The invention involves processing technology and equipment of tea, specifically the method and device used for introducing for the conversion of summer and autumn tea concentrate to instant powdered black tea.
Summer-autumn tea, produced in summer and autumn, has a bitter and poor taste, low price with low economic benefits as a result of its higher internal polyphenols content. In modern technology, summer-autumn tea leaves are extracted, concentrated. It is then aerated for oxidation, to produce instant powdered black tea with bright color and special taste.
This method of oxidation has poor uniformity when ventilating oxygen, and has no guarantee that the tea polyphenols of would be uniformly oxidized to achieve homogeneous tea content. This way to oxidation has a poor uniformity when ventilating oxygen, which has no guarantee that the polyphenols of tea oxidation homogeneously, and it is affected by the level of workers, personal feelings and other factors. Thus, it is difficult to ensure the stability of the quality of oxidation product, and lead to some problems of instant black tea, such as low product quality, the instability of the quality and so on, which has become a bottleneck restricting the development of instant black tea.
During the oxidation process of black tea, polyphenols in the tea have enzyme catalyzed oxidation reaction with oxygen, and produce a series of oxidation, polymerization, condensation reactions which generate a colored oxide product, such as theaflavins, thearubigins and theabrownins, along with the other compounds of chemical reaction to form a unique flavor and aromas quality of black tea. The aflavins can affect the brightness and the freshness degrees of the tea; and the thearubigins determines the tea concentration and color. The color changes of the tea directly reflect content changes of theaflavins and thearubigins, thus can be used to judge the degree of oxidation of black tea.
The purpose of the invention is to provide the method and device used for monitoring the oxidation color of summer-autumn tea concentrate during the oxidation process so as to achieve precise monitoring in oxidation process and improve the quality of instant black tea.
In order to achieve the purpose of the patent above mentioned, a kind of intelligent oxygen method that converts summer-autumn tea concentrate to instant powdered black tea is adopted by the technical scheme of the patent and it is comprised of the following steps: S1: installing gas-liquid mixed pipeline circuit and color detection pipeline loop on the summer-autumn tea liquid storage tank; S2: the summer-autumn tea concentrate in the gas-liquid mixed pipeline loop mix with the airflow and then flow along the mentioned gas-liquid mixed pipeline loop back to the summer-autumn tea liquid storage tank; the color on-line detection device of summer-autumn tea concentrate is installed on the mentioned color detection pipeline loop and the summer-autumn tea concentrate in the stated color detection pipeline loop flow back to the summer-autumn tea liquid storage tank after being extracted chromatic value by the stated color on-line detection device; S3: reading the chromatic value of summer-autumn tea concentrate and closing the stated gas-liquid mixed pipeline loop if the chromatic value is in the range of the target color value, otherwise, returning step S2.
In the above scheme, the gas-liquid mixed pipeline loop comprises a length of a spiral pipe, and the stated summer-autumn tea concentrate flow in the spiral pipe at a high speed after mixing with airflows.
In the above scheme, the mentioned color on-line detection device includes flash frequency LED light source, color detection channel, single point silicon detector and control terminal; the color detection channel is on the color pipeline detection circuit, the flash frequency of LED light source and the color detection channel are connected to the single silicon detector, the single point silicon detector is connected to the control terminal.
In the above scheme, the flash frequency LED light source is a hollow sphere with three groups of luminous body inside, and each group of luminous body is composed of three kinds of light sources, red, green and blue, which are in the same ring. The light path of the color detection channel and the single silicon detector passes through the ring center surrounded by luminous body inside the hollow sphere.
In the above scheme, each group of luminous body brightens for 1 ms in accordance with the color of red, green, and blue respectively and repeats once every 1 minutes.
In addition, the invention also provides a device for dissolving oxygen, includes summer-autumn tea concentrate liquid storage tank, which is equipped with gas-liquid mixing pipe loop and color pipeline detection circuit. The diaphragm liquid pumps, which can extract summer-autumn tea concentrate from the liquid storage tank, and diaphragm air pump, which can compress air, are installed on the gas-liquid mixed loop pipe, and the tea concentrates can flow back to the storage tank when it is mixed with air. The color detection pipeline circuit is provided with a micro peristalsis pump, a flow meter and a color detection channel. The two ends of the color detection channel are respectively provided with a flash frequency LED light source and a single point silicon detector.
Further, the gas-liquid mixing pipe loop is also installed with a coiled pipe, and the summer-autumn tea concentrated liquid and air can be pressed into the spiral pipe at a high speed after they mix with each other.
Further, the color detection channel, the flash frequency LED light source and the single point silicon detector are connected by straight fiber.
Further, the outer horizontal direction of the color detection channel is provided with two interface flanges which are used to connect the straight fiber. The interior of the color detection channel is provided with a quartz plate, and the upper and the lower of the quartz plate are respectively provided with a hose interface for connecting the rubber hose; The the outer wall of the color detection channel and the outer wall of the quartz plate are inlaid with two collimator lenses.
Further, the flash frequency LED light source is a hollow sphere with three groups of luminous body inside and each group of luminous bodies is composed of three kinds of light sources, red, green and blue, which are in the same ring. The axis line of straight fiber (10) passes through the ring center surrounded by luminous body inside the hollow sphere.
The patent has some beneficial effects. For one thing, using the special spiral pipe type dissolved oxygen device to make air through tea extracts and to mix them uniformly can make the polyphenols of summer-autumn tea extracts fully oxidized, which can guarantee the quality of instant black tea products uniform and stable. For another thing, using the color detection device based on multi spectral flash frequency LED light transmission technology to detect color changes of summer-autumn tea concentrate in real-time can precisely determine the moderate oxidation time of the concentrate, which can guarantee the quality of instant black tea after oxidation. Polyphenols of tea can be oxidized more uniformly and stably, and it will be more accurate and scientific to grasp moderate oxidative point and to improve product quality.
Diagram: 1 summer-autumn tea liquid storage tank, 2 micro peristalsis pump, 3 color detection channel, 4 single point silicon detector, 5 flash frequency LED light source, 6 control terminal, 7 diaphragm fluid pump, 8 diaphragm air pump, 9 spiral pipe, 10 straight fiber, 11 rubber hose, 12 flow meter, 13 hose interface, 14 quartz plate, 15 collimator lens, 16 interface flange.
The following is the further details of the technical scheme of the invention with drawings and concrete implementation method. The invention has the versatility for oxygen oxidation of summer-autumn tea concentrate, monitoring of color value in the oxidation process, and control of moderate oxidative. The implementation of this case takes summer and autumn green tea (roasted tea) concentrate as the experimental object, and other types of green tea can refer to this example to extract oxidation.
The method and device to dissolve oxygen with spiral pipe is adopted to promote the uniform oxidation of summer-autumn tea concentrate. The color detection device based on multi spectrum flash frequency LED light transmission technology is adopted to monitor color changes of summer-autumn tea concentrate and it will be oxidized moderately when the color meets the qualification. The specific technical solutions are as follows:
As shown in
As shown in
As shown in
At the beginning of dissolving oxygen, micro peristaltic pump 2 extracts summer-autumn tea concentrate from the liquid storage tank 1 and then injects it into color detection channel 3 with liquid flowmeter 12 monitoring liquid flow rate in the pipeline, and finally, summer-autumn tea concentrate flows back to the liquid storage tank 1 through the quartz cuvette in the color detection channel 3. The light emitted by the flash frequency LED light source 5 is illuminated on the colorimetric plate through the straight fiber 10 which is connected with the SMA905 interface flange of the color detection channel 3, and the light through the summer-autumn tea concentrate is received by single point silicon detector 4 whose intensity value in the red, green and blue light represents the color value, R, G and B of summer-autumn tea concentrate, and finally, the R, G and B values are transmitted to the control terminal through the 2.4 GHZ wireless transmission protocol. The RGB color mode is dependence on device and it's linearity of the perception is low which does not conform to the human visual characteristics and is only used for physical device display storage. CIE L * a * b * is the perfect color model to describe all colors that visible to the human eye, and uniform change in the L * a * b * model correspond to the uniform change in color perception, so it is necessary to transform RGB values into the CIE L * a * b * value. The conversion of RGB to L*a*b* CIE must firstly be converted to XYZ three stimulus value, then converted to L*a*b* CIE value, and finally to determine whether to enter the appropriate range of oxidation. The calculation formula is as follows:
X=var_R*0.4124+var_G*0.3576+var_B*0.1805
Y=var_R*0.2126+var_G*0.7152+var_B*0.0722
Z=var_R*0.0193+var_G*0.1192+var_B*0.9505
Above the formula,
CIE-L*=(116*var_Y)−16
CIE-a*=500*(var_X−var_Y)
CIE-b*=200*(var−Y−var_Z)
Above the formula,
The luminous source of the LED light source 3 is arranged to brighten in accordance with the order of L1, L2, and L3, and the integral time is increased as far as possible under the guarantee that the single point silicon detector 4 does not overflow. Each light source is provided to maintain a luminous for 1 ms, and then the next light source is lit, and the lights are turned on once every 1 minute. Spiral pipe 9 is placed in constant temperature water of 25° C. to ensure a constant temperature of summer-autumn tea concentrate.
Number | Date | Country | Kind |
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201510052747.6 | Feb 2015 | CN | national |
Filing Document | Filing Date | Country | Kind |
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PCT/CN2015/077741 | 4/29/2015 | WO | 00 |