Quantifying device for post-nasal aroma concentration, sensing threshold determination method and application

Abstract

The invention relates to the technical field of flavor science and sensory detection, and provides a quantifying device for post-nasal aroma concentration, a sensing threshold determination method and application. The quantitative device comprises a nasal catheter, a flow divider, a dryer, an aroma trapping structure and analysis equipment, and can be used for specially collecting aroma released by a nasal passage in the oral cavity processing process and carrying out concentration quantitative analysis. According to the quantitative device expansion method for the post-nasal aroma concentration, by establishing an aroma post-nasal perceptual concentration and perceptual intensity scoring model, the scientific determination of the lower limit perceptual concentration and the upper limit perceptual concentration of target aroma is realized. Furthermore, the optimal adding proportion interval of the aroma components in the product is deduced in combination with the perception difference of people, and is used for guiding formula optimization and establishment of sensory evaluation standards. According to the invention, controllable quantitative sampling and sensing of the afternose path aroma are realized, the flavor regulation and control efficiency and sensory quality of products such as food, spices and medicines are improved, and the afternose path aroma sensing device has wide application value.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of food science, sensory analysis technology and detection instruments, in particular to a device for quantifying the concentration of postnasal aroma and a method for determining the perception threshold, which belongs to the special sensory detection technology in the field of flavor science and odor detection technology. The present application also relates to the application of the device and the detection method in aspects including but not limited to food formula design, aroma adjustment of edible daily necessities, spice development or evaluation of the taste of medicine, and the establishment of odor evaluation standards for food, edible daily necessities, spices or other substances that can be perceived by the postnasal cavity. BACKGROUND

[0002] Aroma perception is an important factor in the design and quality evaluation of products such as food, spices and medicine, which is produced through the synergistic effect of chemical stimulation of aroma compounds and human physiology and psychology. Aroma perception includes two independent paths: the anterior nasal cavity (orthonasal cavity) and the posterior nasal cavity (retro-nasal cavity). The anterior nasal cavity path mainly absorbs aroma molecules in the environment through the nostrils to form perception, while the posterior nasal cavity path delivers aroma to the nasopharynx through the back of the mouth during oral processing, and is perceived by the olfactory epithelium in the posterior nasal cavity area. Compared with the anterior nasal cavity perception, the posterior nasal cavity aroma perception is the main channel for humans to obtain flavor information during eating, and has a more direct impact on food acceptance, sensory enjoyment and consumer behavior.

[0003] The importance of posterior nasal cavity aroma perception is increasingly recognized. Studies have shown that the posterior nasal cavity pathway plays a major role in flavor recognition during eating and is one of the core sources of food "delicious" experience. This perception process interacts with taste, oral touch and other multiple senses, which can significantly enhance the perception of salty, sweet and other flavors of food. More importantly, posterior nasal cavity aroma perception is closely related to olfactory cognitive health, and its abnormal performance can be used as a potential biomarker for various diseases such as neurodegenerative diseases and respiratory diseases. At the same time, this perception path has guiding significance for food formula design, spice development and personalized nutrition regulation. Therefore, accurately grasping the release and perception mechanism of the posterior nasal cavity aroma has important application value for the food, spice and medicine industries to improve the flavor quality of products.

[0004] Currently, the detection and analysis methods for the aroma in the back of the nose mainly use online or offline technical means such as gas chromatography-mass spectrometry (GC-MS), proton transfer reaction mass spectrometry (PTR-MS), selected ion flow tube mass spectrometry (SIFT-MS) and atmospheric pressure chemical ionization mass spectrometry (APCI-MS). These methods usually collect volatile aroma components in the exhaled gas in the nasal cavity to analyze the types and contents of the aroma, but still have the following limitations: (1) it is difficult to effectively distinguish the airflow of the front and back of the nose during the sampling process, and the front of the nose is easily disturbed, resulting in the aroma perception information in the back of the nose being covered; (2) the existing technology focuses on the qualitative analysis of the aroma components in the back of the nose, and lacks a special detection scheme that can directly quantify the concentration change of the aroma in the back of the nose; (3) the current sensory evaluation of the aroma perception in the back of the nose is limited to mixed aroma, and relies on the subjective description of the subjects, lacking a scientific, objective and standardized quantitative analysis system for the single target aroma in the back of the nose, which is difficult to meet the needs of product flavor development, quality control and standard setting; (4) more importantly, the existing technology cannot accurately determine the perception threshold of the aroma in the back of the nose, and lacks a repeatable and quantifiable measurement method for the relationship between the intensity of the aroma perception and the concentration in the back of the nose, thereby restricting the further development and practical application of aroma perception research.

[0005] In summary, the existing aroma detection technology in the back of the nose cannot accurately, dynamically and objectively monitor the aroma concentration in the back of the nose, and cannot effectively measure the perception threshold. Therefore, it is urgent to develop a quantitative detection method and supporting detection device specifically for the back of the nose, to realize the objective evaluation and standardized measurement of the aroma in the back of the nose, and to support the development of product formula, the improvement of palatability and the establishment of sensory evaluation standards in the fields of food, spices and drugs. SUMMARY

[0006] One of the purposes of the present application is to provide a quantitative device for the aroma concentration in the back of the nose to solve the key problems in the prior art, specifically including: the sampling process of the existing aroma detection equipment is complicated, and it is difficult to realize dynamic monitoring of the aroma release during oral processing; in addition, the traditional collection method cannot distinguish the front and back of the nose, and is easily disturbed by the gas in the front of the nose, resulting in the inability to accurately collect the aroma information in the back of the nose.

[0007] Therefore, the present application constructs a quantitative device for the aroma concentration in the back of the nose with reasonable structure, clear path and dynamic shunting and directional trapping function, which can collect the aroma samples released through the back of the nose during the oral processing of the subjects, and realize the quantitative analysis of the concentration, thereby providing technical support for the subsequent aroma perception threshold research, flavor evaluation and product sensory optimization.

[0008] The quantitative device for the concentration of the postnasal aroma includes a postnasal aroma collecting device and a postnasal aroma analyzing device; the postnasal aroma collecting device includes a nasal catheter, a dryer, a flow divider, an aroma capturing structure and a plurality of air guide tubes; the flow divider includes an air inlet tube, a plurality of air outlet tubes and a plurality of valves arranged on the air outlet tubes respectively; the aroma capturing structure includes a first one-way valve, an aroma capturing tube and a waste gas collecting bag, the inlet of the first one-way valve is connected with the air outlet tube of the flow divider through an air guide tube, the outlet of the first one-way valve is connected with the air inlet of the aroma capturing tube through an air guide tube, and the air outlet of the aroma capturing tube is connected with the waste gas collecting bag; the nasal catheter includes nasal insertion segments inserted into two nostrils respectively, the two nasal insertion segments are connected with one end of the dryer through air guide tubes, the other end of the dryer is connected with the air inlet end of the flow divider through an air guide tube, and the plurality of air outlet ends of the flow divider are connected with the inlets of the plurality of first one-way valves respectively.

[0009] The test material is placed in the mouth, the lips and the nasal breathing passage are closed, the test material is processed through the oral cavity, the test gas is formed in the oral cavity and the pharyngeal cavity, the valve on one of the air outlet tubes of the flow divider is opened, and then the test gas is exhaled through the postnasal path and the nasal insertion segment, and the test gas sequentially passes through the dryer and the flow divider into one of the aroma capturing structures, wherein the aroma capturing tube adsorbs the target aroma in the test gas, and the remaining gas is discharged into the waste gas collecting bag to complete one gas collection; the process is continued for several times, the valves on the remaining different air outlet tubes of the flow divider are controlled, and the remaining several aroma capturing structures are used to sequentially and continuously collect the gases in different processes.

[0010] The postnasal aroma collecting device of the device precisely guides the test aroma discharged from the oral cavity through the postnasal path into the aroma capturing tube while discharging the non-target aroma and the remaining gas into the waste gas collecting bag through the closed nasal guide path, thereby realizing effective target aroma capture. The dryer is used to reduce water vapor interference and improve capture efficiency, the flow divider is used in cooperation with the plurality of aroma capturing structures to realize multi-stage continuous aroma collection. The postnasal aroma collecting device of the present application clearly defines the postnasal path of the target aroma collection, avoids the interference of the antenosal passage, supports continuous sampling, captures the aroma released in different stages, improves the timing control and quantitative accuracy of aroma collection, and is beneficial to dynamic and quantitative analysis.

[0011] Preferably, it further includes a flexible positioning sheet and a pull rope limiting the flexible positioning sheet, the nasal catheter further includes a transverse segment arranged transversely, the transverse segment is fixed on the flexible positioning sheet, and the flexible positioning sheet and the transverse segment are limited at the philtrum by the pull rope.

[0012] By setting a transverse section in the nasal catheter, the transverse section is fixed to the flexible positioning sheet and is limited at the philtrum by a pull rope, ensuring that the bilateral nasal insertion sections are stable in position and have good air tightness during the experiment; thereby avoiding displacement or loosening of the nasal catheter during the experiment, ensuring the consistency of sampling; at the same time, the transverse section is limited by the pull rope to improve the nasal cavity sealing, reduce external air interference with the sampling gas, and help improve the convenience of repetitive operation of the subject.

[0013] Preferably, the controller is further provided, and each of the valves is an electromagnetic valve controlled by the controller.

[0014] The valves on the multiple shunt exhaust pipes are designed as electromagnetic valves, which are controlled by the controller to open and close, thereby realizing sequential gas collection and path switching in different stages of the experiment. The degree of automation is high, which improves the controllability of the sampling process; reduces human operation errors and enhances the reproducibility of the experiment. The controller of the application adopts a PLC controller. The related processes, transmissions and receptions of the controller are conventional technical choices for those skilled in the art, belong to the prior art, and do not require creative labor to obtain the technical solution, which is not the object of protection of the application.

[0015] Preferably, the gas pipe clamp is further provided, and the gas pipe clamp is arranged on the gas guide pipe between the nasal insertion section and the dryer to control the opening and closing of the gas guide pipe.

[0016] The gas pipe clamp is arranged between the nasal insertion section and the dryer, which can be manually or automatically controlled to control the opening and closing of the gas flow, as a rhythm control means, to realize temporary closure of the aroma flow path, facilitate safe operation or flow calibration; at the same time, when the subject inhales, the gas in the gas guide pipe and other structures is prevented from being inhaled into the nasal cavity, avoiding gas leakage or sampling error in the non-experiment stage.

[0017] Preferably, a second one-way valve for breathing air supplement is further arranged on the pipeline between the nasal insertion section and the dryer. The second one-way valve is generally arranged on the transverse section.

[0018] The second one-way valve is arranged on the transverse section between the nasal insertion section and the dryer, which is used to guide external clean air into the system to maintain the smooth breathing of the subject or realize intermittent air supplement in a specific experimental process. In the experiment, air pressure balance is facilitated, negative pressure is avoided, and experiment comfort and safety are ensured.

[0019] Preferably, a nasal plug for sealing the nostrils is arranged on the outer wall of each of the two nasal insertion sections.

[0020] The nasal congestion covers the outer wall of the nasal plug section, closes the front nasal passage by fitting the outer edge of the nostril, avoids external air from entering, thereby ensuring that the aroma gas only enters the post-nasal aroma collection device from the post-nasal path, effectively shielding the front nasal cavity inhalation path, excluding the interference of the post-nasal collection path, thereby improving the purity and representativeness of the aroma sample, and ensuring that the post-nasal path collection and analysis data have independent repeatability.

[0021] The application is used for the quantitative device of the post-nasal aroma concentration, the aroma collection path, the flow control, the aroma capture and the waste gas collection are organically integrated through the post-nasal aroma collection device, the post-nasal aroma concentration is collected and quantitatively analyzed in a specific direction through the post-nasal aroma collection device and the post-nasal aroma analysis device, thereby realizing the perception data of the aroma in the real eating scene, which is repeatedly, controllably and accurately quantified; a systematic platform basis is provided for aroma threshold determination, sensory evaluation, formula optimization, thereby promoting the in-depth development of flavor science and sensory standard research.

[0022] The application also relates to a perception threshold determination method for the post-nasal aroma concentration using the above device, which is mainly used for accurately determining the sensory threshold of the post-nasal aroma concentration.

[0023] The perception threshold determination method for the post-nasal aroma concentration comprises the following steps:

[0024] S1, preparing a plurality of to-be-measured materials M containing target aroma substance step concentrations i (i=1, 2,..., r);

[0025] S2, obtaining the lower limit of the post-nasal perception threshold

[0026] St1, a plurality of evaluators P e (e=1, 2,..., k) respectively for a plurality of to-be-measured materials M i are processed and evaluated; wherein each evaluator processes and realizes gas capture according to the plurality of aroma capture structures in the above device for each to-be-measured material; the post-nasal gas generated in the capture process is sequentially adsorbed through the aroma capture pipe, and the residual gas is introduced into the waste gas collection bag;

[0027] St2, after each evaluator completes each aroma capture step for each to-be-measured material, the mass value of the adsorbed target aroma in the aroma capture pipe is measured as m ij (i=1, 2,..., r; j=1, 2,..., q), and the gas volume V ij (i=1, 2,..., r; j=1, 2,..., q) in the corresponding waste gas collection bag is measured, thereby calculating the concentration value C of the post-nasal aroma in each step ij(i = 1, 2, …, r; j = 1, 2, …, q); while recording whether the evaluator can perceive the target aroma at each aroma concentration, and making a "yes / no" judgment on the perception result, and counting the number of "yes" judgments X and the number of "no" judgments Y of all evaluators for the same target material in the same level aroma capture step;

[0028] S3, based on a certain confidence level, the upper limit P of the confidence interval of the theoretical number of evaluators whose perception rate of the same target material in the same level aroma capture step is significantly higher than the chance level is obtained according to the confidence interval calculation formula s ; wherein the chance level is defined as the expected probability benchmark (50%) of the "yes / no" judgment of the perception result under purely random conditions;

[0029] S3, based on a certain confidence level, the upper limit P of the confidence interval of the theoretical number of evaluators whose perception rate of the same target material in the same level aroma capture step is significantly higher than the chance level is obtained according to the confidence interval calculation formula f (f = 1, 2, …, r × q), wherein the actual perception rate calculation formula is as shown in formula (1), and the actual perception rate P f is compared with the size relationship of the upper limit P s of the confidence interval, all P s greater than the upper limit P f of the confidence interval are counted, and the average value of all the postnasal target aroma concentrations corresponding to each P f is calculated The minimum value is the lower limit of the postnasal perception threshold of the target aroma.

[0030] p f = X / (X+Y) …… (1);

[0031] S3, obtaining the upper limit of the postnasal perception threshold

[0032] Stp1, obtaining the perception intensity score S ij (i = 1, 2, …, r; j = 1, 2, …, q) of each evaluator corresponding to a plurality of different postnasal target aroma concentrations, arranging the aroma concentration values and the corresponding perception intensity scores in ascending order of concentration, and forming a data set of the postnasal target aroma concentration-perception intensity score relationship of each evaluator;

[0033] Stp2, based on the individual postnasal target aroma concentration-perception intensity score relationship data set of each evaluator, a nonlinear function is used to fit the relationship between the postnasal target aroma concentration and the perception intensity score, and the nonlinear function is a Logistic curve, a Sigmoid function or other concentration-response relationship model; after the fitting is completed, the growth rate of the perception intensity score is calculated, and the growth rate can be represented by the derivative of the fitting function or the change difference of the scores at adjacent concentrations;

[0034] Stp3, identifying the score platform segment when the score growth rate is less than a preset threshold value, the preset threshold value being defined as a continuous score increment being less than 0.3 or a continuous growth rate being less than 5%; determining a minimum aroma concentration value corresponding to when entering the platform segment as a post-nasal perception threshold upper limit of the evaluator;

[0035] Stp4, statistically processing post-nasal perception threshold upper limit data of all evaluators, and calculating the post-nasal perception threshold upper limit by using an arithmetic mean, a median or a truncated mean after removing extreme values.

[0036] By preparing a series of target aroma concentration materials in a ladder distribution, the release state of different aroma concentrations under real conditions can be simulated, and step-by-step aroma stimulation intensity can be provided to the evaluators, which is conducive to capturing the perception critical point.

[0037] The aroma collected by the evaluators through the post-nasal passage is collected step by step by using a matching post-nasal aroma collection device, and the target aroma is adsorbed by the aroma capture tube. The actual target aroma concentration is measured, and the perception probability is counted in combination with the "yes / no" perception feedback. The relationship between the wald, Wilson Score or Clopper-Pearson confidence interval and the actual perception rate is used to determine the lowest concentration point of the significantly perceived target aroma. The objective and quantitative definition of aroma perception under the post-nasal path is realized. Through the statistical threshold of "significantly higher than the opportunity level", the scientificity and repeatability of the threshold detection are improved, and a stable and reliable reference point is provided for sensory science.

[0038] By recording the perception intensity scores of the evaluators on different concentration samples, a post-nasal target aroma concentration-perception intensity score relationship curve is obtained. The score growth rate is used to set a platform discrimination threshold, and it is judged that the score enters a saturation platform segment when the score increment is continuously less than a certain threshold value (such as 0.3) or the score growth rate is lower than a set proportion (such as 5%). When the perception tends to be saturated, the aroma concentration corresponding to this point is the individual perception threshold upper limit, and the aroma concentration corresponding to the maximum perception capacity of all evaluators is determined, so as to calculate the highest concentration threshold of the post-nasal perception of all evaluators. This method can scientifically identify the saturation value of individual olfactory perception, and avoid problems such as resource waste or sensory fatigue caused by aroma concentration exceeding the perception threshold. Through statistical integration (such as taking an average value or a median) of the maximum threshold values of multiple evaluators, the perception threshold upper limit at the group level is obtained, which provides an upper limit control basis for product design.

[0039] In the individual aroma perception evaluation and threshold upper limit definition, "0.3" and "5%" are used as the judgment standard of the "platform period identification threshold", which directly affects the determination of the post-fitting perception threshold upper limit.

[0040] 0.3 as the incremental threshold of the perceived intensity score refers to the absolute increment of the perceived intensity score between two consecutive concentration points; if the change between scores in several consecutive concentration points is less than 0.3 (such as from 9.2 to 9.4, and then to 9.5), it means that the score enters a plateau; when the growth of the score stagnates or tends to be stable after a certain concentration point, it is considered that "the concentration of the point" is the upper limit of the perception threshold.

[0041] Sources and basis: In sensory science and psychophysics, the perceived difference of score increment is set as the just noticeable difference (JND); 0.3 score units are approximately equivalent to 3% score change in a 10-point system, which is one of the smallest differences that can be stably distinguished by humans; this value is often used in sensory evaluation research as a signal to enter the "plateau" or "tend to saturation".

[0042] 5% as the relative change threshold of the perceived score growth rate refers to the relative change rate of the score with the increase of the concentration; if the score growth rate is continuously lower than 5%, it means that the score almost does not significantly increase with the increase of the concentration, which also belongs to the plateau.

[0043] Sources and basis: 5% is a common relative response saturation threshold in physiological psychology; it is widely used in pharmacological dose-response curves, taste and olfactory perception research; its advantage is that it has the ability to normalize different score benchmarks, and is more suitable for cross-evaluator comparison.

[0044] In practical application, the two methods are often used in combination: if the increment <0.3 and the growth rate <5% are both true, it is considered that the plateau has appeared; therefore, 0.3 and 5% are double standards for judging "score saturation", which are judged from the absolute change and the relative growth dimensions respectively.

[0045] Further, the perception threshold determination method further comprises the step of obtaining a post-nasal target aroma concentration-perceived intensity score relationship data set based on the perceived intensity score, which comprises:

[0046] Step 1, training several evaluators participating in sensory evaluation for post-nasal aroma perception score, only perceiving aroma intensity through the post-nasal path, so that they understand the definition and reference standard of the score scale, i.e. 0 represents complete inability to perceive, the maximum value of the pre-set score scale represents reaching the maximum acceptable perception intensity, and the score between 0 and the maximum value is linearly related to the post-nasal aroma perception intensity; and providing typical samples to establish a score reference; evaluators with abnormal perception scores are excluded;

[0047] Step2、After training, the evaluators successively evaluate the test materials at multiple gradient concentrations. Each evaluation of the test material is followed by j continuous evaluations, and a certain time interval is maintained between each two evaluations to eliminate the adaptation effect;

[0048] Step3、After each evaluation, each evaluator selects the corresponding score on the pre-set scoring scale according to their subjective intensity perception of the target aroma and records it;

[0049] Step4、Collect the perception intensity score recorded by each evaluator and its corresponding post-nasal target aroma concentration value to form a post-nasal target aroma concentration-perception intensity score pair data set as formula (2) for subsequent fitting of the post-nasal target aroma concentration-perception intensity score relationship curve;

[0050] A={(C ij ,S ij )∣i=1,2,...,r; j=1,2,...,q} (2)

[0051] Where C ij represents the aroma concentration of the ith material in the jth aroma release process, and S ij is the corresponding perception intensity score;

[0052] Step5、When continuous scoring abnormalities occur during the scoring process, the relevant data is reviewed or excluded to improve the consistency and reliability of the scoring.

[0053] The scoring process is carried out in a standard sensory analysis room. Each evaluator fasts for at least 1 hour before the experiment, and wears a sealed nasal catheter during the aroma evaluation process to ensure that the gas transmitted through the post-nasal pathway is completely captured.

[0054] Through unified scoring scale training, a linear reference system from 0 (no perception) to maximum perception score is established to ensure consistent understanding of post-nasal perception scores by each evaluator and to ensure the consistency and reliability of perception score data, thereby significantly improving the stability of the fitted model. The established scoring model can be used as a prediction model for product aroma perception to provide quantitative sensory feedback for different formulations or samples.

[0055] Further, the perception threshold determination method further includes an estimation of the post-nasal perception aroma concentration threshold before step S1, and includes the following steps:

[0056] A standard formula base is used as a carrier, and different proportions of target aroma substances are added to the base without changing the proportions of other ingredients, to construct a test sample group with multiple concentration gradients. The addition amount of the aroma substance is increased in concentration gradient, and each level of concentration is a set multiple of the previous level, to cover the possible lower limit or / and upper limit of the post-nasal perception threshold.

[0057] The sensory evaluation personnel trained for post-nasal perception evaluate the sample group one by one through the post-nasal pathway, and based on the perception feedback of the evaluators, the aroma substance concentration corresponding to the sample number first stably perceived by most evaluators is identified, and the lower limit or upper limit of the post-nasal perception threshold of the target aroma is preliminarily set.

[0058] The sample in step St1 is used as the center reference, and the sample refers to the material M to be tested i The median in (i = 1, 2, …, n) is further expanded in concentration gradient before and after it at the same concentration interval to form an aroma concentration sample set containing several levels, thereby covering the concentration range from below the threshold to above the threshold, and providing basic data support for subsequent quantitative analysis.

[0059] The application also relates to the use of the above-mentioned device for determining the post-nasal aroma concentration in the fields of food formula design, in-mouth living product flavoring, spice development or drug taste evaluation, but is not limited thereto.

[0060] Through the application of the device in the fields of food, living products, spices, drugs and the like, scientific regulation of the aroma component concentration in product formulas can be achieved, the aroma release intensity and durability can be optimized, and the sensory experience and consumer acceptance can be improved. At the same time, the device helps to establish a standardized and repeatable sensory evaluation system, supporting the precision of product flavor design and quality control.

[0061] The application also relates to the use of the above-mentioned method for determining the post-nasal aroma concentration in the fields of food formula design, in-mouth living product flavoring, spice development or drug taste evaluation, but is not limited thereto, and is characterized by comprising the following steps:

[0062] Ste1, on the basis of obtaining the lower limit and upper limit of the post-nasal perception threshold of the target aroma, a function relationship model between the actual perception of the target aroma concentration and the perception intensity score is established;

[0063] Ste2, according to the sensory preference, perception intensity score and variability of different groups of people, a clustering analysis, principal component analysis or other statistical modeling method is applied to group and classify the perception data, and a diverse perception response model is constructed;

[0064] Ste3, based on the above threshold interval and the crowd perception model, combined with the release characteristics of the aroma components in the specific material matrix conditions in each to-be-tested formula or product system, the optimal addition proportion interval of the target aroma substance in the formula is deduced, so that the released postnasal target aroma concentration in the product use or intake process is stably within the perception threshold range, and the ideal postnasal aroma perception intensity of the product is ensured;

[0065] Ste4, according to the above optimization ratio result, a formula design reference range of the target aroma and a standardized sensory evaluation model are established, which are used as the basis for product formula optimization and quality control, so as to realize precise regulation of postnasal aroma flavor and improvement of individualized sensory experience.

[0066] Based on the lower limit or / and the upper limit of the postnasal perception threshold, combined with the aroma release characteristics in the actual formula, a corresponding model of perception score-aroma concentration is constructed. The group perception data is used for classification modeling (such as cluster analysis, principal component analysis), and the perception response typing is formed. Finally, the optimal addition concentration interval of the aroma substance in the product is deduced, and a standardized evaluation model is established for subsequent formula reference and quality control. The aroma perception difference for different groups of people is supported, and the formula is optimized individually; the accuracy and economy of the use of aroma substances are improved; a scientific and quantitative flavor standard model is constructed, which promotes the development of the food, spice and medicine industries from experience-based development to data-driven formula design; and a quantifiable decision support tool is provided for the improvement of product palatability and the enhancement of user satisfaction.

[0067] The application provides a quantitative device for postnasal aroma concentration and a perception threshold determination method and application thereof, which has the following remarkable beneficial effects:

[0068] 1. Realize the special collection and concentration quantitative analysis of postnasal aroma: through the construction of a closed nasal catheter system, the cooperation of a shunt and a multi-channel aroma capture structure, the special collection of the postnasal aroma after oral processing is realized, the interference of the antenosal pathway is effectively isolated, and the purity and accuracy of the postnasal cavity aroma data collection are significantly improved.

[0069] 2. Support multi-stage aroma sampling and realize fine perception evaluation of different concentration levels: through the multi-channel shunt structure and multiple independent aroma capture units in the device, multiple stages of postnasal gas samples can be collected in sequence during the same oral processing process. Each capture unit corresponds to different capture time periods or gas flow settings, which helps to construct perception reaction data groups at different concentrations and provide reliable data support for aroma perception threshold and scoring model, so as to realize fine evaluation of postnasal aroma at multiple concentration levels.

[0070] 3. Establish a scientific evaluation mechanism for the perception threshold of aroma: By combining the "yes / no" perception record with the target aroma concentration data, the confidence interval method is used to quantitatively determine the significant perception point, and an objective minimum post-nasal perception concentration threshold evaluation system is constructed, which fills the technical gap that the existing technology cannot quantitatively determine the threshold.

[0071] 4. Support the fitting of perception score curve: By fitting the post-nasal target aroma concentration-perception intensity score data, the score platform section is automatically identified, and the threshold upper limit of the slow growth of perception intensity is determined, so that the upper limit of the perception threshold can be scientifically determined, the aroma usage dose can be optimized, and the post-nasal perception overload and resource waste caused by excessive aroma can be avoided.

[0072] 5. Promote the combination of standardization and individualization of aroma formula design: Based on the collected post-nasal target aroma concentration-perception intensity score data and the perception model of diverse population, the optimal proportion interval suitable for different population can be derived, which can accurately guide the flavor control of product formula such as perfume, food and medicine, and enhance the consumer satisfaction.

[0073] 6. Widely applicable to multiple industry fields: The technology is applicable to food formula design, in-mouth life product aroma design, perfume development, drug taste evaluation and other scenes, promotes the development of flavor science and sensory standard research in the direction of systematization, quantification and individualization, and has wide industrial value.

[0074] In summary, the present application fills the technical gap of quantitative perception analysis of aroma in the post-nasal pathway, realizes the accurate analysis of aroma threshold, and provides strong technical support for the research and development and standard formulation of aroma-related products. BRIEF DESCRIPTION OF DRAWINGS

[0075] The content expressed by each drawing of the specification and the marks in the drawings are briefly explained:

[0076] Figure 1 It is a structural schematic diagram of the process of perceiving the target aroma in the post-nasal pathway of the present application;

[0077] Figure 2 It is a structural schematic diagram of the post-nasal aroma collection device of the embodiment;

[0078] Figure 3 It is a schematic diagram of the acquisition steps for the lower limit of the post-nasal target aroma concentration perception threshold composed of the post-nasal target aroma concentration-perception intensity score data collection (Table A) and the "yes / no" judgment table (B) of the perception result of the embodiment;

[0079] Figure 4 It is a post-nasal aroma perception concentration-perception intensity score fitting graph of the evaluator P1 of the embodiment;

[0080] Wherein: 1 is a nasal catheter; 11 is a nasal insertion section; 12 is a transverse section; 13 is a nasal plug; 2 is a dryer; 3 is a flow divider; 31 is an air inlet pipe; 32 is an air outlet pipe; 33 is a solenoid valve; 34 is a controller; 4 is an aroma capture structure; 41 is a first one-way valve; 42 is an aroma capture pipe; 43 is a waste gas collection bag; 5 is an air guide pipe; 6 is a flexible positioning sheet; 7 is a pull rope; 8 is a tracheal clamp; 9 is a second one-way valve. DETAILED DESCRIPTION

[0081] The application will be further described by non-limiting examples in conjunction with the accompanying drawings. It should be understood, however, that these descriptions are merely examples and are not intended to limit the scope of the application. In addition, in the following description, descriptions of well-known structures and techniques have been omitted to avoid unnecessarily obscuring the concept of the application.

[0082] Example Quantitative detection of postnasal target aroma concentration and obtaining of lower and upper limits of postnasal aroma perception threshold

[0083] [One] Obtaining of lower limit of postnasal target aroma concentration perception threshold

[0084] I. Purpose of the experiment

[0085] Using the quantitative device for postnasal aroma concentration proposed by the application, the postnasal release of 7 gradient orange aroma concentration biscuit samples (M1-M7) during oral processing was studied. Through multiple tests by 30 trained evaluators, aroma capture data were quantitatively obtained, and subjective perception responses were recorded to establish the aroma concentration-perceived intensity score relationship and the lower limit of the perception threshold.

[0086] II. Experimental materials and equipment

[0087] 1. Test materials: 7 types of M1-M7, using standard biscuits as the matrix, adding different concentrations of orange flavor essence, M1 to M7 increasing in concentration by 2 times each time, as shown in Table 1.

[0088] Table 1 Orange flavor essence addition concentration table (unit: μg / g biscuit)

[0089] Test material number Concentration of essence (μg / g) M1 0.5 [M2] 1.0 [M3] 2.0 M4 4.0 [M5] 8.0 M6 16.0 M7 32.0

[0090] 2. Experimental equipment: quantitative device for postnasal aroma concentration

[0091] The quantitative device for postnasal aroma concentration includes postnasal aroma collection equipment and a gas chromatograph-mass spectrometer; as shown in Figure 2As shown, the post-nasal aroma collection device comprises a nasal catheter 1, a dryer 2, a flow divider 3, 9 aroma capture structures 4 and several air guide tubes 5; the flow divider 3 comprises an air inlet tube 31, an air tube clamp 8, 9 air outlet tubes 32 and 9 solenoid valves 33 respectively arranged on the air outlet tubes 32; the aroma capture structure 4 comprises a first one-way valve 41, an aroma capture tube 42 and a waste gas collection bag 43, the inlet of the first one-way valve 41 is connected with the air outlet tube 32 of the flow divider 3 through the air guide tube 5, the outlet of the first one-way valve 41 is connected with the air inlet of the aroma capture tube 42 through the air guide tube 5, and the air outlet of the aroma capture tube 42 is connected with the waste gas collection bag 43; the nasal catheter 1 comprises two nasal insertion sections 11 respectively inserted into two nostrils, the two nasal insertion sections 11 are connected with one end of the dryer 2 through the air guide tube 5, the other end of the dryer 2 is connected with the air inlet end of the flow divider 3 through the air guide tube 5, and the 9 air outlet ends of the flow divider 3 are respectively connected with the inlets of the 9 first one-way valves 41; the air tube clamp 8 is arranged on the air guide tube 5 between the nasal insertion section 11 and the dryer 2, so as to control the on-off of the air guide tube 5.

[0092] The quantitative device for post-nasal aroma concentration further comprises a flexible positioning sheet 6 and a pull rope 7 limiting the flexible positioning sheet 6, and the nasal catheter 1 further comprises a transverse section 12 arranged transversely, the transverse section 12 is fixed on the flexible positioning sheet 6, and the flexible positioning sheet 6 and the transverse section 12 are limited in the philtrum by the pull rope 7. A second one-way valve 9 for breathing air supplement is further arranged on the pipeline between the nasal insertion section 11 and the dryer 2, and the second one-way valve 9 is generally arranged on the transverse section 12. Nasal plugs 13 for sealing the nostrils are respectively arranged on the outer walls of the two nasal insertion sections 11.

[0093] As shown in Figure 1 , 2 , the material to be tested is placed in the mouth, the lips and the nasal breathing passage are closed, and the material to be tested is processed through the oral cavity to form the tested gas in the oral and pharyngeal cavities. The solenoid valve 33 on the first air outlet tube 32 of the flow divider 3 is controlled to be opened by the controller 34, and then the tested gas is exhaled through the post-nasal path and the nasal insertion section 11, and the tested gas enters the first aroma capture structure 4 in sequence through the dryer 2 and the flow divider 3, wherein the aroma capture tube 42 adsorbs the target aroma in the tested gas, and the remaining gas is discharged into the waste gas collection bag 43, so that one gas collection is completed. The process is continued for 8 times, the solenoid valves 33 on the remaining different air outlet tubes 32 of the flow divider 3 are controlled by the controller 34, and the remaining 8 aroma capture structures 4 are used to collect the gas in different processes in sequence.

[0094] The gas guide tube is a plastic tube made of polytetrafluoroethylene, the inner diameter of the cross section of the plastic tube is 5 mm, the total amount of the gas guide tube is 30-50 cm, and the amount of gas in the gas guide tube is 5-10 ml; the amount of gas contained in the waste gas collection bag is 1L-1.5L, the waste gas collection bag is a Tedlar PVF gas sampling bag of Dupont Company, the amount of gas in the gas guide tube has little effect on the overall collected gas volume, so it can be ignored; the aroma adsorption tube is a tenax sampling adsorption tube, which is used to adsorb volatile organic compounds exhaled by the evaluator.

[0095] Device pretreatment: each evaluator wears a sealed nasal catheter; check whether the nasal catheter, desiccator, shunt, aroma capture structure and gas guide tube are well sealed.

[0096] 3. Evaluators: a total of 30, aged between 20-45, all having received training in post-nasal aroma scoring, and having passed the post-nasal path perception test to participate in the experiment.

[0097] III. Experimental procedure

[0098] 1. Experimental preparation:

[0099] All equipment passes the air tightness test; each evaluator wears a sealed nasal catheter, sits stably, and avoids additional interference.

[0100] 2. Estimate the concentration range of orange flavor essence in the biscuit to be tested:

[0101] Using standard formula biscuits as the matrix, without changing the proportion of other ingredients, different proportions of orange flavor essence are added to the biscuits to obtain multiple gradient concentration samples. Exponential increasing concentration design is used initially, i.e. the essence addition amount of each level sample is 5-10 times that of the previous level, so as to cover the potential post-nasal perception threshold limit.

[0102] Through the organization of 30 trained sensory evaluators, the samples in this group are evaluated one by one, and the aroma perception evaluation is carried out only through the post-nasal path. According to the comprehensive evaluation results, it is found that the sample that most evaluators can stably perceive the orange flavor essence for the first time is M4, so the essence concentration corresponding to M4 is preliminarily set as the post-nasal perception threshold limit of the target aroma.

[0103] Taking M4 as the center reference, continue to expand the essence concentration to both sides in equal ratio, and use the ratio gradient design to build lower (M1-M3) and higher (M5-M7) concentration samples, so as to obtain a total of 7 gradient concentration samples M1-M7, covering the concentration range from below the perception threshold to the perceptible state, in order to further accurately determine the post-nasal perception threshold limit.

[0104] 3. Sample testing procedure of the material to be tested:

[0105] Each evaluator tested each of the test materials M1-M7 once.

[0106] Each test step was as follows:

[0107] (1) The evaluator placed the test material (e.g. M1) numbered M i in the mouth, chewed for 20 seconds, exhaled twice, and inhaled through the mouth in between. To prevent inaccurate collection of the exhaled air due to the nasal passage during chewing, the air passage of the dosing device was closed by the air tube clamp as shown in Figure 1 before exhalation, and opened during exhalation.

[0108] (2) When the gas was released actively within 20 seconds, the jth air outlet tube electromagnetic valve of the flow splitter (j = 1-9, sequentially assigned) was opened twice, and the target aroma released through the nasal passage was collected into the aroma collection structure, and the target aroma of the jth tube (stage) of the test material Mi was obtained through the aroma adsorption tube, and the exhaust gas was collected through the exhaust gas collection bag.

[0109] (3) Each evaluator sequentially tested the test samples of M1-M7, and obtained the target aroma collected by the i x j aroma collection structures and the exhaust gas.

[0110] (4) After the collection, the following was recorded:

[0111] Test material number (M i (i = 1, 2, … 7))

[0112] Evaluator (p e (e = 1, 2, … 30))

[0113] Number of flow splitter air outlet tubes (j = 1, 2, … 9)

[0114] Mass of target aroma in aroma collection tube (m ij , unit: μg), mass of target aroma in aroma collection tube (m ij , unit: μg): all volatile organic compounds in the aroma collection tube were desorbed using a thermal desorption instrument or solvent elution, and then the mass of the target aroma was determined by gas chromatography mass spectrometry (GC-MS).

[0115] Gas volume in exhaust gas collection bag (V ij , unit: mL)

[0116] Calculated value of aroma concentration (C ij = m ij / V ij , unit: μg / mL)

[0117] Recorded subjective perception judgment of "yes" or "no" to the perception of the target aroma.

[0118] Give a target aroma perception intensity score (S) ij (0-10 points, 0 for no perception, 10 for extremely strong, accurate to 0.5).

[0119] Data: Each cell is (C ij S ij ), where C ij S represents the aroma concentration obtained and measured for the analyte M at the j-th stage of the i-th material. ij This indicates that the target of C ij The perceived intensity score of the target aroma.

[0120] 4. Data Collection

[0121] Each evaluator's recorded perceived intensity score is paired with its corresponding retronasal target aroma concentration value to form a data pair of retronasal target aroma concentration - perceived intensity score. All evaluators then evaluate each test material M. i Several target aroma concentration-perception intensity score data pairs were perceived and detected, forming 7 datasets for the evaluation of M1-M7, which are represented as shown in Equation (2). Since the lower limit of the retronasal perception threshold of orange aroma was obtained in the perception and detection of M2, the 5 datasets for the evaluation of M3-M7 were omitted. The final data list for the evaluation of M1 and M2 is shown in Tables 2 and 3.

[0122] Table 2. Scoring data of target aroma concentration – perceived intensity obtained by all evaluators after evaluating M1.

[0123]

[0124]

[0125] Table 3. Scoring data of target aroma concentration – perceived intensity obtained by all evaluators after the M2 evaluation.

[0126]

[0127]

[0128] 5. Data Analysis

[0129] (1) Tables 2 and 3 are as follows Figure 3 As shown in Table A, the data obtained by each evaluator in the same aroma capture step for the same test material are arranged sequentially in the same column. Within each column, based on each evaluator's assessment of the perceived intensity of the target aroma, the number of judgments indicating perceived intensity ("yes") is counted as X, and the number of judgments indicating no perceived intensity ("no") is counted as Y. The final statistical results are as follows: Figure 3The actual perception rate of the panelists for the aroma concentration of each column is shown in Table 2 and Table 3, and is denoted as P f The actual perception rate data of each column is shown in Table 2 and Table 3, and the calculation formula of the actual perception rate is shown in formula (1).

[0130] (2) Statistical basis for Wilson confidence interval calculation and significance judgment standard:

[0131] In the sensory evaluation process described in this embodiment, in order to determine whether the panelists have significant perception ability for the target aroma, the Wilson confidence interval method is used for statistical analysis of the "yes / no" perception judgment rate. Under the premise that the sample size (data pair) is 30, assuming that the judgment rate of the panelists for the aroma in a random state is 50% (i.e. the opportunity level), the Wilson confidence interval calculated according to the 95% confidence level is [33.2%, 66.9%]. Therefore, when the actual perception rate exceeds the upper limit of the interval (i.e. 66.9%), it can be considered that the group of aroma samples is significantly perceived by the panelists in the post-nasal pathway, and has statistically significant perceptibility. This standard provides a scientific and objective judgment benchmark for identifying the significant perception concentration of the target aroma, and helps to build a stable and repeatable perception threshold evaluation system.

[0132] In this embodiment, the confidence interval corresponding to the opportunity level perception rate of the 30-person sample is calculated to serve as a baseline for comparison of whether it is "significantly higher than the opportunity level".

[0133] Premise assumption: sample size: n = 30, opportunity level perception rate: Confidence level: 95% (i.e. z = 1.96);

[0134] Wilson confidence interval calculation

[0135] The Wilson confidence interval formula is shown in formula (3) and (4):

[0136]

[0137] Substitute the parameters: n = 30, z = 1.96, z 2 = 3.8416;

[0138] Wilson confidence interval result n = 30)

[0139]

[0140] When the sample size is 30 and the opportunity level perception rate is 50%, the Wilson confidence interval is about [33.2%, 66.9%] (95% confidence level).

[0141] The confidence interval is used as a standard reference interval for comparison, indicating that the "perceived judgment rate" of a 30-person sample is expected to fall within 33.2% to 66.9% at a completely random or chance level. In this embodiment, if the actual perception rate is significantly higher than 66.9%, it can be considered that the perception result is significantly higher than the random level and has statistical significance.

[0142] (3) Determination of the lower limit of the postnasal aroma perception threshold: determine the actual perception rate P f In relation to the size of the upper limit of the above confidence interval, the actual perception rate in columns j = 3 to j = 7 as shown in Table 2 is greater than the upper limit of the confidence interval, and then the average value of the postnasal target aroma concentration of each column from j = 3 to j = 7 is calculated, as shown in Table 4, where the minimum value is 0.0359, i.e. this value is the lower limit of the postnasal perception threshold of orange flavor aroma.

[0143] Table 4 Actual perception rate and postnasal target aroma concentration data table

[0144]

[0145]

II

[0146] 1. Data collection

[0147] The upper limit of the postnasal target aroma concentration threshold is obtained, and the preconditions and data collection process are the same as those of the above

I

[0148] (1) Estimate the concentration range of orange flavor essence in the test material biscuit:

[0149] Estimate the concentration range of orange flavor essence in the test material biscuit: preliminarily preset the upper limit of the postnasal perception threshold of the target aroma according to the method of point (2) of the experimental procedure of this embodiment.

[0150] Using standard formula biscuits as matrix samples, without changing the proportion of other ingredients, different proportions of orange flavor essence were added to the biscuits to obtain samples with multiple gradient concentrations. Exponential increasing concentration design was initially used, i.e. the essence addition amount of each level sample was 5-10 times that of the previous level, in order to cover the potential upper limit of the postnasal perception threshold. In order to more accurately determine the upper limit of the postnasal perception threshold, the concentration of orange flavor essence in the test material was increased by 500-2000 based on M4, and the concentrations of each test material were designed within this interval, as shown in Table 5.

[0151] Through the organization of 30 trained sensory evaluators, each sample in the group was evaluated one by one, and the aroma perception evaluation was only through the posterior nasal pathway. After comprehensive evaluation, it was found that the sample in which most evaluators could stably perceive the orange flavor essence for the first time was N4, so the essence concentration corresponding to N4 was preliminarily set as the upper limit of the posterior nasal perception threshold of the target aroma.

[0152] Taking N4 as the center reference, continue to expand the essence concentration to both sides in equal ratio, and use a ratio gradient design to build samples with lower (N1-N3) and higher (N5-N7) concentrations, respectively, so as to obtain a total of 7 gradient concentration samples N1-N7, covering the concentration range from below the upper limit of the perception threshold to the saturated state of perception, in order to further accurately determine the upper limit of the posterior nasal perception threshold.

[0153] Table 5 Orange flavor essence addition concentration table (unit: μg / g biscuit)

[0154] N i )]]> Concentration of essence (μg / g) [N1] 1000 [N2] 2000 [N3] 4000 [N4] 8000 [N5] 16000 [N6] 32000 [N7] 64000

[0155] (2) Data collection for N1-N7:

[0156] According to the experimental procedure of this embodiment, each evaluator evaluated each N1-N7 test material once, and the data collection method was consistent with that for the lower limit of the posterior nasal aroma perception threshold.

[0157] (3) The perception intensity score recorded by each evaluator each time was paired with the corresponding posterior target aroma concentration value to form a data pair of target aroma concentration-perception intensity score. All evaluators evaluated each test material N i The target aroma concentration-perception intensity score data pairs perceived and detected constitute 7 data sets for the evaluation of N1-N7. The data set representation is shown in formula (2). The 7 data sets for the evaluation of N1-N7 are obtained, and the data lists for N1, N2, N3, N4, N5, N6 and N7 evaluated respectively are shown in Tables 6, 7, 8, 9, 10, 11 and 12.

[0158] Table 6 Target aroma concentration-perception intensity score data table obtained by all evaluators after evaluating N1

[0159]

[0160]

[0161] Table 7 Target aroma concentration-perception intensity score data table obtained by all evaluators after evaluating N2

[0162]

[0163]

[0164] Table 8 Target Odor Concentration-Perceived Intensity Score Data Table for N3 after Evaluation by All Panelists

[0165]

[0166] Table 9 Target Odor Concentration-Perceived Intensity Score Data Table for N4 after Evaluation by All Panelists

[0167]

[0168]

[0169] Table 10 Target Odor Concentration-Perceived Intensity Score Data Table for N5 after Evaluation by All Panelists

[0170]

[0171]

[0172] Table 11 Target Odor Concentration-Perceived Intensity Score Data Table for N6 after Evaluation by All Panelists

[0173]

[0174] Table 12 Target Odor Concentration-Perceived Intensity Score Data Table for N7 after Evaluation by All Panelists

[0175]

[0176] 2. Data Analysis

[0177] (1) For each panelist Pi, the perceived intensity scores Si corresponding to different post-nasal target odor concentrations Cj of the test materials (N1-N7) are extracted from the above Tables 6-12. ij (i = 1, 2,..., r; j = 1, 2,..., q), the odor concentration values and the corresponding perceived intensity scores are arranged in increasing order of concentration. The data set of the post-nasal target odor concentration-perceived intensity score relationship of panelist Pi is shown in Table 13. ij (i = 1, 2,..., r; j = 1, 2,..., q), the odor concentration values and the corresponding perceived intensity scores are arranged in increasing order of concentration. The data set of the post-nasal target odor concentration-perceived intensity score relationship of panelist Pi is shown in Table 13.

[0178] Table 13 Data Set of Post-Nasal Target Odor Concentration-Perceived Intensity Score Relationship of Panelist Pi

[0179]

[0180]

[0181] (2) Based on the individual postnasal target aroma concentration-perception intensity score relationship dataset of P1, the relationship between postnasal target aroma concentration (C) and perception intensity score (S) is fitted by Logistic curve. The fitted function is shown in Equation (5).

[0182]

[0183] Where S(C) is the perceived intensity score; L: the maximum score (here L = 10, because the highest perceived intensity score of P1 is 10); k: the slope of the curve (reflecting the rate at which the score increases with concentration); C0: the midpoint concentration (the concentration when the score reaches L / 2).

[0184] Fitting results: Through data fitting, the parameters L = 10, k = 0.85, C0 = 5.2063 were obtained, and the fitting function is:

[0185]

[0186] The fitting function above was used to plot the fitting graph of the retronasal aroma perception concentration-perception intensity score for evaluator P1, as shown below. Figure 4 As shown, the trend of the fitted curve is as follows:

[0187] At low concentrations (C < 5), the score increases rapidly with concentration;

[0188] At moderate concentrations (5 < C < 10), the score gradually approaches 10;

[0189] At high concentrations (C > 10), the scores tend to stabilize.

[0190] After fitting, the score increment and growth rate of perceived intensity are calculated. The growth rate is represented by the difference in score changes at adjacent concentrations of the fitting function, as shown in Equation (6).

[0191]

[0192] Threshold criteria: When the score increment of 3 consecutive data points is <0.3 or / and the growth rate is <5%, it is determined to enter the platform zone.

[0193] The calculation of the critical interval score increment and growth rate (high concentration range) is shown in Table 14:

[0194] Table 14: Calculation of score increment and growth rate for key intervals in the evaluation P1 retronasal target aroma concentration-perceived intensity scoring relationship data.

[0195] Concentration interval Score increment Growth rate 6.8060→13.5018 10.0→9.5 -0.07 13.5018→13.7736 9.5→10.0 1.84 13.7736→13.8412 10.0→10.0 0 13.8412→14.0382 10.0→9.5 -2.56 14.0382→14.0439 9.5→9.0 -87.72 14.0439→14.1982 9.0→9.5 3.23 14.1982→14.6196 9.5→10.0 1.19 14.6196→14.7377 10.0→10.0 0 14.7377→14.7573 10.0→10.0 0 14.7573→24.5018 10.0→10.0 0 ... ... ... 25.7377→40.7377 10.0→10.0 0

[0196] (3) From the concentration 14.6196, the score increment and growth rate of the subsequent data points (14.6196→14.7377→14.7573→24.5018→…→40.7377) are both 0.00, continuously satisfying <0.3 and <5%, therefore, the upper limit of the postnasal perception threshold of P1 is 14.6196.

[0197] (4) The upper limit of the postnasal perception threshold data of all evaluators is statistically processed, and the arithmetic mean is used to calculate the upper limit of the postnasal perception threshold.

[0198] According to the upper limit of the postnasal perception threshold calculation method of evaluator P1 (data sorting→Logistic fitting→score increment or / and growth rate analysis→platform zone identification→determination of the upper limit of the postnasal perception threshold), the upper limit of the postnasal perception threshold of evaluators P2-P30 is calculated one by one, and the upper limit of the postnasal perception threshold of evaluator P1 is added to obtain the results of the upper limit of the postnasal perception threshold of 30 evaluators respectively as shown in Table 15.

[0199] Table 15 Evaluators P1-P 30 Postnasal perception threshold upper limit determination result table

[0200]

[0201] Calculate the upper limit of the postnasal perception threshold: (14.6196+14.1341+138948+…+13.4788) / 30=13.8047

[0202] The arithmetic mean of the upper limit of the postnasal perception threshold of all evaluators in Table 15 is used to calculate the upper limit of the postnasal perception threshold of the group as 13.8047 ug / mL.

[0203]

Three

[0204] 1. The precise quantitative sampling of the postnasal perception concentration of aroma can be realized

[0205] The embodiment realizes the directional collection of aroma along the postnasal pathway during the release process after oral processing by designing a postnasal aroma collection device with clear structure and path separation. The device forms a closed sampling system independent of the anterior nasal pathway by setting a nasal catheter, a flow divider, a dryer and a multi-channel aroma capture structure, effectively eliminates the interference of the anterior nose, and ensures the specificity and stability of the collection path. In the experiment, 7 kinds of orange-flavored biscuit samples (M1-M7 or N1-N7) with exponentially increasing concentrations were used as test materials, 30 evaluators trained by standardizing postnasal perception scores conducted sensory tests, Tenax adsorption tubes were used to collect target aroma components in postnasal exhaled gas, and then gas chromatography-mass spectrometry (GC-MS) was used to quantitatively analyze volatile components in the samples, and a postnasal target aroma concentration and perception intensity score (C ij ,S ij ) paired data set was constructed.

[0206] The sampling device supports multi-stage continuous sampling and time period aroma capture, combined with point-by-point recording of evaluator perception data, forming a full-process aroma release-perception process quantitative trajectory, meeting the technical needs of postnasal path aroma quantitative research.

[0207] In summary, the device realizes dynamic and controllable quantitative determination of aroma in the postnasal perception area, provides high-quality data support for aroma threshold research and sensory response modeling, and significantly improves the scientificity and application value of postnasal perception aroma analysis.

[0208] 2. Scientifically obtain the lower and upper limits of the postnasal perception threshold of aroma

[0209] (1) Threshold lower limit determination:

[0210] The embodiment determines the perception rate P f significantly higher than the maximum value of the confidence interval of the opportunity level (50%). Taking the M2 sample as an example, its corresponding concentration level is stably perceived by most evaluators, and therefore can be regarded as the postnasal perception threshold lower limit of the target aroma.

[0211] (2) Threshold upper limit determination:

[0212] The relationship between the postnasal target aroma concentration and the perception intensity score is fitted by using the Logistic nonlinear model, the score increment or / and the continuous growth rate is analyzed, and the minimum concentration value at which the score enters the platform section is determined as the postnasal perception threshold upper limit of the evaluator. Finally, the upper limit values of all evaluators are statistically integrated (taking the average value) to obtain the group average threshold upper limit, which reflects the upper limit of postnasal aroma perception saturation and has practical significance for guiding the aroma dosage setting in product formulations.

[0213] Thus, the embodiment not only obtains the minimum perceptible concentration of aroma, but also clearly defines the upper limit concentration corresponding to the perception saturation value, providing quantifiable theoretical support for the dosage optimization and sensory intensity regulation of aroma use.

[0214] (3) Applicability and application prospect of the perception threshold determination method

[0215] The perception threshold determination method and quantitative device for post-nasal aroma constructed in the embodiment have good universality and are suitable for the following fields:

[0216] Food formula design: according to the perception lower limit and upper limit of the target aroma, combining the aroma release curve in the actual formula, a function model between the aroma addition concentration and the perception intensity is constructed, so as to deduce the optimal aroma substance addition ratio.

[0217] Flavor adjustment of oral life products: such as chewing gum, toothpaste, etc., by establishing a standardized model of aroma perception score, the consistency regulation and user experience optimization of product flavor are realized.

[0218] Flavor development and drug palatability design: based on the perception data, the perception response model of different populations is established, and clustering analysis or principal component analysis is used to support the development of personalized aroma addition strategy, and improve the adaptability and acceptance of products.

[0219] In addition, the method can also construct a standardized sensory evaluation database, realize the comparison of aroma scoring models of similar products for quality control and product iteration optimization; at the same time, it can be used as an aroma perception prediction tool to support the precision and data management of aroma use.

[0220] In summary, the embodiment realizes the high-precision, repeatable directional collection and concentration analysis of aroma in the post-nasal path by the self-designed quantitative device for post-nasal perception aroma concentration and the matching perception threshold determination method, establishes the perception threshold interval of the target aroma on the sensory level, and constructs the post-nasal target aroma concentration-perception intensity score function relationship model. The method can effectively guide the aroma formula optimization, the establishment of standardized evaluation system and the personalized flavor adjustment path design in different fields, has wide technical applicability and industrial promotion value, promotes the change of flavor-related products from experience deployment to data-driven development, and is a system solution with significant innovation and practicality in the field of flavor science and sensory technology.

[0221] The above embodiments should be understood as only for illustrating the present application and not for limiting the protection scope of the present application. After reading the content of the present application, those skilled in the art can make various modifications or modifications to the present application, and these equivalent changes and modifications also fall within the scope defined by the claims of the present application.

Claims

1. A device for the quantification of retronasal aroma concentration comprising a retronasal aroma collection device and a retronasal aroma analysis device; characterized in that, The said post-nasal aroma collection device comprises a nasal catheter (1), a dryer (2), a flow divider (3), an aroma capturing structure (4) and several air guide tubes (5); the said flow divider (3) comprises an air inlet tube (31), several air outlet tubes (32) and several valves respectively arranged on the air outlet tubes (32); the said aroma capturing structure (4) comprises a first one-way valve (41), an aroma capturing tube (42) and a waste gas collection bag (43), the inlet of the first one-way valve (41) is connected with the air outlet tube (32) of the flow divider (3) through the air guide tube (5), the outlet of the first one-way valve (41) is connected with the air inlet of the aroma capturing tube (42) through the air guide tube (5), and the air outlet of the aroma capturing tube (42) is connected with the waste gas collection bag (43); the said nasal catheter (1) comprises nasal insertion segments (11) respectively inserted into two nostrils, the two nasal insertion segments (11) are connected with one end of the dryer (2) through the air guide tube (5), the other end of the dryer (2) is connected with the air inlet end of the flow divider (3) through the air guide tube (5), and the several air outlet ends of the flow divider (3) are respectively connected with the inlets of the several first one-way valves (41); The measured material is placed in the mouth, the lips and the nasal breathing passage are closed, the measured material is processed through the oral cavity, the measured gas is formed in the oral cavity and the pharyngeal cavity, the valve on one of the air outlet tubes (32) of the flow divider (3) is opened, then the measured gas is exhaled through the post-nasal path and the nasal insertion segments (11), the measured gas enters one of the aroma capturing structures (4) through the dryer (2) and the flow divider (3) in sequence, the target aroma in the measured gas is adsorbed by the aroma capturing tube (42), and the remaining gas is discharged into the waste gas collection bag (43), so that one gas collection is completed; the process is continued for several times, the valves on the different air outlet tubes (32) of the flow divider (3) are controlled, and the gas in different processes is continuously collected in sequence through the several aroma capturing structures (4).

2. The apparatus for quantifying the concentration of a retronasal aroma according to claim 1, wherein The flexible positioning sheet (6) and the pull rope (7) limiting the flexible positioning sheet (6) are further included, the nasal catheter (1) further comprises a transverse segment (12) arranged transversely, the transverse segment (12) is fixed on the flexible positioning sheet (6), and the flexible positioning sheet (6) and the transverse segment (12) are limited in the philtrum by the pull rope (7).

3. The apparatus for quantifying the concentration of a retronasal aroma according to claim 1, wherein The flow divider (3) further comprises a controller (34), and the valves are all electromagnetic valves (33) controlled by the controller (34).

4. The apparatus for quantifying the concentration of a retronasal aroma according to claim 1, wherein The air tube clamp (8) is further included and arranged on the air guide tube (5) between the nasal insertion segment (11) and the dryer (2), so as to control the on-off of the air guide tube (5).

5. The apparatus for quantifying the concentration of a retronasal aroma according to claim 1, wherein A second one-way valve (9) for breathing air supplement is further arranged on the pipeline between the nasal insertion segment (11) and the dryer (2).

6. The apparatus for quantifying the concentration of a retronasal aroma according to claim 1, wherein Nose plugs (13) for sealing the nostrils are respectively arranged on the outer walls of the two nasal insertion segments (11).

7. A method for the determination of the perception threshold of the concentration of a retronasal aroma, characterized by, The method comprises the following steps: S1, preparing several portions of the material M to be tested containing a step concentration of the target aroma substance i (i = 1, 2,..., r); S2, obtaining the lower limit of the post-nasal perception threshold St1, several panelists P e (e = 1, 2, …, k) respectively for several materials M i processing and evaluation; wherein each panelist processes and realizes gas capture according to the number of aroma capture structures in the device according to any one of claims 1-6 for each material to be tested; the post-nasal gas generated during the capture process is sequentially passed through the aroma capture tube for the adsorption of target aroma, while the residual gas is introduced into the waste gas collection bag; St2, after each evaluator completes each aroma trapping step for each test material, the mass value of the target aroma adsorbed in the aroma trapping tube is measured as m ij (i = 1, 2, …, r; j = 1, 2, …, q), and the gas volume V in the corresponding exhaust gas collection bag is measured ij (i = 1, 2, …, r; j = 1, 2, …, q), thereby calculating the concentration value C of the retronasal aroma in each step ij (i = 1, 2, …, r; j = 1, 2, …, q); at the same time, whether the evaluator can perceive the target aroma at each aroma concentration is recorded, and the perception result is judged as "yes / no", and the number of "yes" judgments X and the number of "no" judgments Y of all evaluators for the aroma perception in the same grade aroma trapping step of the same test material are counted; St3, on the basis of a certain confidence, according to the confidence interval calculation formula, it is concluded that the upper limit P of the confidence interval of the same level of the same material by a number of evaluators in the same step of aroma capture is significantly higher than the opportunity level s ; wherein the opportunity level is defined as the expected probability benchmark of the "yes / no" judgment of the perception result under random conditions, i.e. 50%; P is the actual perception rate of the same material by several evaluators in the actual operation process f (f = 1, 2, …, r x q), wherein the actual perception rate calculation formula is as (1), and the actual perception rate P f is compared with the upper limit P s of the confidence interval, all P s greater than the upper limit P f of the confidence interval are counted, and the average value of all the post-nasal target aroma concentrations corresponding to each P f is calculated The minimum value is the lower limit of the post-nasal perception threshold of the target aroma. P f = X / (X + Y) (1) S3, obtaining the upper limit of the post-nasal perception threshold Stp1, for each evaluator, obtain the perceived intensity scores S corresponding to the plurality of different post-nasal target aroma concentrations ij (i = 1, 2,..., r; j = 1, 2,..., q), arrange the aroma concentration values and the corresponding perceived intensity scores in increasing order of concentration, to form a data set of the individual post-nasal target aroma concentration-perceived intensity score relationship for each evaluator; Stp2, based on the individual postnasal target aroma concentration-perceived intensity score data set of each evaluator, a non-linear function is used to fit the relationship between postnasal target aroma concentration and perceived intensity score, the non-linear function is Logistic curve, Sigmoid function or other concentration-response relationship model; after fitting, the growth rate of the perceived intensity score is calculated, the growth rate can be expressed by the derivative of the fitting function or the difference value of the score change at adjacent concentrations; Stp3, when the score growth rate is less than the set threshold, the score platform section is identified, the preset threshold is defined as the continuous score increment less than 0.3 or / and the continuous growth rate less than 5%; the minimum aroma concentration value corresponding to the entry into the platform section is determined as the upper limit of the postnasal perception threshold of the evaluator; Stp4, the postnasal perception threshold upper limit data of all evaluators is statistically processed, and the postnasal perception threshold upper limit can be calculated by using arithmetic mean, median or truncated mean after removing extreme values.

8. The perceptual threshold determination method of claim 7, wherein, The method further comprises the step of obtaining the postnasal target aroma concentration-perceived intensity score data set based on the perceived intensity score, which comprises: Step1, postnasal aroma perception score training is performed on a plurality of evaluators participating in sensory evaluation, only the aroma intensity is perceived through the postnasal path, so that the evaluators understand the definition and reference standard of the score scale, that is: 0 represents complete inability to perceive, the maximum value of the pre-set score scale represents reaching the maximum acceptable perception intensity, the scores between 0 and the maximum value are linearly related to the postnasal aroma perception intensity; and typical samples are provided to establish a reference for scoring; evaluators with abnormal perception scores are removed; Step2, after the training, the evaluators successively evaluate a plurality of gradient concentrations of the test materials, j times of continuous scoring are performed for each evaluation of the test material, and a certain time interval is maintained between each two sample evaluations to eliminate the adaptation effect; Step3, after completing each evaluation, each evaluator selects a corresponding score on the pre-set score scale according to the subjective intensity perception of the target aroma and records it; Step4, the perceived intensity score value recorded by each evaluator and the corresponding postnasal target aroma concentration value are collected to form a postnasal target aroma concentration-perceived intensity score pairing data set as formula (2) for subsequent fitting of the postnasal target aroma concentration-perceived intensity score relationship curve; wherein C ij represents the aroma concentration of the ith material in the jth aroma release process, S ij is the corresponding perceived intensity score; Step5, when continuous scores are abnormal during the scoring process, the relevant data is reviewed or removed to improve the consistency and reliability of the scores.

9. The use of the quantification device according to any one of claims 1-6 in the field of, but not limited to, food formula design, in-mouth living product flavoring, spice development or drug taste evaluation.

10. Use of the sensory threshold determination method according to any one of claims 7 to 8 in the field of, but not limited to, food formulation design, in-mouth consumer product flavouring, flavour development or pharmaceutical taste evaluation, characterized in that, Comprising the following steps: Ste1, on the basis of obtaining the lower limit and upper limit of the postnasal perception threshold of the target aroma, a functional relationship model between the actual perceived target aroma concentration and the perceived intensity score is established; Ste2, according to the sensory preference of different groups, the intensity score and its variability, the clustering analysis, principal component analysis or other statistical modeling methods are applied to the perception data for grouping and classification, and a diversity perception response model is constructed; Ste3, based on the above threshold interval and the perception model of the population, combined with the release characteristics of the aroma components in the specific material matrix of each formula or product system, the optimal addition ratio interval of the target aroma substance in the formula is deduced, so that the released postnasal target aroma concentration in the product use or intake process is stable within the perception threshold range, ensuring that the product has the ideal postnasal aroma perception intensity; Ste4, according to the above optimization ratio results, a formula design reference range and standardized sensory evaluation model of the target aroma is established, which is used as the basis for product formula optimization and quality control, such as food, spices or drugs, to realize precise control of postnasal aroma flavor and improve individualized sensory experience.

Images