JP2006177923A - Optical freshness identifying method and device thereof for tissue from living tissue - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To identify freshness of tissues from living bodies, such as meat and the like, with sufficient accuracy at real time. <P>SOLUTION: A baseline of reflectance spectroscopy is used in enhancement of accuracy of measurement. For this purpose, by analyzing the reflected spectrum of muscular basis material of non-existence, a baseline of convex and of its lowering with shorter wavelength of the reflectance spectroscopy is applied to a measuring formula. Thereby, reflectance spectroscopy of the meat can be expressed in a form of function on the basis of a scientific principle of spectrometry and thus the mixed fraction of hemoprotein derivatives of meat and the freshness of meat can be measured quickly with high accuracy. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

The present invention relates to a method for accurately measuring the freshness of meat or the like in real time by a spectral reflection method and a measuring apparatus using such a method.

The color of the object is determined by the reflectance spectrum of the physical quantity in the visible wavelength region. Meat contains a heme protein called myoglobin, a pigment, and has a unique color tone. Meat is crimson when fresh, but it becomes a brownish unfavorable color when freshness decreases. Therefore, freshness management based on color tone is important for meat quality.

The higher the heme protein content, the stronger the light absorption, and the lower the reflectivity, the lower the brightness and the darker the meat. Heme protein binds to various molecules, and various derivatives having different colors are formed depending on the binding molecule and its state. Meat heme protein derivatives include reduced, oxygen, and oxidized forms, and the color tone changes at a mixture ratio. When the meat is fresh, it exhibits a bright red color mainly due to the oxygen type, and when the freshness decreases, the oxidized type increases to display brown or dark brown, and in the anoxic state, it exhibits a purple-red color due to the reduced type. In this way, meat exhibits various colors according to the mixing ratio of heme protein derivatives.

In actual distribution, meat freshness measurement method based on empirical rules is used. This rule-of-thumb method is primarily intended to be able to measure results equivalent to those who measure the freshness of meat visually using the Beef Color Standard (BCS), and this type of meat freshness measuring device is patented. It is disclosed in Document 1. B.C.S. is intended for use in carcass rating evaluation. This is a color sample in which the darkness of the carcass color, which is extremely high in the freshness of 1-2 days after slaughter, is determined, and the oxidized heme protein derivative that appears brown due to the decrease in freshness is not considered at all. As a result, the freshness cannot be determined.

Accordingly, various proposals have been made for scientifically obtaining information that serves as an index of meat freshness, quality and the like from color tone using spectroscopic means.

One proposal is to extract meat heme protein with a solution and measure the absorbance of the solution. This absorbance method is an application of the principle established as the Beer-Lambert law, and the measured values for the solution are correct. However, this method has the following problems. 1) Heme protein cannot avoid contact with air during extraction, and reduced heme protein cannot be measured because reduced heme protein becomes oxygenated. That is, only two of the three components can be measured by the extraction method. 2) Normally, heme protein cannot be extracted completely, and an error occurs in the quantitative value. 3) Not applicable to products that change the hemoprotein derivative when opened, such as in packaged meat. 4) Since measurement takes a long time, rapid measurement and large quantity measurement cannot be performed. 5) Since the color tone of the transmitted light of the extraction solution is different from the color tone of the reflected light of the meat, these color tones cannot be handled in the same way.

Absorbance methods have established the measurement principle for measuring heme protein derivatives, but in the case of meat, the ratio of the derivatives changes during the processing process such as extraction, so the reduced, oxygen, and oxidized forms of heme protein derivatives There is a fatal defect that prevents the mold from being measured correctly.

Instead of this absorbance method, a method for directly analyzing heme protein in muscles in a solid state has been proposed as reflection spectroscopy. This reflection spectroscopy is a non-destructive method because it can be measured as meat without the need for solution extraction, and is a useful method because it can perform large-scale measurement in real time.

Patent Document 2 discloses a technique using reflection spectroscopy, but this technique does not consider the baseline when measuring the reflection spectrum of meat. In addition, since the selected wavelengths for measurement use the isosbestic points between reduced, oxygen, and oxidized heme proteins such as 474, 572, 597, and 614 nm, it is impossible to measure other than these three derivatives. Further, according to these selected wavelengths, the wavelength accuracy of the measuring instrument is limited to a large measuring instrument having a wavelength accuracy of 1 nm or less or measurement of reduced, oxygen, and oxidized heme proteins, and there is no versatility.

Patent Document 3 proposes a method of calculating from the second derivative value of transmitted reflectance at wavelengths of 624, 616, 694, and 744 nm in order to measure the ratio of oxidized heme protein derivatives. The scientific basis for calculating the ratio of the oxidized heme protein derivative based on these selected wavelengths and second-order differential values of the transmitted reflectance is scarce, and it is difficult to verify whether the obtained measurement results are correct. In addition, meat has a greatly different color tone for reduced, oxygen and oxidized types, but only the proportion of oxidized heme protein derivatives can be measured. Therefore, the information on the freshness and the color tone is insufficient. In order to obtain a second derivative such as 624, 616, 694, and 744 nm, a measurement method that requires a wavelength accuracy of 1 nm or less is a large machine. Therefore, since portability cannot be expected, it is difficult to develop the application at distribution sites.

Krzywicki has proposed a method of using muscle base reflectance as a base line in reflection spectroscopy (Non-patent Document 1). FIG. 1 shows the reflectance spectrum of meat. The higher the heme protein content, the lower the reflectance spectrum. As shown in FIG. 1, the higher the overall wavelength, the higher the reflectance. Since the reflectance on the long wavelength side means that light absorption of heme protein is small, there is an idea that the muscle base reflectance is regarded as a reflectance near 700 nm as shown in FIG. Krzywicki considered that the spectrum of the muscle base reflectivity was around 700 nm (Non-patent Document 1). The muscle base reflectivity is a base that does not contain heme protein, and is a value that is not related to the amount of heme protein content. However, as shown in the figure, the reflectivity near 700 nm is lower as it is higher depending on the amount of heme protein in the meat, and is greatly different. Therefore, it cannot be regarded as the muscle base reflectivity. Further, as apparent from FIG. 1, there is no scientific basis that the muscle base reflectivity shows a constant value at all wavelengths.

Non-Patent Document 2 describes an example in which only an oxidized form is measured using reflectance values of two wavelengths of 525 nm and 575 nm in measurement of a heme protein derivative in meat by reflection spectroscopy. Even in the measurement of only a simple oxidized form, it has been clarified that an error occurs due to a difference in lightness of meat, that is, a heme protein content in the meat.

JP-A-4-350540 Japanese Patent Laid-Open No. 3-96838 JP 2003-121351 A Krzywicki, K. Meat Science, 3, 1-10, 1979 Izumimoto, Japan Agricultural Chemical Society, 50, 55-59, 1976

In order to accurately measure changes in heme protein based on scientific principles, it is necessary to measure by a relational expression that takes into account the spectrum of muscle base reflectance as the baseline of reflection spectroscopy. However, since the wavelength-dependent muscle base reflectivity has not been clarified so far, the value of the muscle base reflectivity with scientific evidence is not taken into account in the measurement.

The present invention has been made on the basis of the above problems, and the content of a substance having spectroscopic properties contained in biological tissue such as meat by reflection spectroscopy using a muscle base reflectance having a scientific basis as a baseline. The purpose of this is to calculate the mixing ratio and to accurately identify the freshness of living tissue such as meat from these numerical values in real time.

で表される多変数一次式マトリクス（上式において、Pf1, Pf2 … Pfnは成分の混在割合を表す変数であり、ｆ1、ｆ2…ｆnは混在成分の種類を表し、G'は成分含量と比例する関数値であり、α'は光吸収係数を表し、α'の添え字は異なる波長λならびに異なる混在成分ｆを表し、λ₁〜λ_nは異なる波長を表し、λ_isoは等吸収点（isosbestic point）の波長を表し、またｎは成分数を表す。）で表されることを特徴とする上記（１）から（５）に記載の生体組織の光学的鮮度識別方法を提供すること、（７）前記式（１０）においてｎが３であり、分光学的性質を有する物質が食肉に含まれるヘムタンパク質の酸素型、還元型および酸化型の３成分であることを特徴とする上記（６）に記載の生体組織の光学的鮮度識別方法を提供すること、（８）生体組織に光照射を行う光源、生体からの反射光を受光する手段、受光された反射光をスペクトル分光する手段、スペクトルデータを記憶する手段、スペクトルデータを用いて所定の演算式に基づいて生体組織に含まれる分光学的性質を有する物質の含量および混在割合を演算する手段、および演算されたデータを出力する手段を備えて構成される生体鮮度識別装置であって、上記の演算手段が式（１０）で表される演算式に基づくソフトウェアを備えていることを特徴とする生体の光学的鮮度識別装置を提供することにより、上記の課題を解決する。 The present invention provides (1) the content and / or mixture ratio of a substance having spectroscopic properties existing in a biological tissue using a predetermined arithmetic expression from information of spectral reflection spectrum obtained by irradiating the biological tissue with light. And using a muscle base reflectance curve as a baseline in spectral reflectance measurement in an optical freshness identification method for biological tissue, characterized in that the chemical composition and freshness of biological tissue are identified from the calculated information. And (2) using a muscle base reflectance spectrum value expressed by a convex curve on a lower wavelength as the wavelength of the muscle base is lower. And (3) a muscle having a reflectance of 45% to 55% between the actual meat and the bleached meat at a wavelength of 700 nm. (1) Providing the optical tissue freshness identification method according to the above (1) and (2), characterized by using a base curve, (4) The biological tissue is meat (above) 1) to 3) an optical freshness identification method for living tissue, and (5) an oxygen type, a reduced type and an oxidized type 3 of heme protein containing a substance having spectroscopic properties in meat. Providing an optical freshness identification method for living tissue according to any one of (1) to (4) above, characterized in that:

(In the above equation, Pf1, Pf2 ... Pfn are variables representing the mixing ratio of the components, f1, f2 ... fn represent the types of the mixed components, and G 'is proportional to the component content) Α ′ represents a light absorption coefficient, a subscript of α ′ represents different wavelengths λ and different mixed components f, λ _{1 to} λ _n represent different wavelengths, and λ _iso represents an isosbestic point ( isosbestic point), and n represents the number of components.) The optical tissue freshness identification method according to (1) to (5) above, characterized in that (7) In the above formula (10), n is 3, and the substance having spectroscopic properties is an oxygen type, a reduced type and an oxidized type of heme protein contained in meat, 6) Providing the optical tissue freshness identification method according to 6), (8) Included in biological tissue based on a predetermined arithmetic expression using spectral data, light source for irradiation, means for receiving reflected light from living body, means for spectrally spectrally analyzing received reflected light, means for storing spectral data A biological freshness identification device comprising means for calculating the content and mixing ratio of a substance having spectroscopic properties, and means for outputting the calculated data, wherein the calculation means is expressed by equation (10). The above-described problem is solved by providing an optical freshness identification device for a living body characterized by including software based on an arithmetic expression represented.

For the measurement of heme protein by reflection spectroscopy, the accuracy of the measurement principle is improved by following the theory of scientific principles, and it can be rationally developed for specific applications. The method of the present invention is a method for accurately measuring heme protein based on scientific principles by elucidating the β value corresponding to the muscle base reflectivity as described above and using it.

According to the present invention, 1) Since a principle equivalent to a multi-component measurement method based on a spectrophotometric method for transmitted light can be employed, the muscle base reflectance is used as a baseline for reflection spectrum measurement in the calculation formula (10). It is possible to calculate the content of substances having spectroscopic properties contained in living tissue and / or the mixture ratio of multiple components in real time, so that the freshness of living tissue can be accurately determined with scientific basis. It becomes possible to know well. In particular, it is possible to accurately calculate the mixing ratio of reduced, oxygen, and oxidized dyes that are heme protein derivatives. Therefore, according to the present invention, it is possible to provide extremely useful information in quality evaluation and quality control of living tissues of animals and plants, particularly meat.

Further, according to the present invention, the following effects can be expected. 2) Since reflection spectroscopy is a non-destructive method, the state of the contents can be measured directly without any processing on the package contents. 3) It can be applied to a method that can accurately measure the degree of color development, which is the formation ratio of nitrosyl (nitroso) heme protein derivatives during processing such as heated meat. 4) Can be used as color tone quality management information. For example, the reduced and oxidized types of heme protein derivatives have poorer color quality than the oxygen type, but if the reduced type is converted to the oxygen type over time, the reduced type and oxygen type Management by predicting good color quality. 5) In the rating of beef carcass, the quality of the meat is visually judged using the beef color standard (BCS). Since this rating is done with fresh meat, the heme protein derivatives are a mixture of oxygen and reduced forms. Therefore, if there are many vivid oxygen types, it will be judged as good, and if there are many non-brilliant reduced types, it will be judged as bad. Since the reduced form is converted to the oxygen form in the flow process, there is an irrational aspect. Since the system of the present invention can be developed from predicting the reflectance spectrum or color tone of a specific derivative of oxygen type from the color tone of oxygen type, reduced type and oxidized type of heme protein derivatives, Avoid irrational ratings. 6) The methods for measuring the reduced, oxygen, and oxidized forms of meat heme protein derivatives can also be measured by the same method for the ratio of other nitric oxide derivatives. 7) Measurement data is acquired by an online computer, and measurement results are obtained in real time by computer computation. 8) Anyone can instantaneously measure with high accuracy by programming the arithmetic expression of the present invention.

As shown in FIG. 2, the biological tissue optical freshness identification apparatus according to the present invention has a light source 1 that irradiates light to face a subject placed on a test bench. As the light source, a fluorescent lamp, a halogen lamp, a light emitting diode, an organic EL, a laser, a flashlight, or the like can be used. The light source may be white light or specific single wavelength light limited by a filter. It can be selected and used according to the measurement purpose. Reflected light from the living body is split and received by the spectroscopic / light receiving unit, and spectral spectrum analysis is performed for each wavelength. This information is stored in the storage device 3 and at the same time, the calculation means 4 calculates the content of the material having spectroscopic properties and the mixing ratio of the components based on a predetermined calculation formula. This information is sent to the output means 5 and displayed as text or image information on a liquid crystal display, an organic EL display, a light emitting diode display, etc., and paper recording is possible by adding a print function. Such an apparatus can be selected as a fixed installation type or a portable type according to the purpose of use.

The measuring instrument and the computer are connected online, the measurement data is analyzed in real time, and the mixing ratio of multiple components can be displayed instantaneously. Here, the measurement data is input to the computer, and the display of the analysis result is output. If the computer is connected to the communication line, the network can be used to provide the analysis results not only in Japan but throughout the world.

The measurement principle according to the present invention will be described in detail below. The basis of this principle is that the function (G) with the reflectance (R) as a variable is linearly related to the heme protein content (C). The function uses α and β as constants.

G = f (R) (1)
G = α ・ C + β (2)

It becomes. β is G when C = 0. β is equivalent to the muscle base of meat when there is no heme protein in the meat when C = 0, and cannot be measured because it does not exist. This muscle base reflectance is called "muscle base reflectance". The muscle base reflectivity is an indispensable value as the base line (baseline) of reflection spectroscopy. That is, if β is determined at all wavelengths of the reflectance spectrum,

(G-β) = α · C (3)

Thus, (G-β) on the left side can be handled in the same manner as the absorbance coefficient of the absorbance method established in principle. This establishes a theoretical basis for reflection spectroscopy measurement and is expected to improve measurement accuracy.

A specific example of the function of Expression (1) is shown (Non-patent Document 2). K / S (absorption coefficient / scattering coefficient ratio) is derived from the reflectance (R) and expressed by the following equation.

G = K / S = (1−R) ² / (2R) (4)

A linear relationship corresponding to the function G in Equation (2) is recognized between K / S and the heme protein content (C). As a result, a constant β value is obtained regardless of the amount of heme protein contained in the meat, and it has been clarified that the reflectance at a wavelength of 525 to 575 nm of the muscle substrate is 40 to 43% from the β value. (Non-Patent Document 2).

Substituting the muscle base reflectance β value into Equation (3) and setting (G−β) as G ′, G ′ has a linear relationship with the heme protein content.

G '= G-β = α · C (5)

α is an extinction coefficient in reflection spectroscopy. Λ, which means a value at an arbitrary wavelength, is appended with a subscript to obtain Equation (6).

G ' _λ = α _λ · C (6)

この式において、Ｐoxy、Pred、Pmetは求めるヘムタンパク質の誘導体の各々酸素型、還元型、酸化型の割合である。αは反射分光法の吸光係数であり、添え字のλ付の異なる数値は異なる波長を示す。G'は式（５）で示される反射率（Ｒ）から導かれる関数の値、Cはヘムタンパク質含量である。 From this, it can be handled in the same manner as the principle of spectrophotometry, and the mixing ratio of reduced, oxygen, and oxidized forms of heme protein derivatives in meat can be measured. The equation is expressed as a matrix as follows.

In this formula, Poxy, Pred, and Pmet are the ratios of oxygen type, reduced type, and oxidized type of the desired heme protein derivative, respectively. α is the extinction coefficient of reflection spectroscopy, and different numerical values with the subscript λ indicate different wavelengths. G ′ is a value of a function derived from the reflectance (R) shown in Equation (5), and C is a heme protein content.

When meat heme protein derivatives are oxygen, reduced, and oxidized, the reflectance (R) at a wavelength of 525 nm is equal and is called the isosbestic point. That is, the reflectance at a wavelength of 525 nm does not depend on the hemoprotein derivative, but only on the content (C). Therefore, from Equation (6), the value at the isosbestic point is shown using the subscript λiso.

G ' _λiso = α _λiso · C (8)

Is obtained.

式（９）はCの代わりにG'λ_isoを用いることによって、含量（C）を測定しないで、ヘムタンパク質の誘導体の役割（Poxy、Pred、Pmet）を求める式である。 Equation (8) shows that G′λ _iso is directly proportional to the content (C). Therefore, if G′λ _iso is used in place of the content (C) in equation (7) and the newly obtained left side coefficient is α ′, the following equation is obtained.

Expression (9) is an expression for determining the role of heme protein derivatives (Poxy, Pred, Pmet) without measuring the content (C) by using G′λ _iso instead of C.

The relational expression of equation (9) is equivalent to the principle of the multi-component measurement method by spectrophotometry of transmitted light. Therefore, it is not necessary to specify the selected wavelength used for the measurement, and the degree of freedom is higher than the method of specifying the specific wavelength of the conventional method, so that measurement can be performed with high accuracy even with a measuring instrument having a wide measurement wavelength interval.

In formula (9), Poxy, Pred, and Pmet are variables, but all other values are values derived only from the reflectance spectrum. The right side is the measured value. Therefore, by solving this equation, the variables Poxy, Pred, and Pmet are determined only from the reflectance spectrum data. That is, when the values of Poxy, Pred, and Pmet are determined, the proportion of oxygen type, reduced type, and oxidized type of heme protein derivatives can be calculated only from the reflectance spectrum, and it is possible to quickly and accurately measure the freshness of meat. .

なお、式中の記号は前記と同じである。 As described above, the general formula of formula (10) can be applied to the multi-component substance having spectroscopic properties contained in the living tissue.

The symbols in the formula are the same as described above.

The reflectance spectrum of the muscle structure assumed to be a colorless structural component and the base line of reflection spectroscopy is unexistent and unknown. Therefore, the muscle base and mythical baseline for myoglobin measurement by reflection spectroscopy were estimated as follows.

The baseline reflectance spectrum was analyzed as an analogy of bleached meat, and the change in the bleached meat was analyzed. As a result, the characteristic of the dark curve shown in FIG. 3 was obtained. The light gray curve in FIG. 3 shows a number of reflectance spectra for the meat bleach sample. The bleached sample shows a smooth curve with no light absorption of heme protein as seen in FIG. 1 because heme protein is bleached. Moreover, the reflectance becomes lower as the wavelength is shorter, and the curve is convex upward.

Among these reflectance characteristics, the reflectance spectrum of the muscle substrate that does not contain heme protein is lower than that of the bleached sample (the reflectance at 700 nm in FIG. 3 is around 55%), and real meat containing heme protein (of FIG. 1). The reflectance spectrum is higher than the reflectance at 700 nm (around 45%). From this, the reflectance spectrum of the muscle substrate is estimated to be a curve in a limited range where the reflectance at 700 nm is about 45% to about 55%. However, there is a considerable difference depending on the measurement method of the reflected light of the measuring device, and considering this, the reflectance of the muscle substrate is considered to be in the range of approximately 40% to 60%.

The reflectance spectrum of the muscle substrate is expressed by an equation having a linear relationship with the inverse value of the fourth power of the wavelength. A linear relationship is recognized between 1 / Y and 1 / X, which are the reciprocals of the CIE tristimulus values, and a linear relationship of muscle base spectrum characteristics and a linear relationship of meat are recognized. The intersection of these two straight lines means that it corresponds to a muscle substrate, and the values of the intersection are 1 / Y = 2.25 and 1 / X = 2.23, and the reflectance at 700 nm is the spectral characteristic of FIG. Corresponds to 50% spectrum. It was confirmed that the spectrum of the muscle substrate obtained by the characteristic analysis on the CIE color tone value and the retroreflectance corresponds to the β value (Equation 2) and is suitable as the baseline of reflection spectroscopy.

Hereinafter, calculation of the content ratio of the heme protein derivative contained in the meat sample will be described in detail with reference to examples. However, the present invention is not limited to these examples. In this example, a characteristic curve having a reflectance of 50% at 700 nm was selected from the muscle base reflectance spectral characteristic curve (FIG. 3). Meat samples were obtained by wrapping commercially available beef thighs and backs (longest chest muscle) into 3 cm long x 5 cm wide x 1 cm thick wrapped with Kurelap (Kureha Chemical Industries). The spectral reflection spectrum was measured in a wavelength range of 400 to 700 nm by a reflection spectrophotometer (Minolta CM1000 type). The content ratio of the heme protein derivative contained in the meat sample was calculated from the obtained data using the relational expressions of the above formulas (5) and (9). The color value is based on the CIELAB1976 color system.

(When the heme protein derivative of the meat sample is of oxygen type)
The result of the calculation is shown in FIG. The horizontal axis L * in the figure is the brightness defined in JIS Z8729, and the vertical axis is the ratio of the derivative. As shown in the figure, it is clearly distinguished and measured that the heme protein derivative is of oxygen type in all meats having greatly different lightness, that is, all meats having a very dark color to a light color. On the other hand, reduced and oxidized heme protein derivatives are clearly discriminated and measured at a value around 0%.

(When heme protein derivative of meat sample is reduced)
The result of the calculation is shown in FIG. The sample and measuring apparatus are the same as those in Example 1. The horizontal axis L * in the figure is the brightness defined by JIS Z8729, and the vertical axis is the ratio of derivatives. The reduced form is clearly distinguished and measured. On the other hand, oxygen-type and oxidized-type heme protein derivatives are measured at values near 0%.

(When the heme protein derivative of the meat sample is oxidized)
The result of the calculation is shown in FIG. The sample and measuring apparatus are the same as those in Example 1. The horizontal axis L * in the figure is the brightness defined by JIS Z8729, and the vertical axis is the ratio of derivatives. Oxidized forms are clearly distinguished and measured. On the other hand, oxygen-type and reduced-type heme protein derivatives are clearly discriminated and measured at a value around 0%.

(Changes in storage ratio of heme protein derivative in fresh beef)
The calculation results are shown in FIG. The measuring instrument is the same as that in Example 1. Over time, the reduced type changes to the oxygen type, and a good bright red color is observed. Moreover, since the change to an oxidation type is not recognized, it is clearly identified as meat of a bright red color.

(Changes in the proportion of heme protein derivatives in fresh thigh meat during storage)
The calculation results are shown in FIG. The measuring instrument is the same as that in Example 1. Although the reduced type decreases with time, the change to the oxygen type is slight, and no good bright red color is observed. On the other hand, the increase in the oxidized form is remarkable, and the browned freshness is clearly identified as poor meat.

The measurement method of the present invention does not depend on the heme protein content in meat and can be applied to all meat. The conventional method (Patent Documents 1, 2, 3 and Non-Patent Document 1) does not explicitly indicate how lightness can be applied, but if the scientific principle does not consider “muscle base reflectance”, It is inevitable that the measured value varies depending on the brightness. If the accuracy is low, it is not possible to accurately measure all three types of oxygenated, reduced, and oxidized forms of heme protein derivatives in meat samples. For example, three types of oxygen, reduced, and oxidized types are mixed in meat. Nevertheless, the measurement is limited to the oxidation type only. According to this method, as shown in FIGS. 4, 5, and 6, all three types of oxygenated, reduced, and oxidized heme protein derivatives can be measured with high accuracy.

The measurement method of the present invention can accurately measure all three types of oxygenated, reduced, and oxidized heme protein derivatives in real time. This method is capable of nondestructive measurement without opening the heme protein derivative in the packaged meat, which is impossible with the extraction method, and samples are collected and transferred to laboratories etc. Applicable to the factory line. Since real-time measurement is possible, large-scale and rapid measurement is possible.Thus, the estimation by the conventional statistical method such as sampling inspection can estimate the proportion of defective products, but cannot exclude defective products themselves. Since inspection is possible, defective products can be identified on the spot.

The measuring method of the present invention is a measuring method to which scientific principles are applied. Therefore, the present invention is not limited to animal living organisms, and is applied to, for example, identification measurement of freshness and ripeness accompanied by discoloration of fruits, and a management system for agricultural products such as fruits based on the relationship between color quality and factors of chemical components Can be used for

It is a figure which shows the reflection spectrum of meat. It is a figure which shows the outline of the optical freshness identification apparatus of this invention. It is a figure which shows the reflection spectrum of the muscle base material of meat. It is a figure which shows the relationship between the derivative ratio of the oxygen-type heme protein of meat, and the brightness. It is a figure which shows the relationship between the derivative | guide_body ratio of reduced heme protein of meat, and the brightness. It is a figure which shows the relationship between the derivative ratio of the oxidation type heme protein of meat, and the brightness. It is a figure which shows the change in storage of the derivative | guide_body ratio of the meat heme protein which is fresh. It is a figure which shows the change in the storage of the heme protein derivative ratio of the meat which is not fresh.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Light source 2 Spectroscopic / light-receiving part 3 Memory | storage device 4 Calculation means 5 Output means

Claims (8)

Calculate the content and / or mixture ratio of a substance having spectroscopic properties present in the living tissue from the information of the spectral reflection spectrum obtained by irradiating the living tissue with light using a predetermined arithmetic expression. In the optical tissue freshness identification method characterized in that the chemical composition and freshness of biological tissue are distinguished from each other, a muscle base reflectance curve is used as a baseline in spectral reflectance measurement. Optical freshness identification method. 2. The method for discriminating optical freshness of biological tissue according to claim 1, wherein the muscle base reflectance is lower as the wavelength is shorter, and the muscle base reflectance spectrum value represented by a convex curve is used. 3. The method for discriminating optical freshness of biological tissue according to claim 1, wherein a muscle base curve having a reflectance of 45% to 55% between real meat and bleached meat at a wavelength of 700 nm is used. 4. The method for discriminating optical freshness of biological tissue according to claim 1, wherein the biological tissue is meat. 5. The method for discriminating optical freshness of biological tissue according to claim 1, wherein the substance having spectroscopic properties is an oxygen type, a reduced type and an oxidized type of heme protein contained in meat. The arithmetic expression is expression (10),

6. The method for discriminating optical freshness of biological tissue according to claim 1, characterized in that it is expressed by a multivariable linear expression matrix expressed by: In the above equation, Pf1, Pf2... Pfn are variables representing the mixing ratio of components, f1, f2... Fn represent the types of mixed components, G ′ is a function value proportional to the component content, and α ′ is light. The absorption coefficient represents an absorption coefficient, the suffix α ′ represents different wavelengths λ and different mixed components f, λ1 to λn represent different wavelengths, λiso represents the wavelength of an isosbestic point, and n represents the number of components. 7. In the formula (10), n is 3, and the substance having spectroscopic properties is an oxygen type, a reduced type and an oxidized type of heme protein contained in meat. Discriminating method of optical freshness of living tissue. A light source for irradiating a living tissue with light, a means for receiving reflected light from the living body, a means for performing spectral spectroscopy on the received reflected light, a means for storing spectral data, and a living body based on a predetermined arithmetic expression using the spectral data A biological freshness identification apparatus comprising means for calculating the content and mixing ratio of a substance having spectroscopic properties contained in a tissue, and means for outputting the calculated data, wherein the calculation means is a formula An optical freshness identification device for living tissue, comprising software based on the arithmetic expression represented by (10).

In the above equation, Pf1, Pf2... Pfn are variables representing the mixing ratio of components, f1, f2... Fn represent the types of mixed components, G ′ is a function value proportional to the component content, and α ′ is light. Represents an absorption coefficient, the suffix of α ′ represents different wavelengths λ and different mixed components f, λ1 to λn represent different wavelengths, λiso represents the wavelength of an isosbestic point, and n represents the number of components.

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