CN101644667A - Quick detector for quality and safety of tea - Google Patents

Abstract

The invention discloses a tea quality and safety rapid detector, which is provided with a casing, and a colorimetric cell cover is arranged on the upper surface of the casing, and is characterized in that a transmission type colorimetric cell is arranged side by side under the colorimetric cell cover of the casing pool and reflective colorimetric cell; the transmissive colorimetric cell is a rectangular tank, one side is provided with a light source/monochromator, and the opposite side is provided with a photodetector; the reflective colorimetric cell is A cuboid with three channel holes in the shape of "a" inside, the channel ports of the channel holes on both sides are respectively equipped with light source/monochromator, the lower channel port of the middle channel hole is equipped with a photoelectric detector, and the upper channel port is equipped with Set up a chromatography plate. The invention can be used for on-site rapid and quantitative detection of heavy metal and pesticide content in tea, and on-site rapid detection of tea quality and safety.

Description

Tea quality and safety rapid detector

technical field

The invention relates to a simple, sensitive and rapid on-site rapid detection instrument for tea quality safety, in particular to a rapid on-site rapid quantitative detection of heavy metal and pesticide content in tea.

Background technique

my country is the origin of tea trees, and tea trees first appeared in the Yunnan-Guizhou Plateau and Xishuangbanna area in southwest my country. The main varieties of tea are green tea, black tea, oolong tea, scented tea, white tea and yellow tea. Tea has the medicinal effect of keeping fit and curing diseases, and it is also full of appreciation, which can cultivate sentiment. Taking tea as a drink has changed people's bad habit of drinking raw water and greatly improved people's health.

After modern scientific separation and identification, tea contains more than 450 kinds of organic chemical components and more than 40 kinds of inorganic mineral elements. The organic chemical components and inorganic mineral elements in tea contain many nutrients and medicinal ingredients. Organic chemical components mainly include: tea polyphenols, catechins, plant alkaloids, proteins, amino acids, vitamins, pectin, organic acids, lipopolysaccharides, sugars, enzymes, pigments, etc. Inorganic mineral elements mainly include: potassium, calcium, magnesium, cobalt, iron, manganese, aluminum, sodium, zinc, copper, nitrogen, phosphorus, fluorine, iodine, selenium, etc.

Among them, catechins: commonly known as tea tannins, are unique components of tea, with bitterness, astringency and astringency. In tea soup, it can be combined with caffeine to alleviate the physiological effects of caffeine on the human body. It has anti-oxidation, anti-mutation, anti-tumor, lower blood cholesterol and low-density lipoprotein content, inhibit blood pressure rise, inhibit platelet aggregation, anti-bacterial, anti-product allergy and other effects. Caffeine, with a bitter taste, is an important component of the taste of tea soup. In black tea soup, it combines with polyphenols to form a compound; after the tea soup is cooled, it forms an emulsification phenomenon. The unique catechins and their oxidized compounds in tea can slow down and continue the excitatory effect of caffeine, so drinking tea can keep people who drive long distances clear-headed and have more endurance.

Tea is rich in 11 kinds of minerals including potassium, calcium, magnesium and manganese. Tea soup contains more cations and less anions, which belongs to alkaline food. It can help maintain body fluids alkaline and keep you healthy.

Potassium: Promote blood sodium excretion. High blood sodium content is one of the causes of high blood pressure. Drinking more tea can prevent high blood pressure.

Fluorine: It has the effect of preventing tooth decay.

Manganese: It has anti-oxidation and anti-aging effects, enhances immune function, and helps calcium utilization. Because it is insoluble in hot water, it can be ground into tea powder for consumption.

Tea is an indispensable drink in people's daily life. In the process of tea production and preservation, people often use pesticides to kill insects. Pesticides contain toxic substances such as organochlorine and organophosphorus, which not only kill pests, but also cause damage to the human body. Therefore, there are extremely strict restrictions on the amount of pesticide residues in tea at home and abroad.

In 1983, my country banned the production of HCH and DDT. However, due to the good insecticidal effect of DDT pesticide, and the dicofol pesticide that has been allowed to be produced in recent years, its oxidation product is DDT pesticide. Generally speaking, the DDT pesticide used in the tea growing process will remain in the field for more than 3 years. Therefore, strictly prohibiting the use of DDT pesticides is an urgent and arduous task in the current tea plantation.

Due to the above reasons, tea quality inspection is very necessary. Ensuring the quality of tea products has become a part of protecting people's health and also one of the foundations for improving the quality of human life. At the same time, the rapid detection technology for detecting the content of heavy metals and pesticides in tea has also received great attention from various relevant departments, and many rapid detection methods have also been included in the standard methods of various countries. At present, there are many instruments and methods for tea quality testing. Such as portable gas chromatography and spectrophotometry, etc., but various detection methods have some shortcomings, some detection methods require expensive instruments, some detection methods have low detection accuracy, cumbersome detection methods, time-consuming and laborious, and cannot detect tea on the spot quality. The chromatograph currently used on the market is not only expensive, but also generally not available in grassroots units, so it is extremely inconvenient to detect tea. Therefore, there is an urgent need to study a low-cost and popular tea quality and safety rapid detection instrument, which is not only convenient for detection, but also has high precision, which can reduce or even prevent the occurrence of poisoning incidents.

Contents of the invention

The object of the present invention is to provide a tea quality and safety quick detector which can detect the tea quality simply, quickly, on the spot and quantitatively.

For reaching above-mentioned purpose, concrete content of the present invention is:

A tea quality and safety rapid detector is provided with a casing, and a colorimetric cell cover is arranged on the upper surface of the casing. Colorimetric pool.

Wherein said transmissive cuvette is a cuboid, one end of the side of the transmissive cuvette is provided with a light source/monochromator, and the other end corresponding to the light source/monochromator is provided with a photodetector, and the light source/monochromator Both the light source and the photodetector are arranged on the colorimetric cell shell of the transmission type colorimetric cell; the bottom end of the transmission type colorimetric cell is closed, and a single-channel reaction transmission type ratio is formed by light source/monochromator and photoelectric detector. Color cuvette, put the cuvette in the middle space of the reaction transmission cuvette.

Wherein the reflective colorimetric cell is a cuboid, and the interior of the reflective colorimetric cell is provided with three channel holes, wherein the channel holes on both sides are symmetrically arranged on both sides of the central channel hole at a certain angle, and the channel holes of the channel holes on both sides On both sides of the reflective colorimetric cell 2, the channel opening of the middle channel hole is on the bottom surface of the reflective colorimetric cell, and the other channel port of the three channel holes is a coincident channel port, and the coincident channel port is located on the reflective colorimetric cell. The upper surface of the pool; light sources/monochromators are respectively installed on the channel openings of the channel holes on both sides. On the coincident channel opening, the upper part of the reflective colorimetric cell is provided with an edge at the inner edge of the coincident channel opening. The edge and the focal point are on the same horizontal plane. The detector receives the reflected light signal of the chromatographic plate through the middle optical path channel.

Wherein, there is a chromatographic plate pressing plate on the chromatographic plate.

Wherein the light source/monochromator is a super bright light-emitting diode; the photodetector is a photosensor.

Wherein the transmissive colorimetric cell and the reflective colorimetric cell are made of plastic, and the chromatographic plate is made of materials such as paper, glass, and aluminum foil.

Wherein the colorimetric cell cover placed on the outer surface of the casing is connected to the casing of the main body.

Wherein the cuvette is a standard quartz or glass cuvette.

It is also provided with a liquid crystal display screen and a plurality of buttons, and a power control switch, a power socket and an RS-232 interface are sequentially arranged on the lower right side behind the casing.

The present invention adopts above-mentioned technical scheme, and its effect is:

1. The colorimetric analysis method is adopted, which makes the operation easy and the test results are intuitive.

2. It is suitable for rapid quantitative detection of a single method or multiple methods of samples.

3. It adopts microprocessor control and has the functions of measurement, setting, recording, saving and data processing. Equipped with RS-232/USB interface, online communication with PC, and equipped with functions such as help. high degree of automation.

4. Large-screen liquid crystal display in Chinese, man-machine interactive operation, small size, light weight, easy to use.

The invention can quickly detect the quality and safety of tea, and quickly detect lead, copper, cadmium, mercury, cadmium, arsenic, organochlorine, HCH, DDT, dicofol, organophosphorus, methamidophos, and acephate , Dimethoate, Dichlorvos, Fenitrothion, Quetiafos, Permethrin, Cypermethrin, Deltamethrin, Fenvalerate, Bifenthrin content.

Description of drawings

Figure 1: is a schematic diagram of the external structure of the present invention.

Fig. 2: is the structural schematic diagram of the reflective colorimetric cell 2 of the present invention.

Fig. 3: is the schematic diagram of the structure of the colorimetric cell of the present invention.

Figure 4: is a schematic diagram of the working principle of the present invention.

Detailed ways

Below with regard to the structural composition and the effect that can produce of tea quality and safety quick detector of the present invention, cooperate accompanying drawing to describe in detail as follows with preferred embodiment:

As shown in Figure 1, the tea quality and safety rapid detector of the present invention is provided with casing 1, is provided with liquid crystal display 11, a plurality of buttons 12 and colorimetric cell cover 13 on the upper surface of casing 1, and in casing 1 A power control switch, a power socket and an RS-232 interface (not shown in the figure) are successively arranged on the lower right side of the back.

A transmissive colorimetric cell 3 and a reflective colorimetric cell 2 are arranged side by side under the colorimetric cell cover 13 of the casing 1 .

As shown in Figure 3, wherein said transmissive cuvette 3 is a cuboid, one end of the side of the transmissive cuvette 3 is provided with a light source/monochromator 33, and the other end corresponding to the light source/monochromator 33 is provided with There is a photodetector 32 , and both the light source/monochromator 33 and the photodetector 32 are arranged on the colorimetric cell housing 31 of the transmissive colorimetric cell 3 . The light source/monochromator 33 is a super bright light emitting diode, which is arranged on the side of the color cell housing 31; the photodetector 32 is a photosensor. The bottom end of the transmissive colorimetric cell 3 is closed, and the reaction transmissive cell 3 of a single channel is formed by the light source/monochromator 33 and the photodetector 32. Color dish (not shown in the figure).

As shown in Figure 2, the reflective colorimetric cell 2 is a cuboid, and the reflective colorimetric cell 2 is provided with three channel holes 231, 232 and 233 in the shape of "a", wherein the channel holes 231 and 233 on both sides are respectively Symmetry is arranged on both sides of the central passage hole 232 at a certain angle, and the passage openings of the two side passage holes 231 and 233 are on both sides of the reflective colorimetric cell 2. On the bottom surface of the colorimetric cell 2, another channel port of the three channel holes 231, 232 and 233 is a coincident channel port 234, and the coincident channel port 234 is located on the upper surface of the reflective colorimetric cell 2; Light source/monochromator 27,28 are installed respectively on the channel opening of 233, and the position of light source/monochromator 27,28 is corresponding, forms a certain angle with side, makes the focus of the light path of light source/monochromator 27,28 converge on the reflection The upper part of the type cuvette 2 coincides with the channel opening 234, and an edge 21 is provided at the inner edge of the overlapping channel opening 234. The edge 21 and the focus are on the same horizontal plane, and a chromatography plate 24 is placed on the edge 21. The chromatography plate 24 corresponds to A photodetector 25 is placed at the bottom of the channel hole 232 to receive the reflected light signal of the chromatographic plate 24 through the optical channel 232 . The chromatographic plate 24 is a special product for chromatographic analysis, and will not be described in detail here. On the chromatographic plate 24, there is a chromatographic plate pressing plate 26, which is covered on the chromatographic plate 24 during detection to ensure that the reflective colorimetric cell 2 is protected from light.

Both the transmissive colorimetric cell 3 and the reflective colorimetric cell 2 are made of plastic, and the chromatographic plate 24 can also be made of chromatography paper; the colorimetric cell cover 12 placed on the outer surface of the casing is connected to the main body casing 1 , can be flipped freely, when opened, the cuvette can be taken out freely and placed in the transmissive cuvette 3 or reflective cuvette 2, when the cuvette cover is closed, the cuvette is protected from light. The cuvette is a standard quartz cuvette (or glass cuvette), which will not be described in detail here.

Among the present invention, light source/monochromator 27,28 and light source/monochromator 33 have adopted the super bright light-emitting diode that Nichia and Toyota Corporation of Japan produce, and brightness parameter is more than 1000mcd; Photodetector 25 among the present invention And photodetector 32 in the present embodiment, has adopted the integrated photoelectric sensor that American TI company produces, and model can be TSL201, TSL202, TSL203, TSL204, TSL205, TSL206, TSL207, TSL208, TSL209, TSL220, TSL230, TSL235, TSL245, One of TSL250, TSL251, TSL250, TSL253, TSL254, TSL255, TSL256, TSL257, TSL258, TSL259, TSL260, TSL261, TSL262. Of course, the present invention can also adopt other integrated photoelectric sensors with equivalent efficacy.

As shown in Figure 4, it is a schematic diagram of the working relationship of each component of the present invention, wherein the light source/monochromator 41, the detected sample 42 and the photodetector 43 are connected in parallel with the microprocessor 44, when the power supply 45 is turned on, the quality of the tea leaves of the present invention The safety and rapid detector will have two working states, as follows:

As shown in Fig. 3 and Fig. 4, when selecting transmission type colorimetric cell 3 to work, at first the cuvette (equivalent to 42 in Fig. 4) that test solution is housed is placed in transmission type colorimetric cell 3, then Close colorimetric cell cover 13, open power supply and light source/monochromator 33 (equivalent to 41 in Fig. 4), the light that light source/monochromator 33 sends is passed through cuvette by photodetector 32 (equivalent to 43 in Fig. 4) After receiving, the signal detected by the photodetector 32 is transmitted to the microprocessor 44 , and the microprocessor 44 performs data analysis and outputs the result to the display screen 11 .

As shown in Fig. 2 and Fig. 4, when selecting the reflective colorimetric cell 2 to work, at first the test solution is dropped on the chromatographic plate 24 (equivalent to 42 in Fig. 4), and then the chromatographic plate pressing plate 26 is covered , then close the colorimetric cell cover 13, open the power supply and light source/monochromator 27,28 (equivalent to 41 in Figure 4), the light that light source/monochromator 27,28 sends is refracted to the chromatographic plate through channel holes 231 and 233 24, then passed to the photodetector 25 (equivalent to 43 in Figure 4) by the channel hole 232, the signal detected by the photodetector 25 passed to the microprocessor 44, carried out data analysis by the microprocessor 44 and the result output to the display screen 11.

Of course, the present invention can also communicate online with the PC through the RS-232/USB interface 16, and the analysis results are displayed by the PC. Microprocessor 44 is P51, P52 series that Philips produces, and its main parameter is 12 single-chip microcomputers, internal memory 64K. The microprocessor 44 is used to receive the output signal of the photodetector and perform data processing, and the processed information is displayed by the liquid crystal display 11 . At the same time, the microprocessor 44 can also communicate online with the computer through the RS-232/USB interface, and the data setting, collection, analysis and processing process can be completed by operating the computer, and the processed information can be displayed on the display screen or printer .

The rapid detection instrument for tea quality and safety proposed by the present invention is based on the fact that the tested substance in the sample reacts with the chromogenic agent to generate a colored compound after being extracted and purified, and a colorimetric method established based on the principle that the compound selectively absorbs visible light Analytical instruments.

Claims (8)

1. A tea quality and safety rapid detector is provided with a casing, and a colorimetric cell cover is arranged on the upper surface of the casing, and it is characterized in that a transmission type colorimetric cell is arranged side by side under the colorimetric cell cover of the casing and reflective cuvettes. 2. The rapid tester for tea quality and safety as claimed in claim 1, wherein said transmissive colorimetric cell is a rectangular trough for placing a cuvette, the bottom surface is closed, and the upper surface is open, and its A light source/monochromator is arranged on one side, and a photodetector is arranged on the opposite side, and the light source/monochromator and the photodetector communicate through each other. 3. The rapid detection instrument for tea quality and safety as claimed in claim 1, wherein the reflective colorimetric cell is a cuboid, inside which there are three channel holes in the shape of "a", and the channels of the channel holes on both sides The openings are located on both sides of the reflective colorimetric cell, and are respectively equipped with a light source/monochromator; the channel opening of the middle channel hole is on the bottom surface of the reflective colorimetric cell, and a photoelectric detector is installed; the three channel holes The other channel port is a coincident channel port concentrated on the upper surface of the reflective colorimetric cell, and a chromatography plate is installed. 4. The tea quality and safety rapid tester according to claim 3, characterized in that a chromatography plate pressing plate is arranged on the chromatography plate. 5. The rapid tea quality and safety detector according to claim 2 or 3, wherein the light source/monochromator is a super bright light-emitting diode; the photodetector is a photosensor. 6. The tea quality and safety rapid detector according to claim 5, wherein the transmission colorimetric cell and the reflective colorimetric cell are both made of plastic material, and the chromatographic plate is made of paper, glass or aluminum foil. become. 7. The tea quality and safety rapid detector according to claim 2, wherein the colorimetric cell cover placed on the outer surface of the casing is connected to the casing. 8. The rapid tester for tea quality and safety according to claim 7, wherein the cuvette is a standard quartz or glass cuvette.

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