CN104374705B - Beef freshness detection device and detection method - Google Patents

Abstract

The invention discloses a beef freshness detection device and detection method, the beef freshness detection device includes an opaque casing, a controller, a laser array, a spectrometer, a light intensity adjusting device, a rectangular container which is arranged in the casing and is provided with an opening on the upper end, a rectangular sample tray arranged in the container, a bracket arranged on a base plate of the casing, a light emitting head which is arranged on the bracket and used for irradiating light to a sample, and a light receiving head used for receiving reflected light of the sample; the light intensity adjusting device, the laser array and the light emitting head are orderly electrically connected, the light receiving head and the spectrometer are electrically connected, the container and the sample tray are made of a magnetic-impermeable material, the container is provided with a liquid, the sample tray is suspended above the liquid surface, a plurality of vertical holes of m order matrix arrangement are arranged on the bottom of the container, and the beef freshness detection device has the advantages of fast detection speed; more point detection, reliable detection data and higher precision.

Description

Degree of beef freshness detection means and its detection method

Technical field

The present invention relates to measurement techniques for quality detection of meat detection technique field, especially relate to one kind and can accurately and rapidly detect cattle The whether corrupt degree of beef freshness detection means of meat and its detection method.

Background technology

Beef has the characteristics that nutritious and in good taste, deep is liked by consumers in general.

But, beef is highly susceptible to pollute and goes bad.During storage, propagation with microorganism and a series of Physicochemical change, the freshness of beef decreases.The nutritional labeling quilt that protein, fat and carbohydrate etc. enrich Antibacterial and enzyme utilize, and produce ammonia, sulfuration ammonia, aldehydic acid, aldehyde, ketone, the sour gas of ethanethio, alcohol and carboxylic acid.Metabolite In aldehyde, ketone, ester and other low molecular compound make beef produce abnormal flavour.

At present, generally adopt spectrum stimulus light source to irradiate sample both at home and abroad and (adopt a normally opened laser instrument battle array Row or LED lamp impinge upon on sample), and gather the reflection that incident illumination is mapped to diffusing after sample or passes through sample Light, is analyzed to diffusing reflection spectrum or reflectance spectrum, finally realizes the detection to sample quality；But, this detection method Have that collected detection information amount is less, the relatively low deficiency of the precision of detection.

Chinese patent Authorization Notice No.: cn101769889a, in authorized announcement date on July 7th, 2010, discloses a kind of agricultural production The electric nasus system of product Quality Detection, mainly completes the gas enrichment module to low concentration odor trap including one, a main handle Olfactory signal is converted into air chamber gas path module and the sensor array of the signal of telecommunication, and one is mainly carried out to sensor array output signal Filtering, analog digital conversion, the Conditioning Circuits of Sensor of feature extraction and data preprocessing module, a pair of signal is identified and sentences Embedded system that is disconnected and carrying data storage, a display and result output module；Described gas enrichment module is by being filled with The adsorption tube of adsorbent, heating wire and attemperating unit are constituted.This invention has single function, the deficiency of detection time length.

Content of the invention

The present invention is to overcome the shortcomings of that detection method precision of the prior art is low and time-consuming, there is provided Yi Zhongke Accurately and rapidly to detect the whether corrupt degree of beef freshness detection means of beef and its detection method.

To achieve these goals, the present invention employs the following technical solutions:

A kind of degree of beef freshness detection means, including light tight housing, controller, laser array, spectrogrph, light intensity Adjusting means, located at the rectangular vessel of the upper end open in housing, the rectangle sample pallet in container, located at Housing Base On support, on support for sample irradiation light light emitting head and for receive sample reflected light light-receiving Head；Light intensity adjusting means, laser array, light emitting head are sequentially connected electrically, and light-receiving head is electrically connected with spectrogrph；Container and Sample tray is made by non-magnet_conductible material, is provided with liquid in described container, and described sample tray is suspended on liquid surface, holds Device bottom is provided with several vertical cores of the arrangement in m rank square formation, is equipped with positioning and uses in the equal upward opening of each vertical core and vertical core Electric magnet, interior in the middle part of described sample tray be provided with positioning magnet piece, through sample tray lower surface metal column upper end with fixed Position magnet piece is connected, and positioning electric magnet uses the opposite polarity of the magnetic pole of magnet piece opposite end with positioning；

Some pieces of traction magnet pieces are equipped with each edge of sample tray, each side of container are equipped with some Block power for traction Magnet；Light intensity adjusting means, spectrogrph, each block of positioning electric magnet and each block of power for traction Magnet all with control Device electrical connection processed.

The light intensity adjusting means of the present invention is used for adjusting the light intensity of the light source that laser array sends, and each positioning is used Electric magnet is used for sample tray positioning, and power for traction Magnet is used for drawing sample tray and moves, being provided for sample of liquid Product pallet is provided and departs from the buoyancy being located by connecting with container, so that the present invention can detect to the multiple points on sample, And the detection signal that each point of irradiation obtains is carried out with data analysiss, and obtain the freshness of beef sample, the scope of detection is more Extensively, detection information more comprehensively, improves the reliability of testing result.

The principle of degree of beef freshness is learned in light detection: after a branch of light irradiation sample, by institute in different freshness samples The different chemical feature groups comprising are different, are different therefore for the degree of absorption of different wave length incident illumination, because And the intensity of each wavelength light is different in reflected light, therefore can go to characterize the freshness of sample according to these information.But, If the light intensity of incident illumination is fixed, incident illumination is stably radiated on sample, and each chemical group in sample is not for The degree of absorption of co-wavelength light is in saturation although can be detected information, but quantity of information does not enrich, detection Accurately fixed relatively low.

The present invention is the incident illumination irradiating sample being continually changing using light intensity, gradually big or reduce in the intensity of incident illumination Change procedure in, different groups are gradually big to the absorption of respective wavelength light or reduce, now at the degree of absorption of group During unsaturation, saturation diminuendo, in reflected light, comprise more detection informations, thus enabling the detection signal obtaining more Accurately symbolize the freshness of beef.

Therefore, the present invention has that detection speed is fast, and test point is more, the reliability of detection data and the higher spy of precision Point.

Preferably, being equipped with motor in container below each vertical core, each positioning electric magnet respectively with each electricity The vertical rotating shaft of machine is connected, and positioning electric magnet is provided with keeper, and keeper upper end offers M shape groove, metal column Lower end is provided with the M shape projection corresponding with M shape groove, and each motor is electrically connected with the controller.Metal column is provided with bullet Spring, keeper is made using metal material.

Motor is used for driving sample tray to rotate, so that incident illumination is mapped in the difference of sample, in detection process Detected point is more, comprises more freshness information in the detection signal of acquisition.

Preferably, described laser array includes 6 bundling and Single wavelength laser that wavelength is arranged in order Device, the wavelength of each single wavelength laser is respectively 630nm, 925nm, 534nm, 780nm, 610nm and 730nm.Pin of the present invention Physicochemical property to beef, selects the laser instrument of above 6 wavelength to be detected, can more project the detection feature of beef, Improve the accuracy of detection.

Preferably, described light intensity adjusting means includes data collecting card and power amplifier, described data collecting card It is provided with the signal input interface for being electrically connected with the controller, described data collecting card is electrically connected with the input of power amplifier Connect, the outfan of described power amplifier and the power electric connection of laser array.

Controller produces the waveform for controlling intensity variation, and this waveshape signal is gathered by data collecting card, and exports To on power amplifier, the outfan of power amplifier and the power electric connection of laser array, thus by controlling laser instrument The regulation of the light intensity of light source that the power supply realization of array sends to laser array, and strong to sample irradiation by light emitting head The incident illumination of degree change.

Preferably, support is in l shape, including horizon bar and column；Light emitting head and light-receiving head pass through respectively montant with Horizon bar is connected；, all in bar shaped, the pole polarity outside each piece of traction magnet piece is identical for each piece of traction magnet piece.

A kind of detection method of degree of beef freshness detection means, comprises the steps:

(6-1) according to CNS gb/t 5009.44-2003, the volatilization of the different resting period beef sample of detection Property alkali nitrogen tvb-n value, and obtain and m²Individual sample detection point corresponding freshness threshold respectively；

(6-2) sample preparation: choose lamellar meat from beef to be detected as detected sample；

(6-3) detected: by controller and light intensity adjusting means, spectrogrph, each block of positioning electric magnet and each piece Power for traction Magnet electrically connects, and sample is kept flat on sample tray；

(6-3-1) controller is by each each block of positioning electric magnet and the energising of each block of power for traction Magnet and power-off, Control sample tray along bow font movement to each vertical core；

(6-3-2) after metal column inserts a vertical core, controller adjusts laser instrument by light intensity adjusting means The detection light of array output, detection light rises to maximum mat from 0 according to sine curve, then from maximum mat according to sine Curve drops to 0；Detect that rear spectrogrph obtains m²Individual detection signal spect (t)；

(6-4) controller is to m²Individual detection signal spect (t) all does following data processing:

By detection signal spect (t) input one layer of accidental resonance model:

In, controller calculates v (x, t, α) for the first derivative of x, second dervative and three order derivatives,

And make equation be equal to 0, obtain two layers of accidental resonance model:

Set noise intensity d=0,Spect (t)=0, n (t)=0；It is calculated facing of a Dividing value isThe marginal value of a is substituted in one layer of accidental resonance model, and sets x₀(t)=0, sn₀=0, with quadravalence one layer of accidental resonance model of jade for asking rain Ge Kuta Algorithm for Solving, obtain $x_{n+1}\left(t\right)=x_n\left(t\right)+1/6[{\left(k_1\right)}_n+(2-\sqrt{2}){\left(k_2\right)}_n+(2+\sqrt{2}){\left(k_3\right)}_n+{\left(k_4\right)}_n],$ N=0,1 ..., n-1

Wherein undetermined coefficient:

(k₁)_n=a (α x_n-1(t))²-b(αx_n-1(t))³+sn_n-1

${\left(k_2\right)}_n=a(\mathrm{\α}{x}_{n-1}\left(t\right)+\frac{{\left(k_1\right)}_{n-1}}{3})-b{(\mathrm{\α}{x}_{n-1}\left(t\right)+\frac{{\left(k_1\right)}_{n-1}}{3})}^3+{\mathrm{sn}}_{n-1}$

${\left(k_3\right)}_n=a({\mathrm{\αx}}_{n-1}\left(t\right)+\frac{{\left(k_2\right)}_{n-1}}{3})-b{({\mathrm{\αx}}_{n-1}\left(t\right)+\frac{\sqrt{2}-1}{3}{\left(k_1\right)}_{n-1}+\frac{2-\sqrt{2}}{3}{\left(k_2\right)}_{n-1})}^3+{\mathrm{sn}}_{n+1}$

${\left(k_4\right)}_n=a(3\mathrm{\α}{x}_{n-1}\left(t\right)+{\left(k_3\right)}_{n-1})-b{(\mathrm{\α}{x}_{n-1}\left(t\right)-\frac{\sqrt{2}}{3}{\left(k_2\right)}_{n-1}+\frac{2+\sqrt{2}}{3}{\left(k_3\right)}_{n-1})}^3+{\mathrm{sn}}_{n+1}$

Wherein, x_nT () is the n order derivative of x (t), sn_n+1It is the value at t=0 for the n-1 order derivative of s (t), sn_n+1It is s Value at t=0 for the n+1 order derivative of (t), n=0,1 ..., n-1；Obtain x₁(t), x₂(t) ..., x_n+1The value of (t)；

Controller is to x₁(t), x₂(t) ..., x_n+1T () is integrated, obtain x (t), and obtains x (t) at one layer at random altogether Shake model and two layers of accidental resonance model composition the double-deck stochastic system generation accidental resonance moment time in optimal detection moment T1, optimum transient motion acceleration alpha 1, and determine the noise d1 corresponding to t1 and α 1；

Controller utilizes formulaCalculate the letter of double-deck stochastic resonance system output Make an uproar ratio；Wherein, △ u=a²/4b；Obtain m²Individual output signal-to-noise ratio ${\mathrm{snr}}_{\mathrm{thre}1},{\mathrm{snr}}_{\mathrm{thre}1},\·\·\·,{\mathrm{snr}}_{{\mathrm{threm}}^2};$

(6-5) controller utilizes formulaCalculate kth group pivoting angle data institute right Output signal-to-noise ratio error qe answered_k, wherein, k=1 ..., m²；

Controller calculates and meets qe_kNumber m of≤5% output signal-to-noise ratio error₁；Controller calculates and meets qe_k＞ 5% Output signal-to-noise ratio error number m₂；

If (6-6)Then the fresh judgement of sample made by controller；

IfThen the stale judgement of sample made by controller；

Otherwise, return to step (6-3-1), again detects to sample and carries out data processing.

Preferably, being equipped with motor in container below each vertical core, each positioning electric magnet respectively with each electricity The vertical rotating shaft of machine is connected, and positioning electric magnet is provided with keeper, and keeper upper end offers M shape groove, metal column Lower end is provided with the M shape projection corresponding with M shape groove, and each motor is electrically connected with the controller；

Step (6-3-2) is replaced by following step:

After metal column inserts a vertical core, controller adjusts laser array output by light intensity adjusting means Detection light, described detection light rises to maximum mat from 0 according to sine curve, then from maximum mat according to sine curve Drop to 0；In detection process, controller controls the rotating shaft of the corresponding motor of vertical core inserted with metal column to drive sample carrier In disc spins 1 to 2 week, spectrogrph obtains detection signal spect (t).

Preferably, the thickness of described lamellar meat is 26 to 68mm.

Preferably, the incident angle of light emitting head is 15 to 60 degree.

Preferably, the span of mat is 98 luxs to 210 luxs.

Therefore, the invention has the following beneficial effects: (1) detection speed is fast；(2) test point is more, detection data can Higher by property and precision.

Brief description

Fig. 1 is a kind of structural representation of the present invention；

Fig. 2 is a kind of structural representation of the sample tray of the present invention；

Fig. 3 is a kind of structural representation of metal column, vertical core, motor, positioning electric magnet and the keeper of the present invention；

Fig. 4 is a kind of theory diagram of embodiments of the invention 1；

Fig. 5 is the Strength Changes schematic diagram of the detection light of the present invention；

Fig. 6 is a kind of flow chart of embodiments of the invention 1.

In figure: spectrogrph 1, light intensity adjusting means 2, container 3, sample tray 4, support 5, light emitting head 6, light-receiving head 7th, vertical core 8, positioning with electric magnet 9, metal column 11, traction with magnet piece 12, power for traction Magnet 13, motor 14, keeper 15, M shape groove 16, M shape projection 17, data collecting card 18, power amplifier 19, laser array 20, Housing Base 21, Spring 23, controller 24.

Specific embodiment

The present invention will be further described with reference to the accompanying drawings and detailed description.

Embodiment 1

Embodiment as shown in Figure 1, Figure 2, Figure 3, Figure 4 is a kind of degree of beef freshness detection means, as shown in figure 4, including Light tight housing, controller 24, laser array 20, spectrogrph 1, light intensity adjusting means 2, as shown in figure 1, in housing The rectangular vessel 3 of upper end open, located at the rectangle sample pallet 4 in container, the support 5 on Housing Base 21, located at On support for sample irradiation light light emitting head 6 and for receive sample reflected light light-receiving head 7；Light intensity is adjusted Regulating device, laser array, light emitting head are sequentially connected electrically, and light-receiving head is electrically connected with spectrogrph；Container and sample tray are equal It is made up of plastic material, in container, is provided with liquid, sample tray is suspended on liquid surface, as shown in figure 1, container bottom is provided with In 16 vertical cores 8 of 4 rank square formation arrangements, in the equal upward opening of each vertical core and vertical core, it is equipped with positioning electric magnet 9, sample Interior in the middle part of pallet it is provided with positioning magnet piece, metal column 11 upper end through sample tray lower surface as shown in Figure 3 and positioning It is connected with magnet piece, positioning electric magnet uses the opposite polarity of the magnetic pole of magnet piece opposite end with positioning；

As shown in Fig. 24 pieces of traction magnet pieces 12 are equipped with each edge of sample tray, on each side of container It is equipped with 4 blocks of power for traction Magnet 13；As shown in figure 4, light intensity adjusting means, spectrogrph, each block of positioning electric magnet and each Block power for traction Magnet is all electrically connected with the controller.

Laser array includes 6 and bundles and single wavelength laser that wavelength is arranged in order, each Single wavelength The wavelength of laser instrument is respectively 630nm, 925nm, 534nm, 780nm, 610nm and 730nm.

As shown in figure 4, light intensity adjusting means includes data collecting card 18 and power amplifier 19, data collecting card sets There is the signal input interface for being electrically connected with the controller, described data collecting card is electrically connected with the input of power amplifier, The outfan of power amplifier and the power electric connection of laser array.

Support is in l shape, including horizon bar and column；Light emitting head is connected with horizon bar by montant respectively with light-receiving head Connect；, all in bar shaped, the pole polarity outside each piece of traction magnet piece is identical for each piece of traction magnet piece.Motor is stepping electricity Machine.

A kind of detection method of degree of beef freshness detection means, comprises the steps:

According to CNS gb/t 5009.44-2003, the volatile salts of the different resting period beef sample of detection Base nitrogen tvb-n value, and obtain and 16 sample detection points corresponding freshness threshold snr respectively_thre1, snr_thre1..., snr_thre16；

Freshness threshold snr_thre1, snr_thre1..., snr_thre16The method obtaining is as follows:

Detect the total volatile basic nitrogen numerical value of the fresh beef just slaughtered, after having detected, beef is put in cold storage plant and deposits Storage, second day, the 3rd day ... take out the total volatile basic nitrogen numerical value that beef continues detection beef, detected every time and all put Enter storage in cold storage plant, when the total volatile basic nitrogen numerical value of certain day sample is exceeded for the first time, then under the sample of this day being adopted State step to be detected, 16 obtaining snr is freshness threshold snr_thre1, snr_thre1..., snr_thre16.

Freshness threshold is related to storage condition, and the beef sample storing in certain temperature, pressure and humidity is entered Freshness threshold snr obtained by row detection_thre1, snr_thre1..., snr_thre16, it is only used for detection and deposit under the same conditions The freshness of the beef of storage.

Before detection, adjust the height of water level in container, make the reflected light that light emitting head is launched permissible after sample reflection Just enter in light-receiving head；

As shown in fig. 6, step 100, sample preparation: choose the thick lamellar meat of 40mm from beef to be detected as to be checked Test sample product；

Step 200, is detected: by controller and light intensity adjusting means, spectrogrph, each block of positioning electric magnet and each Block power for traction Magnet electrically connects, and sample is kept flat on sample tray；

Step 210, controller by each each block of positioning electric magnet and the energising of each block of power for traction Magnet and power-off, Sample tray is controlled to be in bow font movement to each vertical core according to order as shown by the arrows in Figure 1；

Step 220, after metal column inserts a vertical core, controller adjusts laser instrument by light intensity adjusting means The detection light of array output, detection light rises to maximum mat from 0 according to sine curve, then from maximum mat according to sine Curve drops to 0；Detect that rear spectrogrph obtains m²Individual detection signal spect (t)；

Step 300, data processing: controller is to m²Individual detection signal spect (t) all does following data processing:

By detection signal spect (t) input one layer of accidental resonance model:

In, wherein, v (x, t, α) is potential function, and x (t) is Brownian movement Particles Moving lopcus function, and a, b are the normal of setting Number, ξ (t) is outer noise, and d is with the outer noise intensity of 0.01 stepping in the range of [0,1], and n (t) grasps noise for interior,For periodic sinusoidal signal, a is signal amplitude, and f is signal frequency, and t is movement time,For phase place, if

Controller calculates v (x, t, α) for the first derivative of x (t), second dervative and three order derivatives, and makes equation etc. In 0, obtain two layers of accidental resonance model:

Set noise intensity d=0,Spect (t)=0, n (t)=0；It is calculated facing of a Dividing value isThe marginal value of a is substituted in one layer of accidental resonance model, and sets x₀(t)=0, sn₀=0, with quadravalence one layer of accidental resonance model of jade for asking rain Ge Kuta Algorithm for Solving, obtain $x_{n+1}\left(t\right)=x_n\left(t\right)+1/6[{\left(k_1\right)}_n+(2-\sqrt{2}){\left(k_2\right)}_n+(2+\sqrt{2}){\left(k_3\right)}_n+{\left(k_4\right)}_n],$ N=0,1 ..., n-1

And calculate undetermined coefficient:

(k₁)_n=a (α x_n1(t))²-b(αx_n1(t))³+sn_n-1

${\left(k_2\right)}_n=a(\mathrm{\α}{x}_{n-1}\left(t\right)+\frac{{\left(k_1\right)}_{n-1}}{3})-b{(\mathrm{\α}{x}_{n-1}\left(t\right)+\frac{{\left(k_1\right)}_{n-1}}{3})}^3+{\mathrm{sn}}_{n-1}$

${\left(k_3\right)}_n=a({\mathrm{\αx}}_{n-1}\left(t\right)+\frac{{\left(k_2\right)}_{n-1}}{3})-b{({\mathrm{\αx}}_{n-1}\left(t\right)+\frac{\sqrt{2}-1}{3}{\left(k_1\right)}_{n-1}+\frac{2-\sqrt{2}}{3}{\left(k_2\right)}_{n-1})}^3+{\mathrm{sn}}_{n+1}$

${\left(k_4\right)}_n=a(3\mathrm{\α}{x}_{n-1}\left(t\right)+{\left(k_3\right)}_{n-1})-b{(\mathrm{\α}{x}_{n-1}\left(t\right)-\frac{\sqrt{2}}{3}{\left(k_2\right)}_{n-1}+\frac{2+\sqrt{2}}{3}{\left(k_3\right)}_{n-1})}^3+{\mathrm{sn}}_{n+1}$

Wherein, x_nT () is the n order derivative of x (t), sn_n+1It is the value at t=0 for the n-1 order derivative of s (t), sn_n+1It is s Value at t=0 for the n+1 order derivative of (t), n=0,1 ..., n-1；Obtain x₁(t), x₂(t) ..., x_n+1The value of (t)；

Controller is to x₁(t), x₂(t) ..., x_n+1T () is integrated, obtain x (t), and obtains x (t) at one layer at random altogether Shake model and two layers of accidental resonance model composition the double-deck stochastic system generation accidental resonance moment time in optimal detection moment T1, optimum transient motion acceleration alpha 1, and determine t1 and α [the noise d1 corresponding to 1；d₁For one of d value；D be [0, 1] with a function of 0.01 loop cycle stepping in the range of, the value of d and time correlation are it is known that t₁Moment, d₁Determine that ?.

Controller utilizes formulaCalculate the letter of double-deck stochastic resonance system output Make an uproar ratio；Wherein, △ u=a²/4b；Obtain m²Individual output signal-to-noise ratio ${\mathrm{snr}}_1,{\mathrm{snr}}_2,\·\·\·,{\mathrm{snr}}_{m^2};$

Step 400, Error Calculation:

Controller utilizes formulaCalculate corresponding to kth group pivoting angle data Output signal-to-noise ratio error qe_k, wherein, k=1 ..., m²；

Controller calculates and meets qe_kNumber m of≤5% output signal-to-noise ratio error₁；Controller calculates and meets qe_k＞ 5% Output signal-to-noise ratio error number m₂；

Step 500, judges:

IfThen the fresh judgement of sample made by controller；

IfThen the stale judgement of sample made by controller；

Otherwise, return to step 210, again detect to sample and carry out data processing.

M in the present embodiment₁=14,Therefore, the fresh judgement of sample made by controller.

Embodiment 2

In embodiment 2, as shown in figure 3, being provided with motor 14 in the container below vertical core, positioning electric magnet is perpendicular with motor It is connected to rotating shaft, positioning electric magnet is provided with keeper 15, and keeper upper end offers M shape groove 16, under metal column End is provided with the M shape projection 17 corresponding with M shape groove, and motor is provided with the signal output for being electrically connected with the controller Port.Metal column is provided with spring 23.

Step 220 in embodiment 2 is replaced by following step:

After metal column inserts a vertical core, controller adjusts laser array output by light intensity adjusting means Detection light, described detection light rises to maximum mat from 0 according to sine curve, then from maximum mat according to sine curve Drop to 0；In detection process, controller controls the rotating shaft of the motor corresponding with the vertical core that metal column is inserted to drive sample Pallet rotates 1 week, and spectrogrph obtains detection signal spect (t).

Other structures in embodiment 2 and method are partly in the same manner as in Example 1.

It should be understood that the present embodiment is only illustrative of the invention and is not intended to limit the scope of the invention.In addition, it is to be understood that After having read the content of present invention instruction, those skilled in the art can make various changes or modifications to the present invention, these etc. Valency form equally falls within the application appended claims limited range.

Claims (10)

1. a kind of degree of beef freshness detection means, is characterized in that, including light tight housing, controller (24), laser array (20), spectrogrph (1), light intensity adjusting means (2), located at the rectangular vessel (3) of the upper end open in housing, in container Rectangle sample pallet (4), the support (5) on Housing Base (21), on support for sample irradiation light Light emitting head (6) and the light-receiving head (7) for receiving the reflected light of sample；Light intensity adjusting means, laser array, light are sent out Penetrate head to be sequentially connected electrically, light-receiving head is electrically connected with spectrogrph；Container and sample tray are made by non-magnet_conductible material, described appearance It is provided with liquid, described sample tray is suspended on liquid surface, container bottom is provided with m rank square formation several of arrangement and erects in device Hole (8), is equipped with positioning electric magnet (9) in the equal upward opening of each vertical core and vertical core, interior in the middle part of described sample tray set There is positioning magnet piece, metal column (11) upper end through sample tray lower surface is connected with positioning magnet piece, positioning is used Electric magnet and the opposite polarity positioning the magnetic pole with magnet piece opposite end；

Some pieces of traction magnet pieces (12) are equipped with each edge of sample tray, each side of container are equipped with some Block power for traction Magnet (13)；Light intensity adjusting means, spectrogrph, each block of positioning electric magnet and each block of power for traction Magnet are equal It is electrically connected with the controller.

2. degree of beef freshness detection means according to claim 1, is characterized in that, is all provided with the container below each vertical core There is motor (14), each positioning electric magnet is connected with the vertical rotating shaft of each motor respectively, and positioning electric magnet is provided with Keeper (15), keeper upper end offers M shape groove (16), and metal column lower end is provided with corresponding with M shape groove M shape projection (17), each motor is electrically connected with the controller.

3. degree of beef freshness detection means according to claim 1, is characterized in that, described laser array includes 6 bundles Be held together and single wavelength laser that wavelength is arranged in order, the wavelength of each single wavelength laser be respectively 630nm, 925nm, 534nm, 780nm, 610nm and 730nm.

4. degree of beef freshness detection means according to claim 1, is characterized in that, described light intensity adjusting means includes counting According to capture card (18) and power amplifier (19), described data collecting card is provided with the signal input for being electrically connected with the controller Interface, described data collecting card is electrically connected with the input of power amplifier, the outfan of described power amplifier and laser instrument The power electric connection of array.

5. the degree of beef freshness detection means according to claim 1 or 2 or 3 or 4, is characterized in that, support is in l shape, including Horizon bar and column；Light emitting head is connected with horizon bar by montant respectively with light-receiving head；Each piece of traction is equal with magnet piece In bar shaped, the pole polarity outside each piece of traction magnet piece is identical.

6. a kind of detection method of the degree of beef freshness detection means being applied to described in claim 1, is characterized in that, including as follows Step:

(6-1) according to CNS gb/t 5009.44-2003, the volatile salts of the different resting period beef sample of detection Base nitrogen tvb-n value, and obtain and m²Individual sample detection point corresponding freshness threshold snr respectively_threl, snr_threl...,

(6-2) sample preparation: choose lamellar meat from beef to be detected as detected sample；

(6-3) detected: by controller and light intensity adjusting means, spectrogrph, each block of positioning electric magnet and each piece of traction With electric magnet electrical connection, sample is kept flat on sample tray；

(6-3-1) controller is by each each block of positioning electric magnet and each piece of power for traction Magnet energising and power-off, controlling Sample tray is along bow font movement to each vertical core；

(6-3-2) after metal column inserts a vertical core, controller adjusts laser array by light intensity adjusting means The detection light of output, detection light rises to maximum mat from 0 according to sine curve, then from maximum mat according to sine curve Drop to 0；Detect that rear spectrogrph obtains m²Individual detection signal spect (t)；

(6-4) controller is to m²Individual detection signal spect (t) all does following data processing:

By detection signal spect (t) input one layer of accidental resonance model:

In, wherein, v (x, t, α) is potential function, and x (t) is Brownian movement Particles Moving lopcus function, and a, b are the constant setting, ξ T () is outer noise, d is with the outer noise intensity of 0.01 stepping in the range of [0,1], and n (t) grasps noise for interior,For periodic sinusoidal signal, a is signal amplitude, and f is signal frequency, and t is movement time,For phase place, if

Controller calculates v (x, t, α) for the first derivative of x, second dervative and three order derivatives, and makes equation be equal to 0, obtains Two layers of accidental resonance model:

Set noise intensity d=0,Spect (t)=0, n (t)=0；It is calculated the critical of a It is worth and beThe marginal value of a is substituted in one layer of accidental resonance model, and sets x₀(t)=0, sn₀=0, with quadravalence one layer of accidental resonance model of jade for asking rain Ge Kuta Algorithm for Solving, obtainN=0,1 ..., n-1

Wherein undetermined coefficient:

(k₁)_n=a (α x_n-1(f))²-b(αx_n-1(f))³+sn_n-1

${\left(k_2\right)}_n=a\left({\mathrm{\αx}}_{n-1}\right(t)+\frac{{\left(k_1\right)}_{n-1}}{3})-b{\left({\mathrm{\αx}}_{n-1}\right(t)+\frac{{\left(k_1\right)}_{n-1}}{3})}^3+{\mathrm{sn}}_{n-1}$

${\left(k_3\right)}_n=a\left({\mathrm{\αx}}_{n-1}\right(t)+\frac{{\left(k_2\right)}_{n-1}}{3})-b{\left({\mathrm{\αx}}_{n-1}\right(t)+\frac{\sqrt{2}-1}{3}{\left(k_1\right)}_{n-1}+\frac{2-\sqrt{2}}{3}{\left(k_2\right)}_{n-1})}^3+{\mathrm{sn}}_{n+1}$

${\left(k_4\right)}_n=a\left(3{\mathrm{\αx}}_{n-1}\right(t)+{\left(k_3\right)}_{n-1})-b{\left({\mathrm{\αx}}_{n-1}\right(t)-\frac{\sqrt{2}}{3}{\left(k_2\right)}_{n-1}+\frac{2+\sqrt{2}}{3}{\left(k_3\right)}_{n-1})}^3+{\mathrm{sn}}_{n+1}$

Wherein, x_nT () is the n order derivative of x (t), sn_n-1It is the value at f=0 for the n-1 order derivative of s (t), sn_n+1It is the n+ of s (t) Value at t=0 for 1 order derivative, n=0,1 ..., n-1；Obtain x₁(t), x₂(t) ..., x_n+1The value of (t)；

Controller is to x₁(t), x₂(t) ..., x_n+1T () is integrated, obtain x (t), and obtains x (t) in one layer of accidental resonance mould The double-deck stochastic system of type and two layers of accidental resonance model composition produces the optimal detection moment time t1 in accidental resonance moment, Excellent transient motion acceleration alpha 1, and determine the noise d1 corresponding to t1 and α 1；

Controller utilizes formulaCalculate the signal to noise ratio of double-deck stochastic resonance system output； Wherein, δ u=a²/4b；Obtain m²Individual output signal-to-noise ratio snr_threl, snr_thre

(6-5) controller utilizes formulaCalculate corresponding to kth group pivoting angle data Output signal-to-noise ratio error qe_k, wherein, k=1 ..., m²；

Controller calculates and meets qe_kNumber m of≤5% output signal-to-noise ratio error₁；Controller calculates and meets qe_k＞'s 5% is defeated Go out number m of noise ratio error₂；

If (6-6)Then the fresh judgement of sample made by controller；

IfThen the stale judgement of sample made by controller；

Otherwise, return to step (6-3-1), again detects to sample and carries out data processing.

7. the detection method of degree of beef freshness detection means according to claim 6, the container below each vertical core described Inside it is equipped with motor, each positioning electric magnet is connected with the vertical rotating shaft of each motor respectively, and positioning electric magnet sets There is keeper, keeper upper end offers M shape groove, metal column lower end is provided with the M shape corresponding with M shape groove Projection, each motor is electrically connected with the controller；It is characterized in that,

Step (6-3-2) is replaced by following step:

After metal column inserts a vertical core, controller adjusts the inspection of laser array output by light intensity adjusting means Light-metering, described detection light rises to maximum mat from 0 according to sine curve, then declines according to sine curve from maximum mat To 0；In detection process, controller controls the rotating shaft of the corresponding motor of vertical core inserted with metal column to drive sample carrier to spiral Turned for 1 to 2 week, spectrogrph obtains detection signal spect (t).

8. the detection method of degree of beef freshness detection means according to claim 6, is characterized in that, the thickness of described lamellar meat Spend for 26 to 68mm.

9. the detection method of degree of beef freshness detection means according to claim 6, is characterized in that, the incidence of light emitting head Angle is 15 to 60 degree.

10. the detection method of the degree of beef freshness detection means according to claim 6 or 7 or 8 or 9, is characterized in that, mat Span be 98 luxs to 210 luxs.