Method for removing peculiar smell of meat product based on flavor molecular structure

Abstract

The invention discloses a method for removing peculiar smell of meat products based on a flavor molecular structure, which utilizes an aroma active compound to occupy a binding site of a peculiar smell compound on myofibrillar protein so as to release the peculiar smell compound and remove peculiar smell. The principle that the spices can remove the peculiar smell is accurately disclosed by utilizing a modern molecular sensory science technology and a multispectral technology and combining molecular dynamics simulation, and the peculiar smell removal of meat products is guided on the basis of the principle, so that the aim of improving the accuracy and the efficiency of controlling the industrial processing flavor of meat dishes is fulfilled.

Description

Technical Field

[0001] The present invention relates to the technical field of meat product processing, and more specifically, to a method for removing foreign smell from meat products based on flavor molecular structure. Background Art

[0002] Flavor is an important sensory indicator for evaluating meat products. It directly affects consumers' sensory experience and psychology, and is also an important reference indicator for consumers to evaluate the quality of meat products. With the improvement of the quality of life, people's requirements for meat flavor are getting higher and higher. There are many kinds of smells and tastes (referred to as "flavors") in food, some of which are more common, while some flavors are unique. However, some special smells or tastes may make our mouths, noses, tongues and other organs feel uncomfortable, resulting in a feeling of boredom. This kind of taste that most people cannot accept is generally called "peculiar smell". The presence of peculiar smell substances in meat products will directly reduce the taste, edible value and market competitiveness of the food. Therefore, it is an urgent problem to develop a method for removing peculiar smell from meat products, so that livestock and poultry meat products can be further developed, and consumers can better experience delicious food and obtain products with better flavor. Summary of the invention

[0003] The purpose of the present invention is to provide a method for removing the odor of meat products based on the flavor molecular structure, which can effectively and accurately guide the removal of the odor in meat dishes, so as to improve the accuracy and efficiency of the flavor control in the industrial processing of meat dishes.

[0004] In order to achieve these purposes and other advantages according to the present invention, a method for removing odor from meat products based on flavor molecular structure is provided, in which aroma-active compounds are used to occupy the binding sites of odor compounds on myofibrillar proteins, thereby releasing the odor compounds and removing the odor.

[0005] Preferably, the odor compounds include: hexanal, nonanal, benzaldehyde, 1-pentanol, 1-octen-3-ol

[0006] Preferably, the off-flavor compound is hexanal.

[0007] Preferably, the binding sites of the odorous compound on the myofibrillar protein include:

[0008] A2-R18-E89-D90-Y118-R148-Q149E150-P152-A151,

[0009] T335-D336-K349-Y353L300-I292-P298-K297-L332-Q291,

[0010] V589-I470-N474-D472-K575-A576-A578-N592-D590.

[0011] Preferably, the aroma active compounds include: geraniol, D-limonene, acetophenone.

[0012] Preferably, the method of using aroma-active compounds to occupy the binding sites of odor compounds on myofibrillar proteins comprises: using spices containing aroma-active compounds to treat meat products having odor compound binding sites on myofibrillar proteins.

[0013] Preferably, the method of treating meat products with spices is: pickling.

[0014] The invention also provides a meat product, which is processed by the method.

[0015] The present invention includes at least the following beneficial effects: the present invention utilizes modern molecular sensory science and technology and multi-spectral technology, combined with molecular dynamics simulation, to accurately reveal the principle that spices can remove odors. Based on this principle, the odor removal of meat products is guided, thereby achieving the purpose of improving the accuracy and efficiency of flavor control in the industrial processing of meat dishes.

[0016] Other advantages, objectives and features of the present invention will be embodied in part through the following description, and in part will be understood by those skilled in the art through study and practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 Radar chart of sensory evaluation scores for grilled chicken before and after marinating with basil leaves;

[0018] Figure 2 The bar graph shows the effect of adding different aroma active compounds on the binding of odor compounds to myofibrillar protein;

[0019] Figure 3 It is a bar graph of BPB binding amount and total thiol binding amount of myofibrillar protein treated with different aroma active compounds;

[0020] Figure 4 The zeta potential and particle size bar graphs of myofibrillar proteins treated with different aroma active compounds;

[0021] Figure 5 are scanning electron microscopy images of myofibrillar proteins treated with different aroma-active compounds;

[0022] Figure 6 Atomic force microscopy images of myofibrillar proteins treated with different aroma-active compounds;

[0023] Fig. 7AFourier infrared spectroscopic images of myofibrillar proteins treated with different aroma active compounds;

[0024] Figure 7B The secondary structure content images of myofibrillar proteins treated with different aroma-active compounds;

[0025] Fig. 8A The fluorescence quenching spectra of myofibrillar protein obtained in the presence of different concentrations of D-limonene;

[0026] Figure 8B The fluorescence quenching spectra of myofibrillar protein obtained in the presence of different concentrations of geraniol;

[0027] Figure 8C The fluorescence quenching spectra of myofibrillar protein obtained in the presence of different concentrations of acetophenone;

[0028] Fig.8D The Stern-Volmer equation fitting curves of D-limonene at 298K, 308K and 318K respectively;

[0029] Fig. 8E The Stern-Volmer equation fitting curves of geraniol at 298K, 308K and 318K respectively;

[0030] Figure 8F The Stern-Volmer equation fitting curves of acetophenone at 298K, 308K and 318K respectively;

[0031] Fig. 9 It is a bar graph of the headspace odor compound content of myofibrillar protein treated with different aroma active compounds;

[0032] Fig.10 Schematic diagram of the secondary structure changes of myosin treated with different aroma-active compounds in MD simulation;

[0033] Fig.11 Schematic diagram of the complexes of different aroma-active compounds with hexanal and myosin in MD simulation;

[0034] Fig.12 Schematic diagram of the interaction between different aroma active compounds and hexanal and myosin in MD simulation, wherein Figures A, D, and G are schematic diagrams of the interaction between geraniol-hexanal-myosin; Figures B, E, and H are schematic diagrams of the interaction between D-limonene-hexanal-myosin; Figures C, F, and I are schematic diagrams of the interaction between acetophenone-hexanal-myosin;

[0035] Fig.13Schematic diagrams of the mechanisms of different aroma-active compounds removing odorous compounds, wherein A is a schematic diagram of the mechanism of geraniol removing the odorous compound hexanal on myosin; B is a schematic diagram of the mechanism of D-limonene removing the odorous compound hexanal on myosin; C is a schematic diagram of the mechanism of acetophenone removing the odorous compound hexanal on myosin. DETAILED DESCRIPTION

[0036] The present invention is further described in detail below in conjunction with the accompanying drawings so that those skilled in the art can implement the invention with reference to the description.

[0037] It should be noted that the experimental methods described in the following embodiments are conventional methods unless otherwise specified, and the reagents and materials can be obtained from commercial channels unless otherwise specified.

[0038] <Test method>

[0039] Chicken was taken and divided into two equal weight portions, one portion was marinated with perilla leaves (MG group), and the other portion was used as a blank control (NMG group). Both portions of chicken were roasted under the same conditions.

[0040] <Sensory Evaluation>

[0041] The evaluation was conducted under white light at a fixed temperature of 26 ± 2 °C. The sensory panel had a total of 24 evaluators (12 men and 12 women; all of whom had been engaged in flavor-related research for more than 3 years) from the Meat Dishes Processing Technology Integration Laboratory of the Ministry of Agriculture and Rural Affairs. Before the test, the panelists were asked to be physically and mentally aroused for at least 3 hours before the test. The evaluation was divided into 3 steps:

[0042] Step 1: 2g of MG and NMG were weighed and placed in a sensory olfactory bottle, and the panelists were left to discuss and confirm the off-flavor descriptor labels. The odor descriptors included: meaty, caramel, herbal, greasy, stable, and chicken.

[0043] Step 2: Provide food references to the panelists to reach a consensus on the meaning and intensity of each descriptor. The food references were prepared as follows: Meaty (cooked chicken, size: 1×1×0.5 cm 3 , intensity 3.0), caramel (caramel popcorn, weight: 2g, intensity 3.0), herbal (mint, weight: 2g, intensity 2.5), grease (chicken fat, weight: 2g, intensity 2.5), stable smell (leather, weight: 2g, intensity 2.5), chicken smell (raw chicken, weight: 2g, intensity 2.5).

[0044] Step 3: All panelists scored the intensity of the odor descriptive labels and evaluated each label on a scale of 0-3 points in increments of 0.5 points. Both sets of samples were sealed in triplicate in 20 ml sniffing bottles to prevent odor from escaping. Each sample was evaluated using a randomized complete block design. The aroma assessors were blind to the identity of the sample to be tested, and each panelist evaluated each sample three times. The final score for each sample was determined by averaging the three individual evaluations.

[0045] The sensory evaluation results are as follows Figure 1 As shown. Figure 1 It can be seen that the aroma spectrum of roasted chicken changed significantly before and after perilla leaves were pickled. After perilla leaves were pickled, the fishy smell dropped from 2 points to 1 point, and the stable smell also dropped significantly. At the same time, the unique herbal smell of perilla leaves increased the overall herbal smell of the sample, and perilla leaves pickled increased the meaty taste score.

[0046] <Mechanism Analysis>

[0047] 1) Sample preparation:

[0048] ① Myofibrillar protein (MPs) extraction: Chicken breast was minced and mixed with 4% (w / v) phosphate extract (0.1mol / L NaCl, 2mmol / L MgCl2, 1mmol / l EgTA, 10mmol / l K2HPO4, pH 7.0). Repeat homogenization at 15000rpm for 30s, followed by centrifugation for 15min (2000g, 4°C). The supernatant was discarded to collect the precipitate. The phosphate extract was added to the precipitate and centrifuged 3 times. Subsequently, the precipitate was washed 3 times with 4% (w / v) of 0.1mol / l NaCl. Before the final centrifugation, the fine connecting tissue was removed by filtering with gauze and the pH was adjusted to 6.0 with 0.1mol / L HCl. The precipitate after centrifugation was MPs. BCA protein assay kit (Thermo Fisher Scientific Inc., Waltham, USA) was used to determine the protein concentration.

[0049] ② Preparation of mixtures of characteristic aroma active compounds (CAACs) of perilla leaves and MPs: 1 mg / mL solutions of different aroma active compounds (including geraniol, D-limonene and acetophenone) were prepared in methanol. Afterwards, the different aroma active compound solutions were mixed with 2 mg / mL MPs solutions to produce different CAACs-MPs mixtures with a concentration of 10 mg / g.

[0050] 2) Chemical analysis:

[0051] The present invention uses multi-spectral combined with protein microstructure changes to accurately identify the interaction between CAACs and OFCs, specifically including:

[0052] ①GC-MS was used to find that after adding CAACs, the content of OFCs changed. The results are as follows: Figure 2 As shown;

[0053] After the three CAACs were added, the number of OFCs changed significantly, which may be because CAACs changed the structure of MPs and affected the binding ability of MPs to OFCs. The interaction between protein and flavor compounds was replaced by the interaction between protein and protein, resulting in the weakening of the binding between protein and OFCs, and finally the OFCs were released into the air. On the other hand, this may be due to the interaction between CAACs and OFCs. It is worth noting that different CAACs have different abilities to release OFCs, which may be related to their own properties and protein conformational changes. Among them, acetophenone has the lowest OFCs release, which may be due to the location of the ketone group inside the molecule. This produces a stronger steric effect, hindering the binding of the ketone group to the protein, and a small amount of OFCs is squeezed out. After geraniol was added to MPs, the relative release rate of hexanal in OFCs was the highest, indicating that geraniol has a strong release ability for this compound. In addition, geraniol may compete with hexanal for binding sites on MPs, destroying the interaction between hexanal and MPs, and ultimately leading to the release of hexanal;

[0054] ② The changes in protein surface hydrophobicity, total thiol groups, particle size and Zeta potential after adding CAACs were observed using a fluorescence spectrophotometer. Figure 3 , 4 As shown;

[0055] A. Surface hydrophobicity

[0056] The effect of CAACs on the structure of MPs was studied in detail to see whether CAACs affect the interaction between OFCs and proteins by changing the protein structure, ultimately leading to the release of OFCs. Surface hydrophobicity can reflect the changes in the physical and chemical state of the surface of protein molecules. After adding CAACs to MPs, the surface hydrophobicity of MPs was significantly reduced ( Figure 3 ).

[0057] This may be due to excessive swelling of MPs after the addition of CAACs, which leads to MPs aggregation. In addition, this may also be attributed to the binding of CAACs to the hydrophobic regions of proteins through hydrophobic interactions. Previous studies have found that the addition of flavor compounds can reduce the content of hydrophobic groups on the surface of MPs and prevent hydrophobic amino acids from being exposed on the surface of MPs, allowing them to be re-embedded. Therefore, the amount of BPB binding is reduced, which is consistent with our results. Figure 3It can be seen that the amount of BPB bound to different compounds is different, and there are even significant differences. This may be due to the different active groups of each compound, resulting in different binding abilities.

[0058] B. Total thiol content

[0059] By measuring the total thiol content, we can explain the redox state of the thiol, the functional changes of the protein, and the antioxidant capacity of the system. After adding D-limonene and geraniol to the protein, the total thiol content did not change significantly ( Figure 3 ). D-limonene is a cyclic monoterpenoid containing a carbon-carbon double bond, but its chemical properties are relatively stable. At room temperature, it does not react with sulfhydryl groups as easily as some strong oxidants or reducing agents. Therefore, D-limonene does not usually react directly with sulfhydryl groups, nor does it significantly reduce or increase the content of sulfhydryl groups. At the same time, D-limonene can act as an antioxidant to protect sulfhydryl groups from oxidative stress, thereby maintaining the total sulfhydryl content in proteins or other sulfhydryl-containing molecules.

[0060] However, geraniol can capture oxygen free radicals or other oxidants to prevent them from reacting with sulfhydryl groups. Therefore, geraniol can delay the oxidation process of free sulfhydryl groups, thereby protecting sulfhydryl groups and preventing them from converting into disulfide bonds or other oxidation products. After adding acetophenone to protein, the total sulfhydryl content was significantly reduced. This may be because acetophenone reacts with sulfhydryl groups through nucleophilic addition, directly reducing the number of free sulfhydryl groups in the total sulfhydryl content.

[0061] C. Particle size and zeta potential analysis

[0062] The zeta potential of proteins can be used to characterize the surface charge and electrostatic interaction of MPs after adsorption onto CAACs. Figure 4 It can be observed that there is no significant change in zeta potential after the addition of D-limonene, which may be due to its own structure. D-limonene does not carry positive or negative charge, so it does not directly interact significantly with charged amino acid residues on the protein surface (such as negatively charged glutamic acid or positively charged lysine).

[0063] After adding geraniol, the absolute value of the zeta potential of MPs increased. The hydroxyl groups of geraniol may change the charge distribution of amino acids on the surface of MPs by forming hydrogen bonds or weak interactions, thereby affecting the zeta potential of MPs. The results of adding acetophenone and geraniol were similar, but the zeta potential value of geraniol decreased more significantly. This may be because the keto group of acetophenone can react with nucleophilic groups (such as amino or thiol) on the surface of proteins, changing the charge distribution on the surface of proteins and thus affecting the zeta potential.

[0064] like Figure 4As shown in the figure, after adding CAACs, the average particle size of MPs increased significantly, indicating that the addition of CAACs caused the aggregation of MPs. It can also be observed that different CAACs lead to different degrees of MPs aggregation, which may be related to the structure of the flavor compounds themselves. Different CAACs have different hydrophobic interactions with proteins, which changes the exposure of the hydrophobic area on the protein surface, which should be the main reason for the inconsistent particle size distribution.

[0065] ③ Scanning electron microscopy (SEM) and atomic force microscopy (AFM) were used to observe the changes in the protein microstructure after the addition of CAACs. Figure 5 , 6 As shown;

[0066] from Figure 5 It can be seen that the microstructure of the untreated MPs looks smooth and evenly distributed. The microstructure of the sample treated with CAACs is different from that of the control group. After adding CAACs, the protein becomes viscous and obvious aggregation occurs on the surface.

[0067] from Figure 6 It can be seen that after adding CAACs, the surface particle size of the test group increased significantly compared with the control group. The untreated protein was only 4nm in size. After adding D-limonene, although the height did not change, it can be seen that the protein has aggregated. The protein with the addition of geraniol has the highest aggregation degree, reaching 20nm. Previous studies have found that the interaction between flavor compounds and MPs molecules may reduce the steric hindrance between MPs molecules, ultimately leading to an increase in the tendency of MPs to self-aggregate. With the help of FT-IR and fluorescence spectroscopy, the interaction between the three CAACs and proteins was further analyzed from the perspective of molecular configuration.

[0068] ④ Fourier transform infrared (FT-IR) spectroscopy was used to study whether the secondary structure of the protein changed after adding CAACs. Fig. 7A , 7B As shown;

[0069] FT-IR is often used to detect the interaction between molecules and proteins. CAACs-MPs and MPs have similar FT-IR spectra ( Fig. 7A ), indicating that no new covalent bonds were formed after the addition of CAACs. This means that the interaction between CAACs and MPs mainly occurs through non-covalent interactions.

[0070] The α-helical structure is mainly stabilized by intermolecular hydrogen bonds between C=O and NH groups. After adding CAACs, the content of α-helical structure decreased to varying degrees, while the content of random coil structure increased ( Figure 7B). The content of α-helical structure decreased to a greater extent compared with acetophenone and D-limonene. These compounds bind to amino acid residues in the polypeptide chain of MPs, disrupting their hydrogen bonding network and destroying intramolecular hydrogen bonds, thereby changing the protein structure. The reduction in the length of α-helical structure observed after the addition of geraniol may be attributed to its ability to form hydrogen bonds with oxygen and nitrogen atoms on the protein backbone. Considering the changes in secondary structure after complexation of flavor compounds with proteins, there seems to be a clear interaction between CAACs and MPs.

[0071] ⑤ Fluorescence spectroscopy was used to determine the interaction between protein and CAACs after the addition of CAACs, and the results are shown in Figure 8;

[0072] Fluorescence quenching of proteins is an effective method to study the changes in the tertiary structure of proteins after the addition of CAACs. We added D-limonene at concentrations of 0, 0.3625, 0.725, 1.25, 2.5, and 5 mM to a 2 mg / mL MPs solution and detected the fluorescence intensity of the MPs solution. The same was true for geraniol and acetophenone.

[0073] Test results such as Figures 8A to 8C As shown, the fluorescence intensity decreased with increasing concentrations of CAACs, indicating that the tertiary structure of MPs changed significantly. This change may be due to protein unfolding and the interaction between flavor compounds and fluorophore-containing residues.

[0074] To further explore the type of fluorescence quenching between CAACs and MPs, we used the Stern-Volmer equation to analyze the quenching data (e.g. Figures 8D to 8F The obtained K q The value is much higher than the maximum dynamic quenching rate constant (2.0×1010L·mol-1), indicating that the fluorescence quenching mechanism is static quenching. This static quenching occurs due to molecular binding to form a complex, rather than dynamic quenching due to molecular diffusion and collision. CAACs contain hydroxyl groups and carbon-carbon double bonds, which are more likely to bind to proteins than the carbon-carbon double bonds in geraniol and the ketone groups in acetophenone. In addition, tryptophan, tyrosine, and phenylalanine residues tend to bind to molecules with insufficient charge because the π electron clouds in their binding cavities form electron transfer complexes). Hydrophobic interactions are the main forces driving the formation of D-limonene-MPs, geraniol-MPs, and acetophenone-MPs complexes (ΔH>0 and ΔS>0). In addition, the interaction between CAACs and MPs is spontaneous (ΔG<0).

[0075] ⑥GC-MS was used to analyze whether there was interaction between OFCs and CAACs that affected odor removal. The results were as follows: Fig. 9 As shown;

[0076] The previous article analyzed the interaction between CAACs and MPs and found that there was an interaction between CAACs and MPs. The reason why OFCs were eventually eliminated may be that after the addition of CAACs, the protein structure changed, the OFCs that were originally bound to the protein were squeezed out, and the interaction bonding sites between OFCs and proteins were replaced by protein-protein interactions. CAACs have a stronger binding ability than OFCs, and CAACs eventually replaced OFCs to bind to the protein structure, and CAACs were released into the headspace.

[0077] In addition to the interaction forces between MPs and CAACs, there may also be interaction forces between CAACs and OFCs. The interaction forces between odor molecules lead to mutual pulling and dragging, which may lead to odor removal. In order to verify whether there are additional forces between odor molecules that affect odor removal, we further conducted odor molecule interaction force experiments. We added three CAACs to different OFCs and collected the peaks of OFCs by headspace gas chromatography. After statistics, the headspace peak areas of different OFCs were obtained. The results are shown in the figure. Fig. 9 shown.

[0078] from Fig. 9 It can be seen that when the three CAACs were added to different OFCs, the difference in headspace peak area was not significant, indicating that the interaction between odor molecules had no significant effect on odor release. This indicates that the interaction between CAACs and OFCs is not the cause of the increase in headspace odor compounds. The interaction between CAACs and MPs is the main reason for affecting OFCs release.

[0079] 3) Molecular dynamics simulation:

[0080] Molecular dynamics simulations observed that in addition to the interaction between CAACs and MPs affecting odor removal, whether there is a binding site crowding effect between OFCs and CAACs that affects odor removal. The specific contents include:

[0081] ① The number of compounds bound to the protein was uniformly set to 40. First, 40 hexanal molecules were randomly deployed around the protein, and the protein system was subjected to MD simulation at 26 °C for 180 ns, and then the simulation was terminated. The structure of the myosin-hexanal molecular complex at the 180 ns time node was extracted for subsequent binding mode analysis. Then, three different CAACs (each flavor represented by 40 molecules) were randomly placed around the myosin-hexanal molecular complex structure, and the composite system was constructed. Random competition initial structure construction was performed in two stages. In the first stage, after adding a restraining force of -1500 kcal / mol to all heavy atoms on the protein, the structures of the myosin-hexanal-geraniol, myosin-hexanal-D-limonene, and myosin-hexanal-acetophenone compounds were extracted corresponding to the 150 ns state to check the competitive binding state, and then the second stage MD simulation was performed. After removing the restraining force, the overall average structure of the molecules in the 180 ns state was extracted for subsequent bonding mode and differential analysis.

[0082] ②MD simulations were performed using the MD software GROMACS2021.5. The MD simulation time was uniformly limited to 180ns. The entire protein system used the Amber FF99SB force field, and the small molecule force field parameters were generated using CGENFF. After the system was built, conventional MD simulations were performed using GROMACS2021.5. During the simulation, the system was first minimized, and after 500PS equilibrium under the isothermal ensemble (NVT), a long-term production phase kinetic simulation was performed under the NPT ensemble. The simulation results were visualized using the Gromacs software embedded program and Visual MD (VMD). Use the software's integrated tools to calculate data such as root mean square deviation (RMSD) and root square fluctuation (RMSF).

[0083] The results of protein denaturation after adding CAACs were verified by MD simulation. The results showed that ( Fig.10 ), the secondary structure of the protein changed significantly after binding to CAACs. The main manifestation was a decrease in α-helical structure and an increase in random helical structure, indicating that the protein structure changed from an ordered structure to a disordered structure. After adding CAACs, the content of β-folded structure also increased, indicating that MPs aggregated at this time. These research results are consistent with the results of FT-IR experiments.

[0084] MD simulation was performed to explore the mechanism of odor removal by CAACs. The interactions among proteins, OFCs, and CAACs were further investigated from a molecular perspective. Hexanal, as a representative odor compound, is often reported in meat products. Hexanal has a grassy smell, and when its content is high, it will mask or affect the fresh flavor of the chicken itself. In the binding experiment, the release amount of hexanal was the highest.

[0085] Therefore, we chose hexanal as a representative compound of OFCs for MD simulation. After adding 40 hexanal molecules to myosin and simulating for 60ns at 26°C, the structure of myosin tended to be stable. All 40 hexanal molecules bind to myosin, and they are evenly distributed on the surface of myosin and in the tiny cavities inside. Subsequently, we constructed a simulation system of myosin-hexanal and three CAACs to explore how the interaction between CAACs molecules and proteins can achieve the removal of OFCs. The entire simulation process was carried out in two stages. The first stage analyzed the competitive binding state of CAACs and OFCs with myosin during the simulation. As time increased, CAACs molecules gradually began to contact myosin and eventually stably bound to the myosin surface. When participating in the competitive binding of CAACs, acetophenone competed weakly, D-limonene competed strongly, and geraniol competed the strongest. The second stage analyzed the structural morphology of CAACs and myosin. The changes in the binding modes of the two were studied, and the binding mode analysis was performed ( Fig.11 ).

[0086] The molecular energy of the three constructed single systems binding to myosin was calculated using the MMBSA energy calculation module of the AMBER software. The compound with the highest odor removal efficiency was geraniol, whose average binding energy with protein was -7.69644 kcal / mol. Finally, 35 of the 40 hexanal substances were directly squeezed out by geraniol and could not bind to proteins. The average binding energy of the remaining 5 hexanal substances with protein was -4.67025 kcal / mol. The above results show that the binding energy between geraniol and protein is stronger, so hexanal molecules can be easily squeezed out. Geraniol, which has the most intense competition, has the highest odor removal efficiency, which is consistent with the results of the headspace experiment. Compared with geraniol, D-limonene has a slightly lower odor removal efficiency. Among the 40 D-limonene molecules, 37 D-limonene molecules can bind to the protein surface, and the corresponding average binding energy is -5.86735 kcal / mol. However, it is worth noting that only 25 D-limonene molecules occupy the binding sites of the original hexanal molecules, so there are still 12 hexanal molecules that have not been squeezed out and can still bind to proteins, and the corresponding average binding energy is -4.70760 kcal / mol. Therefore, D-limonene is less efficient in removing odors. The lowest deodorizing efficiency is acetophenone. Acetophenone molecules have the weakest effect in squeezing out hexanal molecules, and only 34 acetophenone molecules bind to proteins, of which 25 hexanal molecules are still bound to proteins and are not squeezed out. The average binding energy of acetophenone is -5.36392 kcal / mol, but it is still higher than that of hexanal molecules, so acetophenone has the lowest efficiency. This may be due to the air steric hindrance effect of the ketone group, which limits the binding of the ketone group to proteins.

[0087] Fig.12 The interaction between CAACs-OFCs-MPs molecules is shown. The binding sites of geraniol and hexanal are consistent, namely A2-R18-E89-D90-Y118-R148-Q149E150-P152-A151. The positions of geraniol and hexanal overlap, so that geraniol can squeeze hexanal out of the original binding site and rebind with the protein at the same binding site. The binding sites of D-limonene and acetophenone with hexanal molecules are T335-D336-K349-Y353L300-I292-P298-K297-L332-Q291 and V589-I470-N474-D472-K575-A576-A578-N592-D590, respectively.

[0088] Fig.13 It is a detailed mechanism diagram of CAACs removing OFCs. After adding CAACs, the conformation of the protein changes, resulting in a weakened binding of hexanal to the protein. At the same time, CAACs molecules will compete with hexanal for protein binding sites. At this time, the binding force of hexanal to the protein is weakened, and it cannot compete with CAACs with stronger binding force. As a result, hexanal is eventually squeezed out and the odor is eliminated. The present invention provides information on the mechanism of spices removing chicken odor, which is beneficial to regulating the odor of chicken and improving the edible quality and commercial acceptance of meat products.

[0089] Although the embodiments of the present invention have been disclosed as above, they are not limited to the applications listed in the specification and the implementation modes, and they can be fully applied to various fields suitable for the present invention. For those familiar with the art, additional modifications can be easily implemented. Therefore, without departing from the general concept defined by the claims and the scope of equivalents, the present invention is not limited to the specific details and the illustrations shown and described herein.

Claims

1. A method for removing the odor of meat products based on the flavor molecular structure, characterized in that: Aroma-active compounds are used to occupy the binding sites of odor compounds on myofibrillar protein, thereby releasing the odor compounds and removing the odor.

2. The method for removing odor from meat products based on flavor molecular structure according to claim 1, characterized in that: Odor compounds include: hexanal, nonanal, benzaldehyde, 1-pentanol, and 1-octen-3-ol.

3. The method for removing peculiar smell of meat products based on flavor molecular structure according to claim 1, characterized in that: The odorous compound is hexanal.

4. The method for removing the peculiar smell of meat products based on the flavor molecular structure according to claim 3, characterized in that: The binding sites of odor compounds on myofibrillar proteins include: A2-R18-E89-D90-Y118-R148-Q149E150-P152-A151, T335-D336-K349-Y353L300-I292-P298-K297-L332-Q291, V589-I470-N474-D472-K575-A576-A578-N592-D590.

5. The method for removing odor from meat products based on flavor molecular structure according to claim 4, characterized in that: Aroma active compounds include: geraniol, D-limonene, acetophenone.

6. The method for removing odor from meat products based on flavor molecular structure according to claim 1, characterized in that: The method of using aroma active compounds to occupy the binding sites of odor compounds on myofibrillar protein comprises: using spices containing aroma active compounds to treat meat products having odor compound binding sites on myofibrillar protein.

7. The method for removing the peculiar smell of meat products based on the flavor molecular structure according to claim 6, characterized in that: The method of using spices to process meat products is: pickling.

8. A meat product, characterized in that: The meat product is pretreated by the method according to any one of claims 1 to 7.

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