Abstract:
Disclosed are an apparatus and a method for analyzing milk in a field, capable of analyzing the quality of milk by rapidly and easily examining components of milk in a field, other than a laboratory. To manage the quality of milk, a monochromator using an interference filter having different wavelength bands is employed to the apparatus for analyzing milk, and the amount of milk samples used at one time is increased, so components of milk are simultaneously examined. The apparatus for analyzing milk has a portable structure, so the components of milk are simply, rapidly and easily determined in the field, and the apparatus for analyzing milk is inexpensive as compared with existing apparatuses, thereby increasing the productivity.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims the benefit of Korean Patent Application No. 10-2008-0003729 filed on Jan. 14, 2008, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to an apparatus and a method for analyzing milk in a field. More particularly, the present invention relates to an apparatus and a method for analyzing milk for a field, capable of analyzing the quality of milk by rapidly and easily examining components of milk in a field, other than a laboratory. 
     2. Description of the Related Art 
     In general, in order to manage the quality of milk, components related to the milk quality are examined by using various measurement devices, and measured data obtained through the examination serves as a reference value to determine the quality of milk. 
     A conventional apparatus for analyzing milk is used for examining the components such as milk protein, milk sugar, etc., which are used to determine the quality of milk. The conventional apparatus has a wavelength band of about 400 to 2500 nm and includes a grating for scanning the wavelength of 400 to 2500 nm, so that the measurement time is substantially increased and the operational method is complicated. 
     In addition, the conventional apparatus for analyzing milk is manufactured suitably for the laboratory, so that the conventional apparatus for analyzing milk is mainly used for the laboratory. However, the conventional apparatus for analyzing milk is very sensitive, so it cannot be used in the field. In addition, since a sample cell has a size of 1 mm, an introduction of the sample cell is very difficult in the conventional apparatus for analyzing milk. 
     Further, since the amount of introduced sample cells is very small, the measurement must be performed several times in order to examine various components of milk. 
     In addition, the equipment for determining the quality of milk is very expensive laboratory equipment, so a laboratory must be provided to install the equipment. As described above, the conventional apparatus for analyzing milk has various disadvantages when it is used in the field. 
     SUMMARY OF THE INVENTION 
     Accordingly, it is an aspect of the present invention to provide an apparatus and a method for analyzing milk in a field, in which the operation of the apparatus is simple and easy, and the measurement is performed with high precision, so that components of milk is directly examined in the field, thereby rapidly determining the quality of milk. In addition, the amount of samples introduced at one time is increased, so that various components can be simultaneously examined, thereby minimizing the measurement time. 
     Additional aspects and/or advantages of the invention will be set forth in part in the description which follows and, in part, will be apparent from the description, or may be learned by practice of the invention. 
     The foregoing and and/or other aspects of the present invention are achieved by providing an apparatus for analyzing milk by examining specific components of milk. The apparatus includes a body connected to a power supply unit installed at an outside of the body, provided at an outer surface thereof with a monitor for outputting measured data, a power button for turning on/off power and an operating button for run, and formed at an upper end thereof with a cell introduction hole through which a sample cell is inserted, a lamp power, which is installed in the body and operates when the operating button is switched on, a plurality of lamp fixing brackets, which are installed in the body and equipped with halogen lamps connected to the lamp power to generate beam, a sample fixing part, which is disposed corresponding to the cell introduction hole and is mounted in the lamp fixing bracket to mount the sample cell thereon, a monochromator, which is mounted at a side of the sample fixing part and includes a filter slit type tube having slits formed at both sides thereof to allow a predetermined amount of beam to pass therethrough, a rotary plate, which is provided with a plurality of interference filters and is installed in the filter slit type tube, and a drive motor connected to the rotary plate, a detector, which is mounted at a rear surface of the filter slit tube to detect incident monochromatic light, and a processing unit, which is connected to the detector to transfer an electric signal output from the detector to the monitor as data. 
     It is another aspect of the present invention to provide a method for analyzing milk by examining specific components of milk, the method includes filling a milk sample in a sample cell to fix the milk sample to a sample fixing part and then irradiating beam of a halogen lamp to the milk sample through a lamp power, monochromating the beam of the halogen lamp, which has passed through the milk sample, by allowing the beam to pass through a plurality of interference filters of the rotary plate, transferring the monochromated beam to a detector and processing a signal of the monochromated beam output from the detector in a processing unit, and outputting data, which is output from the processing unit, through a monitor. 
     As described above, according to the apparatus and the method for analyzing milk in the field of the present invention, the monochromator using an interference filter having different wavelength bands is employed, and the amount of milk samples used at one time is increased, so milk protein, milk sugar, somatic cells butterfat, MUN (milk urea nitrogen), total solids, antibiotics, melamine, etc. can be simultaneously examined. 
     In addition, the apparatus for analyzing milk according to the present invention has a portable structure, so the components of milk can be simply, rapidly and easily determined in the field, instantly. In addition, the apparatus for analyzing milk according to the present invention is inexpensive as compared with existing apparatuses, thereby increasing the productivity. 
     Therefore, the apparatus and the method for analyzing milk according to the present invention can provide more fresh milk as compared with the conventional apparatus and the method for analyzing milk, so customers are satisfied, thereby promoting milk consumption. Further, if the apparatus and the method for analyzing milk according to the present invention are applied to milking cow farming, functional milk can be produced at a low price. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       These and/or other aspects and advantages of the invention will become apparent and more readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which: 
         FIG. 1  is a block diagram representing a configuration of an apparatus for analyzing milk in the field according to an embodiment of the present invention; 
         FIG. 2  is a perspective view representing an external appearance of the apparatus for analyzing milk in the field according to the embodiment of the present invention; 
         FIG. 3  is a perspective view representing an interior of a body of the apparatus for analyzing milk in the field including a filter-type monochromator according to the embodiment of the present invention; 
         FIG. 4  is an enlarged perspective view representing a sample fixing part according to the embodiment of the present invention; 
         FIG. 5  is an exploded and enlarged perspective view representing a monochromator according to the embodiment of the present invention; 
         FIG. 6  is a graph representing a result obtained by examining milk protein of milk according to the embodiment of the present invention; 
         FIG. 7  a graph representing a result obtained by examining milk sugar of milk according to the embodiment of the present invention; 
         FIG. 8  a graph representing a result obtained by examining somatic cell of milk according to the embodiment of the present invention 
         FIG. 9  a graph representing a result obtained by examining butterfat of milk according to the embodiment of the present invention; 
         FIG. 10  a graph representing a result obtained by examining MUN of milk according to the embodiment of the present invention; 
         FIG. 11  a graph representing a result obtained by examining total solids of milk according to the embodiment of the present invention; 
         FIG. 12  a graph representing a result obtained by examining antibiotics of milk according to the embodiment of the present invention; and 
         FIG. 13  a graph representing a result obtained by examining melamine of milk according to the embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Reference will now be made in detail to the embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the like elements throughout. The embodiments are described below to explain the present invention by referring to the figures. 
       FIG. 1  is a block diagram representing a configuration of an apparatus for analyzing milk in the field according to an embodiment of the present invention,  FIG. 2  is a perspective view representing an external appearance of the apparatus for analyzing milk in the field according to the embodiment of the present invention,  FIG. 3  is a perspective view representing an interior of the apparatus for analyzing milk in the field according to the embodiment of the present invention,  FIG. 4  is an enlarged perspective view representing parts of the apparatus according to the embodiment of the present invention, and  FIG. 5  is an exploded view representing parts of the apparatus according to the embodiment of the present invention. 
     The apparatus for analyzing milk in the field according to the present invention uses a monochromator  220  to which interference filters  223  having different wavelength bands are applied to measure components of milk corresponding to specific wavelength bands of the interference filters  223 , thereby simultaneously measuring various components of milk. 
     The apparatus for analyzing milk in the field according to an embodiment of the present invention mainly includes a power supply unit  100  and a body  200 . The power supply unit  100  according to the embodiment is additionally provided outside the body  200  to minimize the influence of the power supply unit  100  exerted on the body  200 , thereby maximizing the electrical stability. 
     As shown in  FIG. 2 , a monitor  202  provided in the form of an LCD screen is mounted at an outer surface of the body  200  to output a final result. Adjustment buttons are divided into a power button  203  for turning on/off the apparatus, an operating button  204  for run and a printing button  205  used when a data result output on the monitor  202  is printed out. The adjustment buttons are installed at an outer surface of the body  200 . 
     As shown in  FIG. 3 , a halogen lamp  210 , the monochromator  220 , a detector  230 , an amplifier  240 , a processing unit  250 , etc. are provided inside the body  200 . 
       FIG. 4  is an enlarged perspective view partially representing the interior of the body of the apparatus for analyzing milk using a filter-type monochromator according to the present invention, in which six halogen lamps  210  are provided in the body  200  to obtain stable data and each halogen lamp  210  is mounted on a lamp fixing bracket  212  at a side of a sample fixing part  213 . 
     A test tube type sample cell  206  containing a milk sample is mounted on the sample fixing part  213 . As shown in  FIG. 4 , the sample fixing part  213  has a rectangular shape, so that four halogen lamps  210  are disposed in front of the interference filter  223  and the remaining two halogen lamps  210  are disposed at a position that is rotated at about 90 degrees relative to the interference filter  223 . That is, the sample fixing part  213  is mounted between the lamp fixing bracket  212  and the monochromator  220  such that the sample fixing part  213  is disposed at an inner side of the lamp fixing bracket  212 . 
     In addition, a cell introduction hole  201  is formed through at an upper part of an outer surface of the body  200  corresponding to the sample fixing part  213  such that the sample cell  206  is inserted into the cell introduction hole  201 . 
     According to the embodiment of the present invention, the sample cell  206  is prepared in a size of 20 mm in use, so that a relatively large quantity of milk samples can be introduced at one time. Accordingly, a plurality of halogen lamps  210  are provided such that the beam is irradiated onto the sample cell  206  in various directions. 
     Meanwhile, since a lamp power  211  for turning on the halogen lamp  210  is mounted in the body  200 , if the operating button  204  is switched on, the halogen lamp  210  is operated by the lamp power  211 . 
     The monochromator  220  includes a filter slit type tube  221  a and  221  b having filter slits formed at a front surface and a rear surface thereof, respectively, a rotary plate  222  provided in the tube, and a drive motor  224  for rotating the rotary plate  222 . Six interference filters  223  are arranged on the rotary plate  222  in a circumference direction of the rotary plate  222  to filter beam having various wavelength bands. 
     The interference filters  223  are set to filter beams having wavelengths of 830 nm, 850 nm, 880 nm, 930 nm, 1200 nm (long pass filter) and 1100 nm (short pass filter) having a close relation with milk protein, milk sugar, somatic cells, butterfat, MUN (milk urea nitrogen), total solids, antibiotics, melamine, etc., which are necessary for analyzing the milk such that the total components of milk can be measured. 
     In other words, each interference filter  223  is applied to each component necessary for analyzing the milk, and weight is set with respect to the six representative wavelengths, so the weight is defined as a constant corresponding to each component. 
     Meanwhile, the detector  230  is installed at a rear surface of the filter slit type tube  221   b  such that a beam monochromated through the interference filter  223  passes through the detector  230  and converted into an electric signal. 
     The electric signal is uniformly amplified by the amplifier  240  connected to the detector  230 , and data is output on the monitor  202  provided at the outer surface of the body  200  through the processing unit  250  connected to the amplifier  240 . 
     As described above, according to the present invention, many components of milk can be simultaneously measured and analyzed through a simple operation, which is performed by filling the sample cell  206  with the milk sample and fixing the sample cell  206  to the sample fixing part  213 , and then pushing the power button  203  and the operating button  204 . In addition, since the apparatus for analyzing milk can be used in practice, the quality of milk can be simply and rapidly analyzed in various fields dealing with milk, such as a milking cow farm house, a manufacturer of dairy product, a mart, etc. 
     Hereinafter, an operation of the apparatus for analyzing milk according to the embodiment of the present invention will be described. 
     A standard value is set by measuring components of water serving as a reference cell before the components of milk are measured. 
     Milk to be subject to the quality analysis is selected and then filled in the sample cell  206 . Then, the sample cell  206  is input through the cell introduction hole  201  of the body  200  and fixed to the sample fixing part  213 . 
     Then, power is supplied to the body  200  through the power supply unit  100 , and the power button  203  of the body  200  is pressed for switch-on and then the operating button  204  is pressed. 
     Accordingly, the lamp power  211  is turned on to supply power to the halogen lamp  210 , so that the halogen lamp  210  generates a beam. 
     As the beam passes through the milk sample contained in the sample cell  206 , a predetermined amount of beam is introduced through the slit of the filter slit type tube  220   a , so that dispersed light is minimized and the influence of the dispersed light is minimized. The beam, which has passed through the front slit, is monochromated while passing through the interference filter  223  of the rotary plate  222 . 
     At this time, the rotary plate  222  makes one rotation by the drive motor  224  and the interference filter  223  monochromates the beam according to wavelength bands, so that specific components of the milk sample are represented as a spectrum. 
     While the rotation plate  222  is making one rotation, the six interference filters  223  can measure all components of the milk. Therefore, the operating button  204  is pushed such that the rotary plate  222  makes one rotation. 
     That is, as the rotary plate  222  makes one rotation, the beam, which has passed through the filter slit type tube  221 , is monochromated by the six interference filters  223 , thereby producing the spectrums of the milk components corresponding to the wavelength bands. 
     As described above, the beam monochromated by the interference filter  223  passes through the filter slit type tub  221  b formed at the rear surface of the filter bracket  220  and then is introduced into the detector  230 . The detector  230  detects the specific components of milk using the monochromated beam introduced into the detector  230 . 
     In this case, since dispersed light is minimized by the filter slit type tubes  221   a  and  221   b , the monochromated light introduced into the detector  230  produces the spectrum corresponding to the wavelength bands of the interference filters  223 . 
     Then, the detector  230  converts the detected specific components into the electric signal and transfers the electric signal to the amplifier  240 . The amplifier  240  uniformly amplifies the received electric signal and transfers the amplified signal to the processing unit  250 . 
     After that, the processing unit  250  collects and processes the amplified signal to output data through the monitor  202 . 
     If necessary, the printing button  205  is pushed to print the output data. 
     The correlation between the measured values of the components of milk, which are measured through monochromation performed by the interference filter  223 , and the standard value corresponding to a measured value of water serving as the reference cell is represented by a calibration curve using regression analysis (a linear correlation equation using regression analysis). 
     A coefficient R 2 , which corresponds to a coefficient of correlation of the calibration curve and serves as a measure of a linearity, is used as a measure of desirability of the correlation between the measured value of milk and the standard value of water. A standard deviation of the data is represented by using SEC (Standard error of calibration) and SEP (Standard error of prediction). 
     When the measured value of milk and the standard value of water is represented in the form of a straight line, if data of the measured value of milk and the standard value of water roughly form a predetermined straight line in consideration of R 2 , SEC and SEP, the correlation between the measured value of milk and the standard value of water is determined to be desirable. 
     That is, if R 2  is nearly 1, and SEC and SEP are nearly 0, the correlation between the measured value of milk and the standard value of water is determined as desirable. 
     The correlation between the measured value of water and the standard value is represented by using an MLR (Multiple Linear Regression) of the calibration curve. 
     In addition, a routine analysis is performed using the calibration curve formed through the measured value of milk, and reliability of significance of the routine analysis value is represented by an RMSEP (Root Mean of Standard Error Prediction). 
     As the reliability significance is checked, the reliability of the value of milk components measured by the signal passing through the interference filters  223  and the values of components actually contained in milk is estimated. 
       FIG. 6  is a graph representing a result obtained by examining milk protein of milk according to the embodiment of the present invention. Since R 2  is 0.93 and the calibration curve has a nearly linear configuration, the measured value of the milk protein is reliable. Therefore, a numerical value of the milk protein of milk can be estimated through the measured value of the milk protein. 
       FIG. 7  is a graph representing a result obtained by examining milk sugar of milk according to the embodiment of the present invention. Since R 2  is 0.94 and the calibration curve has a nearly linear configuration, the measured value of the milk sugar is reliable. Therefore, a numerical value of the milk sugar of milk can be estimated through the measured value of the milk sugar. 
       FIG. 8  is a graph representing a result obtained by examining somatic cell of milk according to the embodiment of the present invention. Since R 2  is 0.94 and the calibration curve has a nearly linear configuration, the measured value of the somatic cell is reliable. Therefore, a numerical value of the somatic cell of milk can be estimated through the measured value of the somatic cell. 
       FIG. 9  is a graph representing a result obtained by examining butterfat of milk according to the embodiment of the present invention. Since R 2  is 0.94 and the calibration curve has a nearly linear configuration, the measured value of the butterfat is reliable. Therefore, a numerical value of the butterfat of milk can be estimated through the measured value of the butter fat. 
       FIG. 10  is a graph representing a result obtained by examining MUN of milk according to the embodiment of the present invention. Since R 2  is 0.91 and the calibration curve has a nearly linear configuration, the measured value of the MUN is reliable. Therefore, a numerical value of the MUN of milk can be estimated through the measured value of the MUN. 
       FIG. 11  is a graph representing a result obtained by examining total solids according to the embodiment of the present invention. Since R 2  is 0.94 and the calibration curve has a nearly linear configuration, the measured value of the total solids is reliable. Therefore, a numerical value of the total solids of milk can be estimated through the measured value of the total solids. 
       FIG. 12  is a graph representing a result obtained by examining antibiotics of milk according to the embodiment of the present invention. The R 2  of four representative antibiotics including PPS injection (penicillin G, beta-lactam based, A), tylocetin (chloramphenicol, B), terramycin (tetracycline, C), sulfa-40 (sulfadimethoxine sodium, D) is 1, and the calibration curve is almost linear, the measured value of the antibiotics is reliable. Therefore, a numerical value of the antibiotics of milk can be estimated through the measured value of the antibiotics. 
       FIG. 13  is a graph representing a result obtained by examining melamine of milk according to the embodiment of the present invention. Since R 2  is 0.99 and the calibration curve has a nearly linear configuration, the measured value of the melamine is reliable. Therefore, a numerical value of the melamine of milk can be estimated through the measured value of the melamine. 
     Although few embodiments of the present invention have been shown and described, it would be appreciated by those skilled in the art that changes may be made in these embodiments without departing from the principles and sprit of the invention, the scope of which is defined in the claims and their equivalents.