KR101483002B1 - Method for measuring sun-dried salt using analyzing disused ingredients and water in sun-driedsalt - Google Patents

Abstract

The present invention relates to a method for measuring the quality of sun-salt by measuring the amount of insoluble matter and moisture in the sun-salt measured using a reflection spectrum value by irradiation of near-infrared rays without destroying the sun-salt. According to the present invention, It is possible to quickly and accurately analyze the amount of insolubles contained in the salt in a non-destructive manner. By measuring the quality of the salt in accordance with the results of this analysis, And to allow the supplier to determine the release date according to the degree of aging of the sun salt.

Description

Technical Field [0001] The present invention relates to a method for measuring the quality of sun-dried salt by using an insoluble component in a salt solution and a method for measuring the quality of the salt,

The present invention relates to a method for measuring the quality of sun-salt, and more particularly, to a method for measuring the quality of sun-salt by measuring the amount of insoluble matter and moisture in the sun-salt measured using the reflection spectrum value by irradiation of near- .

It is made by evaporating water from the wind and sunlight or by evaporating seawater from the plant by using a heating evaporator. It is widely used to make kimchi kimchi and to immerse various kinds of soup in everyday life .

There are a lot of minerals in the body of the sun salt. Domestic sun salts have a lot of minerals in comparison with foreign sun salts such as China and Australia, and the domestic sun salt produced in the tidal flats has a sodium chloride content of 80-85% , Which is superior to those of Australia and China (85-95%). Domestic sun salt has a low sodium chloride content and a lot of minerals. In addition, the results of various studies show that when the salt is dissolved in water, the salt of foreign salt is acidic, whereas the salt of domestic salt is alkaline. Especially, when using traditional salt such as salted or kimchi, The results are excellent. In addition, Korean astringent salt has the effect of alleviating adult diseases such as diabetes and arteriosclerosis, whereas the study shows that processed sun-dried salt oxidizes blood in the human body and exacerbates hyperlipemia or arteriosclerosis. Therefore, More and more.

However, the naturally dried sun salt contains a harmful ingredient, which is a bitter component containing about 25% of sun salt, its main components being magnesium (Mg), potassium (K) , Sulfur (S) and zinc (Zn) are the major constituents and exist in the form of magnesium chloride (MgCl ₂ ), magnesium sulfate (MgSO ₄ ) and calcium sulfate (CaSO ₄ ). The content of sulfur-related substances in sun salts ranges from about 4,000 to 7,000 ppm, which is the main cause of bitter taste. In addition to having a bitter taste, jars have a relatively irritating taste, which not only deteriorates the taste of the food but also has a strong detoxifying property.

In Korea, traditionally, a method of stacking sun-dried salt bags and leaving them for 1-2 years or putting sun-dried salt in a perforated jar for 2-3 years is used to dissolve the hygroscopic water. It is used for food. This method has a disadvantage that it takes a lot of time, and it is known that not only delaying distribution time but also additional labor and equipment due to storage, especially the removal rate of the wastewater is also not so high.

Therefore, the establishment of a method for completely removing the wastewater can be accomplished not only by improving the quality of the salt, but also by shortening the period of distribution, thereby reducing the production cost.

In addition, there is a need for a technique for rapidly analyzing the degree of removal of the insoluble component, which is an insoluble component contained in the sun-salt. Particularly, it is possible to determine the release date of sun salt according to the place of production, the manufacturing method, the season and the aging period through such an analysis method, and to provide a method for measuring the quality of sun salt, which can provide an objective rating index for commercial sun- However, there is no technique to measure the quality of the sun - salt that can be shown objectively and numerically at present.

Accordingly, a problem to be solved by the present invention is to quickly measure the amount of insoluble components and water contained in the sun salt by using the spectral value after the near infrared ray is irradiated without destroying the sun salt, and thereby measuring the quality of the sun salt .

In order to solve the above problems,

(a) obtaining a reflection spectrum by irradiating near-infrared rays to an insoluble component containing sulfuric acid ions and magnesium and a salt having a known moisture content;

(b) obtaining a mathematical standard calibration equation from the correlation between the reflection spectrum of the near-infrared region obtained by the step and the insoluble component and moisture content in the salt;

(c) irradiating the measured salt with near-infrared rays to obtain a reflection spectrum; And

(d) substituting the reflection spectrum of the near-infrared region obtained from the step (c) into the mathematical standard calibration equation to obtain the content and water content of the insoluble component contained in the salt to be measured; And a method for measuring the quality of salt to be used.

According to an embodiment of the present invention, the step (b) divides the reflection spectrum of the obtained near-infrared region and uses the differential spectral spectrum to calculate a mathematical standard calibration equation from the correlation between the insoluble component and the water content in the salt. (D) is obtained by dividing a reflection spectrum of the near-infrared region obtained from the step (c) and substituting it into the mathematical standard calibration equation using a differential spectral spectrum to determine the insolubility Component content and water content can be obtained.

According to an embodiment of the present invention, the derivative includes a first derivative, a second derivative, or both, wherein the segment of the first derivative or the second derivative is 5 units or 7 units, and smooth ) Can be 3, 7 or 9.

According to an embodiment of the present invention, the step (b) comprises: obtaining a mathematical standard calibration equation from the correlation between the insoluble component and the moisture content in the salt after multipath scattering correction of the differential spectrum; ) Can calculate the content and moisture content of the insoluble component contained in the salt to be measured by substituting the differential spectrum for the multiple scattering correction into the mathematical standard calibration equation.

According to another embodiment of the present invention, the near-infrared ray may have a wavelength of 950-1650 nm.

According to another embodiment of the present invention, the derivative includes a first derivative, a second derivative, or all of them, wherein the segment of the first derivative or the second derivative is 5 units or 7 units, smooth may be 3, 7, or 9.

Near-Infrared Spectroscopy (NIRS) is a technique that utilizes the NIR absorption characteristics of a sample to predict the components of interest. It was applied for the first time by Carl Norris of the US Department of Agriculture in the early 1960s, , And feeds as well as chemical, biochemical, cosmetic, medical, petrochemical, pharmaceutical, polymer, paper and textile fields.

Quantitative analysis uses Beer's law to obtain a linear equation with the transmittance and reflectance of the sample to be measured. The sample is collected and selected, and the scattering effect of the irradiated light on the sample is corrected. And then apply it to routine analysis after verifying it. And NIR is not absolute quantitative analysis but relative quantitative analysis. It can measure not only stoichiometry but also general physical quantity.

Near infrared rays exist at 700-2,500 nm between the branch light and the medium infrared light and have lower energy than visible light and higher energy than middle infrared light. Near-infrared spectroscopy exploits the fact that most natural products absorb near-infrared radiation at specific regions or wavelengths. Especially NH, O-H and C-H bonds strongly absorb near-infrared radiation while other molecules are weakly absorbed. Absorption of near-infrared rays is mainly due to the coupling band and harmonics of fundamental molecular vibration energy of N-H, O-H and C-H bonds present in the mid-infrared. The absorbance is much weaker in near infrared rays appearing as a bond band and harmonics. The near infrared (NIR) band is mainly used for quantitative analysis of samples, and the middle infrared (MIR) band is used for quantitative analysis.

Since the absorbance energy of near infrared rays is very small, that is, about 10-1,000 times as much as the fundamental molecular vibration energy of the functional group derived from the medium infrared ray, it is convenient to measure it as it is without requiring pretreatment like the middle infrared ray. In the near-infrared region, absorption by moisture is very weak, and whole water inspections are possible. Information represented by functional groups such as CH, NH, and OH constituting the organic matter is compressed in the near-infrared region to obtain physicochemical characteristics information . In addition, when a specific wavelength that can represent the state of the sample is determined, the spectroscopic analysis method is easier to construct the quality evaluation system than the other non-destructive testing methods, does not require skilled techniques in the analysis, is easy to interpret the results, There is an advantage that the system can be configured.

In addition, by comparing the absorbance obtained at a specific wavelength using a near infrared ray spectrometer (NIR), the degree of the guard can be roughly confirmed, and the sample can be analyzed quickly without a separate pretreatment. It is possible to minimize the pretreatment (dissolution, heating, homogenization, etc.) of the sample by analyzing using the light in the near-infrared region, and it is possible to confirm the variation of each spectrum by processing using the mathematical function of the spectrum (water treatment) have. By way of example, the differential treatment of the spectrum makes it easier to distinguish the difference in absorption spectrum for each sample by making more correction for the baseline and more changes to the variation.

In the context of the present invention, the term "scatter correction" means to compensate for nonlinear functions that distort the correlation between spectra and empirical values. The scatter correction method is as follows. (1) Standard normal variant (SNV): The particle size effect is reduced by shrinking from the baseline to each spectrum of the standard deviation. (2) Detrend: Eliminates linear or quadratic curvature from each spectrum. (3) Standard MSC (Multiplicative scatter correction): Each spectrum is corrected using the average spectrum. (4) Inverse MSC: Used only for Infratec devices.

The changes in the surrounding environment (illumination, temperature, etc.) and light scattering on the surface of the object, the size of the object, the distance between the object and the sensor, and the noise of the sensor affect the measured optical spectrum . Furthermore, it is not a laboratory experiment, but it is more influential in measuring the optical spectrum in real time at the agricultural screening site. Therefore, this influence affects the spectrum used to determine the optical characteristics, causing spectral variations irrespective of the information of the internal quality, causing an error in the prediction of the internal quality measurement, thereby affecting the performance of the quality determination developed .

Spectral preprocessing is performed to correct errors due to such spectral variations. Spectral preprocessing is a very basic and important technique for eliminating these optical measurement noises and reducing errors due to their effects, and is used to characterize more stable optical spectra.

The main methods of spectral preprocessing include smoothing, MSC, SNV, average and maximum values, three kinds of normalization using a range of values, Savitzky-Golay and Norris Gap methods using first and second derivative characteristics . Among them, the smoothing method is used to remove the noise of the spectrum measuring device, and the first and second differentials are used to remove the movement of the baseline caused by the difference in the optical path or the change of the measurement environment, or to emphasize the spectral characteristics of the minute component do. And MSC and SNV are used to eliminate the effects of light scattering in spectral measurements. The Norris Gap differential is similar to the Savitzky-Golay differential but can be used to adjust the gap size.

The reflection spectrum obtained in the present invention includes a step of pretreatment to reduce the influence by the scattering effect.

According to a preferred embodiment of the present invention, the present invention further comprises a pre-processing step of differentiating the obtained reflection spectrum into a predetermined order, multiplicative scatter correction or both.

According to a preferred embodiment of the present invention, when the present invention is subjected to a pre-treatment step through a fine powder, the derivative includes a first derivative, a second derivative, or both.

According to a preferred embodiment of the present invention, when the present invention is subjected to a pretreatment step through a fine powder, the segment of the first derivative or the second derivative is 5 units or 7 units, and the smooth is 3, 7 Or 9.

The present invention can use the PLSR (Partial Least Squares Regression) method in the multivariate regression analysis to obtain a standard calibration equation.

According to an embodiment of the present invention, the salt may be sodium salt.

According to another embodiment of the present invention, in the step (b), the quality of the salt may be determined from the first grade to the third grade according to the measured water content and the sulfate ion content of the salt.

According to another embodiment of the present invention, when the content of water is 1-5% by weight and the content of sulfate ion is 0.05-0.1% by weight, it is grade 1, and when the content of water exceeds 5% by weight and 10% %, And the content of the water is more than 10% by weight and not more than 15% by weight, and the content of the sulfate ion is not more than 0.2% by weight, and when the content of the sulfate ion is more than 0.1% By weight and less than 0.5% by weight, and it is judged to be outside the grade when it is out of the range of 1 to 3.

Even if the content of the water and the content of the sulfate ion are included in the first grade, the magnesium content is determined to be in the range of 100-5,000 mg / L, and when the content of the calcium exceeds the upper limit in the range of 500-1,000 mg / L And the magnesium content is 5,000-8,000 mg / L and the calcium content exceeds the upper limit of 1,000-2,000 mg / L, even if the content of water and the content of sulfate ion are included in the second grade. If the content of water and the content of sulfate ion are included in grade 3, the content of magnesium is 8,000-10,000 mg / L and the content of calcium exceeds the upper limit of 2,000-3,000 mg / L. .

According to the present invention, it is possible to quickly and accurately analyze the amount of the insoluble components contained in the salt of the sun by the near-infrared rays using the near-infrared rays, and the quality of the salt is measured by these analysis results, Each of the various kinds of sun-dried salt of each quality can select the desired quality sun-salt, and the supplier can determine the shipment time according to the degree of aging of the sun-salt.

FIG. 1 is an image (× 100) taken by SEM (scanning electron micrographs) of 2009, 2008 and 2005 sun-dried SEM. A is the image of 2009, B is 2008, and C is 2005.
FIG. 2A shows the result of measuring the raw spectrum in the range of 950-1,650 nm for the salt samples 1, 2, 3 and 4 in the untreated state.
FIG. 2B is a spectral result obtained by changing the original spectrum using the S. Golay first order differential function and Smoothing 3 (in 5 nm steps). FIG. 2B is a graph showing the spectrum of salt obtained by using a near infrared ray spectrometer (NIR) and then analyzing it by a math-treatment. In the graph, the spectra of the spectra corresponding to the wavelengths of about 1150 nm and 1350 nm I could confirm the mutation. In other words, it was found that the variation of the absorbance corresponds to the change of the guard interval with time for the salt in a specific wavelength band.
FIG. 2C is a spectrum comparison result in which the spectral results of FIG. 2B are further enlarged. Sample 4 was found to have a distinct spectrum from the other three natural salt samples. It was found that samples 1, 2 and 3 showed the degree of absorption of the spectral change due to the elimination of the water, and the absorbance decreased with time.
FIG. 3A is a raw spectrum measurement chart of the sun-salt without water treatment. FIG. That is, it is the raw spectrum result of the sample sampled over time while chemically treating the wastewater. Samples were separated at intervals of about 30 seconds according to the passage of time, and the progress of the waters was obtained as a spectrum.
FIG. 3B is a graph showing a calibration curve of the sun-salt without water treatment and without differential. This is a graph of the result of applying the calibration equation to the raw spectrum and applying it. Overall tendency was confirmed, but slope was relatively low.
FIG. 3C is a spectrum measurement chart of a saline solution subjected to SNV water treatment. The primer spectrum was subjected to water treatment to enhance the baseline correction and the ability to differentiate at each wavelength. SNV function was applied for scatter correction of spectrum.
FIG. 3D is a spec-drum measurement chart in which a first-order differential is applied after SNV water treatment. The S. Golay function was used as the first derivative.
FIG. 3E is a graph showing a calibration curve in which a first derivative is applied after SNV water treatment. SNV function and the calibration equation based on the first derivative. R-Square has 0.872 in the calibration set and 0.619 in the verification set.
FIG. 3F is a graph of a calibration curve (seven segments, applied as three sample groups) in three groups with seven segments. For the verification, we divided the samples into three groups and prepared a calibration equation. As a small sample, we divided the samples into groups rather than individual samples.
3G is a spectrum obtained by correcting the spectrum with S.Golay first order differential and Smoothing 7. The smoothing function was used to prevent spectrum noise from spreading between spectral gaps due to segment application.
3H is a calibration graph of Norris first order differential, gap 3 and smoothing 7 (three sample groups). The results are obtained by calibrating the spectra with S. Golay first order differential and Smoothing 7.
3I is a spectrum measurement chart obtained by applying the Smooth function of the Norris differential function.
3J is an enlarged view of the spectrum measurement obtained by applying the Smooth function of the Norris differential function. The data of FIGS. 3A to 3I are prepared in six times. As a result of the various water treatment operations (differential, scatter function, segment, gap application, Smooth function) of the NIR, As shown in FIG. 3J, it is confirmed that the NIR spectrometer can be applied to the analysis of waters.
Figure 4A is a raw spectrum measurement of 46 samples.
4B is a spectrum measurement chart using S.Golay differential and Smoothing 9.
Figure 4c is a calibration graph of calcium.
4D is a graph showing a calibration curve of magnesium.
4E is a graph showing a calibration curve of sulfate ion.
Figure 4f is a calibration graph of chlorine.
5A is a time-series analysis chart of moisture in the salt of the sun, FIG. 5A is a result of measuring a raw spectrum in a state of no water treatment, FIG. 5B is a spectrum measurement chart of the sun- FIG. 5D is a graph showing the calibration curve of the water. FIG.

Hereinafter, the present invention will be described in more detail with reference to preferred embodiments. It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims. It will be clear to those who have knowledge.

<Examples>

Unless otherwise stated, the solids / solids are (wt / wt) parts or percent, the solids / liquids are (wt / vol) parts or%, and the liquid / liquid is (vol / vol) parts or%.

Materials and methods

The samples used in this experiment were obtained from April 2009 in Hae Tae - dong, Shin - myeon, Shinan - gun, Jeollanam - do. The annual production of sun saliva was estimated by purchasing the samples of the same sun saliva produced in Haeda - dong area, Sin - nyeon - myeon, Shinan - gun, Chonnam. The samples were subjected to the same conditions using Burrows (USA).

Analysis of sun saliva (Korean Standard Specification Standard for Analysis of Sun-salt Quality Criteria, Korea Food & Drug Administration Notice No. 2008-6)

(1) Sample preparation

The sieves having a sample particle size of 0.84 mm were passed through and crushed to such an extent that they did not pass through a sieve of 0.177 mm and mixed well.

(2) Sodium chloride

Food Standards 4. Standards and Specifications for Foodstuffs 2015 Analysis was conducted in accordance with the method of salt preparation test (Korean Food and Drug Administration, Food Standards Codex, 2005, Korean Foods Industry Association, Seoul, Korea). About 1 g of sodium chloride was precisely taken to 500 ml, and then filtered. 10 ml of potassium chloride solution was added to 2-3 drops of the solution, which was then titrated with a 0.02 N silver nitrate solution.

Sodium chloride = (b / a) x f x 5.85 (w / w%, w / v%)

a: Sample amount (g, ml)

b: Amount (ml) of 0.02 N silver nitrate solution consumed in the titration;

f: Potency of 0.02 N silver nitrate solution

(3) Total chlorine

Take exactly 25 ml of the sample solution from the insoluble matter and make it neutral. Transfer it to a 250-ml volumetric flask and dilute to the scale. 25 ml of this solution was precisely taken in a beaker, 1-2 drops of 10% potassium chromate solution were added, titrated until a red precipitate appeared with 0.1 N silver nitrate solution, and total chlorine was calculated according to the following formula.

Total chlorine (Cl) (%) = (consumption of 0.1 N silver nitrate solution (mL) x 35.45 x f) / sample weight (g)

f: concentration coefficient of 0.1 N silver nitrate solution

When the sample solution is alkaline, it is neutralized with nitric acid and when acidic, it is neutralized with ammonia water. Approximately 17 g of silver nitrate was dissolved in 1,000 ml of water, and the solution was titrated with potassium chromate as a indicator and 0.1 N sodium chloride standard solution to determine its concentration coefficient. Thus, a 0.1 N silver nitrate solution was prepared.

(4) Moisture

The test was carried out according to the following mineral analysis method (Food Code, paragraph 10. General Testing Methods 1. General Component Test Method 1) water content).

(5) Insoluble matter

10 g of the sample is precisely weighed, placed in a beaker, dissolved in about 200 ml of water, preliminarily dried at 100-110 ° C, filtered through a glass filter, and sufficiently washed with water until no chlorine ions come out of the solution. The washed glass filter was dried at 100-110 ° C and weighed to determine the residue. This filtrate was transferred to a measuring flask (250 ml) and diluted to the scale, and used as a sample solution for the total chlorine and sulfate ion test.

(6) Sulfate ion

25 ml of the sample solution in an insoluble matter was precisely put into a beaker, acidified by adding diluted hydrochloric acid to 50 ml, boiled, and then slowly added with 5% barium chloride solution and heated in a water bath. The mixture was heated for about 2 hours and filtered through a filter paper for quantification. The residue was washed thoroughly with hot water until no chlorine reaction occurred and the residue was dried with filter paper. It was put into a crucible, carbonized, heat treated, and then cooled. After cooling, sulfate ion was calculated according to the following formula.

Sulfate ion (%) = (weight of residue (g) x 0.4115 / weight of sample (g)) x 100

(7) Quadrant

2-5 g of the sample was dissolved in 100 ml of water, 10 ml of hydrochloric acid was added, and the mixture was heated on a hot plate for 1 hour. Cool to room temperature, filter with filter paper (5C), and wash the insoluble matter with water until no chlorine ions are detected. The filter paper and the insoluble matter were transferred to a preheated crucible (cooled after being heated at 850 ° C), and the mixture was stirred at 850 ° C. The crucible was cooled to room temperature from a desiccator and the crucible was weighed to calculate the quartic content.

(8) Chromaticity

The sample was placed in a cylindrical container (DiaxH, 41 × 12.5 mm) with a lid, and a container filled with a sample was placed in a grooved black pad into which a cylindrical container could be inserted, and a colorimeter (Minolta, CR 200, JAP L "," a "and" b "were measured using a light projection tube (CRA33).

(9) Sulfur

Sulfur was analyzed with a carbon ion analyzer (Carbon / Sulfur Determinator CS-600, Made in USA).

(10) Mineral Analysis

The distilled water used in this study was water purified to a level of 18.2 M? By Milli-Q ultrapure water purification system (Millipore Co., Molsheim, FRANCE) Hydrochloric acid (Dongwoo Fine Chem Co., Ltd., Iksan) used for the standard solution was purchased from Electronic grade, and each standard stock solution was mixed with AccuStandard (USA) The concentration of mercury in the HNO3 solution was measured using a HNO3 solution containing 1000 ppm of HNO3 and diluted with 1.2 N HCl solution to prepare a calibration curve. Mercury content was measured with a Combustion gold amalgamationmethod using a Mercury analyzer (AMA254, Milestonesrl, Italy). ICP-AES (Activa, HORI BA Jobin-Yvon, Longjumeau, France) conditions are shown below.

RF power 1000 W

Nebulizer gas flow 0.7 - 0.8 L / min

Plasma gas flow rate 12 L / min

Sheath gas flow 0.3 L / min

Nebulizer Pressure 2.7 - 3.5 bar (for meinhard type)

Pump speed 20 times / minute

Wavelength (nm)

- Zn 213.856 / P 214.914 / Mn 259.373 / Fe 259.940 / Mg 279.079 / Ca 317.933 / Cu 324.754 / Na 588.995 / K 766.490 /

- As 188.983 / Pb 220.353 / Cd 226.502

(11) SEM photographing

Microstructures were obtained by magnification of 100, 500 and 1000 times with scanning electron microscope (S2380N, Hitachi, Japan).

(12) Image measurement

An image measuring instrument (CV-M77, IAI, Japan) was used and the measurement program was a sensor eye IA (Korea).

(13) Condition of pretreatment

Experiments were carried out using cleaning, dehydration and humidification methods for this experiment. The washings were analyzed for the quality of salinity after instant cleaning with 10, 20, 25 and 30% NaCl and distilled water, respectively. The dehydration treatment was carried out using a low-speed centrifuge (Model: Mini Spin Extractor, W-100T, Korea) at 1,800 rpm for 3-9 min treatment time. The humidification treatment was performed in a humidified range of 60 to 180 minutes after the saturated water vapor was put into a closed container.

(14) Weight change

The weight change was measured using an electronic balance (Satorius 420, GER). The weight change was converted into the following equation.

W = (FW / IW) x100

W: Weight change (%)

FW: Weight after storage (g)

IW: Initial weight (g)

(15) Sensory evaluation and statistical processing

The sensory test was carried out by ten researchers' panels. The degree of discoloration and occurrence of disturbance were examined. The statistical significance was analyzed using ANOVA ANOVA and Duncan 's multivariate test using SAS program.

(16) NIR analysis

The spectra of the sun salts were measured in the range of 950-1,650 nm using a Diodearray 7200 analyzer. The prediction method of the result was analyzed using Unscrambler. In the correlation analysis, the primary spectrum and the first and second differential spectrums were used, which varied the gap and the smoothing interval. The preprocessing spectrum and preprocessing Respectively, were used.

The definitions of the terms shown in Figs. 2A to 5D are as follows.

Slope: the slope between the predicted value and the measured value

Offset: Point of the regression line intersecting the Y coordinate (predicted value)

RMSE: Cal. Set and Val. As an average difference between the measured and predicted values for the Set, the RMSE can be interpreted as the mean error of the model and has the same units as the original response.

R-Square: The square of the correlation coefficient between the measured value and the predicted value measured by the quality of the model in the calibration model. This value is always between 0 and 1, and higher is better.

Calibration set: The set of samples used to create the NIR calibration equation

Validation set: A set of samples used to verify the NIR calibration equation

Experiment result

(1) The quality of the solar salt depending on the production time

The difference of contents of NaCl, insoluble matter, sulfate ion and quartz was relatively large depending on the production period, and there were many differences in content depending on the production region. In addition, KFDA and Korean industry standard quality standard insolubles and quarts content were partially exceeded, and water content exceeded some standard. The color difference of the solar salt is also relatively large. The quality characteristics of the sun-salt according to the production time are shown in Table 1 below, and the colors of the seasonal sun-dried salt are shown in Table 2 below (unit: standard deviation% (dry basis)).

(2) By aging degree (by production year) Quality of sun salt

As a result of the analysis of the quality of the sun salt according to the year of production, NaCl and moisture content were lowered, and the content of insoluble matter, total chlorine, sulfate ion and quadrature was increased.

In addition, the intensity of milky white color of sun - salt decreased. As a result of comparing the crystallization structure of the solar salt crystals, it was confirmed that the minute space formation occurred for the long - stored solar salt crystals, which is caused by the elution of the solutes in the crystals. The results for the quality and color of the samples by production year are shown in Tables 3, 4 and 1 (unit: standard deviation% (dry basis)).

(3) NIR measurement test results

(Table 5, unit: mg / L) was measured by dividing the difference in the content of insoluble matter (insoluble matter) by NIR. The samples were 1. Sun-hatched salmon in June 2010, 2. Aged sun-salted salmon in 3 rd year,

division calcium magnesium Sulfate ion Goat moisture One 2512.00 9540.17 309.51 50819.78 12.54 2 3074.90 8860.67 192.60 51776.33 8.31 3 2140.18 5833.80 136.11 59239.30 6.89 4 301.93 118.86 14.95 61336.73 4.95

In addition, for water treatment, the original spectrum was changed using a general S. Golay first differential function and Smoothing 3 in 5 nm units, and the differential function also showed the difference with baseline stability (Figs. 2a to 2c ). As a result, it was confirmed that NIR measurement could be used for quality analysis and management of NIR. In order to separate the sample, we also used the S. Golay function, and we could see that it was separated at several wavelengths. In addition, we confirmed the relationship with insoluble content (bitterness) in various regions, and it could be expected that more accurate value could be obtained by increasing the representative number (population).

5A to 5D are the results of measuring the changes in moisture with respect to each sample by NIR, and SNV and S.Golay first order differential functions were used for water treatment. It was confirmed that measurement was possible without pretreatment for each sample, and it was confirmed that there is a correlation between spectral change and moisture content. Therefore, the moisture content in the sample can be measured according to the change in spectrum.

In this way, the amount of insoluble matter and moisture can be directly measured without any additional pretreatment, and the quality grade of the salt can be determined accordingly.

(4) Secondary analysis

The minerals of 26 samples were analyzed according to the insoluble content (Figs. 3A to 3J). The results are shown in Table 6 below.

(9) Third analysis

The number of samples was increased to analyze the minerals contained in a total of 46 samples (Figs. 4A to 4F). The slope between the predicted value and the measured value is shown, and the offset refers to the point of the regression line intersecting with the Y coordinate (predicted value). Set and Val. Set is to measure the mean difference between the measured and predicted values, and the RMSE can be interpreted as the mean error of the model and has the same units as the original response value. In addition, R-Square is calculated as the square of the number of the correlation between the measured value and the predicted value by the measurement of the quality of the model in the calibration model. This value is always between 0 and 1, and the higher is better. The calibration set refers to the set of samples used to create the NIR calibration equation and the verification set refers to the set of samples used to verify the NIR calibration equation.

The results of analyzing the minerals (magnesium, sulfate ions) contained in the total of 46 samples by increasing the number of samples are shown in Tables 7 to 9 below.

The correlation between the R-square of Mg and sulfate ion compounds was as high as 0.92 and 0.85, and the R-square of Ca and Cl compounds showed low correlation with 0.004956 and 0.051898, respectively. Respectively. Also, referring to the spectral change, it can be seen that the variation depending on the insoluble content has an influence, and the correlation is estimated to be about 75% or more. The primary analysis data with increasing insoluble matter difference showed the same tendency in the case of the second and third cases which were measured by increasing the number of samples. In the first case, the difference in insoluble matter content was large and representative samples were analyzed The results of analysis through 1, 2, and 3 suggest that there is a possibility of using quality control.

The raw spectral data for the entire sample is shown in Figure 4a (resolution 5 nm). 4b is a spectrum obtained by transforming the raw spectrum using water treatment, and the function used is Savitzky. Golay is the first derivative and Smoothing is 9. The differential function is applied to increase the separation at each wavelength, matching the baseline of each spectrum. The regression equation (calibration equation) for calcium ion is shown in 4c and the regression equation for magnesium ion (Mg2 +) is shown in 4d (Table 14; the number of used PC is 4 and PC is the number of main component). The regression equation for sulfate ion is shown in Figure 4e (Table 15; number of PC used is 4), and regression equation for chloride ion is shown in 4f.

Claims (10)

(a) obtaining a reflection spectrum by irradiating near-infrared rays having a wavelength of 950 to 1650 nm to a salt having a known sulfate ion, magnesium, and moisture content;
(b) calculating a spectrum of the near infrared region obtained by the step (a) by multiplying scatter spectra of the differential spectra by multipath scattering; and (ii) measuring the sulfate ion, magnesium, obtaining a mathematical standard calibration equation from the correlation of the spectral variations at nm;
(c) irradiating the measured salt with near infrared rays having a wavelength of 950 to 1650 nm to obtain a reflection spectrum; And
(d) dividing the reflection spectrum of the near-infrared region obtained from the step (c) to correct multi-scattering of the differentiated differential spectrum, and then substituting the spectral values at 1150 nm and 1350 nm into the mathematical standard calibration equation, Simultaneously measuring the sulfate ion, magnesium, and moisture content contained in the measurement salt,
Wherein the derivative comprises a first derivative, a second derivative, or both, wherein the segment of the first derivative or second derivative is 5 units or 7 units, the smooth is 3, 7 or 9,
The method of simultaneously measuring sulfuric acid ion, magnesium and moisture content of salt using near infrared rays, characterized in that the sulfate ion, magnesium, and salt for which the moisture content is known and the salt for measurement are untreated. delete delete delete delete delete delete (a) obtaining a reflection spectrum by irradiating near-infrared rays having a wavelength of 950 to 1650 nm with a sulfate salt having known sulfate ion, magnesium, and moisture content;
(b) calculating a spectrum of the near infrared region obtained by the above step and multiplying the differential spectral spectrum by the multiple scattering correction, and (ii) measuring the sulfate ion, magnesium, obtaining a mathematical standard calibration equation from the correlation of the spectral variations at nm;
(c) irradiating near infrared rays having a wavelength of 950 to 1650 nm to the measured solar salt to obtain a reflection spectrum;
(d) dividing the reflection spectrum of the near-infrared region obtained from the step (c) to correct multi-scattering of the differentiated differential spectrum, and then substituting the spectral values at 1150 nm and 1350 nm into the mathematical standard calibration equation, Simultaneously measuring the sulfate ion, magnesium, and moisture content contained in the measuring sun salt; And
(e) determining the quality grade of the sun salt by the simultaneously measured sulfate ion, magnesium, and moisture content,
The water content is more than 5 wt% and not more than 10 wt%, and the content of sulfate ion is 0.1 And if the content of water is more than 10 wt% and not more than 15 wt%, and if the content of sulfate ions is more than 0.2 wt% and not more than 0.5 wt%, it is grade 3 , If it is out of the range of 1 to 3, it is judged to be out of grade;
Even if the content of the water and the content of the sulfate ion are included in the first grade, it is judged that the content of magnesium is in the range of 100-5,000 mg / L and the content of calcium exceeds the upper limit in the range of 500-1,000 mg / L. Even if the content of water and the content of sulfate ion are included in the second grade, it is judged that the content of magnesium is in the range of 5,000-8,000 mg / L and the content of calcium exceeds the upper limit in the range of 1,000-2,000 mg / L, Even if the content of water and the content of sulfate ion are included in the third grade, it is judged that the content of magnesium is outside the range of 8,000-10,000 mg / L and the content of calcium exceeds the upper limit of the range of 2,000-3,000 mg / L;
Wherein the derivative comprises a first derivative, a second derivative, or both, wherein the segment of the first derivative or second derivative is 5 units or 7 units, the smooth is 3, 7 or 9,
The method for measuring the quality of a salt of the present invention is characterized in that the sulfate ion, magnesium sulfate, delete delete

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