A device for measuring oral tribological properties and a method of using the same

Abstract

The present invention provides an oral tribological property measuring device and a method for using the same. The device comprises a pestle, a dynamic sealing assembly at the upper end of a cavity, a cavity, and a static sealing sheet at the lower end of the cavity. The pestle comprises a torque measuring section, a pressure measuring section, a (non-magnetic) external spline section, and a ball clamp, and the pestle can move up and down and rotate; the dynamic sealing assembly at the upper end of the cavity comprises a set screw, a sealing ring, a connecting sleeve, a bellows, and a dynamic sealing sheet at the upper end of the cavity with an internal spline hole; the cavity comprises an upper section, a middle section, and a lower section of the cavity, and a lower clamp is arranged inside the lower section of the cavity; the static sealing sheet at the lower end of the cavity is connected to the lower part of the cavity by a rivet and can rotate around the rivet; a solid phase microextraction probe and a temperature measuring probe are arranged on one side of the uppermost part of the middle section of the cavity. The device can simulate the oral environment, measure the tribological properties of food during oral processing, and simultaneously observe the changes in the microstructure of the food in real time and measure the release characteristics of the corresponding flavor.

Description

Technical Field

[0001] The invention belongs to the technical field of experimental equipment, and in particular relates to an oral tribological property measuring device and a use method thereof. Background Art

[0002] Food is both a necessary and a hobby consumer product. Its sensory attributes such as color, aroma, taste, shape, texture, and mouthfeel significantly affect its quality. Sensory evaluation is one of the most important means of evaluating food quality. However, sensory evaluation methods have defects such as strong subjectivity and poor repeatability, and are easily affected by human factors such as sensory fatigue, resulting in unstable reliability of the results. In order to establish a quantitative evaluation method for food sensory properties, researchers have used materials science methods and techniques to conduct in vitro tests and analyses on the texture, rheology, and flavor composition of food. However, the results obtained have never been able to fully fit the results of sensory tests. Thanks to the introduction of the concept of oral food processing and the vigorous development of oral processing tribology in the past decade, researchers have gradually realized that the sensory perception of food is closely related to the tribological properties during oral processing.

[0003] Oral food processing is a complex dynamic perception process, during which a series of physical and chemical changes occur. Among them, the surface friction caused by the relative movement between food and the oral surfaces such as the palate and tongue is considered to be an important mechanism for oral texture perception. In addition, whether food flavor substances can be fully released and perceived is also affected by food texture. Therefore, it is necessary to simulate the oral environment and measure the oral tribological properties and the concentration of flavor substances during oral processing in order to accurately evaluate the perceived sensory perception characteristics of food and develop foods that suit consumer preferences.

[0004] At present, there are four types of instruments used internationally to measure the tribological properties of the oral cavity, as follows: (1) a tribometer equipped with a friction belt. This device is simple and easy to use, and the data is reliable. However, the friction belt of this device needs to be replaced in real time, and it cannot simulate the human oral cavity well, and lacks speed and temperature control; (2) a tribometer equipped with an optical device. It is connected to a confocal scanning light microscope and can simultaneously observe changes in the microstructure. However, the device must use a transparent fixed surface such as glass, and cannot ideally simulate the friction surface of the oral cavity; (3) a ball-three-plate tribometer, which is a special ball-to-plate fixture attached to the rheometer device. It can fully utilize the advantages of the rheometer's sensitive control and wide torque measurement range, but it cannot simultaneously observe changes in the microstructure; (3) a small traction device, which consists of a rolling ball and a rotating disk. It can perform precise measurements in a completely isolated environment. However, the device is expensive and requires very demanding maintenance. In addition, the only device for measuring flavor release in the oral cavity is "a device and method for simulating flavor release of liquid food in the oral cavity and retronasal olfaction (CN105548462 B)". However, this patent mainly targets liquid food and does not consider the impact of changes in food texture (tribological properties) on food flavor release. Summary of the invention

[0005] The purpose of the present invention is to provide an oral tribological property measuring device and a method of using the same, which can simulate the oral environment, measure the tribological properties of food during oral processing, simultaneously observe the changes in the microstructure of the food in real time, and measure the release characteristics of the corresponding flavor.

[0006] The purpose of the present invention is achieved through the following technical solutions:

[0007] A device for measuring oral tribological properties, the device comprising a pestle, a dynamic sealing assembly at the upper end of a cavity, a cavity, and a static sealing sheet at the lower end of the cavity, wherein the pestle comprises a torque measuring section, a pressure measuring section, a (non-magnetic) external spline section, and a ball clamp in order from top to bottom, and the pestle can move up and down and rotate under the drive of a power device; the dynamic sealing assembly at the upper end of the cavity comprises a set screw, a sealing ring, a connecting sleeve, a bellows with relatively low rigidity, and a dynamic sealing sheet at the upper end of the cavity with an inner spline hole, wherein the bellows is respectively connected to the connecting sleeve and the dynamic sealing sheet at the upper end of the cavity with the inner spline hole. The movable sealing piece at the upper end of the cavity with the inner spline hole can slide on the (non-magnetic) outer spline section of the pestle rod, and the contact surface with the upper end of the cavity is highly smooth and rotates with the pestle rod; the upper part of the cavity is cylindrical and the lower part is conical, the cylindrical part includes the upper section of the cavity and the middle section of the cavity, the conical part is the lower section of the cavity, and a lower clamp is arranged inside the lower section of the cavity; the static sealing piece at the lower end of the cavity is connected to the lower part of the cavity with a rivet and can rotate around the rivet; and a solid phase microextraction probe is arranged on one side of the uppermost part of the middle section of the cavity, and a temperature measuring probe is arranged on the other side.

[0008] Furthermore, the ball clamp is made of stainless steel, and a part of the ball clamp is provided with knurling.

[0009] Furthermore, the lower clamp is fixed to the bottom of the inner wall of the lower section of the cavity, has an arc-shaped contact surface with the upper clamp, and the material of the lower clamp is polydimethylsiloxane, and the material of the lower section of the cavity is magnetic stainless steel.

[0010] Furthermore, the upper section of the cavity is made of magnetic stainless steel, and the middle section of the cavity is made of non-magnetic stainless steel; an upper electromagnetic coil is wound around the outer side of the upper section of the cavity, and a lower electromagnetic coil is wound around the outer side of the lower section of the cavity.

[0011] Furthermore, the dynamic sealing plate at the upper end of the cavity with the inner spline hole is made of magnetically conductive stainless steel.

[0012] Furthermore, the static sealing sheet at the lower end of the cavity is made of magnetically conductive stainless steel.

[0013] Furthermore, an active ventilation pipe and a passive ventilation pipe are arranged between the upper section of the cavity and the middle section of the cavity, and an electromagnetic valve and a pressure gauge are connected to the outlet of the passive ventilation pipe.

[0014] Furthermore, a hot and cold component is installed on the outer side of the upper cylindrical part of the cavity, and the hot and cold component includes a semiconductor refrigeration device and a radiator.

[0015] Another aspect of the present invention:

[0016] The method for using the above-mentioned oral tribological property measuring device comprises the following steps:

[0017] First, align the static sealing sheet at the lower end of the cavity with the lower section of the cavity, and energize the electromagnetic coil at the lower end of the cavity alone, so that the static sealing sheet at the lower end of the cavity is attracted to the lower section of the cavity; the electromagnetic coil at the upper end of the cavity is not energized, and the pestle is lifted upward to drive the dynamic sealing assembly at the upper end of the cavity to separate from the upper section of the cavity; after adding the object to be tested into the cavity, drop the pestle, and energize the electromagnetic coil at the upper end of the cavity to attract the dynamic sealing sheet at the upper end of the cavity to the upper section of the cavity; thereby forming a closed cavity space;

[0018] Then, under the control of the temperature signal of the temperature measuring probe, positive and negative currents are applied to the hot and cold components to increase or decrease the temperature, so as to achieve a constant temperature of 37°C in the sealed cavity; at the same time, the human breathing process is simulated through active and passive ventilation tubes;

[0019] Third, the pestle rod moves downward under the drive of the power device and gradually extends to the bottom of the cavity below. When the ball fixture contacts the lower fixture, the downward movement stops, and the power device is adjusted to rotate the pestle rod, so that the object to be tested performs friction between the ball fixture and the lower fixture for 0.02 min to 5 min to simulate the chewing action in the mouth;

[0020] Fourth, the flavor substances released during the friction activity are collected by the solid phase microextraction probe;

[0021] Fifth, the electromagnetic coil at the upper end of the cavity and the electromagnetic coil at the lower end of the cavity are powered off, the dynamic sealing assembly at the upper end of the cavity is separated from the upper section of the cavity, the static sealing piece at the lower end of the cavity is separated from the lower section of the cavity, and the static sealing piece at the lower end of the cavity rotates downward around the rivet, and the object to be tested after being processed by friction activity falls onto the glass slide below, and the processed object to be tested is directly observed under the confocal microscope set below; at the same time, the solid phase microextraction probe is taken out, and the composition of the released flavor substances is analyzed by gas phase mass spectrometry.

[0022] Furthermore, when sampling is performed in the fifth step, at each stage of the oral friction rotation, a 5 second pause is performed to release 50 μL of the processed test substance for observation.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] 1. The oral tribological property measuring device of the present invention can simulate the oral environment, measure the tribological properties of food in the oral processing process, and simultaneously observe the changes in the microstructure of food in real time and measure the release characteristics of the corresponding flavor;

[0025] 2. The oral tribological property measuring device of the present invention is not only suitable for the detection of liquid food, but also suitable for the detection of solid and semi-solid food;

[0026] 3. The oral tribological property measuring device of the present invention is changed to a cylindrical sealing device compared with the flat sample loading platform of the traditional ball three-plate tribometer. The upper and lower parts are respectively provided with a dynamic sealing component at the upper end of the cavity and a static sealing piece at the lower end of the cavity. The solid phase micro headspace extraction probe can be inserted to extract the released volatile flavor substances in real time, and then analyze them to instruments such as gas phase mass spectrometry to analyze the release characteristics of flavors during oral processing;

[0027] 4. The oral tribological property measuring device described in the present invention has hot and cold components arranged outside the cavity, and under the control of the temperature signal of the temperature measuring probe, positive and negative currents are applied to the hot and cold components to increase or decrease the temperature, so as to achieve a constant temperature of 37°C in the sealed cavity; at the same time, the human breathing process is simulated by active and passive ventilation tubes; the lower splint is made of polydimethylsiloxane (PDMS) material to simulate the surface of the tongue; the stirring speed of the pestle is controlled by a power device and maintained at 2mm / s-200mm / s to simulate the low-speed stirring speed of the tongue, so as to better simulate the real environment of the oral cavity and make the detection data more accurate and reliable. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a structural schematic diagram of the oral tribological property measuring device of the present invention;

[0029] The pestle rod (1), the torque measuring section (1-1), the pressure measuring section (1-2), the external spline section (1-3), the ball clamp (1-4), the dynamic seal assembly (2) at the upper end of the cavity, the set screw (2-1), the sealing ring (2-2), the connecting sleeve (2-3), the bellows (2-4), the dynamic seal sheet (2-5) at the upper end of the cavity, the cavity (3), the upper section of the cavity (3-1), the middle section of the cavity (3-2), the lower section of the cavity (3-3), and the static seal at the lower end of the cavity Plate (4), rivet (5), active ventilation tube (6), passive ventilation tube (7), solenoid valve (8), barometer (9), electromagnetic coil at the upper end of the cavity (10), electromagnetic coil at the lower end of the cavity (11), temperature measuring probe (12), hot and cold components (13), semiconductor refrigeration device (13-1), radiator (13-2), lower fixture (14), solid phase microextraction probe (15), object to be tested (16), slide glass (17), confocal microscope (18). DETAILED DESCRIPTION

[0030] like Figure 1As shown, this embodiment provides an oral tribological property measuring device, the device includes a pestle rod 1, a dynamic sealing assembly 2 at the upper end of the cavity, a cavity 3, and a static sealing sheet 4 at the lower end of the cavity, wherein the pestle rod 1 includes a torque measuring section 1-1, a pressure measuring section 1-2, a (non-magnetic) external spline section 1-3 and a ball clamp 1-4 from top to bottom, the pestle rod 1 can move up and down and rotate under the drive of the power device, the ball clamp 1-4 is made of stainless steel, and the ball clamp The part is provided with knurling; the upper end dynamic seal assembly 2 of the cavity includes a set screw 2-1, a sealing ring 2-2, a connecting sleeve 2-3, a bellows 2-4 and a dynamic sealing piece 2-5 of the upper end of the cavity with an inner spline hole. The bellows 2-4 has low rigidity and is respectively fixed and sealed with the connecting sleeve 2-3 and the upper end dynamic sealing piece 2-5 of the cavity with an inner spline hole. The upper end dynamic sealing piece 2-5 of the cavity with an inner spline hole can slide on the (non-magnetic) outer spline section 1-3 of the pestle rod 1, and The upper end of the cavity with the inner spline hole is made of magnetic stainless steel. The upper part of the cavity 3 is cylindrical, and the lower part is conical. The cylindrical part includes the upper section 3-1 of the cavity and the middle section 3-2 of the cavity. The conical part is the lower section 3-3 of the cavity. The upper section 3-1 of the cavity is made of magnetic stainless steel, and the middle section 3-2 of the cavity is made of non-magnetic stainless steel. The outer side of the upper section 3-1 of the cavity is wound with the upper electromagnetic coil 10 of the cavity. An electromagnetic coil 11 at the lower mouth of the cavity is wound around the outer side of the lower section 3-3, and a lower clamp 14 is arranged inside the lower section of the cavity. The lower clamp 14 is fixed to the bottom of the inner wall of the lower section of the cavity, and has an arc-shaped contact surface with the upper clamp 14. The material of the lower clamp 14 is polydimethylsiloxane, and the material of the lower section 3-3 of the cavity is magnetic stainless steel; a hot and cold component 13 is installed on the outer side of the upper cylindrical part of the cavity 3, and the hot and cold component includes a semiconductor refrigeration device 13-1 and a radiator 13-2.

[0031] The static sealing piece 4 at the lower end of the cavity is connected to the lower part of the cavity 3 by a rivet 5 and can rotate around the rivet 5. The static sealing piece 4 at the lower end of the cavity is made of magnetic stainless steel; and a solid phase microextraction probe 15 is arranged on one side of the uppermost part of the middle section 3-2 of the cavity, and a temperature measuring probe 12 is arranged on the other side.

[0032] In addition, an active ventilation tube 6 and a passive ventilation tube 7 are arranged between the upper section 3-1 and the middle section 3-2 of the cavity, and the outlet of the passive ventilation tube is connected to a solenoid valve 8 and a barometer 9. The active ventilation tube 6 and the passive ventilation tube 7 can simulate the airflow generated by human breathing in the oral cavity.

[0033] The method for using the oral tribological property measuring device comprises the following steps:

[0034] First, align the static sealing sheet 4 at the lower end of the cavity with the lower section of the cavity, and energize the electromagnetic coil 11 at the lower end of the cavity alone, so that the static sealing sheet 4 at the lower end of the cavity is attracted to the lower section 3-3 of the cavity; the electromagnetic coil 10 at the upper end of the cavity is not energized, and the pestle rod is lifted upward to drive the dynamic sealing assembly 2 at the upper end of the cavity to separate from the upper section 3-1 of the cavity; after adding the object to be tested into the cavity 3; drop the pestle rod, and energize the electromagnetic coil 10 at the upper end of the cavity, so that the dynamic sealing sheet 2-5 at the upper end of the cavity is attracted to the upper section 3-1 of the cavity; thereby forming a closed cavity space;

[0035] Then, under the control of the temperature signal of the temperature measuring probe 12, positive and negative currents are applied to the hot and cold components 13 to increase or decrease the temperature, so as to achieve a constant temperature of 37°C in the sealed cavity; at the same time, the active ventilation tube 6 and the passive ventilation tube 7 are used to simulate the human breathing process;

[0036] Third, driven by the power device, the pestle rod 1 moves downward and gradually extends to the bottom of the cavity below. When the ball clamps 1-4 contact the lower clamp 14, the downward movement is stopped, and the power device is adjusted to rotate the pestle rod 1. The stirring speed is maintained at 2mm / s-200mm / s, so that the object to be tested performs friction between the ball clamps 1-4 and the lower clamp 14 for 0.02min-5min to simulate the chewing action in the mouth;

[0037] Fourth, while the friction activity is being carried out, the flavor substances released during the friction activity are collected by the solid phase microextraction probe 15;

[0038] Fifth, the electromagnetic coil 10 at the upper mouth of the cavity and the electromagnetic coil 11 at the lower mouth of the cavity are powered off, the dynamic sealing assembly 2 at the upper end of the cavity is separated from the upper section 3-1 of the cavity, the static sealing piece 4 at the lower end of the cavity is separated from the lower section 3-3 of the cavity, and the static sealing piece 4 at the lower end of the cavity rotates downward around the rivet, and the object to be tested 16 treated by friction activity falls onto the glass slide 17 below, and the microstructure of the treated object to be tested is directly observed in real time under the inverted confocal microscope 18 below; at the same time, the solid phase microextraction probe 15 is taken out, and the composition of the released flavor substances is analyzed by gas phase mass spectrometry.

[0039] Furthermore, when sampling, at each stage of oral friction and rotation, a 5-s pause was performed to release 50 μL of the processed test substance for observation.

Claims

1. An oral tribological property measuring device, comprising a pestle (1), a dynamic sealing assembly (2) at the upper end of a cavity, a cavity (3), and a static sealing sheet (4) at the lower end of the cavity, characterized in that: The pestle rod (1) comprises, from top to bottom, a torque measuring section (1-1), a pressure measuring section (1-2), an external spline section (1-3) made of a non-magnetic material, and a spherical fixture (1-4); the pestle rod (1) can move up and down and rotate under the drive of a power device; the cavity upper end dynamic seal assembly (2) comprises a set screw (2-1), a sealing ring (2-2), a connecting sleeve (2-3), a bellows (2-4), and a cavity upper end dynamic seal sheet (2-5) with an inner spline hole; the bellows (2-4) is respectively fixed to and sealed with the connecting sleeve (2-3) and the cavity upper end dynamic seal sheet (2-5) with an inner spline hole; The dynamic sealing sheet (2-5) at the upper end of the cavity of the inner spline hole can slide on the outer spline section (1-3) of the pestle rod (1) and rotate with the pestle rod; the upper part of the cavity (3) is cylindrical and the lower part is conical, the cylindrical part includes the upper section (3-1) of the cavity and the middle section (3-2), the conical part is the lower section (3-3), and a lower clamp (14) is arranged inside the lower section; the static sealing sheet (4) at the lower end of the cavity is connected to the lower part of the cavity (3) by a rivet (5) and can rotate around the rivet (5); and a solid phase microextraction probe (15) is arranged on one side of the uppermost part of the middle section (3-2) of the cavity, and a temperature measuring probe (12) is arranged on the other side; The spherical clamp (1-4) is partially provided with knurling; the lower clamp (14) is fixed to the bottom of the inner wall of the lower section of the cavity, and the material of the lower clamp (14) is polydimethylsiloxane; An upper electromagnetic coil (10) is wound around the outer side of the upper cavity section (3-1), and an lower electromagnetic coil (11) is wound around the outer side of the lower cavity section (3-3), and the upper and lower electromagnetic coils can be energized respectively; An active ventilation pipe (6) and a passive ventilation pipe (7) are arranged between the upper section (3-1) of the cavity and the middle section (3-2) of the cavity, and a solenoid valve (8) and a pressure gauge (9) are connected to the outlet of the passive ventilation pipe; A hot and cold component (13) is installed outside the upper cylindrical portion of the cavity (3), and the hot and cold component comprises a semiconductor refrigeration device (13-1) and a radiator (13-2).

2. The oral tribological property measuring device according to claim 1, characterized in that: The upper end dynamic sealing plate (2-5) of the cavity with an inner spline hole, the upper section (3-1) of the cavity, the lower section (3-3) of the cavity, and the lower end static sealing plate (4) of the cavity are all made of magnetically conductive stainless steel.

3. The oral tribological property measuring device according to claim 1, characterized in that: The ball clamp (1-4) is made of stainless steel, and the middle section of the cavity (3-2) is made of non-magnetic stainless steel.

4. A method for using the oral tribological property measuring device according to any one of claims 1 to 3, characterized in that: The steps of the method of use are: First, the static sealing sheet (4) at the lower end of the cavity is aligned with the lower section of the cavity, and the electromagnetic coil (11) at the lower end of the cavity is powered on separately, so that the static sealing sheet (4) at the lower end of the cavity is attracted to the lower section (3-3); the electromagnetic coil (10) at the upper end of the cavity is not powered on, and the pestle rod is lifted upward to drive the dynamic sealing assembly (2) at the upper end of the cavity to separate from the upper section (3-1); after adding the object to be tested into the cavity (3); the pestle rod is dropped, and the electromagnetic coil (10) at the upper end of the cavity is powered on, so that the dynamic sealing sheet (2-5) at the upper end of the cavity is attracted to the upper section (3-1); thereby forming a closed cavity space; Then, under the control of the temperature signal of the temperature measuring probe (12), positive and negative currents are applied to the hot and cold components (13) to increase or decrease the temperature, so as to achieve a constant temperature of 37° C. in the sealed cavity; at the same time, the breathing process of a person is simulated through the active ventilation tube (6) and the passive ventilation tube (7); Third, the pestle rod (1) moves downward under the drive of the power device and gradually extends to the bottom of the cavity below. When the spherical clamp (1-4) contacts the lower clamp (14), the downward movement stops, and the power device is adjusted to rotate the pestle rod (1), so that the object to be tested performs friction between the spherical clamp (1-4) and the lower clamp (14) for 0.02 minutes to 5 minutes, so as to simulate the chewing action in the oral cavity; Fourth, while the friction activity is being carried out, the flavor substances released during the friction activity are collected by the solid phase microextraction probe (15); Fifth, the electromagnetic coil (10) at the upper end of the cavity and the electromagnetic coil (11) at the lower end of the cavity are powered off, the dynamic sealing assembly (2) at the upper end of the cavity is separated from the upper section (3-1) of the cavity, the static sealing sheet (4) at the lower end of the cavity is separated from the lower section (3-3), and the static sealing sheet (4) at the lower end of the cavity is rotated downward around the rivet, and the object to be tested (16) after being processed by the friction activity falls onto the glass slide (17) below, and the microscopic structure of the object to be tested after the processing is directly observed in real time under the inverted confocal microscope (18) below; at the same time, the solid phase microextraction probe (15) is taken out and the composition of the released flavor substances is analyzed by gas phase mass spectrometry.

5. The method for using the oral tribological property measuring device according to claim 4, characterized in that: When sampling in the fifth step, at each stage of oral friction and rotation, pause for 5 seconds and release 50 μL of the processed test substance for observation.

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