SU964528A1 - Device for determining fat and protein content in milk and milk products - Google Patents

Description

The invention relates to dairy thrombus content / in particular to devices for simultaneously determining the fat content h of protein in milk and dairy products that can be used in agriculture, in dairy enterprises and in research laboratories x.

A device for determining the content of fat and protein in milk and dairy products is known. Parallel cavity, diaphragm, light filter, power supply and measurement units 1.

However, the known device allows C-high accuracy to determine the content of components in different samples only in the case when the temperature of the light source and the photodetectors remains constant. Failure to comply with these conditions leads to a significant increase in measurement error. A similar picture is observed

with and with aging elements. It requires the use of automatic temperature control of the device or

the introduction of additional corrections, which presents a certain complexity.

The aim of the invention is to improve the accuracy of determining the content of g and protein in milk.

The goal is achieved. the fact that the device for determining the content of fat and protein in milk and dairy products, containing a light source installed on the opposite side of the photodetectors of the direct and diffuse light streams in the focus of the cuvette, made in the form of a two convex lens

 with a centrally located flat parallel CAVITY, diaphragm, light filter, power supply units and measurements. Rheni is equipped with a source of reference voltage, voltage regulator and corrective photodetector,

25 mounted on the diaphragm from the side of the light source, while the source of the reference, for example: xeni and the correction photo detector, is connected to an adjustable amplifier via a differential amplifier.

Claims (1)

30 torus of the light source. The drawing shows the block-scheg.1a device. The device contains a source of reference voltage 1 and a corrective photodetector 2 mounted on diaphragm 3 from the side of source 4 of the light. The source 1 of the reference voltage and the corrective photodetector 2 are connected to the inputs of the differential amplifier 5, and its output is connected to the voltage regulator b, the output of which is connected to the light source 4 located in the focus of the convex cuvette 7 with a controlled milk sample. Luminous flux falls on. corrective photodetector-2, the amount of transmitted light is controlled by the diaphragm 3. The required wavelength of the light flux is separated by a light filter 8. The optical cell of the optical cell 9 concentrates the direct transmitted light to the direct received optical light 9, located on the converging light collecting lens 10. from the source 4 of the light at the focus of the convex cup 7. The photodetector 9 serves to convert the transmitted light into an electrical signal and to prevent This collision of the luminous flux in the lens 10. Photocell 11rasse nnogo luminous flux is set for the converging lens 10 in Fokal plane of a lens perpendicular to the optical axis of the light source 4. The signals of the photodetectors 9 and 11 enter the measurement unit 12, the measurement result is output by the display unit 13. Power is supplied from power supply unit 14. The device works as follows. The investigated milk sample is placed in a cuvette 7. The rays of the source 4 light. arrive at a corrective photodetector 2, where they are converted into an electrical signal, the value of which is compared with the value of the reference voltage in the differential amplifier 5. The unbalance signal from the output of the differential amplifier 5 delivers a correction signal to the voltage regulator 6. As a result, the voltage at the light source 4 changes to a value when the signal unbalance becomes zero. The light rays passing through the diaphragm 3 and the light filter 8 emitting a certain wavelength of the spectrum fall on the optical cell 7 with the breakdown of milk, where it is partially scattered in proportion to the amount of fat and protein in the milk. The transmitted light and the scattered light fluxes by the photoreceivers 9 and 11 are converted into electrical signals and enter the measuring unit 12. The use of modern elemental base allows us to achieve the stabilization factor of the output signal of the photodetectors in a wide temperature range of more than 5000, while the corrective photodetector 2 should be similar to the photoreceivers 9 and 11. This allows determining the content of fat and protein with high accuracy without additional corrections or application automatic thermoregulators. Claim I Device for determining the content of fat and protein in milk and dairy products, containing a light source mounted on the opposite side of the photodetectors of the transmitted and scattered light fluxes in the focus of the cuvette made in the form of a two-convex lens with a centrally located plane-parallel cavity , diaphragm, light filter, power supply and measurement units, which are based on the fact that, in order to improve accuracy, it is equipped with a reference voltage source, voltage regulator and correction A photodetector mounted on the diaphragm on the side of the light source, the source of the reference voltage and the corrective photodetector being connected via a differential amplifier to the light source voltage regulator. Sources of information accepted. In consideration during the examination 1. USSR author's certificate in application No. 2915578 / 28-13, cl. G 01 N 33/06, 1980.