RU2504770C1 - Milk quality determination method - Google Patents

Abstract

FIELD: food industry.

SUBSTANCE: during the method implementation one simultaneously measures concentration of potassium ions in milk and quantity of somatic cells, compares measurement indices and, according to their result, concludes on milk quality: at potassium ions concentration values equal to 11.0-20.0 mg % which corresponds to somatic cells content value equal to less than 400 thous/cm³ - premium quality milk, at potassium ions concentration values equal to 6.0-11.0 g % which corresponds to somatic cells content value equal to 400 - 1000 thous/cm³ - 1^st grade milk, at values higher the said ones - milk off-grade in terms of quality.

EFFECT: determination accuracy and objectivity enhancement.

1 ex, 1 tbl, 1 dwg

Description

The invention relates to the dairy industry, in particular for determining the quality of milk.

A known method for determining the quality of milk and dairy products for contamination with mycotoxins. The method involves immunoaffinity concentration and enzyme-linked immunosorbent determination of aflatoxin M1 in the volume of a gel with grafted antibodies / 1 /.

A known method for the rapid assessment of the quality and biological value of milk, including carrying out iron-induced chemiluminescence with the addition of iron sulfate solution to milk, measuring the light sum of the product’s luminescence by chemiluminescent analysis for 5 minutes at an ambient temperature of 25 ° C, milk has a milk pH of 6.55- 6.75, determine the light sum and maximum luminosity of chemiluminescence at their values, respectively 3.5 cu and less than 0.85 cu The product is evaluated as preserving the quality and biological value / 2 /.

The disadvantage of the above methods for determining the quality of milk is their complexity and high cost.

A known method for determining the quality of milk, including determining the concentration of ammonium ions in the sample and judging by the received data on the quality of milk. The concentration of ammonium ions in milk is determined by clarification of the milk sample and its subsequent photometry. The method is based on the determination of ammonium ions in an alkaline medium by their reaction with phenol in the presence of an oxidizing agent with the formation of a kinetically stable highly colored compound. / 3 - prototype.

The disadvantage of this method is the complexity of its implementation and additional costs for reagents.

The main indicators characterizing the quality of milk are: fat content, protein content, SOMO (dry skim milk residue), somatic cell content (SSC), the presence of inhibitors, heat resistance, freezing point, etc.

The amount of CCK in 1 ml of milk has a significant impact on the safety, quality and yield of dairy products. When the content of somatic cells is not more than 400 thousand / cm ³ milk is evaluated as milk of the highest grade, when the content of somatic cells is not more than 1 000 thousand / cm3, milk is evaluated as milk of 1 and 2 varieties / 4 /.

The number of somatic cells is determined according to GOST 23453-09 “Methods for determining the number of somatic cells. The method is based on the interaction of the drug "Mastoprim" with somatic cells, as a result of which the consistency of milk / 5 / changes.

However, this significant indicator of milk quality in terms of the number of somatic cells is not sufficiently accurate and objective, because does not reflect changes in the chemical composition of milk (the content of chlorine ions, sodium, the amount of whey proteins, etc.) that occur in diseases of animals. In addition, during centrifugal purification of milk in the separator mucus, along with mechanical impurities, microorganisms and larger shaped elements of the blood, including somatic cells, settle.

The task of the invention is to improve the accuracy and objectivity of determining the quality of milk, in the final case, its grade.

Improving the accuracy and objectivity in determining the quality of milk is carried out due to the fact that the concentration of potassium ions in milk is measured and the obtained indicators are compared with the indicators of the number of somatic cells, and with values of the concentration of potassium ions (in mg%) from 11.0-20.0 corresponding the somatic cell content (in thousand / cm ³ ) is less than 400 - milk of the highest grade, with concentration values from 6.0-11.0 mg% corresponding to the somatic cell content from 400 to 1000 thousand / cm ³ - milk of the first grade, with values large above these - milk of the same quality varietal.

If the dependence of the quality (grade) of milk on the limits of indicators of the number of somatic cells is known, then in the future it will suffice to determine only the number of potassium ions in the milk when determining its quality (grade).

The concentration of potassium ions is determined by the potentiometric method using a potassium selective electrode. The potentiometric method is based on measuring the electromotive force (EMF) of the electrode system immersed in the test solution, consisting of a potassium selective electrode and a reference electrode. Sampling and preparation for testing was performed according to GOST 3622-88. Before examining the sample, the system was calibrated using standard potassium chloride solutions with a concentration of 10 to 1 mol / L. An initial solution of potassium chloride with a concentration of 1 mol / L was prepared by the gravimetric method. The remaining solutions were prepared by tenfold dilution. Based on the results obtained, a graph was constructed of the dependence of the electrode potential on the negative logarithm of the concentration of potassium ions in solution. The temperature of the test milk was brought to the temperature of the calibration solutions with an accuracy of ± 5 ° C.

After calibrating the electrode system in potassium chloride solutions, it was washed with distilled water. Immersed in the test milk (the recommended sample volume is 50-100 ml) and readings from the display of the device. Settling time - 2 minutes. The measured value was compared with a calibration graph, which determined the concentration of potassium ions in the test milk.

To assess the quality of milk, milk procured in 30 farms of the Leningrad Region in 2009-2012 was investigated. The Appendix presents a table of indications of correspondence of indicators of the number of somatic cells and the number of potassium ions in milk. According to these data, a graph is plotted on the drawing. Based on these data, we can conclude that by the concentration of potassium ions it is possible to judge the quality (grade) of milk. An example implementation of the method.

They took 100 g of whole milk, heated to 20 ° C, lowered the electrodes and took readings. At the same time, the number of somatic cells on a Somatos-M instrument was measured in this sample. As a result, 2 values were obtained: on the Somatos-M device and the concentration of potassium ions, which were used to judge the quality (grade) of milk. After repeated and one-year studies, it was concluded that to assess the quality (grade) of milk, it is sufficient to determine the concentration of potassium ions in the milk, and not the number of somatic cells.

Literature

1. Patent for invention No. 2361203, publ. 07/10/2009.

2. Patent for invention No. 2402764, publ. 10/27/2010

3. Patent for the invention No. 2193773, publ. January 17, 2001

4. The Federal Law “Technical Regulations for Milk and Dairy Products” (as amended by the Federal Law of July 22, 2010 N 163-ФЗ).

5. GOST 23453-90 “Milk. Methods for determining the number of somatic cells. "

application No. p / p Somatic cell count, thousands / cm ³ The amount of potassium ions, mg% No. p / p The number of somatic cells, thousand / cm ³ The amount of potassium ions, mg% one 265 19 51 436 11.6 2 272 eighteen 52 442 11.8 3 293 17,2 53 446 11,4 four 300 16,4 54 449 12 5 311 18.1 55 454 12.6 6 315 16 56 460 10.7 7 317 fifteen 57 461 12.47 8 323 16.8 58 468 11.8 9 324 16 59 469 10.9 10 328 eighteen 60 471 12.6 eleven 329 16 61 478 11.6 12 334 fifteen 62 479 12,4 13 335 15,2 63 481 11.3 fourteen 337 fifteen 64 485 12 fifteen 347 14.56 65 486 11.6 25 348 17 66 486 11,4 16 351 13 67 487 9.8 17 351 13.5 68 488 11.5 eighteen 351 13 69 489 12.1 twenty 353 fourteen 70 490 11.6 21 354 16,2 71 493 10.94 22 357 fifteen 72 494 10.8 23 363 13 73 495 11.71 24 363 14.8 74 496 10.5 26 369 12.8 75 497 11.3 27 371 16.5 76 498 10.1 28 374 14.9 77 500 10.7 29th 374 14.2 78 521 10,2 thirty 375 fourteen 79 536 10 31 378 12,4 80 540 9.27 32 379 13 81 563 9.97 33 383 12 82 588 9.3 19 388 12.3 83 612 8.71 34 391 fifteen 84 631 8.8 35 391 15,2 85 650 8.8 36 396 13,4 86 667 8.1 37 396 12.68 87 689 8 38 398 13.6 88 705 7.9 39 403 12 89 728 7.7 40 403 11.71 90 733 7.36 41 408 fifteen 91 768 7.2 42 410 fourteen 92 795 7 43 412 13.6 93 824 6.9 44 415 fourteen 94 837 6.8 45 416 11.8 95 868 6.5 46 423 fourteen 96 894 6.6 47 425 12.26 97 940 6.2 48 427 11,2 98 953 6.3 49 428 13 99 965 6.1 fifty 431 11,2 one hundred 1000 6

Claims (1)

A method for determining the quality of milk, including measuring the number of somatic cells in milk and judging by the received data on the quality of milk, characterized in that the concentration of potassium ions in the milk is simultaneously measured and the measurement parameters of somatic cells and the concentration of potassium ions are compared and the quality of milk is judged by the results , wherein at concentrations of potassium ions from 11,0-20,0 mg% corresponding to the value of somatic cell content of less than 400 thousand / cm ³ - the highest grade milk, with the concentration values uu mg of 6,0-11,0% of the respective value of the somatic cell content of from 400 thousand to 1000 / ^cm3 - 1 grade milk, with larger values above - the milk of the same quality cultivar.

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