RU2243723C1 - Method for detecting nutritive value of animal meat - Google Patents

Abstract

FIELD: veterinary medicine, animal biochemistry.

SUBSTANCE: one should apply and extract out of animal muscular tissue as biological substrate which should be boiled in 5%-trichloroacetic acid solution, moreover, after the first cooling and before the second cooling one should supplement the sample under testing with 1 ml water-saturated diethyl ether at 1:1 ratio, moreover, cooling lasts for 15 min at centrifuging at 3 thousand rot./min for 15 min, then tubes should be supplemented with 2 ml 1%-condensate as resorcinol to perform photometry at wave length being 315 nm. This enables to widen biological possibilities.

EFFECT: higher accuracy of detection.

1 ex, 1 tbl

Description

The invention relates to the field of veterinary medicine, in particular animal biochemistry.

Determination of glycogen content is one of the important tests in identifying the energy resource of the animal organism.

Glycogen - a polysaccharide, or animal starch, is synthesized by the body and is deposited in all its organs and tissues. Glycogen is an easily mobilizable reserve form of glucose and is a branched polymer of blood glucose residues.

The determination of glycogen in the blood is known cytochemically by the ShIK reaction, by the Shabadash method [see Clinical Laboratory Analytics, ed. VV Menshikova Volume 2 - Private analytical technologies in a clinical laboratory. M .: “Labinform” - RAMLD, 1999. S. 59-61], where blood smears are prepared, fixed in absolute alcohol and incubated in a periodite solution and stained with Schiff's reagent, followed by staining with hemotoxylin and drying. Where glycogen stains in a cherry-violet color on a green background of the drug and microscopy.

The definition of blood glycogen is also known [Horeysi J. Et al. Zaklady chemickeho vysetrovani v lekarstvi. Pppraha, 1957. Reference Biochemical methods of research in the clinic. Edited by Academician of the Academy of Medical Sciences of the USSR prof. A.A. Pokrovsky Ed. “Medicine” M. - 1969. Determination of glycogen in the blood by the colorimetric method with orcine (according to Khoreishi), pp. 230-231], where glycogen is precipitated with alcohol, hydrolyzed in an acidic medium to glucose and heated in sulfuric acid, which turns into hydroxymethyl furfural and condenses with orcin, forming a colored compound. All of the above was carried out by boiling the test biological substrate in a concentrated sodium hydroxide solution in a centrifuge tube, followed by the addition of alcohol, cooling, centrifuging, selecting a supernatant, dissolving the precipitate in a semi-saturated sodium sulfate solution, followed by additional cooling, centrifuging and dissolving the sediment, while simultaneously adding test tube with test biological substrate in a control test tube with water and in p obirku with standard glucose solution 13 ml of sulfuric acid and 1 ml of 1% ortsina solution followed by heating, cooling, monitoring and photometry against determination of glycogen by the formula:

where X is the amount of glycogen, in mg%; E _about - the extinction of an experimental sample; E _article - extinction of a standard solution.

A disadvantage of the known methods is the inability to determine the glycogen content in the muscle tissues of animals to determine the nutritional value of animal meat.

The technical solution to the problem is the expansion of technological capabilities.

This object is achieved in that in a method for determining the nutritional value of animal meat, including boiling the test biological substrate in a centrifuge tube followed by the addition of alcohol, cooling, centrifuging, selecting a supernatant, dissolving the precipitate, followed by additional cooling, centrifuging and dissolving the sediment, simultaneously adding centrifuge tube with the test biological substrate, into a control tube with water and into a test tube with a standard astvorom glucose 13 ml of sulfuric acid and 1 ml of 1% condensate solution followed by heating, cooling, monitoring and photometry against determination of glycogen by the formula:

where G is the amount of glycogen, in mg%; E _about - the extinction of an experimental sample; E _st is the extinction of a standard solution, which is an extract from the muscle tissue of an animal that is boiled in a 5% trichloroacetic acid solution as a biological substrate, and after the first cooling and before the second cooling, 1 ml of diethyl ether saturated with water is added to the test sample 1 : 1, and cooling is carried out for 15 minutes, centrifuged at 3 thousand rpm for 15 minutes, add 2 ml of 1% condensate, which resorcinol is used in the test tubes, and photometer at a wavelength of λ = 315 nm.

The novelty of the proposed method is due to the fact that the proposed method allows to determine the glycogen content in the extract from the muscles, which determines the value of the meat. In addition, the proposed proposal is more economical, because does not require the use of particularly expensive chemicals.

An example of a specific implementation of the method for determining the nutritional value of animal meat

Animal muscle extract preparation

For this, an extract was prepared from the muscles of the femur and lower leg obtained from animals of cattle, pigs, sheep, rabbits, nutria, and frogs. The muscles were crushed with scissors and scrolled through a meat grinder, and then a homogenate was obtained. The homogenate was prepared using a manual homogenizer with a teflon pestle with the addition of physiological saline in a dilution of 1: 2 (1 part of the crushed muscles and 2 parts of physiological solution). Then the contents were transferred to conical flasks, left for 2 hours in the refrigerator, periodically mixing to obtain a saturated extract from the muscles, and filtered through a paper filter.

Solution preparation

To prepare 52% sulfuric acid with a volume of 325 ml, you need to take 225 ml of concentrated sulfuric acid and carefully pour 100 ml of distilled water.

To prepare a 1% resorcinol solution, you need to take 1 g of resorcinol and 99 ml of a 52% sulfuric acid solution.

To prepare a 5% solution of trichloroacetic acid, it is necessary to take 5 g of trichloroacetic acid and 99 ml of distilled water.

To prepare a standard glucose solution, take 10 mg of glucose and dissolve it with 300 ml of distilled water.

Precipitation and hydrolysis of glycogen from animal muscle extract

The resulting muscle extract was placed in a plastic centrifuge tube in an amount of 3 ml and 3 ml of a 5% trichloroacetic acid solution. Then the test tube was placed in a water bath for 1.5-2 hours, after cooling, 1 ml of diethyl ether saturated with water (1: 1) was added to the test tube, suspended and cooled on ice for 15 minutes, then the solution was centrifuged at 3 thous. / min for 15 minutes. The supernatant was carefully removed with a Pasteur pipette, and 1 ml of diethyl ether saturated with water (1: 1) was added to the precipitate and cooled on ice for 15 minutes, then centrifuged again at 3 thousand rpm for 15 minutes. After centrifugation, the supernatant was carefully removed with a Pasteur pipette, and the precipitate was mixed with 3 ml of distilled water, 13 ml of a 52% sulfuric acid solution was mixed, and 2 ml of 1% resorcinol.

In a control (clean tube) tube and with a standard glucose solution, 3 ml of distilled water was poured, 13 ml of a 52% sulfuric acid solution was mixed, and 2 ml of 1% resorcinol was mixed.

All tubes were placed in a water bath at 80 ° C for 20 minutes, then cooled on ice for 15 minutes. Test tubes with glucose had a brownish-yellow stain.

Photocallorimetry was performed against the control at KFK-3 when selecting a wavelength (λ = 315 nm). The calculation of glycogen content in the extract from the muscles is carried out according to the formula:

where G is the amount of glycogen, in mg%;

E _o - the extinction of the experimental sample;

E _article - extinction of a standard solution.

Example: in cattle

E _o - the extinction of the experimental sample was 0.845;

E _st - the extinction of the standard solution was 0.253.

гликогенаThus, substituting in the formula, we obtain the following result:

glycogen

Table 1 Glycogen content in animal muscle extract (M ± m; n = 10) Animal species The amount of glycogen, in mg% Cattle 333.9 ± 0.07 Pigs 301.9 ± 0.05 Sheeps 238.3 ± 0.02 Rabbits 2278.5 ± 0.09 Nutria 110 ± 0.08 Frogs 140.7 ± 0.03

According to table 1, we can conclude that rabbit meat has high nutritional value, then cattle meat, etc.

Claims (1)

A method for determining the nutritional value of animal meat, which involves boiling the test biological substrate in a centrifuge tube, followed by the addition of alcohol, cooling, centrifuging, selecting a supernatant, dissolving the precipitate, followed by additional cooling, centrifuging and dissolving the sediment, simultaneously adding the test biological substrate to the centrifuge tube, in a control test tube with water and in a test tube with a standard glucose solution of 13 ml of sulfuric acid and 1 ml of 1% condensate solution followed by heating, cooling, monitoring and photometry against definition of formula glycogen

where X is the amount of glycogen, mg%; E _about - the extinction of an experimental sample; E _article - extinction of a standard solution, characterized in that an extract from the muscle tissue of an animal is used as a biological substrate, which is boiled in a 5% trichloroacetic acid solution, and after the first cooling and before the second cooling, 1 ml of diethyl ether saturated with water 1: 1 is added to the test sample moreover, cooling is carried out for 15 minutes, centrifuged at 3000 rpm for 15 minutes, 2 ml of 1% condensate are added to the tubes, which are used resorcinol and photometer at a wavelength of λ = 315 nm.