CN105076607A - Manufacturing method for vaccinium bracteatum leaf tea - Google Patents

Abstract

The invention relates to a preparation method of black rice leaf tea. The steps are as follows: (1) remove the stalks of fresh black rice leaves, clean them, beat them, make a suspension with distilled water, heat them, add neutral protease, and ultrasonically hydrolyze them. Obtain the enzymatic hydrolyzate of black rice leaves; (2) remove the stalks of fresh black rice leaves, spread them out in the air at room temperature, cut into strips, boil and kill them, then dry them in the shade at room temperature, dry them, and pulverize them to obtain tea powder of black rice leaves; (3) The leaf protein enzymatic hydrolyzate is mixed with black rice leaf tea powder, packaged and sterilized, and the blood pressure-lowering black rice leaf teabag product is obtained. The invention has the advantages of simple process, convenient operation and large-scale production, and the obtained product meets the requirements of functional food. The brewed tea is pale yellow or greenish in color, rich in fragrance, mellow in taste, sweet in aftertaste, and has the effect of reducing blood pressure.

Description

A kind of preparation method of black rice tree leaf tea

technical field

The invention belongs to the field of food industry, and in particular relates to a method for preparing blood pressure-lowering black rice leaf tea.

Background technique

Black rice tree (Vaccinium Bracteratum Thunb.), also known as southern candle, black rice grass, is widely distributed in central and southern China. Along with people's research on the leaves of black rice, it is gradually found that the leaves of black rice are rich in nutrients and bioactive components: the main active ingredients in the leaves of black rice are flavonoids and flavonoid glycosides, alkaloids, polysaccharides, sterols and Amino acids, etc., have the effects of anti-tumor, lowering blood pressure, lowering blood fat, lowering blood sugar and anti-aging. However, the content and activity of flavonoids with antihypertensive effect are relatively low.

The traditional way of eating the black rice tree is to pick the young leaves, dye the glutinous rice and cook it into black rice, or eat its fruit directly or make wine. The research and development of black rice tree products in foreign countries was earlier, and a series of products have been formed at present. For example, Japan has developed black rice tree beverages, canned fruits, fragrant wine, fruit juice, fruit vinegar, etc.; some European countries also use black rice tree extracts to treat eye diseases. The domestic research and development of black rice tree is relatively late, and there are relatively few products, but a series of products have come out in recent years. Related invention patents such as: black rice wine (Chinese invention patent "Method for making glutinous rice wine with black rice", Publication number CN103881869A; "A kind of brewing method of black rice tree fruit wine", public number CN103131586A); Black rice leaf drink (Rao Jiajia, Chen Bingcan. Production technology research of black rice leaf rice milk drink, 2004 (6): 100- 101); black rice tree juice (Chinese invention patent "black rice fruit juice and its preparation process", publication number CN103876236A); black rice black tea (Chinese invention patent "a preparation method of black rice black tea", publication number CN103907712A), Black rice teabag (Chinese invention patent "A method of preparing tea bag with black rice leaves", publication number CN102389015A); hair dye (Chinese invention patent "Black rice plant black hair cream", publication number CN102000017A). In addition, many patents on the development of health-care rice, noodles, and frozen drinks have been authorized. However, these developments are still in the preliminary processing stage. Therefore, it is of great significance to develop the new uses of the leaves of black rice and improve the processing technology of the leaves of black rice for improving the value of the leaves of black rice.

Contents of the invention

Purpose of the invention: The purpose of the present invention is to provide a method for preparing black rice leaf tea. Firstly, the black rice leaf tea powder is obtained through the traditional tea preparation process through processes such as killing, drying, and crushing of black rice leaf tea, and at the same time, ultrasonic waves are used to assist the enzyme The method is used to prepare ACE inhibitory peptides derived from the leaves of Wufan tree leaves, and the tea powder is mixed with the ACE inhibitory peptides derived from the leaves of Wufan trees, and then packaged to prepare teabags. The relevant information has not been reported at home and abroad.

Technical solution: In order to realize the above-mentioned purpose of the invention, the present invention adopts the following technical solutions:

A method for preparing blood pressure-lowering black rice leaves teabags, clean the fresh black rice leaves after removing the stalks, add protease after beating, carry out ultrasonic-assisted enzymolysis, centrifuge after the end of the enzymolysis, and enzymatic hydrolysis product (supernatant) After being concentrated, freeze-dried, the dried enzymatic hydrolysis product is mixed with black rice leaf tea powder, packaged and sterilized, and the blood pressure-lowering black rice leaf teabag is obtained.

Specific steps are as follows:

(1) Preparation of blood pressure-lowering peptide from black rice leaf protein

Remove the stalks of the fresh black rice leaves, clean them, beat them, make a suspension of 5% to 10% (w/v, g/L) with distilled water, heat to 40°C to 50°C, and add 2,500 to 3,500 U of enzyme Add neutral protease per g, stir well, and then ultrasonically assist enzymolysis, the ultrasonic power is 90-120W, and the ultrasonic time is 30-50min, then centrifuge, and the enzymatic hydrolyzate is concentrated and then freeze-dried.

(2) Preparation of black rice leaf tea powder

Remove the stalks of the fresh black rice leaves, spread them at room temperature for 5-7 hours, cut them into 1-3cm wide strips, boil them for 60-90s, dry them in the shade at room temperature, dry them at 50°C-60°C, and crush them.

(3) Preparation of blood pressure-lowering black rice leaf teabag

The black rice leaf protein enzymatic hydrolyzate obtained in step (1) is mixed with the black rice leaf tea powder obtained in step (2) according to the addition amount of 1% to 5% (w/w, g/g), and after mixing evenly, 2g/bag Packing and sterilizing are the blood pressure-lowering black rice leaf teabag product.

The antihypertensive activity of milk fermented by Enterococcus faecalis strained from raw milk [J]. International Dairy Journal, 2006, 16 (1): 61-69. , the ACE inhibitory activity was calculated according to the formula:

I=(A-C)/(A-B)×100%;

In the formula, I-ACE inhibition rate; A-absorbance of the blank group; B-absorbance when no ACE was added to the reaction system; C-absorbance when ACE and samples were present in the reaction system.

Beneficial effect:

(1) In the present invention, the enzymatic hydrolysis method of the leaves of black rice leaves is used in the preparation of health-care black rice leaf teas for the first time, which realizes the diversification of the black rice leaf tea products. Although the single enzymatic hydrolyzate obtained in step (1) is rich in ACE inhibitory peptides derived from black rice tree leaves, its taste and color are far from the product after mixing tea powder, while the tea powder obtained in step (2) lowers blood pressure The effect is about 3 times lower than that of the product in step (1), so the present invention mixes the enzymatic hydrolysis product and tea powder to form a product, taking into account the appearance, taste and health care effect of the product.

(2) The protein content in the leaves of black rice leaves is 3% to 5% (w/w, g/g), which is one of the plant leaves with higher protein content. There is no report on the deep processing of black rice leaf protein. The application of ultrasound in the enzymatic hydrolysis process of step (1) overcomes the difficult hydrolysis problem of the black rice leaf protein due to the presence of pectin, and improves the ACE inhibitory activity of the black rice leaf protein enzymatic hydrolyzate, and its IC ₅₀ value is 0.96-1.97mg/mL .

(3) In addition to the activity of lowering blood pressure, this product retains the unique fragrance and other activities of the leaves of Wufan tree. It is a health tea with multiple biological activities. The color of the tea brewed by this product is light yellow or greenish, with strong fragrance, mellow taste and sweet aftertaste.

Description of drawings

Fig. 1 is the preparation flowchart of blood pressure lowering black rice leaf tea of the present invention.

Detailed ways

The following examples further illustrate the content of the present invention, but should not be construed as limiting the present invention. Without departing from the spirit and essence of the present invention, the modifications and substitutions made to the methods, steps or conditions of the present invention all belong to the scope of the present invention. Unless otherwise specified, the technical means used in the embodiments are conventional means well known to those skilled in the art.

Example 1

(1) Clean up after removing the stalk of fresh black rice leaves, after beating, be made into a suspension of 5% (w/v, g/L) with distilled water, place in the 40kHz ultrasonic washing tank, the water bath temperature is set to 40°C, when the temperature of the water bath reaches the set temperature, at natural pH, add neutral protease (alias serrapeptase, also known as serrapeptase. The English name is: dispase, or neutralproteinase, produced by Bacillus subtilis through deep Extracted after fermentation, it belongs to a kind of endonuclease), stir evenly and turn on the ultrasonic wave, the ultrasonic power is 90W, ultrasonic assisted enzymolysis for 30 minutes and then centrifuged, the enzymatic hydrolyzate is concentrated, freeze-dried, and the enzymatic hydrolysis of the leaf protein of black rice leaf is obtained product, spare

(2) Remove the stalks from fresh black rice leaves, cool them at room temperature for 5 hours, cut them into 1cm-wide strips, boil them for 60 seconds, dry them in the shade at room temperature (10 hours), dry them at 50°C, and crush them to get black rice leaf tea powder ;

(3) Add 1% (w/w, g/g) of black rice leaf protein enzymatic hydrolyzate to black rice leaf tea powder, mix evenly, pack according to 2g/bag, and sterilize, which is blood pressure lowering black rice leaf bag Bubble tea products. The antihypertensive IC ₅₀ of the water soluble product of this product is 1.97mg/mL. The brewed tea is light yellowish green in color, rich in fragrance, mellow in taste and sweet in aftertaste.

Example 2

(1) Clean up after removing the stalk of fresh black rice leaves, after beating, be made into the suspension of 7.5% (w/v, g/L) with distilled water, place in the 40kHz ultrasonic washing tank, the water bath temperature is set to 45°C, when the temperature of the water bath reaches the set temperature, under the natural pH, add neutral protease according to the enzyme amount of 3000U/g, stir evenly and turn on the ultrasonic wave, the ultrasonic power is 105W, ultrasonic assisted enzymatic hydrolysis for 40 minutes, centrifugation, enzymatic hydrolysis After the product is concentrated, it is freeze-dried to obtain the enzymatic hydrolyzate of the leaf proteolytic product of the black rice tree, which is ready for use;

(2) Remove the stalks from fresh black rice leaves, spread them in the air at room temperature for 6 hours, cut them into 2cm-wide strips, boil them for 75 seconds, dry them in the shade at room temperature (11 hours), dry them at 55°C, and crush them to get black rice leaf tea powder ;

(3) Add 3% (w/w, g/g) of black rice leaf protein enzymatic hydrolyzate to black rice leaf tea powder, mix evenly, pack according to 2g/bag, and sterilize, which is the blood pressure lowering black rice leaf bag Bubble tea products. The antihypertensive IC ₅₀ of the product water soluble is 1.51mg/mL. The brewed tea is light yellowish green in color, rich in fragrance, mellow in taste and sweet in aftertaste.

Example 3

(1) Clean up after removing the stalk of fresh black rice leaves, after beating, be made into a suspension of 10% (w/v, g/L) with distilled water, place in the 40kHz ultrasonic washing tank, the water bath temperature is set to 50°C, when the temperature of the water bath reaches the set temperature, at natural pH, add neutral protease according to the enzyme amount of 3500U/g, stir evenly and turn on the ultrasonic wave, the ultrasonic power is 120W, ultrasonic assisted enzymatic hydrolysis for 50 minutes, centrifugation, enzymatic hydrolysis After the product is concentrated, it is freeze-dried to obtain the enzymatic hydrolyzate of the leaf proteolytic product of the black rice tree, which is ready for use;

(2) Remove the stalks from fresh black rice leaves, cool them at room temperature for 7 hours, cut them into 3cm wide strips, boil them for 90 seconds, dry them in the shade at room temperature (12 hours), dry them at 60°C, and crush them to get black rice leaf tea powder ;

(3) Add 5% (w/w, g/g) of black rice leaf protein enzymatic hydrolyzate to black rice leaf tea powder, mix evenly, pack according to 2g/bag, and sterilize, which is blood pressure lowering black rice leaf bag Bubble tea products. The antihypertensive IC ₅₀ of the product water soluble is 0.96mg/mL. The brewed tea is light yellowish green in color, rich in fragrance, mellow in taste and sweet in aftertaste.

Claims (5)

1. a preparation method of black rice leaf tea, characterized in that, the steps are as follows: (1) Preparation of black rice leaf protein hypotensive peptide: Remove the stalks of the fresh black rice leaves, clean them, make a pulp, make a suspension with distilled water, heat to 40°C-50°C, add neutral protease, stir well, and then ultrasonically assist enzymolysis. After concentrating, freeze-dry to obtain the hydrolyzate of the leaf proteolytic product of black rice leaf, and set it aside; (2) Preparation of black rice leaf tea powder: Remove the stalks of the fresh black rice leaves, spread them out at room temperature, cut them into 1-3cm wide strips, boil them to finish, then dry them in the shade at room temperature, dry them, crush them, and set aside; (3) Preparation of blood pressure-lowering black rice leaf teabag Mix the black rice leaf protein enzymatic hydrolyzate obtained in the step (1) with the black rice leaf tea powder obtained in the step (2), and after mixing evenly, pack at 2 g/bag and sterilize, and the blood pressure-lowering black rice leaf teabag is obtained. 2. The preparation method of black rice tree leaf tea according to claim 1, characterized in that in step (2), the drying time at room temperature is 5 to 7 hours, the drying time is 60 to 90 seconds, and the drying temperature is 50°C to 60°C. 3. the preparation method of black rice tree leaf tea according to claim 1, is characterized in that, in step (3), with the addition amount of black rice tree leaf proteolysis product according to 1%～5% (g/g) and step ( 2) The obtained black rice leaf tea powder is mixed. 4. the preparation method of black rice leaf tea according to claim 1 is characterized in that, the concentration of black rice leaf suspension in step (1) is 5%～10% (g/L); Enzyme amount is 2500 ~3500U/g. 5. The method for preparing black rice leaf tea according to claim 1, characterized in that, in step (1), the ultrasonic power is 90-120W, and the ultrasonic time is 30-50min.