White tea storage regulation and control method

Abstract

The invention discloses a white tea storage regulation and control method which comprises the following steps: putting white tea into a food-grade polyethylene plastic self-sealing bag with the thickness of 16 silks, sealing, putting the self-sealing bag into an aluminum foil bag, sealing, putting the aluminum foil bag into a constant-temperature and constant-humidity incubator, and storing for more than 3 months; the temperature of the constant-temperature and constant-humidity incubator is 25 DEG C, and the humidity is 50%. According to the white tea storage regulation and control method provided by the invention, the white tea is stored for more than 3 months in combination with multi-layer sealed packaging under the condition of constant temperature (25 DEG C) and constant humidity (50%), so that the variation amplitude of the water content of the white tea can be effectively controlled, and some beneficial components in the white tea are greatly increased or reduced, thereby ensuring the drinking safety; the quality of the white tea is converted and improved, and an ideal flavor effect is finally achieved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of tea storage and circulation, in particular to a white tea storage and regulation method. BACKGROUND

[0002] White tea is one of the six tea types, and its manufacturing process is unique, that is, it is not fried or kneaded, and the color of the finished tea is silver and green, and the surface is covered with white hairs, hence the name "white tea". Fujian is the main producing area of white tea, mainly concentrated in Fuding, Songxi, Jianyang and other places. According to different picking standards, it is divided into baimiao silver needle, baimudan, gongmei and shoumei, etc. Generally, the main purpose of tea storage is to reduce the change of its internal biochemical components, so as to maintain the original flavor of the tea, such as green tea and black tea. However, for some tea types, such as white tea and black tea, the biochemical components are transformed to change the aroma and taste, so as to change the quality of the tea.

[0003] White tea is known as "one-year tea, three-year medicine, seven-year treasure". The taste and quality of white tea are determined by the types, content, composition and ratio of chemical factors such as water extract, tea polyphenol, amino acid, caffeine and soluble sugar in tea soup. Improper storage will cause the water content in white tea to be too high, the microorganism to exceed the standard, and the sensory fission to be abnormal, etc. Scientific storage conditions are beneficial to the transformation of the compounds in white tea, thereby positively affecting the flavor and quality of the tea. SUMMARY

[0004] The technical problem to be solved by the present application is to provide a white tea storage and regulation method, which can realize the transformation and improvement of the quality of white tea and achieve the desired flavor effect.

[0005] To solve the above technical problems, the present application discloses a white tea storage and regulation method, which comprises the following steps:

[0006] The white tea is sealed in a food-grade polyethylene plastic self-sealing bag with a thickness of 16 silk, and then the self-sealing bag is placed in an aluminum foil bag. After sealing, it is placed in a constant temperature and humidity incubator for storage for more than 3 months; the temperature of the constant temperature and humidity incubator is 25℃, and the humidity is 50%. The age of the white tea is generally not more than 10 years.

[0007] Further, during the storage process, the change range of the water content of the white tea is controlled within ±20% of the initial water content, which is beneficial to the transformation and improvement of the quality of the white tea.

[0008] Further, the content of tea polyphenol in the white tea after storage decreases by 0.23-11.35%.

[0009] Further, the content of flavonoids in the white tea after storage increases by 23.4-163.3%.

[0010] Further, the free amino acid content of the white tea increases by 3.69-29.16% after storage.

[0011] Further, the thearubigin and theabrownin content of the white tea increases by 37.66-107.67% and 5.22-42.34% respectively after storage.

[0012] The white tea storage regulation method provided by the present application can effectively control the change range of the water content of the white tea, and make some beneficial components in the white tea greatly increase or reduce the decrease range, thereby ensuring the drinking safety, realizing the transformation and improvement of the quality of the white tea, and finally achieving the ideal flavor effect. BRIEF DESCRIPTION OF DRAWINGS

[0013] Figure 1 is a tea polyphenol content diagram of different white tea samples;

[0014] Figure 2 is a flavone content diagram of different white tea samples;

[0015] Figure 3 is a free amino acid content of different white tea samples;

[0016] Figure 4 is a soluble sugar content diagram of different white tea samples;

[0017] Figure 5 is a thearubigin content diagram of different white tea samples;

[0018] Figure 6 is a theabrownin content diagram of different white tea samples;

[0019] Figure 7 is a EGCG content diagram of different white tea samples;

[0020] Figure 8 is a ECG content diagram of different white tea samples;

[0021] Figure 9 is a EGC content diagram of different white tea samples;

[0022] Figure 10 is a EC content diagram of different white tea samples;

[0023] Figure 11 is a water content diagram of different white tea samples;

[0024] Figure 12 is a gallic acid content diagram of different white tea samples;

[0025] Figure 13 is a caffeine content diagram of different white tea samples. Detailed Implementation

[0026] The present invention will be further explained below with reference to the embodiments. The following embodiments are for illustrative purposes only and are not intended to limit the scope of the invention.

[0027] This invention investigated the sealed storage of 15 different types of white tea samples, including two different varieties of Grade 1 White Peony, labeled WH and WE respectively, as well as Shoumei loose tea and Shoumei cake tea made from the same batch of raw materials, both labeled WE. The specific sample list is shown in Table 1.

[0028] The above 15 white tea samples were stored for 6 months under the following three specific storage conditions:

[0029] (1) Natural temperature (temperature range of 8.5~37℃), humidity 50%;

[0030] (2) Temperature 25℃, humidity 50%;

[0031] (3) Natural temperature (temperature range 8.5~37℃) and natural humidity (humidity range 46~84%).

[0032] After storage, the contents of tea polyphenols, flavonoids, free amino acids, soluble sugars, tea pigments, catechins, moisture, gallic acid, caffeine, and microorganisms in each sample were determined according to the following methods.

[0033] The content of tea polyphenols was determined in accordance with GB / T 8313-2018 "Determination Method of Tea Polyphenols and Catechins in Tea".

[0034] The flavonoid content was determined according to the method of Xia Li et al. [Xia Li, Liu Shiquan, Zhou Wenyan. Optimization of extraction method of flavonoids in Fu brick tea [J]. Chemical Industry Management, 2018, (35): 81-83.].

[0035] The determination of free amino acid content was carried out in accordance with GB / 8314-2013 "Determination of Total Free Amino Acid Content in Tea".

[0036] The soluble sugar content was determined according to the method of Liang Yanni et al. [Liang Yanni. Microwave-assisted extraction process of soluble sugars from Liubao tea using response surface methodology [J]. Food Industry, 2019, 40(06):34-37.].

[0037] The content of tea pigments was determined according to the method of Bai Jian et al. [Bai Jian, Gong Jiashun, Ai Guangyi, et al. Analysis of components of old tea leaves after pruning and optimization of conditions for the preparation of theabrownins using Aspergillus tabbinus [J]. Journal of Chinese Food Science, 2023, 23(07):250-258.].

[0038] Determination of catechin, gallic acid, caffeine content, refer to GB / T 8313-2018 "Determination of tea polyphenols and catechins in tea" for determination.

[0039] Determination of microbial content, refer to GB 4789.2-2022 "National food safety standard Food microbiological examination Determination of total number of colonies", GB 4789.15-2016 "National food safety standard Food microbiological examination Mold and yeast count" respectively for determination of total number of colonies, mold and yeast content. According to GB 4789.3-2016 "National food safety standard Food microbiological examination Coliform group count" for determination of coliform group content.

[0040] Table 1 White tea sample list

[0041]

[0042] Example 1 Analysis of changes in white tea polyphenol content under different storage conditions

[0043] Tea polyphenols are a general term for phenolic compounds and their derivatives in tea, composed of more than 30 substances containing phenolic groups, and play an important role in the formation of color, aroma and flavor of tea. The changes in tea polyphenol content of 15 white tea samples are as shown in Table 1. Figure 1

[0044] The initial tea polyphenol content of the 15 white tea samples was between 15.40% and 17.07%, which was consistent with the general white tea polyphenol content determination interval. After 6 months of storage under natural temperature and humidity of 50%, the tea polyphenol content of the 15 white tea samples was 14.59% to 17.06%; after 6 months of storage under natural temperature and natural humidity, the tea polyphenol content of the 15 white tea samples was 14.49% to 16.22%; after 6 months of storage under temperature 25℃ and humidity 50%, the tea polyphenol content of the 15 white tea samples was 14.1% to 17.06%. Under the three storage conditions, the tea polyphenol content of WH Bai Muban and WX Bai Muban of different years all showed a trend of first increasing and then decreasing with increasing storage time, and the tea polyphenol content of WE Shoumei loose tea and Shoumei cake tea also showed a trend of first increasing and then decreasing. Overall, under natural temperature and natural humidity, the absolute content of tea polyphenols decreased by 1.78% to 18.80%, and under temperature 25℃ and humidity 50%, the absolute content of tea polyphenols decreased by 0.23% to 11.35%.

[0045] Example 2 Analysis of changes in white tea flavonoid content under different storage conditions

[0046] ​Flavonoids in tea are one of the important taste substances in tea, and flavonoids have good antioxidant effect. The flavonoid content of 15 white tea samples is shown in Table 1. Figure 2

[0047] The initial flavonoid content of 15 white tea samples is between 2.48% and 3.85%. After being stored for 6 months under natural temperature and 50% humidity, the flavonoid content of 15 white tea samples is between 5.18% and 6.75%; after being stored for 6 months under natural temperature and natural humidity, the flavonoid content of 15 white tea samples is between 4.39% and 6.60%; after being stored for 6 months under 25°C and 50% humidity, the flavonoid content of 15 white tea samples is between 4.75% and 6.53%. Under the three storage conditions, the flavonoid content of WH Bai Mudan, WX Bai Mudan, WE Shoumei loose tea and Shoumei cake tea of different years all shows a trend of first increasing and then decreasing with the increase of storage time. Under 25°C and 50% humidity, the flavonoid content of Bai Mudan samples has the largest increase of 104.12% to 154.46%, and under natural temperature and 50% humidity, the absolute flavonoid content of Shoumei samples has a larger increase of 45.94% to 105.43%.

[0048] Example 3 Analysis of the content of free amino acids in white tea of different years under different storage conditions

[0049] The content of free amino acids has a significant influence on the quality of tea and has a greater influence on the fresh taste substances of white tea, and plays an important role in the taste and aroma of tea soup. The content of free amino acids in 15 white tea samples is shown in Table 2. Figure 3

[0050] The initial content of free amino acids in 15 white tea samples is between 2.31% and 3.90%. After being stored for 6 months under natural temperature and 50% humidity, the content of free amino acids in 15 white tea samples is between 2.46% and 3.75%; after being stored for 6 months under natural temperature and natural humidity, the content of free amino acids in 15 white tea samples is between 2.21% and 3.42%; after being stored for 6 months under 25°C and 50% humidity, the content of free amino acids in 15 white tea samples is between 2.59% and 4.32%. Under the three storage conditions, the content of free amino acids in WH Bai Mudan, WX Bai Mudan, WE Shoumei loose tea and Shoumei cake tea of different years all shows a trend of first decreasing and then increasing with the increase of storage time. Under 25°C and 50% humidity, the absolute content of free amino acids in 15 white tea samples has a larger increase of 3.69% to 29.16%, and under natural temperature and 50% humidity, the absolute content of free amino acids in 15 white tea samples has a larger decrease of 0.25% to 14.65%.

[0051] Example 4 Analysis of the change of the content of soluble sugar in white tea of different years under different storage conditions​​

[0052] Soluble sugar in tea is the main taste substance of tea soup, which gives tea soup a sweet and mellow taste. The changes in the content of soluble sugar in the 15 white tea samples are shown in Table 1. Figure 4

[0053] The initial content of soluble sugar in the 15 white tea samples was between 2.05% and 4.18%. After being stored for 6 months under natural temperature and humidity of 50%, the content of soluble sugar in the 15 white tea samples was between 2.21% and 4.33%; after being stored for 6 months under natural temperature and natural humidity, the content of soluble sugar in the 15 white tea samples was between 2.11% and 4.37%; and after being stored for 6 months under temperature of 25°C and humidity of 50%, the content of soluble sugar in the 15 white tea samples was between 1.92% and 4.35%.

[0054] Under natural temperature and natural humidity, the absolute content of soluble sugar in WX Bai Muyan of different years all decreased, with a decrease of 15.36% to 42.98%, and under temperature of 25°C and humidity of 50%, the decrease was 0.56% to 38.07%. Under natural temperature and natural humidity, the absolute content of soluble sugar in WE Shoubie cake tea all increased, with an increase of 8.30% to 15.37%, and under temperature of 25°C and humidity of 50%, the increase was 2.90% to 17.21%. Sugar substances have an important influence on the quality of tea and are the main substances for forming the sweet and mellow taste of tea soup, and indirectly affect the aroma of tea. With the increase of storage time, the increase of the content of soluble sugar helps to improve the quality and flavor of white tea.

[0055] Example 5 Analysis of the changes in the content of tea pigments and catechins in white tea of different years under different storage conditions

[0056] The changes in the content of tea pigments in the 15 white tea samples are shown in Table 2. Figure 5 Figure 6

[0057] ​​​The initial contents of theaflavins and theabrownines of the 15 white tea samples were between 0.83% and 1.83% and between 1.10% and 2.04% respectively. After being stored for 6 months under natural temperature and humidity of 50%, the contents of theaflavins and theabrownines of the 15 white tea samples were between 1.87% and 2.99% and between 1.41% and 2.40% respectively; after being stored for 6 months under natural temperature and natural humidity, the contents of theaflavins and theabrownines of the 15 white tea samples were between 1.64% and 2.99% and between 1.38% and 2.43% respectively; after being stored for 6 months under temperature of 25°C and humidity of 50%, the contents of theaflavins and theabrownines of the 15 white tea samples were between 1.55% and 2.51% and between 1.15% and 2.50% respectively. During the 6 months of storage, the contents of theaflavins and theabrownines of WH Bai Muyan, WX Bai Muyan, WE Shoumei Scattered Tea and Shoumei Cake Tea of different years basically showed an upward trend with the increase of storage time under the three storage conditions.

[0058] After being stored for 6 months under natural temperature and natural humidity, the absolute contents of theaflavins of the 15 white tea samples increased by 66.63% to 132.58%, and the absolute contents of theabrownines increased by 7.77% to 61.25%; after being stored for 6 months under natural temperature and humidity of 50% and under temperature of 25°C and humidity of 50%, the contents of theaflavins and theabrownines of the 15 white tea samples increased by 28.38% to 123.67% and 37.66% to 107.67% respectively, and the contents of theabrownines increased by 11.95% to 37.86% and 5.22% to 42.34% respectively.

[0059] Catechins are a class of compounds with bitter and astringent taste attributes in tea. Among them, ester-type catechins include EGCG and ECG, and simple catechins include EGC and EC. The changes in the contents of catechins of the 15 white tea samples are shown in Table 2. Figures 7 to 10

[0060] The initial contents of EGCG, ECG, EGC and EC of the 15 white tea samples were 4.76% to 6.87%, 1.41% to 1.96%, 1.29% to 1.68% and 0.55% to 1.02% respectively.

[0061] ​The EGCG content of 15 white tea samples stored for 6 months under natural temperature, humidity 50%, natural temperature, natural humidity, and temperature 25℃, humidity 50% conditions was 4.87%-8.35%, 4.50%-6.65%, and 3.57%-6.98% respectively; the ECG content was 1.63%-2.37%, 1.58%-2.18%, and 1.42%-2.18% respectively; the EGC content was 1.34%-2.90%, 1.58%-2.18%, and 1.44%-1.93% respectively; and the EC content was 0.42%-0.76%, 0.41%-2.38%, and 0.42%-0.52% respectively.

[0062] The absolute content of EGCG of WX Bai Muyan and WE Shou Mei scattered tea increased by 2.36%-30.65% under natural temperature, humidity 50% conditions for 6 months, while the absolute content of WX Bai Muyan samples decreased by 2.40%-23.57% under natural temperature, natural humidity conditions, and the absolute content of WE Shou Mei scattered tea and WX Bai Muyan from 2018 to 2022 decreased by 7.17%-36.39% under temperature 25℃, humidity 50% conditions.

[0063] The absolute content of ECG of 15 white tea samples increased by 0.63%-47.24% under natural temperature, humidity 50% conditions for 6 months. The absolute content of ECG of WH Bai Muyan, WX Bai Muyan, and WE Shou Mei cake tea increased by 2.64%-18.44% under natural temperature, natural humidity conditions for 6 months, while the absolute content of ester catechins of WX Bai Muyan from 2018 to 2022 and WE Shou Mei cake tea from 2020 to 2023 decreased by 7.48%-24.75% under temperature 25℃, humidity 50% conditions for 6 months. The degradation of ester catechins helps to reduce the bitterness of white tea.

[0064] The absolute content of EGC of 15 white tea samples increased by 1.01%-123.53% and 4.72%-46.91% under natural temperature, humidity 50% and natural temperature, natural humidity conditions for 6 months, while the absolute content of EGC of 15 white tea samples increased or decreased under temperature 25℃, humidity 50% conditions for 6 months. The absolute content of EC of 15 white tea samples decreased by 9.43%-118.30% and 19.32%-114.35% under natural temperature, humidity 50% and temperature 25℃, humidity 50% conditions for 6 months.

[0065] Example 6 Analysis of moisture content changes of white tea of different years under different storage conditions

[0066] The moisture content changes of 15 white tea samples are as follows Figure 11shown in Table 1.

[0067] The initial moisture content of the 15 white tea samples was between 5.59% and 9.34%. After 6 months of storage under natural temperature and humidity of 50%, the moisture content of the 15 white tea samples was between 6.70% and 8.67%; after 6 months of storage under natural temperature and natural humidity, the moisture content of the 15 white tea samples was between 8.08% and 10.05%; and after 6 months of storage under temperature of 25°C and humidity of 50%, the moisture content of the 15 white tea samples was between 6.53% and 8.75%. Under the three storage conditions, the moisture content of the 15 white tea samples increased by 7.43% to 44.82% under natural temperature and natural humidity. Under natural temperature and humidity of 50% and temperature of 25°C and humidity of 50%, the moisture content of the Bai-mudan sample decreased slightly, and the moisture content of the Shou-mei sample increased slightly. Overall, the moisture content of the white tea was more stable under temperature of 25°C and humidity of 50%, and the white tea was more suitable for long-term storage.

[0068] Example 7 Analysis of changes in the contents of gallic acid and caffeine in the white tea of different years under different storage conditions

[0069] The changes in the contents of gallic acid and caffeine in the 15 white tea samples are shown in Tables 2 and 3. Figure 12 and 13 shown in Table 1.

[0070] The initial content of gallic acid in the 15 white tea samples was between 0.21% and 0.43%, and the content of caffeine was between 3.50% and 5.17%. After 6 months of storage under natural temperature (temperature range: 8.5-37°C) and humidity of 50%, natural temperature (temperature range: 8.5-37°C) and natural humidity (humidity range: 46-84%), and temperature of 25°C and humidity of 50%, the content of gallic acid in the 15 white tea samples was 0.19%-0.44%, 0.21%-0.47%, and 0.15%-0.40%, respectively. After 6 months of storage under temperature of 25°C and humidity of 50%, the absolute content of gallic acid in the 15 white tea samples decreased by 8.06%-48.09%, and the absolute content of gallic acid in the 15 white tea samples increased or decreased under natural temperature (temperature range: 8.5-37°C) and humidity of 50% and natural temperature (temperature range: 8.5-37°C) and natural humidity (humidity range: 46-84%). The results showed that the content of gallic acid increased with the extension of the storage time due to the hydrolysis reaction of gallocatechin and flavonoid glycosides.

[0071] The caffeine content of 15 white tea samples was 3.48% to 6.06%, 2.64% to 5.32%, and 2.78% to 5.35% under natural temperature (temperature range 8.5 to 37℃), humidity 50%, natural temperature (temperature range 8.5 to 37℃), natural humidity (humidity range 46 to 84%), and temperature 25℃, humidity 50% for 6 months. Under the above three specific storage conditions, the caffeine content in Bai Mudan and Shou Mei was relatively stable, with little change. Studies have shown that caffeine has a bitter taste and a low threshold, and interacts with amino acids, theaflavins, and the like. The caffeine content is generally stable, with little change.

[0072] Example 8 Analysis of microbial changes in white tea of different years under different storage conditions

[0073] The changes in the content of total bacterial count, yeast, mold, and E. coli in 15 white tea samples are shown in Tables 2 to 5:

[0074] The initial mold, yeast, E. coli group, and total bacterial count in 15 white tea samples ranged from <10 to 1.0 x 10 2 CFU / g, <10 to 1.5 x 10 2 CFU / g, <3.0 MPN / g, and <10 to 1.4 x 10 4 CFU / g, respectively, indicating good overall microbial conditions. This may be because the withering and drying processes significantly reduced the water content of the white tea samples, making it difficult for most microorganisms to survive and reproduce in a low water activity environment. In addition, the high temperature generated during the drying process also killed some microorganisms, so the number of total bacterial count, yeast, mold, and E. coli in white tea was low at the beginning of storage.

[0075] The 15 white tea samples were stored for 3 and 6 months under the following conditions: 1, natural temperature, natural humidity; 2, natural temperature, humidity 50%; and 3, temperature 25℃, humidity 50%. The content of mold, yeast, E. coli group, and total bacterial count was determined. Due to seasonal changes, the natural temperature and humidity for 3 and 6 months of storage were different: the natural temperature ranged from 10 to 28.8℃ and the natural humidity ranged from 45 to 88% for 3 months of storage; the natural temperature ranged from 8.5 to 37℃ and the natural humidity ranged from 46 to 84% for 6 months of storage.

[0076] The mold content of the 15 white tea samples ranged from <10 to 50 CFU / g and <10 CFU / g after 3 and 6 months of storage under natural temperature and humidity, respectively. The mold content of the 15 white tea samples ranged from <10 to 50 CFU / g and <10 CFU / g after 3 and 6 months of storage under natural temperature and humidity of 50%, respectively. The mold content of the 15 white tea samples ranged from <10 to 1.0 x 10 2 CFU / g and <10 CFU / g after 3 and 6 months of storage under temperature of 25°C and humidity of 50%, respectively. The mold content of the 15 white tea samples fluctuated after 3 months of storage under the above three storage conditions, but the mold content was not detected after 6 months of storage.

[0077] The yeast content of the 15 white tea samples ranged from <10 to 3.18 x 10 2 CFU / g and <10 CFU / g after 3 and 6 months of storage under natural temperature and humidity, respectively. The yeast content of the 15 white tea samples ranged from <10 to 50 CFU / g and <10 to 1.0 x 10 2 CFU / g after 3 and 6 months of storage under natural temperature and humidity of 50%, respectively. The yeast content of the 15 white tea samples ranged from <10 to 50 CFU / g and <10 CFU / g after 3 and 6 months of storage under temperature of 25°C and humidity of 50%, respectively. The yeast content of the 15 white tea samples decreased after 6 months of storage under the above three storage conditions.

[0078] The total number of colonies of the 15 white tea samples ranged from <10 to 1.3 x 10 2 CFU / g and <10 to 50 CFU / g after 3 and 6 months of storage under natural temperature and humidity, respectively. The total number of colonies of the 15 white tea samples ranged from <10 to 1.4 x 10 3 CFU / g and <10 to 50 CFU / g after 3 and 6 months of storage under natural temperature and humidity of 50%, respectively. The total number of colonies of the 15 white tea samples ranged from 25 to 8.0 x 10 4 CFU / g and <10 to 50 CFU / g after 3 and 6 months of storage under temperature of 25°C and humidity of 50%, respectively. The total number of colonies of the 15 white tea samples fluctuated after 3 months of storage under the above three storage conditions, but the total number of colonies decreased to a lower level after 6 months of storage. The coliform bacteria of the 15 white tea samples were not detected (<3.0 MPN / g) after 3 and 6 months of storage under the above three storage conditions.

[0079] From the results, it can be seen that the 15 white tea samples were stored for 6 months under 3 specific storage conditions, and compared with the initial storage, the mold and coliform bacteria were not detected, and the yeast and total bacterial count were reduced to a low level. Studies have shown that when the relative humidity of the storage environment is between 50-70%, and the temperature is around 25-30℃, the microorganisms in tea will start to grow and reproduce using the nutrients in tea, and the total number of bacterial colonies will start to slowly increase. However, when it reaches a certain degree, under good storage conditions, with the passage of time, a dynamic balance will be reached between the chemical composition in tea and the metabolic products of microorganisms, and the activity of microorganisms may gradually decrease, and some microorganisms may even die, and the total number of bacterial colonies may decrease to a certain extent or remain at a low level.

[0080] Table 2 Determination of the total number of bacterial colonies in different white tea samples

[0081]

[0082] Table 3 Determination of the mold content in different white tea samples

[0083]

[0084] Table 4 Determination of the yeast content in different white tea samples

[0085]

[0086] Table 5 Determination of the coliform bacteria content in different white tea samples

[0087]

[0088] Note: A: natural temperature (temperature range 10-28.8℃), natural humidity (humidity range 45-88%); B: natural temperature (temperature range 10-28.8℃), humidity 50%; C: temperature 25℃, humidity 50%; D: natural temperature (temperature range 8.5-37℃), natural humidity (humidity range 46-84%); E: natural temperature (temperature range 8.5-37℃), humidity 50%.

[0089] Of course, the present application can have other various embodiments, and those skilled in the art can make various corresponding changes and modifications according to the present application without departing from the spirit and essence of the present application, but these corresponding changes and modifications should all belong to the protection scope of the claims of the present application.

Claims

1. A white tea storage regulation method, characterized in that, The method comprises the following steps: The white tea is put into a food-grade polyethylene plastic self-sealing bag with a thickness of 16 silk, sealed, and then placed in an aluminum foil bag, sealed, and stored in a constant temperature and humidity incubator for more than 3 months; the temperature of the constant temperature and humidity incubator is 25℃, and the humidity is 50%.

2. The white tea storage regulation method according to claim 1, characterized in that, During the storage process, the change range of the water content of the white tea is controlled within ±20% of the initial water content.

3. The white tea storage regulation method according to claim 1, characterized in that, After the storage, the decrease range of the tea polyphenol content of the white tea is 0.23-11.35%.

4. The white tea storage regulation method according to claim 1, characterized in that, After the storage, the increase range of the flavone content of the white tea is 23.4-163.3%.

5. The white tea storage regulation method according to claim 1, characterized in that, After the storage, the increase range of the free amino acid content of the white tea is 3.69-29.16%.

6. The white tea storage regulation method according to claim 1, characterized in that, After the storage, the increase ranges of the thearubigin and theabrownin contents of the white tea are 37.66-107.67% and 5.22-42.34%, respectively.

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