Device for measuring oxidation stability of oil and fat

Abstract

The utility model relates to a kind of oil oxidation stability determination device, including bottom plate, heating container, measuring container, test tube, electrode, electric conductivity determination instrument, its technical key points are: heating container is composed of heat-conducting base, transparent wall cylinder, expanding diameter gland, the top surface side of expanding diameter gland is fixed with longitudinal push-pull cylinder, the outside of transparent wall cylinder is equipped with concentric ring frame, the top surface of concentric ring frame is connected and fixed with the lower end of longitudinal push-pull cylinder stem, annular lamp group towards transparent wall cylinder is fixed on the inner ring surface of concentric ring frame, longitudinal guide assembly is equipped between concentric ring frame and expanding diameter gland, the through-hole corresponding test tube is equipped on expanding diameter gland, positioning cap is equipped on test tube upper end, exhaust pipe mouth and first air inlet pipeline leading to test tube lower part are equipped on positioning cap, the cover plate of measuring container is fixed with the second air inlet pipeline that communicates with exhaust pipe mouth. The device considers the determination of temperature and illumination condition to the influence of oil oxidation stability, further satisfy determination demand.

Description

Technical Field

[0001] This utility model relates to the technical field of oil and fat detection devices, specifically to an oil and fat oxidation stability measuring device. Background Technology

[0002] Oils and fats are prone to oxidation during storage, leading to increased acid and peroxide values. This not only affects their taste and texture but also makes them difficult to metabolize and can even damage the liver. The oxidative stability of oils and fats reflects their storability, i.e., their ability to resist auto-oxidation. Testing the oxidative stability of oils and fats is essential for evaluating their quality and for researching oil storage technologies.

[0003] Conductivity meters are commonly used to determine the oxidative stability of oils and fats. They determine this stability by measuring changes in conductivity during oxidation. In operation, clean air is introduced into the oil sample to accelerate the oxidation of glycerol fatty acids, producing volatile organic acids. The air then carries these volatile organic acids into a conductivity chamber, where the measuring solution dissolves them, ionizing them and altering the solution's conductivity. The conductivity meter continuously measures the conductivity. A sharp increase in conductivity indicates the end of the induction period. By measuring the induction period, the conductivity meter obtains the oxidative stability index (OSI) of the oil, reflecting its storage stability.

[0004] For example, CN 205898729 U discloses a device for detecting the oxidative stability of oils and fats, which includes a conductivity meter, a vent pipe, and a heater. The heater contains a heating block, and multiple test tubes are positioned above the heating block. Each test tube contains a vent pipe and an outlet pipe. The other end of the vent pipe is connected to an air filter, with an air inlet at the left end of the air filter. The other end of the outlet pipe leads to a measuring container containing a measuring solution. Electrodes are placed within the measuring solution, and the other ends of the electrodes are connected to the conductivity meter. This detection device is designed with multiple sample heating reactors connected to the measuring electrodes, allowing for simultaneous testing of multiple samples and thus improving work efficiency. However, the following problem remains: external environmental light conditions also affect the oxidative stability of oils and fats. This device only reflects the effect of temperature on the oxidative stability of oils and fats, and needs further improvement. Utility Model Content

[0005] The purpose of this invention is to provide a reasonably structured and reliable device for measuring the oxidative stability of oils and fats, which solves the above problems and takes into account the influence of temperature and light conditions on the oxidative stability of oils and fats, thereby further meeting the measurement requirements.

[0006] The technical solution of this utility model is: An apparatus for determining the oxidative stability of oils includes a base plate, a heating container, a measuring container, a test tube disposed in the heating container, an electrode disposed in the measuring container, and a conductivity meter connected to the electrode. The key technical features are as follows: the heating container comprises a heat-conducting base, a transparent wall cylinder disposed on the upper part of the heat-conducting base, and an expanded-diameter cap disposed at the upper end of the transparent wall cylinder. A longitudinal push-pull cylinder is fixed to one side of the top surface of the expanded-diameter cap. A concentric ring frame is disposed on the outer side of the transparent wall cylinder. The top surface of the concentric ring frame is connected and fixed to the lower end of the cylinder rod of the longitudinal push-pull cylinder. An annular lamp assembly facing the transparent wall cylinder is fixed on the inner ring surface of the concentric ring frame. A longitudinal guide assembly is disposed between the concentric ring frame and the expanded-diameter cap. The expanded-diameter cap has a through hole corresponding to the test tube. A positioning cap is disposed at the upper end of the test tube. The positioning cap has an exhaust port and a first air inlet pipe leading to the lower part of the test tube. A second air inlet pipe communicating with the exhaust port is fixed on the cover plate of the measuring container.

[0007] In the aforementioned oil oxidation stability testing device, the expanded diameter pressure cap has a groove recessed into the upper opening of the heating container, the through hole is located on the bottom surface of the groove, the positioning cap is located in the groove, and the groove is provided with heat-insulating filler surrounding the positioning cap.

[0008] In the aforementioned apparatus for determining the oxidative stability of oils, a heater is embedded in the base plate and is in contact with the heat-conducting base.

[0009] The aforementioned apparatus for determining the oxidative stability of oils and fats includes a heating medium solution in the heating container, which enables water bath heating of the test tubes.

[0010] The aforementioned oil oxidation stability testing device comprises a longitudinal guide assembly consisting of a vertical rod fixed to the edge of the lower surface of the expanded diameter cap and a guide sleeve located at the edge of the top surface of the concentric ring frame and cooperating with the vertical rod. The inner surface of the guide sleeve is provided with a damping layer.

[0011] The beneficial effects of this utility model are: On the one hand, the oil in the test tube can be heated using a heating container, and the oxidative stability of the oil can be tested by measuring the heating and temperature changes. On the other hand, the test tube in the heating container can be irradiated with ultraviolet or visible light using a ring lamp to promote the auto-oxidation of lipids, thus achieving the purpose of testing the oxidative stability of oils by changing the light conditions. This invention takes into account the determination of the effects of temperature and light conditions on the oxidative stability of oils, further meeting the testing requirements. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the structure of this utility model; Figure 2 yes Figure 1 Top view of the concentric ring frame.

[0013] In the diagram: 1. Expanding gland, 2. Longitudinal push-pull cylinder, 3. First air inlet pipe, 4. Positioning cap, 5. Exhaust port, 6. Insulating packing, 7. Second air inlet pipe, 8. Cover plate, 9. Electrode, 10. Measuring container, 11. Conductivity meter, 12. Base plate, 13. Upright rod, 14. Guide sleeve, 15. Ring lamp assembly, 16. Transparent wall cylinder, 17. Heater, 18. Thermally conductive base, 19. Test tube, 20. Concentric ring frame. Detailed Implementation

[0014] The present invention will be described in detail with reference to the accompanying drawings.

[0015] like Figure 1 , Figure 2 As shown, the oil oxidation stability testing device includes a base plate 12, a heating container, a measuring container 10, a test tube 19 disposed in the heating container, an electrode 9 disposed in the measuring container 10, and a conductivity meter 11 connected to the electrode 9.

[0016] The heating container comprises a heat-conducting base 18, a transparent wall cylinder 16 located on the upper part of the heat-conducting base 18, and an expanded diameter cap 1 located at the upper end of the transparent wall cylinder 16. A heater 17, which is in contact with the heat-conducting base 18, is embedded in the base plate 12. The heating container contains a heating medium solution to achieve water bath heating of the test tube 19.

[0017] The test tube 19 is provided with a positioning cap 4 at its upper end. The positioning cap 4 is provided with an exhaust port 5 and a first air inlet pipe 3 leading to the lower part of the test tube 19. The expansion cap 1 is provided with a through hole corresponding to the test tube 19. The expansion cap 1 is provided with a groove recessed into the upper opening of the heating container. The through hole is located on the bottom surface of the groove. The positioning cap 4 is located in the groove. The groove is provided with heat-insulating filler 6 surrounding the positioning cap.

[0018] A longitudinal push-pull cylinder 2 is fixed to one side of the top surface of the expanded diameter cap 1. A concentric ring frame 20 is provided on the outer side of the transparent wall cylinder 16. The top surface of the concentric ring frame 20 is connected and fixed to the lower end of the cylinder rod of the longitudinal push-pull cylinder 2. An annular light group 15 facing the transparent wall cylinder 16 is fixed on the inner ring surface of the concentric ring frame 20. A longitudinal guide assembly is provided between the concentric ring frame 20 and the expanded diameter cap 1. The longitudinal guide assembly consists of a vertical rod 13 fixed to the lower surface edge of the expanded diameter cap 1 and a guide sleeve 14 provided on the top surface edge of the concentric ring frame 20 and cooperating with the vertical rod 13. A damping layer is provided on the inner surface of the guide sleeve 14.

[0019] The cover plate 8 of the measuring container 10 is fixed with a second air intake pipe 7 that communicates with the exhaust port 5, and the center of the cover plate 8 is provided with a positioning hole corresponding to the upper end of the electrode 9.

[0020] Working principle: 1. Clean air enters the oil sample in test tube 19 through the first air inlet pipe 3, accelerating the oxidation of glycerol fatty acid esters and producing volatile organic acids. The air carries the volatile organic acids through the exhaust pipe 5 to the second air inlet pipe 7, and enters the measurement solution in the measuring container 10. The volatile organic acids dissolve in the measurement solution and ionize into ions under the action of electrode 9, thereby changing the conductivity of the solution. The conductivity meter 11 continuously measures the conductivity, providing data support for the determination of the oxidative stability of oils.

[0021] 2. Adjust the heating temperature of heater 17 and test the change in conductivity by heating and temperature changes.

[0022] 3. The longitudinal push-pull cylinder 1 pushes the concentric ring frame 20 downward, so that the ring lamp group 15 reaches the height of the oil sample in the test tube 19, and irradiates the oil sample with ultraviolet light to promote the automatic oxidation of lipids. The change in conductivity is tested by changing the light intensity.

[0023] The embodiments of this utility model have been described in detail above, but the content described is only a preferred embodiment of this utility model and should not be considered as limiting the scope of implementation of this utility model. All equivalent changes and improvements made within the scope of this utility model should still fall within the scope of this utility model.

Claims

1. A device for determining the oxidative stability of oils and fats, comprising a base plate, a heating container, a measuring container, a test tube disposed in the heating container, an electrode disposed in the measuring container, and a conductivity meter connected to the electrode, characterized in that: The heating container consists of a heat-conducting base, a transparent wall cylinder located on the upper part of the heat-conducting base, and an expanded diameter cap located at the upper end of the transparent wall cylinder. A longitudinal push-pull cylinder is fixed to one side of the top surface of the expanded diameter cap. A concentric ring frame is provided on the outer side of the transparent wall cylinder. The top surface of the concentric ring frame is connected and fixed to the lower end of the cylinder rod of the longitudinal push-pull cylinder. A ring-shaped light assembly facing the transparent wall cylinder is fixed on the inner ring surface of the concentric ring frame. A longitudinal guide assembly is provided between the concentric ring frame and the expanded diameter cap. A through hole corresponding to the test tube is provided on the expanded diameter cap. A positioning cap is provided at the upper end of the test tube. The positioning cap is provided with an exhaust port and a first air inlet pipe leading to the lower part of the test tube. A second air inlet pipe communicating with the exhaust port is fixed on the cover plate of the measuring container.

2. The apparatus for determining the oxidative stability of oils and fats according to claim 1, characterized in that: The expanded diameter cap has a groove recessed into the upper opening of the heating container, the through hole is located on the bottom surface of the groove, the positioning cap is located in the groove, and the groove is provided with heat-insulating filler surrounding the positioning cap.

3. The apparatus for determining the oxidative stability of oils and fats according to claim 1, characterized in that: A heater is embedded in the base plate and is attached to the heat-conducting base.

4. The apparatus for determining the oxidative stability of oils and fats according to claim 1, characterized in that: The heating container contains a heating medium solution.

5. The apparatus for determining the oxidative stability of oils and fats according to claim 1, characterized in that: The longitudinal guide assembly consists of a vertical rod fixed to the edge of the lower surface of the expanded diameter cap and a guide sleeve located at the edge of the top surface of the concentric ring frame and cooperating with the vertical rod. The inner surface of the guide sleeve is provided with a damping layer.

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