight loss and lipid-lowering effects, inhibition and delay of arteriosclerosis, and prevention of heart disease.

[0003] The benefits of sweet tea also include regulating blood sugar and lipids, quenching thirst, nourishing the liver and kidneys, clearing heat and detoxifying, promoting body fluid production and moistening the lungs, and relieving cough and sore throat. The flavonoids and polyphenols in sweet tea have a protective effect on the liver and kidneys, nourishing them. At the same time, sweet tea is cooling in nature and has the effect of clearing heat and detoxifying, helping to remove heat toxins from the body. Sweet tea has a fragrant aroma and a long-lasting sweet aftertaste, stimulating saliva secretion and quenching thirst. Its lung-moistening function also helps relieve symptoms such as cough and sore throat. In addition, sweet tea can quickly provide energy and relieve fatigue, as its rich content of simple sugars such as sucrose and honey can be quickly absorbed and utilized by the body.

[0004] Currently, the extraction of sweet tea substances requires the use of relatively tender sweet tea leaves. However, there are time restrictions on the harvesting of sweet tea leaves. When storing harvested sweet tea leaves, they are prone to spoilage or loss of beneficial substances. Summary of the Invention

[0005] In view of the shortcomings of the existing technology, the present invention provides a method for preparing sweet tea reserve raw materials that can be used for effective preservation and storage.

[0006] To achieve the above objectives, the technical solution of the present invention is as follows: A method for preparing sweet tea reserve raw material, the method comprising the following steps: (1) Wash the fresh sweet tea leaves, put them in water and stir and soak for 3-5 minutes, then take them out and let them air dry naturally until the moisture content is 60-65% to obtain pretreated sweet tea leaves; (2) Place the pretreated sweet tea leaves in a steamer and steam for 4-7 minutes. Remove, cool naturally, and air dry to obtain primary processed sweet tea leaves. (3) Put the primary processed sweet tea leaves into the processing liquid, stir evenly, let it stand and soak for 1 to 2 hours at 6 to 9℃, take it out, and let it air dry naturally until the moisture content is 50 to 55% to obtain the primary processed sweet tea leaves; (4) Soak the pretreated sweet tea leaves in the preservative solution, take them out, dry them at 60-70℃ until the moisture content is 30-35%, pack them into bags, vacuum them, and you will get the sweet tea reserve raw material.

[0007] In one embodiment, the temperature of the steamer in step (2) is 100-105°C.

[0008] In one embodiment, the treatment solution in step (3) is a mixture of glycerol and a 10% sodium chloride solution by volume ratio of 9:1.

[0009] In one embodiment, the preservative solution in step (4) is a chitosan acetic acid solution with a mass fraction of 3%. Beneficial effects

[0010] This invention removes surface dirt by washing with water, then treats it with steam. The heat can kill surface microorganisms and increase the internal porosity after subsequent air drying. Then, a treatment liquid is used to encapsulate the interior, which can prevent the loss of beneficial substances and maintain the internal integrity. Natural preservatives are used for preservation, and high-temperature drying makes the treatment liquid more effective in encapsulating the interior, ensuring the preservation of beneficial substances. Detailed Implementation

[0011] Unless otherwise specified, all technical terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure pertains. In case of any discrepancy, the definitions in this specification shall prevail.

[0012] Unless otherwise stated, all percentages, portions, proportions, etc. are by weight.

[0013] The terms “comprising,” “including,” “having,” “containing,” “or any other variation thereof” as used herein are intended to cover a non-exclusive inclusion. For example, a composition, process, method, article, or apparatus that comprises a list of elements is not necessarily limited to those elements, but may also include elements not expressly listed or other elements inherent to such composition, process, method, article, or apparatus.

[0014] When quantities, parts by weight, or other numerical values ​​or parameters are given as ranges, preferred ranges, or a series of upper and lower preferred values, it should be understood that they specifically disclose all ranges formed by any pair of values ​​of any larger or preferred range limit and any smaller or preferred range limit, regardless of whether the ranges are disclosed separately. For example, when describing a range of "1 to 5", the described range should be understood to include ranges such as "1 to 4", "1 to 3", "1 to 2", "1 to 2 and 4 to 5", "1 to 3 and 5", etc. Unless otherwise stated, where numerical ranges are described herein, the range is intended to include the range endpoints as well as all integers, fractions, decimals, etc., within that range.

[0015] Furthermore, the indefinite articles “a” and “an” preceding the elements or components of this disclosure are intended to indicate that there is no limitation on the number of times the said element or component appears (i.e., occurs). Therefore, “a” or “an” should be understood to include one or at least one, and unless the quantity is explicitly stated to be singular, the singular form of the said element or component also includes the plural case.

[0016] Unless otherwise specified, the materials, methods, and examples described herein are exemplary and not limiting. While similar or equivalent methods and materials may be used in implementing or testing this disclosure, suitable methods and materials are also described herein.

[0017] This disclosure is described in detail below. Example 1

[0018] The treatment solution is a mixture of glycerol and 10% sodium chloride solution at a volume ratio of 9:1.

[0019] The preservative solution is a 3% (w / w) chitosan-acetic acid solution.

[0020] A method for preparing sweet tea reserve raw material, the method comprising the following steps: (1) Wash the fresh sweet tea leaves, put them in water and stir and soak for 3 minutes, then take them out and let them air dry naturally until the moisture content is 60% to obtain pretreated sweet tea leaves; (2) Place the pretreated sweet tea leaves in a steamer at 100°C for 4 minutes, remove them, let them cool naturally to 30°C, and air dry them to obtain the primary processed sweet tea leaves. (3) Put the primary processed sweet tea leaves into the processing liquid, stir evenly, let it stand and soak for 1 hour at 6℃, take it out, and let it air dry naturally until the moisture content is 50% to obtain the primary processed sweet tea leaves. (4) Soak the pretreated sweet tea leaves in the preservative solution, take them out, dry them at 60°C until the moisture content is 30%, pack them into bags, vacuum them, and you will get the sweet tea reserve raw material. Example 2

[0021] The treatment solution is a mixture of glycerol and 10% sodium chloride solution at a volume ratio of 9:1.

[0022] The preservative solution is a 3% (w / w) chitosan-acetic acid solution.

[0023] A method for preparing sweet tea reserve raw material, the method comprising the following steps: (1) Wash the fresh sweet tea leaves, put them in water and stir and soak for 4 minutes, then take them out and let them air dry naturally until the moisture content is 63% to obtain pretreated sweet tea leaves; (2) Place the pretreated sweet tea leaves in a steamer at 103°C for 5 minutes, remove them, let them cool naturally to 30°C, and air dry them to obtain the primary processed sweet tea leaves. (3) Put the primary processed sweet tea leaves into the processing liquid, stir evenly, let it stand and soak for 1 hour at 8℃, take it out, and let it air dry naturally until the moisture content is 53% to obtain the primary processed sweet tea leaves. (4) Soak the pretreated sweet tea leaves in the preservative solution, take them out, dry them at 65°C until the moisture content is 33%, pack them into bags, vacuum them, and you will get the sweet tea reserve raw material. Example 3

[0024] The treatment solution is a mixture of glycerol and 10% sodium chloride solution at a volume ratio of 9:1.

[0025] The preservative solution is a 3% (w / w) chitosan-acetic acid solution.

[0026] A method for preparing sweet tea reserve raw material, the method comprising the following steps: (1) Wash the fresh sweet tea leaves, put them in water and stir and soak for 5 minutes, then take them out and let them air dry naturally until the moisture content is 65% to obtain pretreated sweet tea leaves; (2) Place the pretreated sweet tea leaves in a steamer at 105°C for 7 minutes, remove them, let them cool naturally to 30°C, and air dry them to obtain the primary processed sweet tea leaves. (3) Put the primary processed sweet tea leaves into the processing liquid, stir evenly, let it stand and soak for 2 hours at 9℃, take it out, and let it air dry naturally until the moisture content is 55% to obtain the primary processed sweet tea leaves; (4) Soak the pretreated sweet tea leaves in the preservative solution, take them out, dry them at 70°C until the moisture content is 35%, pack them into bags, vacuum them, and you will get the sweet tea reserve raw material.

[0027] Comparative Example 1 The treatment solution is glycerol.

[0028] The preservative solution is a 3% (w / w) chitosan-acetic acid solution.

[0029] A method for preparing sweet tea reserve raw material, the method comprising the following steps: (1) Wash the fresh sweet tea leaves, put them in water and stir and soak for 4 minutes, then take them out and let them air dry naturally until the moisture content is 63% to obtain pretreated sweet tea leaves; (2) Place the pretreated sweet tea leaves in a steamer at 103°C for 5 minutes, remove them, let them cool naturally to 30°C, and air dry them to obtain the primary processed sweet tea leaves. (3) Put the primary processed sweet tea leaves into the processing liquid, stir evenly, let it stand and soak for 1 hour at 8℃, take it out, and let it air dry naturally until the moisture content is 53% to obtain the primary processed sweet tea leaves. (4) Soak the pretreated sweet tea leaves in the preservative solution, take them out, dry them at 65°C until the moisture content is 33%, pack them into bags, vacuum them, and you will get the sweet tea reserve raw material.

[0030] Comparative Example 2 The treatment solution is a 10% sodium chloride solution by mass.

[0031] The preservative solution is a 3% (w / w) chitosan-acetic acid solution.

[0032] A method for preparing sweet tea reserve raw material, the method comprising the following steps: (1) Wash the fresh sweet tea leaves, put them in water and stir and soak for 4 minutes, then take them out and let them air dry naturally until the moisture content is 63% to obtain pretreated sweet tea leaves; (2) Place the pretreated sweet tea leaves in a steamer at 103°C for 5 minutes, remove them, let them cool naturally to 30°C, and air dry them to obtain the primary processed sweet tea leaves. (3) Put the primary processed sweet tea leaves into the processing liquid, stir evenly, let it stand and soak for 1 hour at 8℃, take it out, and let it air dry naturally until the moisture content is 53% to obtain the primary processed sweet tea leaves. (4) Soak the pretreated sweet tea leaves in the preservative solution, take them out, dry them at 65°C until the moisture content is 33%, pack them into bags, vacuum them, and you will get the sweet tea reserve raw material.

[0033] Examples 1-3 and Comparative Examples 1-2 were left to stand for 3 months, and then extracted with fresh sweet tea leaves using the same process. The results are shown in the table below: Stevia yield / % Total polyphenol yield of sweet tea / % Example 1 93.6 90.6 Example 2 94.1 91.5 Example 3 92.7 89.7 Comparative Example 1 75.7 69.6 Comparative Example 2 58.9 53.1 Fresh sweet tea leaves 95.6 93.6 The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A method for preparing a reserve raw material of sweet tea leaves, characterized in that, The preparation method includes the following steps: (1) Wash the fresh sweet tea leaves, put them in water and stir and soak for 3-5 minutes, then take them out and let them air dry naturally until the moisture content is 60-65% to obtain pretreated sweet tea leaves; (2) Place the pretreated sweet tea leaves in a steamer and steam for 4-7 minutes. Remove, cool naturally, and air dry to obtain primary processed sweet tea leaves. (3) Put the primary processed sweet tea leaves into the processing liquid, stir evenly, let it stand and soak for 1 to 2 hours at 6 to 9℃, take it out, and let it air dry naturally until the moisture content is 50 to 55% to obtain the primary processed sweet tea leaves; (4) Soak the pretreated sweet tea leaves in the preservative solution, take them out, dry them at 60-70℃ until the moisture content is 30-35%, pack them into bags, vacuum them, and you will get the sweet tea reserve raw material.

2. The method for extracting sweet tea polysaccharides according to claim 1, characterized in that, The temperature of the steamer in step (2) is 100-105℃.

3. The method for extracting sweet tea polysaccharides according to claim 1, characterized in that, The treatment solution in step (3) is a mixture of glycerol and 10% sodium chloride solution at a volume ratio of 9:

1.

4. The method for extracting sweet tea polysaccharides according to claim 1, characterized in that, In step (4), the preservative solution is a 3% chitosan acetic acid solution.