RU2681501C1 - Method for evaluating the quality of pig meat - Google Patents

Abstract

FIELD: agriculture.

SUBSTANCE: invention relates to the field of agriculture, namely to assess the quality of meat of pigs. Method consists in measuring for 1 min the electrical resistance of muscle tissue by introducing into the region of the longest back muscle for 1 h after slaughter of an animal to the depth of 10 mm the sensor of an alternating current typical bridge E7-4, which represents the device of two electrodes with the diameter of 1.5 mm, fixed at the distance of 10 mm from each other in a dielectric board, and the division of meat into NOR quality groups at R=86–385 Ohm, with the PSE meat defect at R≤85 Ohm and DFD at R≥386 Ohm.

EFFECT: easy and fast sorting of meat into groups of quality after slaughter of animals is provided.

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Description

The invention relates to the field of agriculture, pig farming.

In pig breeding, by far the most common indicators used in determining the quality of pork are its color, pH, water retention, stiffness and marbling.

A known method for determining pH using a multifunctional portable analyzer (Itzygin OB Development of an express analyzer of food quality. - Collection of abstracts of the exhibition-seminar "Advanced Russian Technologies", Seoul, 12-15.05.1998). The developed multifunctional sensor for 30 s produces a multichannel measurement of pH, temperature and concentration of C1 ion. Processing of the measured electrical signals and their digital indication on the liquid crystal display are carried out using a specially designed microprocessor-based measuring transducer built into the sensor housing. This method of meat control is based on exposure to electromagnetic radiation of a certain range of wavelengths and measuring the intensity of their reflection. At the same time, as the indicator correlating with meat quality, the ratio of the measured values of the reflection intensity values of the test sample and the standard using a color ball comparator is used, and meat quality control is carried out taking into account the obtained values of this ratio. The method allows for the rapid analysis of meat quality by color and sorting of carcasses into qualitative groups after slaughter of animals (Patent RU No. 2092836, 10.10.97).

However, the implementation of the method requires a knowingly benign reference sample, the color of which is close to the test and which must be changed when changing the batch of meat, which limits the possibilities of using the method.

There is a method of assessing the quality of beef during life by determining the difference in the electric skin resistance of a slaughtered animal in the BAT Teng Fu on the positive and negative potentials of the PERT-4M electro-puncture device. NOR meat is characteristic when the potential difference in BAT Teng Fu is less than 5 μA, DFD is more than 5 μA (Consumer properties of meat with deviations in the process of autolysis / V.I. Krishtafovich, S.V. Kolobov, D.I. Yablokov // Meat industry. - 2005. - No. 1. - S. 30-33).

The disadvantage of this method is the ability to determine only stress resistance or stress sensitivity of the animal, without dividing the beef into DFD, PSE and NOR.

There is a method of determining the quality of meat, involving sample preparation and measurement of the reflection coefficient of a meat sample at wavelengths of 480-520 and 640-720 nm and quality assessment by calculating the ratio of measured values (Protein preparations and food additives in the meat industry / G.V. Gurinovich, NN Potipaeva, VM Pozdnyakovsky. - M. Kemerovo: Publishing Association "Russian Universities": "Kuzbassvuzizdat: ASTSH. - 2005. - 362 p.).

The disadvantage of this method is the duration and complexity of the process, due to the sequential measurement of the reflection coefficient of individual meat samples, the calculation of the intensity of its color according to the formula and the subsequent quality assessment. With this method, it is not possible to sort the meat on PSE, DFD and NOR.

A known method of sorting meat into quality groups PSE, DFD and NOR (Patent RU 2477471, 03/10/2013). After separation of animals into stress-resistant and stress-sensitive potential differences in BAT Teng Fu (between 5-6 spinous processes of the thoracic section) in live animals, it is necessary after 45 minutes. after slaughter, by measuring the pH in the longest muscle of the back, among the stress-sensitive animals, isolate meat with PSE properties (pH below 5.7) and DFD (pH above 6.2).

The disadvantage of this method is the complexity and duration of execution.

The analysis of modern instrumental methods for the express analysis of raw material quality indicators shows that the main criteria for choosing control methods are the following indicators: analysis duration (no more than 3 minutes), relative determination error (no more than 5%), labor input and suitability for automation of production result.

Based on the theoretical and experimental studies, as the most acceptable method, we propose a method for assessing the quality of pig meat by measuring the electrical resistance of muscle tissue.

The technical result of the invention is the possibility of simple and quick sorting of meat into quality groups after slaughter of animals.

The specified technical result is achieved due to the fact that, as a criterion for assessing the quality of meat, electrical resistance of muscle tissue in the region of the longest back muscle is used, on the basis of which, after slaughter, animals are divided into stress-resistant, giving meat NOR at R = 86-385 Ohm, stress-sensitive with meat defect PSE at R≤85 Ohm and DFD at R≥386 Ohm.

The process of deterioration of meat quality is due to biochemical processes in which there is an increase in membrane permeability, and, consequently, a weakening of the effect of electrical polarization at the interface between conductive media. The capacitive properties of biological tissue are quite sensitive to external influences. For example, the structure of the membranes changes with changes in the diet of the animal, with diseases, stresses and other changes in the environment of the cell membrane.

The implementation of the invention.

Quality separation of meat into PSE, DFD and NOR is carried out by measuring the electrical resistance of muscle tissue after slaughter.

Measurement of the electrical resistance of muscle tissue is carried out within 1 hour after slaughter using a typical AC bridge E7-4 at a frequency of 1 kHz. The sensor is a device of two electrodes with a diameter of 1.5 mm, mounted at a distance of 10 mm from each other in a dielectric board. A sensor is inserted into the region of the longest muscle of the back to a depth of 10 mm and for 1 min. take into account the resistance of muscle tissue.

Then, the quality of meat is divided into NOR at R = 86-385 Ohms, with a meat defect PSE at R≤85 Ohms and DFD at R≥386 Ohms.

The method is industrially applicable.

Example 1. For the experiment, 40 pigs were slaughtered with a live weight of 105-110 kg at the age of 7 months. The study was carried out within 1 hour after the slaughter using a standard AC bridge E7-4. A sensor was introduced into the region of the longest muscle of the back, which is a device of two electrodes with a diameter of 1.5 mm fixed at a distance of 10 mm from each other in a dielectric board, to a depth of 10 mm and for 1 min. muscle tissue resistance was taken into account. The temperature of the samples ranged from 20 to 25 ° C.

Electrophysical biological tissues of animal origin can be considered as a complex dielectric consisting of two or more layers of different conductivity. The value of electrical resistance of muscle tissue depends on the orientation of the electrode density relative to the direction of muscle fibers and the presence of fatty inclusions. The resistance of adipose tissue is an order of magnitude greater than that of muscle. Therefore, from 10 to 12 measurements in different planes were performed on each sample and the average value was calculated.

The quality of the meat was further evaluated in the laboratory. The number of carcasses meeting the requirements of NOR n = 25, PSE n = 7, DFD n = 8 was revealed.

The research results are presented in table 1.

The value of the electrical resistance of the longest muscle of the back, measured on the carcasses of pigs by the proposed method, allows to reliably judge the quality of meat:

- at R = 86-385 Ohm - NOR;

- at R≤85 Ohm - PSE;

- at R≥386 Ohm - DFD.

Claims (1)

A method for assessing the quality of pig meat, which consists in measuring for 1 min the electrical resistance of muscle tissue by introducing into the region of the longest back muscle for 1 hour after slaughtering the animal to a depth of 10 mm of a sensor of a typical E7-4 AC bridge, which is a device of two electrodes with a diameter of 1.5 mm, fixed at a distance of 10 mm from each other in a dielectric board, and dividing the meat into quality groups NOR at R = 86-385 Ohms, with a meat defect PSE at R≤85 Ohm and DFD at R≥386 Ohm .