KR102523846B1 - A device for quality evaluation and measurement of major components of black tea using near-infrared spectroscopy and a method thereof - Google Patents

Abstract

The present invention discloses an apparatus and method for evaluating the quality of black tea and measuring major components using a near-infrared spectrometer. The apparatus includes a sample component analysis unit that analyzes components of a black tea sample having a certain sample history and outputs an analysis measurement value; a spectrum measurement unit receiving the measured analysis value and measuring an absorption spectrum of the black tea sample using a near-infrared spectrometer and outputting a near-infrared spectroscopic analysis value; A calibration equation for the main components of black tea is calculated by receiving the analysis measurement value and the near-infrared spectroscopy analysis value, and a calibration equation calculation to verify the suitability of the calculated calibration equation with the correlation between the analysis measurement value and the absorption spectrum and verification unit; and a calibration equation application unit for simultaneously measuring individual contents of major components of black tea by receiving the calibration equation selected after the suitability is verified and applying the calibration equation to the near-infrared spectrometer. It is characterized in that it includes. According to the present invention, the quality control of black tea becomes easy and the decision-making for commercialization becomes clear, enabling mass production of high-quality black tea products, and the quality of black tea can be evaluated quickly, simply, and environmentally friendly, thereby cultivating and processing black tea It can contribute to increase the income of farmers.

Description

A device for quality evaluation and measurement of major components of black tea using near-infrared spectroscopy and a method thereof}

The present invention relates to an apparatus and method for evaluating the quality of black tea and measuring its main components, and more particularly, by using a near-infrared spectrometer to simultaneously measure the main components representing the quality characteristics of black tea by individual content, and measuring the absorption spectrum of the black tea sample It relates to an apparatus and method for quality evaluation of black tea and measurement of major components using a near-infrared spectrometer capable of rapid and accurate quality evaluation and quality control of black tea by measurement.

Black tea (紅茶) is a type of tea, and tea is one of the three most popular beverages enjoyed by people around the world along with coffee and cocoa.

Tea is made from tea leaves of the tea tree, and the tea tree is classified into a small leaf species, Camellia sinensis, and a large leaf species, Camellia assamica, in terms of botanical morphology and chemical composition.

In addition, depending on the processing method such as the degree of oxidation and fermentation, these tea leaves are classified into non-fermented green tea, weakly fermented white tea, partially fermented green tea, fully fermented black tea, and post-fermented tea. There are yellow tea and black tea, and they are classified into six major types of tea according to the color of the water in which tea is brewed, and the ingredients that represent the characteristics of the six major types of tea are different.

Recently, production of black tea, a fermented tea, has increased in Boseong, Hadong, and Jeju, which are the main tea producing areas in Korea, and domestic consumption is also increasing. predicted to be

Most of domestic black teas have a golden or orange-red color, and the taste of Boseong black tea is refreshing and has a good balance of sweet, sour, and astringent tastes. It has a refreshing apple scent.

According to the 2018 Ministry of Food and Drug Safety production performance report (including imports), domestic black tea production was 6,470 tons (98 tons of leached tea, 6,372 tons of solid tea) and 3,790 tons (71 tons of leached tea, 3,719 tons of solid tea) in 2016. production increased by 171.2% compared to

In addition, in domestic black tea manufacturing and production sites, the quality of black tea products may vary due to various factors such as the cultivation environment of tea leaves, harvest time, and brewing method, so it is important to uniformly manage the quality of all kinds of tea.

Therefore, in the current situation where production of fully fermented tea, black tea, is expected to continuously increase, in order to apply a technology that uniformly produces quality to a certain standard by blending domestic black tea produced in various qualities in a certain ratio, Korea There is an urgent need for a technology to quickly and accurately evaluate and manage the unique quality of black tea.

Therefore, the present inventors measure the content of major components for quality control of black tea at farmhouses and industries producing and selling black tea, domestic and foreign research institutes conducting research and development, and by accurately analyzing and verifying individual component contents simply and quickly, An apparatus and method for evaluating the quality of black tea and measuring major components using a near-infrared spectrometer, which can be used for quality control required for mass production of high-quality black tea, has been invented.

KR 10-2141154 B1

The purpose of the present invention is to simultaneously measure the main components representing the quality characteristics of black tea by individual content using a near-infrared spectrometer that does not require a pretreatment process and does not use chemicals for rapid and accurate quality evaluation and quality control of black tea. It is an object of the present invention to provide a black tea quality evaluation and major component measuring device using a near-infrared spectrometer capable of calculating and verifying an optimal calibration equation by measuring the absorption spectrum of a sample.

Another object of the present invention is to provide a method for evaluating the quality of black tea and measuring major components using a near-infrared spectrometer to achieve the above object.

In order to achieve the above object, an apparatus for evaluating the quality of black tea and measuring major components using the near-infrared spectrometer of the present invention includes a sample component analysis unit that analyzes components of a black tea sample having a certain sample history and outputs an analysis measurement value; a spectrum measurement unit receiving the measured analysis value and measuring an absorption spectrum of the black tea sample using a near-infrared spectrometer and outputting a near-infrared spectroscopic analysis value; A calibration equation for the main components of black tea is calculated by receiving the analysis measurement value and the near-infrared spectroscopy analysis value, and a calibration equation calculation to verify the suitability of the calculated calibration equation with the correlation between the analysis measurement value and the absorption spectrum and verification unit; and a calibration equation application unit for simultaneously measuring individual contents of major components of black tea by receiving the calibration equation selected after the suitability is verified and applying the calibration equation to the near-infrared spectrometer. It is characterized in that it includes.

In order to achieve the above object, the calibration formula calculation and verification unit of the black tea quality evaluation and main component measuring device using the near infrared spectrometer of the present invention receives the analysis measurement value and the near infrared spectroscopic analysis value, and simultaneously the main components of black tea a calibration equation calculation unit for calculating the plurality of calibration equations for analysis; and a calibration equation verifier for verifying the suitability of each calibration equation by receiving the calculated plurality of calibration equations and cross-verifying the correlation between the analysis measurement value and the absorption spectrum using a content-specific verification spectrum. It is characterized in that it includes.

The constant sample history of the black tea quality evaluation and major component measuring device using the near-infrared spectrometer of the present invention to achieve the above object is characterized in that the black tea production year, harvest time, production area and tea plantation.

The near-infrared spectrometer of the black tea quality evaluation and main component measurement apparatus using the near-infrared spectrometer of the present invention to achieve the above object is characterized by measuring the absorption spectrum in the wavelength range of 400 to 2,500 nm.

The plurality of calibration equations of the black tea quality evaluation and main component measuring device using the near-infrared spectrometer of the present invention to achieve the above object are expressed by the equation Y = a X + b, wherein a is the NIR spectrometer It is characterized in that a slope value, which is a change ratio of the measured analysis value to a change in the predicted value, and b is a bias value.

In order to achieve the above other object, a method for evaluating the quality of black tea and measuring major components using the near-infrared spectrometer of the present invention is (a) a sample component analyzer analyzes components of a black tea sample having a certain sample history and outputs analysis measurement values step; (b) outputting a NIR spectroscopic analysis value by measuring an absorption spectrum of a black tea sample using a NIR spectrometer after receiving the analysis measurement value by a spectrum measuring unit; (c) The calibration equation calculation and verification unit receives the analysis measurement value and the near-infrared spectroscopic analysis value to calculate the calibration equation for the main component of black tea, and the calibration equation calculated by the correlation between the analysis measurement value and the absorption spectrum verifying the goodness of fit of the equation; and (d) simultaneously measuring individual contents of main components of black tea by applying the calibration equation applied by the calibration equation application unit to the near-infrared spectrometer after receiving the calibration equation selected after verifying the suitability. It is characterized in that it includes.

In step (a), the sample component analysis unit measures moisture, ash, and total nitrogen representing the quality characteristics of the black tea sample in step (a). , total amino acids, theanine, reducing sugars, total acidity, vitamin C, polyphenols, tannins and flavonoids are characterized by chemical wet analysis.

In order to achieve the above other object, the quality evaluation and main component measurement method of black tea using the near-infrared spectrometer of the present invention includes the sample component analysis unit for water by atmospheric pressure heating and drying method, ash by direct incineration method, total nitrogen by Kjeldahl analysis method, and total amino acid It is characterized in that the content is measured using the ninhydrin method.

In order to achieve the above other object, the quality evaluation and main component measurement method of black tea using the near-infrared spectrometer of the present invention is a DNS colorimetric method for reducing sugar, an acid-base titration method for total acidity, a tartaric acid colorimetry for tannin, and a polyphenol. is characterized in that the content is measured using the Folin-Denies method.

In order to achieve the above other object, in step (a) of the present invention, the method for evaluating the quality of black tea and measuring the main components using the near-infrared spectrometer of the present invention, the sample component analysis unit for the chromaticity brightness, redness and yellowness of the black tea sample It is characterized in that it is measured using a colorimeter.

In order to achieve the other object, in step (a), the method for evaluating the quality of black tea and measuring major components using the near-infrared spectrometer of the present invention, the sample component analysis unit performs high-performance liquid chromatography on the total catechin and caffeine content of the black tea sample. Characterized in that it is measured using a graphic analysis method.

In the step (c) of the black tea quality evaluation and main component measurement method using the near-infrared spectrometer of the present invention for achieving the other object, the calibration equation calculation unit in the calibration equation calculation and verification unit calculates the analysis measurement value and the Calculating the plurality of calibration equations for simultaneous analysis of major components of black tea by receiving near-infrared spectroscopy analysis values; And the calibration equation verification unit in the calibration equation calculation and verification unit receives the plurality of calibration equations calculated and cross-verifies the correlation between the analysis measurement value and the absorption spectrum using the content-specific verification spectrum to obtain each calibration equation verifying suitability; It is characterized in that it includes.

Details of other embodiments are included in "Specific Contents for Carrying Out the Invention" and the accompanying "Drawings".

Advantages and/or features of the present invention, and methods of achieving them, will become apparent upon reference to the various embodiments described below in detail in conjunction with the accompanying drawings.

However, the present invention is not limited only to the configuration of each embodiment disclosed below, but may also be implemented in various other forms, and each embodiment disclosed herein only makes the disclosure of the present invention complete, and this It is provided to completely inform the scope of the present invention to those skilled in the art to which the invention belongs, and it should be noted that the present invention is only defined by the scope of each claim of the claims.

According to the present invention, by quickly standardizing and grading after quality evaluation of domestically produced black tea, quality control becomes easy and decision-making for commercialization becomes clear, enabling mass production of high-quality black tea products.

In addition, by using near-infrared spectroscopy that does not require a pretreatment process and does not use chemicals, the quality of black tea can be assessed quickly, easily and environmentally friendly, thereby increasing the commercial value and differentiating the quality. can contribute to increasing the income of

In addition, since the content of individual components of black tea can be simultaneously measured using a near-infrared spectrometer, the analysis time is shortened compared to the conventional wet analysis method, and quality control is improved because no harmful chemicals are used. You can overcome difficult problems.

In addition, in the era of the 4th industrial revolution, online inspection can be applied to the quality evaluation of black tea in the future, and big data on quality evaluation and quality control of domestic black tea is built, reducing production costs and black tea with uniform quality. mass production becomes possible.

1 is a block diagram of a black tea quality evaluation and major component measurement apparatus using a near-infrared spectrometer according to an embodiment of the present invention.
2 is a flowchart illustrating overall operations of a method for evaluating quality of black tea and measuring major components using a near-infrared spectrometer according to an embodiment of the present invention.
FIG. 3 is a flowchart for explaining the detailed operation of step S300 of the method for evaluating the quality of black tea and measuring the main components shown in FIG. 2 .
FIG. 4 is a table showing the history of domestic black tea samples by production year, harvest time, production area, and tea plantation used in step (S100) of the black tea quality evaluation and main component measurement method shown in FIG. 2.
FIG. 5 is a table of various statistics of 210 main components of domestic black tea samples, which are targets of a plurality of calibration formulas, calculated in step S300 of the method for evaluating the quality of black tea and measuring the main components shown in FIG. 2.
FIG. 6 is a table of statistics of polyphenols and catechins among a plurality of calibration formulas calculated in step S300 of the method for evaluating the quality of black tea and measuring major components shown in FIG. 2 .
FIG. 7 is a table of statistics of nitrogen compounds among a plurality of calibration formulas calculated in step S300 of the method for evaluating the quality of black tea and measuring major components shown in FIG. 2 .
FIG. 8 is a table of statistics of soluble solids among a plurality of calibration equations calculated in step S300 of the method for evaluating the quality of black tea and measuring major components shown in FIG. 2 .
FIG. 9 is a table of statistics of moisture, ash, total nitrogen, and color among a plurality of calibration equations calculated in step S300 of the method for evaluating the quality of black tea and measuring major components shown in FIG. 2 .
FIG. 10 shows the correlation between the analysis measurement values for the main components of black tea excluding catechins and the predicted value of near-infrared rays among the plurality of calibration equations calculated in step S300 of the method for evaluating the quality of black tea and measuring the main components shown in FIG. is the graph shown.
FIG. 11 is a graph showing a correlation between an analysis measurement value for catechins and an predicted near-infrared ray predicted value among a plurality of calibration equations calculated in step S300 of the method for evaluating quality and measuring major components of black tea shown in FIG. 2 .
FIG. 12 is a graph of the absorption spectrum measured in step S300 of the method for evaluating the quality of black tea and measuring the main components shown in FIG. 2 .
FIG. 13 is a table of relative error ranges calculated by comparing the suitability verified in step S300 of the black tea quality evaluation and main component measurement method shown in FIG. 2 with conventional wet chemical analysis values.

Hereinafter, the preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

Before explaining the present invention in detail, the terms or words used in this specification should not be construed unconditionally in a conventional or dictionary sense, and in order for the inventor of the present invention to explain his/her invention in the best way Concepts of various terms can be appropriately defined and used.

Furthermore, it should be noted that these terms or words should be interpreted as meanings and concepts consistent with the technical idea of the present invention.

That is, the terms used in this specification are only used to describe preferred embodiments of the present invention, and are not intended to specifically limit the contents of the present invention.

It should be noted that these terms are terms defined in consideration of various possibilities of the present invention.

Also, in this specification, a singular expression may include a plurality of expressions unless the context clearly indicates otherwise.

In addition, it should be noted that similarly, even if expressed in a plurality, it may include a singular meaning.

Throughout this specification, when a component is described as "including" another component, it does not exclude any other component, but further includes any other component, unless otherwise stated. It can mean you can do it.

Furthermore, when a component is described as "existing inside or connected to and installed" of another component, this component may be directly connected to or installed in contact with the other component.

In addition, it may be installed at a certain distance, and in the case of being installed at a certain distance, a third component or means for fixing or connecting the corresponding component to another component may exist. .

Meanwhile, it should be noted that the description of the third component or means may be omitted.

On the other hand, when it is described that a certain element is "directly connected" to another element, or is "directly connected", it should be understood that no third element or means exists.

Similarly, other expressions describing the relationship between components, such as "between" and "directly between", or "adjacent to" and "directly adjacent to" have the same meaning. should be interpreted as

In addition, in the present specification, terms such as "one side", "the other side", "one side", "the other side", "first", and "second" refer to one component with respect to another component. It is used to make it clearly distinguishable from the elements.

However, it should be noted that the meaning of a corresponding component is not limitedly used by such a term.

In addition, in this specification, terms related to positions such as “upper”, “lower”, “left”, “right”, etc., if used, are to be understood as indicating relative positions of corresponding components in the drawing.

In addition, unless an absolute location is specified for these locations, these location-related terms should not be understood as referring to an absolute location.

Moreover, in the specification of the present invention, terms such as "~unit", "~group", "module", and "device", if used, mean a unit capable of processing one or more functions or operations.

It should be noted that this may be implemented in hardware or software, or a combination of hardware and software.

In the drawings accompanying this specification, the size, position, coupling relationship, etc. of each component constituting the present invention is partially exaggerated, reduced, or omitted in order to sufficiently clearly convey the spirit of the present invention or for convenience of explanation. may be described, and therefore the proportions or scale may not be exact.

In addition, in the following description of the present invention, a detailed description of a configuration that is determined to unnecessarily obscure the subject matter of the present invention, for example, a known technology including the prior art, may be omitted.

1 is a block diagram of a black tea quality evaluation and major component measurement apparatus using a near-infrared spectrometer according to an embodiment of the present invention, comprising a sample component analysis unit 100, a spectrum measurement unit 200, calibration formula calculation and verification It has a part 300 and a calibration formula application part 400.

The calibration equation calculation and verification unit 300 includes a calibration equation calculation unit 310 and a calibration equation verification unit 320 .

2 is a flowchart illustrating overall operations of a method for evaluating quality of black tea and measuring major components using a near-infrared spectrometer according to an embodiment of the present invention.

FIG. 3 is a flowchart for explaining the detailed operation of step S300 of the method for evaluating the quality of black tea and measuring the main components shown in FIG. 2 .

Referring to FIGS. 1 to 3, the operation of the black tea quality evaluation and main component measurement method using the near-infrared spectrometer according to an embodiment of the present invention will be described schematically as follows.

First, the sample component analyzer 100 analyzes components of a black tea sample having a certain sample history and outputs an analysis measurement value (S100).

The spectrum measurement unit 200 receives the measured analysis value, measures the absorption spectrum of the black tea sample using the near-infrared spectrometer 250, and outputs a near-infrared spectroscopic analysis value (S200).

The calibration equation calculation and verification unit 300 receives the analysis measurement value and the near-infrared spectroscopic analysis value, calculates a plurality of calibration equations for the main components of black tea, and calculates the calibration equation based on the correlation between the analysis measurement value and the absorption spectrum. The suitability of the calculated calibration equation is verified to select the optimal calibration equation (S300).

That is, the calibration equation calculation unit 310 in the calibration equation calculation and verification unit 300 receives the analysis measurement value and the near-infrared spectroscopic analysis value (S310) and calculates a plurality of calibration equations for simultaneous analysis of major components of black tea. Do (S320).

The calibration equation verification unit 320 in the calibration equation calculation and verification unit 300 receives the calculated plurality of calibration equations (S330) and uses the content-specific verification spectrum to correlate the analysis measurement value with the absorption spectrum. By cross-validating (S340), the goodness of fit of each calibration equation is verified (S350).

The calibration equation application unit 400 receives the calibration equation selected after the suitability is verified, and applies the calibration equation to the near-infrared spectrometer 250 to simultaneously measure the individual contents of the main components of black tea (S400).

FIG. 4 is a table showing the history of domestic black tea samples by production year, harvest time, production area, and tea plantation used in step (S100) of the black tea quality evaluation and main component measurement method shown in FIG. 2.

FIG. 5 is a table of various statistics of 210 main components of domestic black tea samples, which are targets of a plurality of calibration formulas, calculated in step S300 of the method for evaluating the quality of black tea and measuring the main components shown in FIG. 2.

FIG. 6 is a table of statistics of polyphenols and catechins among a plurality of calibration formulas calculated in step S300 of the method for evaluating the quality of black tea and measuring major components shown in FIG. 2 .

FIG. 7 is a table of statistics of nitrogen compounds among a plurality of calibration formulas calculated in step S300 of the method for evaluating the quality of black tea and measuring major components shown in FIG. 2 .

FIG. 8 is a table of statistics of soluble solids among a plurality of calibration equations calculated in step S300 of the method for evaluating the quality of black tea and measuring major components shown in FIG. 2 .

FIG. 9 is a table of statistics of moisture, ash, total nitrogen, and color among a plurality of calibration equations calculated in step S300 of the method for evaluating the quality of black tea and measuring major components shown in FIG. 2 .

FIG. 10 shows the correlation between the analysis measurement values for the main components of black tea excluding catechins and the predicted value of near-infrared rays among the plurality of calibration equations calculated in step S300 of the method for evaluating the quality of black tea and measuring the main components shown in FIG. is the graph shown.

FIG. 11 is a graph showing a correlation between an analysis measurement value for catechins and an predicted near-infrared ray predicted value among a plurality of calibration equations calculated in step S300 of the method for evaluating quality and measuring major components of black tea shown in FIG. 2 .

Referring to FIGS. 1 to 11, the organic operation of the black tea quality evaluation and main component measurement method using the near-infrared spectrometer according to an embodiment of the present invention will be described in detail.

In an embodiment of the present invention, spring tea, summer tea, and autumn tea by harvest time of tea leaves are representative of the three regions of Boseong, Hadong, and Jeju, which are the main domestic tea production areas, so that the degree of content of the main components representing the characteristics of Korean black tea is representative. The car was sampled by manufacturing year for 4 years from 2017 to 2020.

In particular, when the year of manufacture was 2020, samples were taken at each stage of the manufacturing process, such as tea leaves, withering, rubbing, fermentation, and drying. Species were collected and spectral absorption spectra were obtained in the wavelength range of 400 to 2,500 nm with 210 near-infrared spectroscopy (NIRS) machines repeated three times and used for the development of a predictive model.

Near-infrared spectra were measured at intervals of 2 nm using a near-infrared spectrophotometer and a diffuser with a depth of 1 mm plated with pure gold in a reflectance vessel made of quartz.

First, as shown in FIG. 4, the sample component analysis unit 100 assigns domestic black tea samples, which are fermented teas by production year, harvest time, production area, and multi-origin sample history, to Nos. 1 to 40. The components are analyzed by dividing the 40 species described in the first, and the 30 species described in Nos. 41 to 70 in the second.

At this time, the oxidation degree of the domestic black tea sample is 80 to 100%, which is the level of complete oxidation, and the component analysis unit 100 indicates the quality characteristics of the black tea sample: moisture, ash, total nitrogen, total amino acid, theanine, reducing sugar, and total acidity. , Vitamin C, polyphenols, tannins, and flavonoids are analyzed by wet chemical analysis and output.

For example, the water content is measured using the atmospheric pressure heat drying method, which is a loss-of-drying method, the direct incineration method for ash, the Kjeldahl analysis method for total nitrogen, and the ninhydrin method for total amino acids.

In addition, reducing sugar content is measured using the DNS colorimetric method, total acidity using the acid-base titration method, tannin using the tartaric acid colorimetric method, and polyphenol using the Folin-Denies method.

In addition, the chromaticity lightness (L value), redness (a value), and yellowness (b value) of the black tea sample were measured using a colorimeter, and the total catechin and caffeine content was determined as a single substance by high-performance liquid chromatography analysis. (gallic acid), GC (gallatecatechin), EGC (epigallochatetin), C (catechin), EC (epicatechin), EGCG (epigallocatechingallate), GCG (gallocatechingallate), ECG (epicatechingallate), and CG (catechingallate). It is analyzed as an individual single component content measurement.

Here, high-performance liquid chromatography (HPLC) is a type of chromatographic analysis method in which a mixture of samples is separated using a difference in movement speed using an appropriate stationary phase and a mobile phase, and is a type of chromatography analysis method using a filler. Since it is fine and has a uniform particle size, high-level separation is possible, so the resistance to flow increases, so the solution to be separated is sent at high pressure and separation is rapid.

The spectrum measurement unit 200 receives the analysis measurement value from the sample component analysis unit 100 and uses a near infrared spectroscopy (NIRS) to obtain a black tea sample based on the main component characteristic data of domestically produced black tea. By measuring the absorption spectrum of the near-infrared spectroscopy analysis value is output.

At this time, since the present invention uses the near-infrared spectrometer 250, it is possible to simultaneously measure the contents of individual components such as total nitrogen, ash, catechin, theanine, and amino acids, so the analysis time of the conventional wet analysis method is long, It is possible to overcome difficult problems in quality control due to the use of hazardous chemicals.

The calibration formula calculation unit 310 in the calibration equation calculation and verification unit 300 receives the component analysis measurement value from the sample component analysis unit 100, and receives the near-infrared spectroscopy analysis value from the spectrum measurement unit 200. A plurality of calibration equations for simultaneous analysis of major components for quality evaluation of black tea are calculated.

At this time, the plurality of calibration equations are commonly expressed in the formula of Y = a X + b, and a is the ratio of the change in the measured value measured by the sample component analysis unit 100 to the change in the predicted value of the near-infrared spectroscopy analyzer 250 is the slope value, and b is the bias value, which is the y-axis intercept.

That is, as shown on the right side of the table in FIG. 6, tannins, total phenolic compounds (polyphenols), flavonoids, total catechins, GA (gallic acid), and GC (gallatecatechin) , EGC (epigallochatetin), C (catechin), EC (epicatechin), EGCG (epigallocatechingallate), GCG (gallocatechingallate), ECG (epicatechingallate), CG (catechingallate), etc. The values coincide with the slope and bias values in the corresponding calibration equations described in the graphs of FIGS. 10 and 11 .

In FIGS. 10 and 11, Slope means the ratio of change in the predicted value of the NIR spectroscopy analysis value to the change in the measured analysis value, and R ² means the coefficient of determination in the regression analysis technique. .

For example, calibration equations for the tannin component, total catechin component, GA component, and GC component of black tea are expressed as Equations 1 to 4 below, respectively.

[Equation 1]

Tannin Y=1.007X-0.044

[Equation 2]

Total catechins Y=1.015X-0.056

[Equation 3]

GAY=1.013X-0.003

[Equation 4]

GC Y=0.726X-0.038

In addition, as shown on the right side of the table in FIG. 7, total nitrogen, total amino acids, and nitrogen-containing main components that improve the palatability of tea by showing the umami and refreshing bitterness of domestically produced black tea by harvest time and main production area. However, the slope and bias values calculated by simultaneously measuring the caffeine content also coincide with the slope and bias values in the corresponding calibration equations described in the graphs of FIGS. 10 and 11 .

For example, calibration equations for the total nitrogen component, total amino acid component, theanine component, and caffeine component of black tea are expressed as Equations 5 to 8 below, respectively.

[Equation 5]

Total Nitrogen Y=0.964X-0.022

[Equation 6]

Total Amino Acids Y=0.991X-0.010

[Equation 7]

Theanine Y=0.937X-0.005

[Equation 8]

Caffeine Y=0.999X-0.001

In addition, as shown on the right side of the table in FIG. 8, the slope calculated by simultaneously measuring reducing sugar, total acidity, and vitamin C content, which are components of soluble solids representing sweetness and sourness of domestically produced black tea, by harvest time and main production area The values of and bias also coincide with the values of slope and bias in the corresponding calibration equations described in the graphs of FIGS. 10 and 11 .

For example, calibration equations for the reducing sugar component, total acidity component, and vitamin C component of black tea are expressed as Equations 9 to 11 below, respectively.

[Equation 9]

Reducing sugar Y=0.985X-0.077

[Equation 10]

Total acidity Y=0.968X-0.003

[Equation 11]

Vitamin C Y=1.069X-3.410

In addition, as shown on the right side of the table in FIG. 9, the quality evaluation items representing the main characteristics of domestically produced black tea by harvest time and main production area include the color lightness L value, the redness a value, and the yellowness b value of the black tea sample. and the values of the slope and bias calculated by simultaneously measuring the contents of moisture, ash, and total nitrogen, which are important components in evaluating the quality of black tea, are also the slope (Slope) and It matches the value of Bias.

For example, the calibration equations for the moisture component, ash component, chromaticity lightness, and redness component of black tea are expressed as Equations 12 to 14 below, respectively.

[Equation 12]

Moisture Y=1.003X-0.004

[Equation 13]

Ash content Y=0.997X+0.009

[Equation 14]

Chromaticity Lightness, Redness Y=X

On the other hand, the calibration equation verification unit 320 in the calibration equation calculation and verification unit 300 receives the plurality of calibration equations calculated from the calibration equation calculation unit 310 and uses the content-specific verification spectrum to analyze the sample components ( 100) cross-verify each calibration equation based on the correlation between the analysis measurement value and the absorption spectrum measured in the spectrum measuring unit 200 to verify the fit of the calibration equation to select an optimal calibration equation.

In other words, after applying various regression model equations such as modified partial least square (MPLS) and PCA (principal component analysis) modified using regression analysis technology, the optimal calibration with a high coefficient of determination (R ² ) value select an expression

In addition, the calibration equation application unit 400 receives the optimal calibration equation verified and selected from the calibration equation verification unit 320 and applies it to the near-infrared spectrometer 250 to quickly and accurately measure the individual contents of the main components of black tea at the same time. .

FIG. 12 is a graph of the absorption spectrum measured in step S300 of the method for evaluating the quality of black tea and measuring the main components shown in FIG. 2 .

FIG. 13 is a table of relative error ranges calculated by comparing the suitability verified in step S300 of the black tea quality evaluation and main component measurement method shown in FIG. 2 with conventional wet chemical analysis values.

Referring to FIGS. 1 to 13, the experimental results of the method for evaluating the quality of black tea and measuring the main components of the present invention are briefly described as follows.

As a result of testing the method for evaluating the quality of black tea and measuring major components of the present invention, as shown in FIG. 12, the near-infrared absorption spectrum was measured at 2 nm intervals in the wavelength range of 400 to 2,500 nm.

In addition, as shown in FIG. 13, the relative error range calculated in the black tea quality evaluation and main component measurement method of the present invention compared to the conventional chemical wet analysis value is moisture, ash, total nitrogen, total amino acid, theanine, Reducing sugar, total acidity, tannin, polyphenol, flavonoid, caffeine, color L value, a value, and b value were within the range of ±5%, and vitamin C and total catechins were within the range of ±20%.

As described above, the present invention simultaneously measures the main components representing quality characteristics by individual content using a near-infrared spectrometer that does not require a pretreatment process and does not use chemicals for rapid and accurate quality evaluation and quality control of black tea, and black tea samples To provide an apparatus and method for evaluating the quality of black tea and measuring major components using a near-infrared spectrometer capable of calculating and verifying an optimal calibration equation by measuring the absorption spectrum of.

Through this, the present invention quickly standardizes and grades after quality evaluation of domestically produced black tea, thereby facilitating quality management and clear decision-making for commercialization, enabling production of high-quality black tea products.

In addition, by using near-infrared spectroscopy that does not require a pretreatment process and does not use chemicals, the quality of black tea can be assessed quickly, easily and environmentally friendly, thereby increasing the commercial value and differentiating the quality. can contribute to increasing the income of

In addition, since the content of individual components of black tea can be simultaneously measured using a near-infrared spectrometer, the analysis time is shortened to less than 1 minute compared to the conventional wet analysis method, and no harmful chemicals are used. You can overcome the difficult problems of quality control.

In addition, in the era of the 4th industrial revolution, online inspection can be applied to the quality evaluation of black tea in the future, and big data on quality evaluation and quality control of domestic black tea is built, reducing production costs and black tea with uniform quality. mass production becomes possible.

In the above, several preferred embodiments of the present invention have been described with some examples, but the description of various embodiments described in the "Specific Contents for Carrying Out the Invention" section is only illustrative, to which the present invention belongs. Those of ordinary skill in the technical field will understand.

In addition, since the present invention can be implemented in various other forms, the present invention is not limited by the above description, and the above description is intended to complete the disclosure of the present invention and is common in the technical field to which the present invention belongs. It is only provided to completely inform those skilled in the art of the scope of the present invention, and it should be noted that the present invention is only defined by each claim of the claims.

100: sample component analysis unit
200: spectrum measuring unit
250: near-infrared spectrometer
300: calibration formula calculation and verification unit
310: calibration formula calculation unit
320: calibration formula verification unit
400: calibration formula application

Claims (12)

a sample component analysis unit that analyzes components of a black tea sample having a certain sample history and outputs an analysis measurement value;
a spectrum measurement unit receiving the measured analysis value and measuring an absorption spectrum of the black tea sample using a near-infrared spectrometer and outputting a near-infrared spectroscopic analysis value;
Calibration for calculating a plurality of calibration equations for the main components of black tea by receiving the analysis measurement value and the near-infrared spectroscopy analysis value, and verifying the suitability of the calibration equation calculated by the correlation between the analysis measurement value and the absorption spectrum. formula calculation and verification unit; and
A calibration equation application unit for simultaneously measuring the individual contents of the main components of black tea by receiving the calibration equation selected after the suitability is verified and applying it to the near-infrared spectrometer,
Characterized in that the sample component analysis unit measures the chromaticity brightness, redness and yellowness of the black tea sample using a colorimeter,
A device for quality evaluation and major component measurement of black tea using a near-infrared spectrometer.
According to claim 1,
The calibration formula calculation and verification unit,
a calibration equation calculation unit receiving the analysis measurement value and the near-infrared spectroscopy analysis value to calculate the plurality of calibration equations for simultaneous analysis of major components of black tea; and
a calibration equation verification unit that receives the plurality of calibration equations calculated and cross-verifies the correlation between the analysis measurement value and the absorption spectrum using a content-specific verification spectrum to verify the suitability of each calibration equation;
Characterized in that it includes,
A device for quality evaluation and major component measurement of black tea using a near-infrared spectrometer.
According to claim 1,
The constant sample history,
Characterized by the production year, harvest time, production area and tea plantation of black tea,
A device for quality evaluation and major component measurement of black tea using a near-infrared spectrometer.
According to claim 1,
The near-infrared spectrometer,
Characterized in measuring the absorption spectrum in the wavelength range of 400 to 2,500 nm,
A device for quality evaluation and major component measurement of black tea using a near-infrared spectrometer.
According to claim 1,
The plurality of calibration equations,
It is expressed by the equation Y = a X + b, wherein a is a slope value that is a ratio of change in the measured analysis value to change in the predicted value of the near-infrared spectrometer, and b is a bias value. to do,
A device for quality evaluation and major component measurement of black tea using a near-infrared spectrometer.
(a) analyzing components of a black tea sample having a certain sample history by a sample component analyzer and outputting an analysis measurement value;
(b) outputting a NIR spectroscopic analysis value by measuring an absorption spectrum of a black tea sample using a NIR spectrometer after receiving the analysis measurement value by a spectrum measuring unit;
(c) The calibration equation calculation and verification unit receives the analysis measurement value and the near-infrared spectroscopic analysis value to calculate a plurality of calibration equations for the main components of black tea, and calculates the calibration equation with the correlation between the analysis measurement value and the absorption spectrum verifying the goodness of fit of the calibration equation; and
(d) simultaneously measuring the individual contents of the main components of black tea by applying the calibration equation applied by the calibration equation application unit to the near-infrared spectrometer after receiving the calibration equation selected by verifying the suitability;
In the step (a), the sample component analysis unit measures the chromaticity, brightness, redness, and yellowness of the black tea sample using a colorimeter,
A method for quality evaluation and major component measurement of black tea using a near-infrared spectrometer.
According to claim 6,
In step (a),
The sample component analysis unit
Characterized by chemical wet analysis of moisture, ash, total nitrogen, total amino acids, theanine, reducing sugar, total acidity, vitamin C, polyphenols, tannins and flavonoids representing the quality characteristics of black tea samples,
A method for quality evaluation and major component measurement of black tea using a near-infrared spectrometer.
According to claim 7,
The sample component analysis unit
Characterized in that the content is measured using the atmospheric pressure heating and drying method for moisture, the direct incineration method for ash, the Kjeldahl analysis method for total nitrogen, and the ninhydrin method for total amino acids.
A method for quality evaluation and major component measurement of black tea using a near-infrared spectrometer.
According to claim 7,
The sample component analysis unit
Reducing sugar is characterized by measuring the content using DNS colorimetry, total acidity by acid-base titration, tannin by tartaric acid colorimetry, and polyphenol by Folin-Denies method,
A method for quality evaluation and major component measurement of black tea using a near-infrared spectrometer.
delete According to claim 6,
In step (a),
The sample component analysis unit
Characterized in that the total catechin and caffeine content of the black tea sample is measured using a high-performance liquid chromatography analysis method,
A method for quality evaluation and major component measurement of black tea using a near-infrared spectrometer.
According to claim 6,
In step (c),
Calculating a plurality of calibration equations for simultaneous analysis of major components of black tea by receiving the analytical measurement value and the near-infrared spectroscopy analysis value from a calibration equation calculation unit in the calibration equation calculation and verification unit; and
The calibration equation verification unit in the calibration equation calculation and verification unit receives the plurality of calibration equations calculated above, and cross-verifies the correlation between the analysis measurement value and the absorption spectrum using the content-specific verification spectrum to cross-verify the fitness of each calibration equation. verifying;
Characterized in that it includes,
A method for quality evaluation and major component measurement of black tea using a near-infrared spectrometer.

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