CN115336650B - Processing and brewing method of wild grape leaf tea - Google Patents

Abstract

The invention discloses a processing and brewing method of wild grape leaf tea, which comprises the following steps: picking, spreading and airing the raw materials, deactivating enzymes, manually twisting, stir-frying, drying, extracting fragrance, reducing acid at low temperature and brewing leaf tea. The wild grape leaf tea prepared by the invention has the advantages of yellow green tea leaf bottom, loose and multiple hairs, bright orange of tea soup, sweet fruit fragrance, mild, sweet and light astringency; the leaf tea contains water extract more than 31.5%, total phenol content more than 6.6%, amino acid content more than 1.44%, caffeine content less than 6.4%, and flavonoid content more than 6.24%; the invention realizes the utilization of the grape leaf tea with high nutritive value, changes waste into valuable, enriches the market of leaf tea products and meets the demands of people on nutritive tea products.

Description

Processing and brewing method of wild grape leaf tea

Technical Field

The invention relates to the technical field of agriculture, in particular to a processing and brewing method of wild raw grape leaf tea.

Background

Wild grape (Vitis quinquangularis red.) is one species of the eastern population of the grape subgenera (Euvitis) of the family Vitaceae (Vitaceae), is native to China, is the most widely distributed wild species in the eastern population of the grape subgenera in China, and is mainly distributed in 17 provinces of Qinling and Taishan in the south. The grape has the characteristics of good resistance, low sugar, thick skin, more tannins, thick pigment, unique fragrance and the like, and is a superior raw material for brewing red wine; resveratrol in the pericarp and grape seed is the main ingredient of health care and cosmetic raw materials in the world today. Along with development and utilization of the grape fruits, the planting area of the wild grape is continuously amplified; in the production process, the grape is found to generate a large number of side shoots and tender leaves in spring germination and summer management, and the side shoots and tender leaves need to be manually thinned out to ensure the accumulation of fruit nutrition, and most of removed leaves are directly discarded. The research shows that the wild grape leaves and tender tips also contain abundant bioactive components such as isoquercitrin, rutin, quercetin, bai Lilu alcohol and the like, and have various important pharmacological effects and health care functions such as dispelling wind and removing dampness, inducing diuresis and relieving swelling, detoxifying, edema, diarrhea, wind-heat conjunctival congestion, carbuncle, swelling and furuncle and the like. However, in the production process, people often neglect to develop and utilize the nutritional ingredients in grape leaves and young tips, and discard the grape leaves as waste, so that serious waste of resources is caused.

With the improvement of the living standard of people, how to eat health becomes a focus of attention. Based on the functional components contained in the wild grape leaves and the young shoots and the health care function, if the wild grape leaves and the young shoots are made into novel tea products with high nutritive value, the wild grape leaves and the young shoots have wide market prospect. The raw materials of various tea leaves appearing in the market at present mainly comprise plants of the genus tea of the family theaceae, such as green tea, black tea, scented tea and the like. The related grape leaf tea products are developed and utilized by adopting common grape leaves as raw materials, and the tea making process is improved on the basis of the traditional tea making mode. The back of the raw grape leaf is provided with a thick layer of fluff, so that functional components in the raw grape leaf tea are utilized to the greatest extent and sensory evaluation indexes of the raw grape leaf tea are improved, the manufacturing process of the raw grape leaf tea is different from that of common commercial raw grape leaf tea, and however, related reports of manufacturing the raw grape leaf tea by using raw grape leaf and tender tip are not seen in the prior art so far.

Through the above analysis, the problems and defects existing in the prior art are as follows:

(1) At present, most of the excess leaves and young shoots of the grape are directly discarded by farmers, so that large waste of biomass resources is caused.

(2) The existing leaf tea preparation process is not suitable for making the raw grape leaf tea, and no related report of the tea making process by using the young tips and leaves of raw grape is available at present.

Disclosure of Invention

The invention aims to solve the problems and provide a processing and brewing method of wild grape leaf tea.

The invention realizes the above purpose through the following technical scheme:

a processing and brewing method of wild grape leaf tea comprises the following steps:

picking young tips and leaves of the vitis amurensis;

step two, taking collected young tips and leaves of the vitis amurensis back to a processing chamber, spreading out, placing and selecting;

step three, enzyme deactivation in a frying pan;

step four, manually twisting and forming;

step five, stir-frying;

step six, drying and aroma improving;

step seven, reducing acid at low temperature;

step eight, airtight ventilation preservation;

and step nine, brewing leaf tea.

Preferably, the picking time in the first step is from the beginning of five months to the end of six months, the picking part is one bud with two three leaves at the top of the current annual new tip or the side tip of the summer bud of the vitis vinifera, and at the moment, the sensory evaluation of the leaf tea made of the leaf and the tender tip is best, and the content of nutrient substances is rich.

Preferably, the temperature in the processing chamber in the second step is 20 ℃ plus/minus 2 ℃, the spreading thickness is 2-3cm, the spreading is carried out for 2 hours, the process is carried out once every 30 minutes, and impurities and old leaves are removed, so that part of water is evaporated conveniently, and the leaves and tender tips are made soft.

Preferably, the de-enzyming temperature in the third step is 180 ℃, and the de-enzyming time is 60-80s, so that functional components in the leaves and tender tips can be retained to the greatest extent.

Preferably, in the fourth step, the grape leaf strip is manually rolled for 30min until tight-tied grape leaf strip ropes are formed, and the grape leaf strip ropes are off-white, yellow and curled.

Preferably, the pot temperature is 120 ℃ and the frying time is 1h in the fifth step.

Preferably, in the sixth step, the grape leaf strip rope is baked and flavored by using smokeless charcoal made of tea tree branches or tea seed shells, and the baking temperature is kept at 75-80 ℃ for baking for 1h until the grape leaf strip rope is baked.

Preferably, in the step seven, the leaf tea is packaged and sealed, and is put into a refrigeration house with the temperature of 3-4 ℃ for refrigeration for two months.

Preferably, the ratio of leaf tea to water brewed in the step nine is 1:40, water temperature 90 ℃ and brewing for 6min.

The invention has the following advantages:

1. the preparation process solves the problem of resource utilization of wild grape leaves and young shoots, can effectively retain functional components such as phenols, flavonoids and the like in the grape leaves and young shoots for human body absorption and utilization, and has the advantages of yellow green tea leaf bottoms, loose and multiple hairs, orange brightness of tea soup, sweet fruit fragrance, peace, sweet taste, light astringency and better sensory evaluation after the tea leaves are brewed; the tea extract of the chaeto grape leaves exceeds 31.5 percent, the total phenol content exceeds 6.6 percent, the amino acid content exceeds 1.44 percent, the caffeine content is lower than 6.4 percent, the flavonoid content exceeds 6.24 percent, and the bioactive component content is rich, thereby meeting the demands of people on healthy tea products;

2. the manufacturing process is scientific and convenient, the raw materials of the leaf tea are easy to obtain, the production cost is low, the market prospect is wide, the development of the grape industry can be effectively promoted, the income of farmers is improved, and the problems of environmental pollution caused by agricultural wastes and the like are avoided.

Detailed Description

The invention will be further illustrated with reference to specific examples, but the invention is not limited to these examples.

A processing and brewing method of wild grape leaf tea comprises the following steps:

firstly, picking young tips and leaves of the grape with the picking time from the beginning of five months to the end of six months, wherein the picking part is one bud and two three leaves at the top of the current annual young tips or the top of the summer bud auxiliary tips of the grape, and at the moment, the sensory evaluation of the leaf tea made of the leaves and the young tips is best, and the content of nutrient substances is relatively rich;

step two, taking collected young tips and leaves of the erigeron breviscapus back to a processing chamber with the temperature of 20+/-2 ℃, spreading the young tips and leaves for 2-3cm in thickness, spreading the young tips and leaves for 2 hours, lightly turning over the young tips and leaves every 30 minutes, and simultaneously selecting and removing impurities and old leaves so as to facilitate evaporation of part of water, so that the leaves and young tips are soft;

step three, enzyme deactivation is carried out at 180 ℃ for 60-80s, so that functional components in leaves and tender tips can be retained to the greatest extent;

step four, manually twisting for 30min for molding until tight grape leaf strip ropes are formed, and the grape leaf strips are gray, yellow and coiled;

step five, frying at 120 ℃ for 1h;

step six, baking and aroma raising the grape leaf strip rope by using smokeless charcoal made of tea tree branches or tea seed shells, and keeping the baking temperature at 75-80 ℃ for 1h until the grape leaf strip rope is baked;

step seven, bagging and sealing leaf tea, and putting the leaf tea into a refrigeration house with the temperature of 3-4 ℃ for refrigeration for two months to reduce acid;

and step eight, airtight ventilation preservation.

Step nine, preparing the leaf tea according to the proportion of the leaf tea to water of 1:40, water temperature 90 ℃, and can be drunk after being brewed for 6min, wherein the manufactured Mao grape leaf tea has yellow green tea leaf bottom, loose and multiple hairs, bright orange of tea soup, sweet fruit fragrance, mild, sweet and light astringent taste. The water extract exceeds 31.5%, the total phenol content exceeds 6.6%, the amino acid content exceeds 1.44%, the caffeine content is lower than 6.4%, and the flavonoid content exceeds 6.24%.

Test one: the wild grape leaf tea processing technology is subjected to the following screening:

A1. the raw grape leaf tea is prepared by adopting the processing technology of traditional green tea (stir-fired), black tea and green tea, and sensory evaluation is carried out, so that a relatively good tea preparation technology is selected;

green tea process: collecting tender tip leaves of grape, spreading (room temperature 20 ℃ C., 2 h), deactivating enzyme (pot temperature 160 ℃ C.), rolling (manual rolling), stir-frying to dryness (pot temperature 120 ℃ C.), drying to improve fragrance (80 ℃ C., drying; because the water content of wild grape leaves is lower and the leaves are older, the green tea has the law of tender and old leaf killing and tender leaf killing and multiple stewing and less throwing in the green tea enzyme deactivation process.

The black tea process comprises the following steps: collecting tender tip leaves of grape, withering (20deg.C, 12 h), rolling (manual rolling), fermenting (29deg.C, 4 h), parching to dryness (120deg.C), oven drying to improve fragrance (80deg.C, oven drying).

The green tea process comprises the following steps: collecting young tip leaves of grapes, spreading (room temperature 20 ℃ for 2 hours), shaking (1 hour, every 10 minutes, every 5 mm), airing (30 minutes), shaking (1 hour, every 10 minutes, every 5 mm), airing (1 hour), kneading, stir-frying (pot temperature 120 ℃) and drying to improve fragrance (80 ℃).

A2. The sensory evaluation of the three processes shows that the sensory evaluation of the grape leaf tea obtained by the processes of green tea and black tea is superior to that of green tea, wherein the combined score of the grape leaf tea is shown in table 1, the green tea process is 80.2, the green tea process is 74.3 and the black tea process is 80.0. The green tea process is slightly higher than the black tea process, and the sourness mainly influences the grading of the mouthfeel of the green tea process, namely the grape leaf tea, but the acids can be converted under proper conditions. And finally, selecting a green tea process and a black tea process for rechecking.

From Table 2, it can be seen that the sourness of the grape leaf tea was substantially converted and the tea soup exhibited a more pronounced sweetness. The green tea and the black tea obtained by processing the grape leaves are basically the same in sensory evaluation, and the green tea process is simpler than the black tea, is beneficial to the preservation of amino acid and other nutrient substances, and more of the nutrient components of the wild grape leaves are preserved, so that the green tea process is superior to the black tea process in sensory evaluation and nutrient substance preservation.

Table 1 results of evaluation of the tea made by three processes

Treatment of

Appearance of the shape

Fragrance of fragrance

Soup color

Mouthfeel of the product

Leaf base

Comprehensive score

Green tea process

Loose and multiple hairs

Floral fragrance

Orange is bright

Mild sweet and astringent taste and slight sour taste

Green brown

80.2

Green tea process

Loose and multiple hairs

Leaf of Folum Ilicis

Orange yellow and bright

The green taste and the sour and astringent taste are light

Brown color

74.3

Black tea process

Loose and multiple hairs

Caramel fragrance

Yellow red bright

Mild and mild, mild and sour taste

Reddish brown

80.0

Table 2 results of evaluating the leaf tea of the raw grape made by the two processes after the low temperature refrigeration

Treatment of

Appearance of the shape

Fragrance of fragrance

Soup color

Mouthfeel of the product

Leaf base

Comprehensive score

Green tea process

Loose and multiple hairs

Floral fragrance

Orange is bright

Mild sweet and astringent taste

Green brown

86.8

Black tea process

Loose and multiple hairs

Caramel fragrance

Yellow red bright

Mild and sweet taste

Reddish brown

85.4

A3. From the comprehensive analysis results, the green tea process is the most suitable for processing wild raw grape leaf tea.

And (2) testing II: optimizing a processing technology of the green tea of the grape;

B1. optimizing the processes of the collecting season (summer and autumn tea and spring tea), the enzyme deactivating temperature (pot temperature 140 ℃,180 ℃ and 220 ℃) and the processing mode (re-kneading, stir-frying, drying and stem removing) of the raw grape leaf according to the green tea processing technology, and obtaining the optimal processing technology of the raw grape leaf tea.

B2. As shown in Table 3, the spring tea was evaluated for the appearance, aroma, color, taste and leaf base by five factors, which were all better than those of the summer and autumn tea. The spring tea is tightly tied and tidy in appearance; the fragrance is obvious; the color of the soup is bright; the taste is good; the leaf bottom is neat and complete. So that the sensory scores of the spring grape leaf tea and the summer Qiu Putao leaf tea are higher than those of the summer autumn tea. As can be seen from Table 4, the wild grape spring tea and the summer and autumn tea water extracts, total phenols, amino acids, caffeine and total flavonoids contained no significant difference, whereas the spring tea contained a significantly higher organic acid content of Yu Xiaqiu tea.

As is clear from Table 5, the higher the deactivation temperature of the green tea, the better the fragrance, the higher the deactivation temperature, the more pronounced the sourness, and the taste of the green tea is kept mild and sweet, which is not affected by the deactivation temperature. From the re-evaluation results of the green tea process in table 2, it is known that the sour taste is converted or lost under the appropriate conditions at the later stage, so that the evaluation score of 84.5 at 180 ℃ and the evaluation score of 82.2 at 220 ℃ higher than the evaluation score of 80.8 at 140 ℃ can be obtained in the above three kinds of evaluation results of the de-enzyming temperatures in table 3. Therefore, the fixation temperature of 220 ℃ and 180 ℃ is slightly better than the fixation temperature of 140 ℃ for the quality of the grape leaf tea. As can be seen from table 6, the water extract content is relatively high at all three fixation temperatures, and is above 30%, and the difference is not significant; with the continuous increase of the fixation temperature, the content of the total phenol gradually decreases, which means that the higher the temperature is in the temperature range, the greater the damage or conversion of the total phenol is. The average content of amino acid does not change with the increment of temperature, which indicates that the temperature has no influence on the content of amino acid in the temperature range; the average content of flavone decreases with increasing temperature; therefore, the comprehensive quality of the raw grape leaf tea at the fixation temperature of 180 ℃ is determined to be optimal.

As can be seen from table 7, the four processing methods were evaluated in terms of the sensory evaluation to obtain a comprehensive score of the four processing methods of grape leaf tea, wherein the total score was 80.0 for re-kneading, 88.5 for drying, 82.0 for parching, and 85.2 for stem removal; as can be seen from Table 8, the flavone content, water extract and total phenol content of the four processing modes are higher; the organic acid and caffeine content in the drying processing mode is relatively low. So the quality of the grape leaf tea processed by the drying mode is good.

TABLE 3 evaluation results of Mao grape She Chuncha and Xia autumn tea

TABLE 4 main active ingredient content of Mao grape She Chuncha, summer and autumn tea

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Table 5 results of green tea evaluation of three fixation temperatures of Vitis vinifera

Treatment of

Appearance of the shape

Fragrance of fragrance

Soup color

Mouthfeel of the product

Leaf base

Comprehensive score

140℃

Loose and multiple hairs

Grass smell, flower fragrance

Orange is bright

Mild sweet, astringent and slightly sour

Green brown

80.8

180℃

Loose and multiple hairs

Floral fragrance

Orange is bright

Mild sweet, astringent and sour

Green brown

84.5

220℃

Loose and multiple hairs

Floral fragrance

Orange is bright

Mild sweet and astringent taste, and sour taste

Green brown

82.2

Table 6 content of nutrient substances in Mao grape leaf tea at three fixation temperatures

Treatment of	Water extract (%)	Total phenol content (%)	Amino acid content (%)	Flavone content (%)
					140℃	31.46±0.367aA	6.87±0.020aA	1.43±0.027aA	6.65±0.026aA
180℃	31.57±0.474aA	6.61±0.086bA	1.44±0.023aA	6.24±0.036bB
					220℃	30.11±0.240aA	6.16±0.031cB	1.44±0.020aA	6.13±0.035cC

Table 7 results of evaluation of four processing methods of grape leaf tea

Table 8 major active ingredient content of four processing modes grape leaf tea

Treatment of

Flavone content (%)

Water extract (%)

Free amino acids (%)

Organic acid (mg/g)

Caffeine (%)

Total phenol content (%)

Re-kneading

6.66±0.03a

31.81±0.06a

1.48±0.04a

16.17±0.03a

6.69±0.15a

6.62±0.09a

Parching to dryness

6.60±0.02b

31.95±0.01b

1.54±0.02a

15.66±0.02b

6.40±0.15ab

6.62±0.21a

Drying

6.64±0.02b

32.12±0.02a

1.54±0.02ab

15.71±0.02bc

6.53±0.09b

6.78±0.12a

Stem removing

6.46±0.01c

32.03±0.04d

1.50±0.02b

15.72±0.03c

6.39±0.05b

6.54±0.25a

B3. The experimental results show that: and (3) preparing the raw grape She Chuncha by a green tea processing technology in a way of deactivating enzymes at 180 ℃ and drying, wherein the raw grape leaf tea is optimal in sensory evaluation and nutrient content.

In summary, the specific preparation process of the grape leaf tea comprises the steps of collecting one bud of two trefoil leaves at the top of the current annual young shoots or the top of the summer bud auxiliary shoots of the grape, spreading for 2 hours at 20 ℃ in a processing room, spreading for 2-3cm in thickness, turning once every 30 minutes, deactivating enzyme for 60-80 seconds in an iron pan at 180 ℃ and manually kneading for 30 minutes until tight grape leaf ropes are formed, turning off the ash white, curling, cooking at 120 ℃ for 1 hour, baking smokeless charcoal made of tea tree trunks or tea seed shells at 75-80 ℃ for 1 hour in a smokeless state, extracting fragrance, storing for two months in a refrigerator at 3-4 ℃ for reducing acid, and keeping tea water proportion of 1:40, soaking for 6min. At the moment, the tea leaf bottom of the Mao grape leaf tea is yellow green, loose and hairy, and the tea soup is bright in orange, sweet in fruit fragrance, mild, sweet and astringent. The water extract exceeds 31.5%, the total phenol content exceeds 6.6%, the amino acid content exceeds 1.44%, the caffeine content is lower than 6.4%, and the flavonoid content exceeds 6.24%.

The foregoing describes specific embodiments of the present invention. It is to be understood that the invention is not limited to the particular embodiments described above, and that various changes and modifications may be made by one skilled in the art within the scope of the claims without affecting the spirit of the invention.

Claims (3)

1. A processing method of wild grape leaf tea is characterized in that: the method comprises the following steps:

picking young tips and leaves of the vitis amurensis;

step two, taking collected young tips and leaves of the eriophyllum inophyllum into a processing chamber, wherein the temperature in the processing chamber is 20+/-2 ℃, spreading and placing thickness is 2-3cm, spreading and placing for 2 hours, lightly turning every 30 minutes, removing impurities and old leaves, and selecting;

step three, enzyme deactivation is carried out in a frying pan, wherein the enzyme deactivation temperature is 180 ℃, and the enzyme deactivation time is 60-80s;

step four, manually twisting and forming, wherein the twisting time is 30min;

step five, stir-frying, wherein the pot temperature is 120 ℃ during stir-frying, and stir-frying is carried out for 1h;

step six, baking and aroma raising the grape leaf strip rope by using smokeless charcoal made of tea tree branches or tea seed shells, and keeping the baking temperature at 75-80 ℃ for 1h until the grape leaf strip rope is baked;

step seven, reducing acid at low temperature: bagging and sealing leaf tea, and refrigerating in a refrigerator at 3-4deg.C for two months;

step eight, airtight ventilation preservation;

and step nine, brewing leaf tea.

2. The method for processing wild grape leaf tea according to claim 1, wherein the method comprises the following steps: the picking time in the first step is from the beginning of five months to the end of six months, and the picking part is one bud with two three leaves at the top end of the current annual new tip or the auxiliary tip of the summer bud of the vitis amurensis.

3. A method of brewing wild grape leaf tea prepared by the method of claim 1, wherein: the ratio of the tea to the water is 1:40, water temperature 90 ℃ and brewing for 6min.