Meat-flavor paste-like flavoring based on optimization of aroma characteristics and preparation process thereof

Abstract

The present application relates to the technical field of food flavor additive, and provides a meat-flavored paste-like essence based on optimization of aroma characteristics and a preparation process thereof. The preparation process hydrolyzes protein raw materials by controlling enzymolysis parameters, generates key aroma precursors through Maillard reaction and lipid thermal oxidative degradation, and prepares the paste-like essence after dehydration concentration and freshening deployment. The obtained product has the characteristics of rich meat aroma, natural and persistent aroma, and uniform and stable texture, and is suitable for food seasoning processing.

Description

Technical Field

[0001] This invention relates to the field of food flavor additives, and in particular to a meat-flavored paste flavoring optimized based on aroma properties and its preparation process. Background Technology

[0002] In modern food processing and condiment science, meat-flavored paste flavorings, as core food additives with complex rheological properties and highly concentrated flavor structures, are widely used in the manufacture of meat products, convenience foods, and compound seasonings. Their core development logic is typically based on biomimetic principles, which involve simulating the thermo-induced chemical changes of natural meat during high-temperature cooking. Protease technology is used to degrade macromolecular muscle fibrous proteins and connective tissue into peptides and free amino acids. Subsequently, exogenous reducing sugars and specific amino acids are introduced, inducing a cascade of chemical reactions under thermodynamic conditions, including Maillard reactions, Streak degradation, and lipid thermal oxidation, to obtain a paste-like final product with a dark color and rich caramel aroma.

[0003] However, traditional atmospheric pressure high-temperature cooking processes suffer from inherent mass transfer and reaction kinetic bottlenecks in practical industrial applications. In conventional Maillard reaction systems, to achieve the required solids content for the final paste product through water evaporation, the reaction system must be in a continuous high-temperature boiling state. The intense vaporization of water creates a strong airflow stripping effect, inevitably carrying away a large number of newly synthesized high vapor pressure, low boiling point core sulfur-containing flavor molecules (such as low-threshold thiols and thiazole derivatives that impart meaty aromas) from the reaction system, resulting in a significant loss of characteristic aromas. Simultaneously, a single linear substrate is insufficient to construct a three-dimensional flavor network. Furthermore, continuous high-temperature thermal stress and open-top cooking lead to a sharp decrease in water activity and an exponential increase in viscosity in the later stages of the process, resulting in severe localized overheating. This change in physical state forcibly pushes the chemical reaction pathway towards the formation of advanced glycation end products (AGEs) and accelerates the deep oxidation of the lipid matrix and the secondary cleavage and polymerization of sulfur-containing intermediates. This not only weakens the freshness of the flavoring, causing unpleasant chemical or burnt tastes, but also makes the final product highly susceptible to physical and chemical instability problems such as oil-water separation and flavor decay during storage. Summary of the Invention

[0004] To address the aforementioned technical problems, this invention provides a preparation process for a meat-flavored paste flavoring based on optimized aroma properties, and the meat-flavored paste flavoring obtained by this process.

[0005] According to one aspect of the present invention, a preparation process for a meat-flavored paste flavoring optimized based on aroma properties is provided. This preparation process includes the following steps: first, extraction of a plant flavor matrix is ​​performed by enzymatic extraction of Allium species using cellulase, followed by liquid-solid separation to obtain a plant-derived sulfur-containing precursor extract containing soluble sulfur-containing flavor precursors; next, enzymatic hydrolysis of a meat-derived substrate is performed by hydrolyzing basic meat-derived proteins using protease, and after reaching a predetermined endpoint, the enzyme is inactivated by heating to obtain a meat-derived polypeptide hydrolysate; subsequently, emulsification and substrate assembly are performed by mixing the plant-derived sulfur-containing precursor extract with the meat-derived polypeptide hydrolysate, and... Reducing sugars, free sulfur-containing amino acids, thiamine, carnosine, and lipid matrix are added to a mixed system, which is then sheared and emulsified to form an oil-in-water emulsion system. A pressurized, closed-loop thermal reaction is then performed, placing the oil-in-water emulsion system in a sealed reactor and conducting a constant-temperature thermal reaction under pressure. Finally, flash quenching and dehydration under reduced pressure are carried out. After the thermal reaction, the sealed reactor is connected to a pre-vacuumed buffer tank for transient flash evaporation to cool the material. Subsequently, constant-temperature dehydration and concentration are performed under vacuum and low pressure. After dehydration and concentration, disodium inosinate is added for flavor enhancement, resulting in a meat-flavored paste-like flavoring. The introduction of a plant-based flavor matrix breaks through the traditional limitation of relying solely on the hydrolysis of meat proteins. It mixes natural plant-derived secondary metabolites containing sulfur molecules with an animal-derived amino acid library, resulting in cross-boundary chemical replacement and recombination under thermal stress, providing a multi-dimensional material basis for constructing a complex, three-dimensional meat aroma.

[0006] Preferably, in the plant flavor matrix extraction step, the Allium species is onion. More preferably, the enzymatic extraction conditions include: adding cellulase to an acidic buffer solution with a pH of 5.4 to 5.6 and extracting at a constant temperature of 45°C to 55°C; after extraction, raising the temperature to above 95°C for enzyme inactivation. Controlling the extraction temperature to 45°C to 55°C and the pH to 5.4 to 5.6 is crucial for precisely matching the optimal spatial conformation of the cellulase. If the temperature or pH deviates from this range, it will lead to changes in the charge state of the enzyme's active site or protein denaturation, significantly reducing the efficiency of plant cell wall disruption. It should be noted that the high temperature during enzyme inactivation causes the original thiosulfinate to further convert into more stable secondary sulfur-containing compounds such as diallyl disulfide and methyl propyl disulfide. These sulfur-containing substances serve as key donors of sulfur atoms in the subsequent Maillard reaction, constituting the main active components of plant-derived sulfur-containing flavor precursors. The onion polysaccharides released during cell wall disruption not only provide a protective colloidal effect at this moment, but the oligosaccharide fragments produced by their hydrolysis can also provide an auxiliary sugar source for subsequent reactions.

[0007] Preferably, in the enzymatic hydrolysis step of the meat substrate, the protease includes papain as an endopeptidase and flavor protease as an exopeptidase. More preferably, the hydrolysis conditions include: pulverizing the basic meat protein and mixing it with deionized water, then subjecting it to heat denaturation at 80°C to 90°C; subsequently cooling to 50°C to 60°C, adjusting the pH of the system to 6.4 to 6.6, and sequentially adding the endopeptidase and exopeptidase for synergistic hydrolysis until the free amino nitrogen content is not less than 0.65 g / 100g and the degree of hydrolysis reaches 28% to 30%, at which point the temperature is raised to inactivate the enzymes. The pretreatment at 80°C to 90°C enables the unwinding of the higher conformation of myofibrils, fully exposing the cleavage sites in the hydrophobic core. Controlling the degree of hydrolysis between 28% and 30% is the critical point for balancing the flavor base and mouthfeel. If the degree of hydrolysis is below 28%, the release of free amino acids in the system will be insufficient, which will lead to a lack of core nitrogen-containing substrates in the subsequent Maillard reaction and a thin aroma. If the degree of hydrolysis is above 30%, it will lead to excessive breakage of polypeptide chains, weakening the macromolecular peptides that give the final product a rich and enveloping base flavor.

[0008] Preferably, by weight, the overall raw material input ratio of the preparation process of the present invention is as follows: 35 to 45 parts of basic meat protein, 8 to 12 parts of Allium spp., 8 to 12 parts of reducing sugar, 2 to 3 parts of free sulfur-containing amino acids, 0.3 to 0.5 parts of thiamine, 0.6 to 1.0 parts of carnosine, and 6 to 10 parts of lipid matrix; 0.2 to 0.4 parts of disodium nucleotides are added after dehydration and concentration; wherein, the mass ratio of basic meat protein to deionized water is 1:0.45 to 1:0.55; wherein, the reducing sugar is selected from at least one of D-xylose and glucose; the free sulfur-containing amino acid is L-cysteine ​​hydrochloride; the thiamine is thiamine hydrochloride; and the lipid matrix is ​​refined animal fat. The unique dipeptide structure of carnosine (β-alanyl-L-histidine) not only provides a free amino group, but its imidazole ring (pKa approximately 6.8) also possesses strong pH buffering capacity, which can resist microscopic pH decline caused by organic acid byproducts to a certain extent, thus ensuring the assembly pathway of nitrogen-containing heterocycles. The pKa value of the imidazole ring of carnosine is approximately 6.8, and its effective buffering range covers the pH range of 5.8 to 7.8. The initial pH of the reaction system of this invention is set at 6.20 to 6.40, which is exactly within the range where carnosine has a strong buffering capacity, effectively resisting the pH decrease caused by the accumulation of organic acids during the reaction. In addition, the imidazole ring of carnosine also has a known free radical scavenging ability, which helps to inhibit the expansion of lipid peroxidation chain reactions. If carnosine is not added or the amount added is too low, the pH of the system is prone to decline, leading to an increased tendency for sulfur-containing compounds to self-polymerize, while lipid oxidation is intensified, resulting in off-odors.

[0009] More preferably, the shear emulsification process involves injecting the molten lipid matrix into the mixing system and continuously shearing and emulsifying at a shear rate of not less than 8000 rpm, while adjusting the final pH of the system to be locked between 6.20 and 6.40. Under high shear, the fat is broken down into micron-sized oil droplets, and natural peptides, acting as surfactants, construct a stable oil-in-water (O / W) phase interface. This oil phase core will subsequently serve as an in-situ extraction reservoir for fat-soluble flavor molecules. Precisely locking the final pH in the slightly acidic to neutral range of 6.20 to 6.40 ensures the directional cleavage of thiamine and prevents the reverse hydrolysis of Schiff bases. Exceeding this range may lead to excessive cross-linking or reduce the conversion rate.

[0010] Preferably, prior to the isothermal thermal reaction under pressure, an induced pre-condensation stage is included: the system temperature is raised to 95°C to 105°C under atmospheric pressure boiling conditions and maintained for 30 to 50 minutes. Mild atmospheric pressure heating drives the amino and carbonyl groups to cross the activation energy barrier, completing large-scale primary nucleophilic addition to form Schiff bases. More preferably, the isothermal thermal reaction under pressure involves: sealing the pipeline connected to the atmosphere to make the reaction system gas-tight; forced heating to raise the core temperature of the system to 120°C to 130°C; due to the combined effects of water vaporization and solute boiling point elevation, the surface pressure within the system spontaneously rises to 0.10 MPa to 0.18 MPa; and the reaction is maintained at this temperature and pressure for 45 to 75 minutes. The 120°C to 130°C provides the higher activation energy required for Streck degradation, promoting the cyclization of sulfur-containing intermediates to form thiazoles and furanthiols. Controlling the pressure within this range is a key mechanism for achieving liquid-phase retention of volatile flavor compounds. According to the principle of gas-liquid equilibrium, the increase in total pressure of the system under closed pressurization reduces the proportion of gas phase partial pressure of low-boiling-point molecules, inhibiting their mass transfer driving force from the liquid phase to the gas phase. This results in them being retained more in the liquid phase and extracted and enriched by emulsified micro-oil droplets. If the pressure is too low, the system will boil violently, and water vapor entrainment will accelerate the escape of characteristic flavor compounds. If the reaction temperature and pressure are too high, the continuous high-temperature thermal stress will accelerate lipid oxidation and Maillard reaction towards deep browning, increasing the risk of generating undesirable byproducts.

[0011] Preferably, the transient flash evaporation depressurization process is as follows: The high-pressure sealed reactor is connected to a vacuum buffer tank, which has been pre-evacuated to an absolute pressure not exceeding 10 kPa, for depressurization. The effective volume of the vacuum buffer tank is not less than three times the effective volume of the sealed reactor to ensure that the absolute pressure of the system can be sufficiently reduced after connection. The absolute pressure of the system rapidly decreases from 0.20 MPa to 0.28 MPa during the reaction to 35 kPa to 45 kPa within 3 to 5 minutes. Under this low-pressure condition, the boiling point of water drops to approximately 72°C to 80°C. The water in the material undergoes violent boiling and vaporization under this pressure, absorbing a large amount of latent heat of vaporization, causing the core temperature of the material to rapidly drop below 80°C. This flash evaporation operation, which directly connects the reactor to a large-volume vacuum tank, utilizes the spontaneous boiling endothermic effect triggered by the sudden pressure drop to achieve rapid cooling. This is a typical application of mature vacuum flash evaporation cooling technology in the food industry. This physical quenching operation rapidly removes the thermodynamic driving force for the reaction to continue evolving towards higher glycosylation and deep browning, effectively inhibiting the further formation of burnt-tasting substances. More preferably, the isothermal dehydration and concentration process under vacuum and low pressure conditions is as follows: continuous vacuum is maintained at an absolute pressure of 20.0 kPa to 30.0 kPa, a compensating heat source is provided to the jacket, and the core temperature of the material is maintained at 60°C to 65°C for low-pressure water vaporization separation. According to the Clausius-Clapeyron equation, vacuum significantly lowers the boiling point of water, achieving the removal of redundant water without destroying heat-sensitive aromatic molecules.

[0012] More preferably, the isothermal dehydration and concentration process under vacuum and low pressure conditions also includes the step of adding rheology modifiers: when the concentration reaches a thick paste-like state, hydrated and swollen xanthan gum is drawn in under vacuum negative pressure for vacuum mixing; the endpoint determination criteria for isothermal dehydration and concentration are: the free water content of the material is reduced to 22.0% to 25.0% and the water activity is reduced to below 0.75, as monitored online. Xanthan gum forms a gel network with peptides and onion polysaccharides through hydrogen bonding, which helps stabilize the rheological structure of the paste and slows down the migration of water and volatile substances. A water activity below 0.75 is a key indicator for thermodynamically inhibiting the growth of spoilage microorganisms, which is beneficial to ensuring the long-term stability of the product. After dehydration and concentration are completed and the vacuum is released, disodium inosinate is added and mixed evenly when the material temperature drops below 65°C to ensure that its flavor-enhancing activity is not destroyed by high temperature.

[0013] Preferably, after the transient flash evaporation and depressurization dehydration steps, a post-processing step is also included: after dehydration and concentration are completed and the vacuum is released, when the temperature of the material in the reactor drops below 65°C, disodium nucleotides are added and stirred and mixed evenly in the reactor; then the paste material is pumped into a forced cooling heat exchanger, cooled to 35°C to 40°C in a closed pipeline, filtered through a mesh to remove particle agglomeration, and then sealed and filled under nitrogen purging conditions.

[0014] According to another aspect of the present invention, a meat-flavored paste flavoring with optimized aroma properties is provided, which is prepared by the above-described preparation process of the meat-flavored paste flavoring with optimized aroma properties.

[0015] Compared with the prior art, the present invention has the following beneficial effects: This invention overcomes the technical shortcomings of existing technologies, such as the easy escape of volatile flavor molecules and the tendency to produce a burnt taste during high-concentration cooking, by coupling the targeted catalytic recombination of multidimensional precursors with the dynamic isolation and control of the reaction system's phase state. The pressurized closed thermal reaction process of this invention effectively prevents the escape of high vapor pressure flavor molecules, enabling the system to complete deep Maillard synthesis in a pressurized liquid phase environment. This allows core flavor substances such as low-threshold polar sulfur-containing molecules and thiazole derivatives to accumulate in the lipid core at the oil-in-water interface, resulting in a significant improvement in the realism of the fragrance aroma, the impact of the top notes, and the layered texture of the broth base.

[0016] Simultaneously, the carnosine introduced in this invention acts as a pH buffer and free radical scavenger. Combined with flash quenching and vacuum isothermal dehydration technology, it utilizes the imidazole ring proton buffering effect and free radical scavenging ability of carnosine on a chemical scale to inhibit the disordered polymerization of sulfur-containing intermediates and the expansion of lipid peroxidation chain reactions. On a physical scale, it utilizes the endothermic effect induced by vacuum flash depressurization to rapidly reduce the system temperature, inhibiting the reaction process that leads to deep burnt bitterness and advanced glycosylation, and gently dehydrating at low temperatures. These mechanisms synergistically inhibit the formation of deep browning byproducts and oxidative degradation products, effectively improving the localized overheating problem caused by high water activity in the later stages, significantly improving the product's antioxidant and rheological stability, and significantly reducing the burnt taste and off-flavors commonly found in conventional high-temperature concentrated flavorings. Furthermore, the disodium inosinate is added at low temperatures after dehydration and concentration, fully preserving its umami-enhancing function and further improving the umami performance of the final product. Detailed Implementation

[0017] To comprehensively and clearly demonstrate the technical concept, reaction mechanism, and expected technical effects of this invention, the following detailed discussion, combining specific chemical reaction laws with the principles of materials science and food flavor engineering, elaborates on the specific preparation method, raw material specifications, and inherent reaction mechanism of the meat-flavored paste-like flavor involved in this invention. The core of this invention lies in solving the problems of characteristic flavor substance escape and high-temperature deep browning and deterioration through targeted catalytic recombination of multidimensional precursor substances and dynamic isolation control of the thermodynamic phase state of the reaction system. Regarding raw material selection, this invention strictly defines the purity and physicochemical properties of each component to ensure that the catalytic network is not interfered with by impurities and has a reproducible industrial basis. The basic meat source protein used is fresh pork hind leg or tenderloin that has passed veterinary inspection. After removing visible fascia and fat, it is pulverized into a uniform meat paste with a pore size of 3.0 to 5.0 mm. This particle size is an optimal choice for balancing mass transfer resistance and the specific surface area of ​​the enzymatic reaction. The plant flavor matrix is ​​made from fresh purple onions (Allium cepa L.) harvested no more than two weeks prior, whose cells contain a high concentration of S-alkyl(enyl)-L-cysteine ​​sulfoxide endogenous precursors. The cellulase used in the extraction process is derived from Trichoderma reesei (e.g., refined food-grade product from Novozymes), with an activity of no less than 50,000 U / g; the papain used for co-enzymatic hydrolysis has an activity of no less than 100,000 U / g, and the flavor protease has an activity of no less than 20,000 LAPU / g. The reducing sugar system uses refined food-grade D-xylose with a purity greater than 99.0% and anhydrous crystalline glucose with a purity greater than 99.5%; D-xylose, as a pentose, exhibits significantly higher carbonyl electrophilic reactivity in its straight-chain open-ring state than hexoses, making it a core driver for inducing the Maillard primary nucleophilic addition reaction. The free sulfur-containing amino acids in the system are L-cysteine ​​hydrochloride monohydrate with a purity greater than 99.0%; thiamine is food-grade thiamine hydrochloride (vitamin B1) with a purity greater than 98.0%. Carnosine (β-alanyl-L-histidine dipeptide) is required to be of biochemical reagent grade with a purity greater than 98.0%, and in this invention, it plays an auxiliary role in both pH buffering and free radical scavenging; the lipid emulsion matrix is ​​refined chicken fat with a peroxide value of less than 5.0 meq / kg and an acid value of less than 1.0 mg KOH / g; disodium inosinate (5′-disodium inosinate, I+G) with a purity of not less than 99.0% is added as a flavor enhancer at a low temperature stage after dehydration and concentration to avoid hydrolysis and degradation of phosphate ester bonds caused by high temperature; the rheology modifier is food-grade xanthan gum with a viscosity greater than 1200 cps in 1% potassium chloride solution. The reaction system constructed in this invention is based on the following chemical mechanism: First, cellulase specifically breaks the β-1,4-glycosidic bonds of the onion cell wall, which not only releases oligosaccharides that serve as protective colloids and auxiliary sugar sources for subsequent reactions, but also causes the onion vacuoles to collapse, activating alliinase to convert the substrate into unstable hyposulfonic acid intermediates and low-molecular-weight volatile sulfides.These primary sulfur-containing products are further transformed into relatively stable secondary sulfur-containing compounds such as diallyl disulfide and methyl propyl disulfide under the high temperature of the enzyme inactivation process, becoming important donors of sulfur atoms in subsequent reactions. These plant-derived sulfur-containing flavor precursors, mixed with high concentrations of free branched-chain amino acids and small peptides produced by the synergistic cleavage of pork by papain and flavor exopeptidase, constitute the diversified dual-source precursor pool of this invention. In the subsequent closed-system pressurized thermal reaction, the closed-system pressurization conditions (gauge pressure 0.10 to 0.18 MPa, corresponding to an absolute pressure of approximately 0.20 to 0.28 MPa) effectively suppressed the violent boiling of the system. According to the principle of gas-liquid equilibrium, the increase in the total pressure of the system under closed-system pressurization reduced the driving force for mass transfer of low-boiling-point volatile molecules to the gas phase, thereby effectively suppressing their escape. Hydrogen sulfide released by cysteine ​​under thermal drive rapidly undergoes cyclization and dehydration with furfural generated from xylose cleavage, which is conducive to the generation of characteristic broth-like aroma molecules with low olfactory threshold (such as 2-methyl-3-furanthiol); at the same time, the methylene imine bridge in the thiamine molecule is homolytically cleaved, releasing the complete thiazole ring skeleton (such as 4-methyl-5-(β-hydroxyethyl)thiazole), giving the product a profound roasted meat flavor. In this process, carnosine utilizes the pH buffering effect of its histidine residue side chain imidazole ring (pKa approximately 6.8) to absorb organic acid byproducts from carbohydrate degradation, thus stabilizing the system pH to a certain extent within a range favorable for the assembly of nitrogen-containing heterocycles. The pKa of the carnosine imidazole ring is approximately 6.8, and its effective buffering range (pKa±1) covers pH 5.8 to 7.8. The initial pH of the reaction system, 6.20 to 6.40, falls within this buffer zone. As the reaction progresses and organic acids accumulate, causing a decrease in pH, carnosine continues to exert its buffering effect. Simultaneously, the known free radical scavenging activity of the carnosine imidazole ring helps quench alkoxy and peroxy free radicals generated during lipid peroxidation, inhibiting the expansion of the oxidation chain reaction. Furthermore, the oil-in-water interface formed by refined chicken fat under high shear conditions, based on the principle of "like dissolves like," allows for the in-situ extraction and enrichment of these trace flavor molecules retained in the liquid phase by the enclosed environment. Finally, through physical phase change control—specifically, utilizing vacuum flash evaporation to instantly establish a pressure difference and induce vigorous boiling of water to absorb a large amount of latent heat of vaporization—the material is rapidly cooled, effectively inhibiting the reaction process of advanced glycation end products (AGEs) and undesirable byproducts. Subsequently, a seamlessly integrated isothermal vacuum dehydration technology, based on the Clausius-Clapeyron equation, removes excess water at a low temperature of 60-65°C. This is supplemented by a gel network structure formed by xanthan gum and peptides to stabilize the system structure, ultimately completing the concentration and textural shaping of the flavoring while controlling the formation of a burnt flavor. After dehydration and concentration, disodium inosinate is added when the material cools to below 65°C, fully utilizing its stable flavor-enhancing function at low temperatures to further refine the complex flavor of the final product.

[0018] In order to objectively and systematically quantify the technical differences in microscopic molecular composition, macroscopic antioxidant stability and sensory dimensions between the meat-flavored paste flavorings prepared in the embodiments of the present invention and the comparative examples, the following four standardized testing systems are established. The first item was absolute quantitative analysis of core flavor compounds (GC-MS). After simultaneous distillation extraction (SDE) to enrich volatiles, the sample was injected into a gas chromatography-mass spectrometry instrument equipped with a DB-WAX polar capillary column (60 m × 0.25 mm × 0.25 μm). The temperature program was set to initially hold at 40℃ for 3 minutes, increase to 200℃ at 5℃ / min, and then increase to 240℃ at 10℃ / min and hold for 5 minutes. 2-Octanol was used as an internal standard, and the absolute concentrations of 2-methyl-3-furanthiol (hereinafter referred to as 2-M-3-F, the fingerprint molecule of broth aroma, quantitative ion m / z 114) and 4-methyl-5-(β-hydroxyethyl)thiazole (the characteristic molecule of roast meat aroma, quantitative ion m / z 143) were quantified using selected ion monitoring (SIM) mode. The results are expressed in micrograms per kilogram (μg / kg, i.e., ppb). The second item is the stability evaluation of lipid peroxidation products (TBARS determination). According to GB5009.181-2016 standard, the finished fragrance was placed in an accelerated oxidation incubator at 60℃ for 7 days with the container open. Subsequently, samples were taken and reacted with thiobarbituric acid reagent in a boiling water bath for color development. The absorbance was measured at 532 nm. The results are expressed as malondialdehyde equivalent (mg MDA / kg). The lower the value, the stronger the antioxidant capacity and the better the antioxidant stability of the system. The third item is rheological and physical state testing. The apparent viscosity (Pa·s) of the paste was measured using a Brookfield rotational viscometer at 25℃ and a rotor speed of 20 rpm. Simultaneously, the water activity (aw) and free water content (%) of the final product were measured using a water activity meter and an infrared rapid moisture analyzer at 25℃. The fourth item is the professional sensory flavor profile evaluation. Based on the ISO 8586 standard, an evaluation team of 15 experts with national-level sensory evaluation qualifications was selected and assembled. The test was conducted in a standardized sensory laboratory, using the 15 cm unstructured linear scale method. Scores were given for three dimensions: "top aroma and freshness", "rich and mellow broth", and "unpleasant burnt / chemical off-flavors". 0 points represent no flavor, and 15 points represent an extremely strong flavor. The arithmetic mean was taken as the final sensory evaluation conclusion.

[0019] Example 1 provides a preferred formulation of a meat-flavored paste flavoring based on optimized aroma properties. First, a plant flavor matrix extraction was performed: 10.00 kg of fresh purple onion was weighed, peeled, chopped, and homogenized with 10.00 kg of deionized water; the pH was adjusted to 5.50 using 10% citric acid, and 20.0 g of cellulase was added. Extraction was carried out at 50°C with constant stirring (60 rpm) for 2.5 hours; subsequently, high-pressure steam was rapidly introduced to raise the temperature to 95°C and incubated for 15 minutes to inactivate the enzyme. The extract was then centrifuged using a horizontal decanter centrifuge, collecting a light amber-colored extract rich in onion oligosaccharides and soluble sulfur-containing flavor precursors. Next, enzymatic hydrolysis of the meat substrate was performed: 40.00 kg of minced pork hind leg meat and 20.00 kg of deionized water were put into a 200 L enzymatic hydrolysis reactor with high shear function and treated at 85℃ for 15 minutes to dehydrogenate the higher proteins; cooled to 55℃, the pH was adjusted to 6.50 with sodium carbonate solution, and 40.0 g of papain and 80.0 g of flavor protease were added in sequence. The mixture was synergistically hydrolyzed at 55℃ and 120 rpm for 3.0 hours; the degree of hydrolysis was determined by formaldehyde titration to be 29.5% and the amino nitrogen content was 0.69 g / 100g. The temperature was immediately raised to 90℃ and kept at that temperature for 20 minutes to inactivate the enzyme. Next, emulsification and substrate assembly were performed: all onion extract was pumped into the meat-derived enzymatic hydrolysate, followed by the sequential addition of 6.50 kg D-xylose, 3.50 kg glucose, 2.50 kg L-cysteine ​​hydrochloride, 0.40 kg thiamine hydrochloride, and 0.80 kg carnosine; then, 8.00 kg of refined chicken fat, heated to 60°C and completely melted, was injected. A high-shear homogenizer was used for continuous emulsification at 8000 rpm for 15 minutes, and a trace amount of sodium carbonate was used to lock the final pH to 6.30, forming a stable oil-in-water emulsion with micron-sized oil droplets. The process then proceeded to the induced pre-condensation stage: the system was steadily heated to 100°C under normal pressure and maintained for 40 minutes, driving the large-scale generation of Schiff bases. The process then proceeds to the pressurized, sealed thermal reaction stage: The exhaust valve is completely sealed using a pneumatic system, and the heat transfer oil is forced to heat the core temperature inside the reactor, causing it to jump to 125°C within 15 minutes. Due to the combined effects of water vaporization and the increased boiling point of the high-concentration solute, the gauge pressure spontaneously stabilizes at 0.14 MPa (corresponding to an absolute pressure of approximately 0.24 MPa). Under this pressurized condition, a constant temperature and pressure are maintained for 60 minutes for deep reaction. Immediately after the thermal reaction, flash quenching is performed: the heat source is cut off, and the valve connecting to a large-capacity vacuum buffer tank (with a volume not less than three times the volume of the reactor) that has been pre-evacuated to an absolute pressure of approximately 8 kPa is opened. The absolute pressure of the system drops sharply from approximately 0.24 MPa to approximately 40 kPa within 4 minutes. Under this low-pressure condition, the boiling point of water drops to approximately 76°C, causing the water in the material to boil and vaporize violently, absorbing a large amount of latent heat, and the core temperature of the material rapidly drops to 76°C.Subsequently, vacuum dehydration and concentration were continued: the liquid ring vacuum pump was started to maintain the system absolute pressure at 25.0 kPa, and 75°C warm water was circulated through the jacket to maintain the material at a constant boiling temperature of 65°C. After vacuum dehydration for about 1.8 hours, when the material turned into a dark brown, thick frosty consistency and the stirring torque increased significantly, 0.50 kg of fully hydrated xanthan gum was sucked in under negative pressure and vacuum mixing was continued for 15 minutes. Online detection showed that the free water content was 23.2% and the water activity was 0.68, at which point the vacuum was released. When the material temperature dropped to about 60°C, 0.30 kg of disodium inosinate was added and stirred until homogeneous. The finished hot paste was forcibly cooled to 38°C, passed through an 80-mesh filter, and then sealed and packaged with nitrogen to obtain the meat-flavored paste-like flavoring product.

[0020] Example 2 provides a meat-flavored paste flavoring with parameters at the lower limit of the claims and a changed substrate ratio. First, a plant-based flavor matrix extraction was performed: 8.00 kg of onion homogenate was weighed, pH adjusted to 5.40, and 16.0 g of cellulase was added. Extraction was carried out at 45°C for 2.5 hours, followed by enzyme inactivation at 95°C and centrifugation to collect the extract. Next, enzymatic hydrolysis of the meat substrate was performed: 35.00 kg of minced meat and 17.50 kg of water were subjected to heat denaturation at 80°C, followed by cooling to 50°C, pH adjusted to 6.40, and 35.0 g of papain and 70.0 g of flavor protease were added. Enzymatic hydrolysis was carried out for 3.0 hours, achieving a degree of hydrolysis of 28.2% and an amino nitrogen content of 0.65 g / 100g. Enzyme inactivation was then performed at 90°C. Next, the substrate was assembled: the two liquids were mixed, and 8.00 kg of D-xylose (glucose not included in this example), 2.00 kg of L-cysteine ​​hydrochloride, 0.30 kg of thiamine hydrochloride, and 0.60 kg of carnosine were added. 6.00 kg of molten chicken fat was injected, and the mixture was sheared at 8000 rpm for 15 minutes. The pH was adjusted to 6.20. After pre-condensation, a pressurized, closed-loop thermal reaction was initiated: the temperature was forcibly raised to 120°C, the gauge pressure was stabilized at 0.10 MPa (corresponding to an absolute pressure of approximately 0.20 MPa), and the reaction was maintained at this temperature and pressure for 45 minutes. Flash quenching was then performed, and a pre-vacuum buffer tank was connected. The absolute pressure of the system decreased to approximately 42 kPa within 5 minutes, and the temperature dropped to 75°C. Finally, dehydration was performed under reduced pressure: dehydration was carried out at 20.0 kPa and 60°C, with 0.40 kg of xanthan gum added at the end. Dehydration was stopped when the moisture content was measured to be 22.5% and the water activity was 0.65. After releasing the vacuum and allowing the material to cool to approximately 60°C, add 0.30 kg of disodium inosinate and stir until homogeneous. After further cooling to 35°C, fill the package to obtain the flavoring product.

[0021] Example 3 provides a meat-flavored paste-like flavoring with parameters at the upper limit of the claims and a substrate ratio shifted towards being rich in free amino acids. First, the plant flavor matrix was extracted: 12.00 kg of onion homogenate was taken, pH adjusted to 5.60, 24.0 g of cellulase was added, and extraction was carried out at 55°C for 2.5 hours, followed by enzyme inactivation and centrifugation at 95°C. Second, the meat-derived substrate was enzymatically hydrolyzed: 45.00 kg of minced meat and 22.50 kg of water were taken, denatured at 90°C, then cooled to 60°C, pH adjusted to 6.60, 45.0 g of papain and 90.0 g of flavor protease were added, and enzymatic hydrolysis was carried out for 3.0 hours, achieving a degree of hydrolysis of 29.8% and an amino nitrogen content of 0.71 g / 100g, followed by enzyme inactivation at 90°C. Substrate assembly: After mixing, add 12.00 kg glucose (xylose-free in this example), 3.00 kg L-cysteine ​​hydrochloride, 0.50 kg thiamine hydrochloride, and 1.00 kg carnosine. Inject 10.00 kg molten chicken fat, emulsify at 8000 rpm, and adjust pH to 6.40. Pre-condensation followed by pressurization: Heat to 130°C, reaching a gauge pressure of 0.18 MPa (corresponding to an absolute pressure of approximately 0.28 MPa), and maintain this temperature and pressure for 75 minutes. Flash quenching: Connect to a pre-vacuum buffer tank; the absolute pressure of the system drops to approximately 43 kPa within 4 minutes, and the material temperature drops to 78°C. Dehydration under reduced pressure: Dehydrate at 30.0 kPa and 65°C, adding 0.60 kg xanthan gum; stop when the moisture content reaches 24.8% and the water activity is 0.73. After releasing the vacuum, allow the material to cool to approximately 60°C, then add 0.30 kg of disodium inosinate and stir until homogeneous. Cool to 40°C and then fill into vials to obtain the flavoring product.

[0022] Example 4, based on Example 1, specifically altered the proportion of the sugar substrate to examine the balance between the Maillard reaction rate and the thickness of the base aroma. Except for the reducing sugar ratio, the amounts of other components and process parameters remained consistent with Example 1, specifically: 40.00 kg of minced pork hind leg, 20.00 kg of deionized water, 10.00 kg of onion, 2.50 kg of L-cysteine ​​hydrochloride, 0.40 kg of thiamine hydrochloride, 0.80 kg of carnosine, 8.00 kg of refined chicken fat, 0.50 kg of xanthan gum, and 0.30 kg of disodium inosinate (added after dehydration); the reaction temperature was 125°C, the gauge pressure was 0.14 MPa, and the holding time was 60 minutes; the flash evaporation and vacuum dehydration conditions (25.0 kPa, 65°C) were consistent with Example 1. The only difference lies in the substrate assembly step three, where the ratio of reducing sugars is changed to: 2.00 kg D-xylose and 8.00 kg glucose. Since D-xylose, as a pentose, provides a higher initial reaction rate, while hexose glucose provides a richer precursor for caramelized melanin-like macromolecules, this ratio adjustment aims to verify the adaptability of the catalytic system of this invention to reducing sugars of different chain lengths and the stability of the fatty phase in retaining different sugar cleavage characteristics (such as furanaldehyde derivatives), ultimately yielding a meat-flavored paste-like flavor that meets the standards.

[0023] Example 5, based on Example 1, adjusted the thermal reaction time within the pressurized closed system to investigate the influence of deep degradation kinetics. The amounts of each component were consistent with Example 1, specifically: 40.00 kg minced pork hind leg, 20.00 kg deionized water, 10.00 kg onion, 6.50 kg D-xylose, 3.50 kg glucose, 2.50 kg L-cysteine ​​hydrochloride, 0.40 kg thiamine hydrochloride, 0.80 kg carnosine, 8.00 kg refined chicken fat, 0.50 kg xanthan gum, and 0.30 kg disodium inosinate (added after dehydration). The pretreatment steps of plant extraction and dual-enzyme hydrolysis were consistent with Example 1. During the pressurized closed thermal reaction stage, the core temperature was forcibly raised to 125°C, and the gauge pressure was controlled at 0.14 MPa, but the time for the constant temperature and pressure deep reaction was extended from 60 minutes in Example 1 to 75 minutes. The subsequent flash quenching and vacuum isothermal dehydration (25 kPa, 65°C) operations were performed as usual. Finally, xanthan gum was added for setting, and after dehydration, disodium inosinate was added and the product was filled. This example was used to verify the effect of extending the pressurized thermal stress time on the product's flavor indicators and by-product formation levels, provided that carnosine provides pH buffering and antioxidant protection.

[0024] Comparative Example 1 aimed to verify the role of carnosine in pH buffering and antioxidant mechanisms. Its entire preparation process, temperature, pressure (125°C pressurized reaction, flash vacuum dehydration), and all matrix ingredients (meat hydrolysate, onion extract, sugars, amino acids, lipids), as well as the addition of disodium flavor nucleotides after dehydration, were completely consistent with Example 1. The only difference was that, in step three, during emulsification and substrate assembly, carnosine was not added, and an equal weight (0.80 kg) of deionized water was used to make up the total weight of the system. The flavor sample of Comparative Example 1 was obtained.

[0025] Comparative Example 2 aimed to verify the role of "cellulase-assisted sulfur-containing precursor extract from Allium species" as a component of a multi-flavor network in the dual-source precursor pool. All process flows, enzymatic hydrolysis parameters, and pressurized dehydration conditions were identical to those in Example 1. The differences were: step one was completely omitted, and purple onion and cellulase were no longer used for extraction; in step three, during substrate assembly, 10.00 kg of purified deionized water was pumped into the reaction system instead of 10.00 kg of onion extract. The amounts of all other components (including 0.80 kg of carnosine, etc.), the addition of disodium 5-nucleotides (0.30 kg) after dehydration, and subsequent process conditions were consistent with Example 1. A flavor sample for Comparative Example 2 was obtained.

[0026] Comparative Example 3 aims to verify the effectiveness of the coherent thermodynamic phase control mechanism of the present invention, which involves "pressurized closed thermal reaction - flash evaporation - low-temperature vacuum dehydration". This comparative example used the exact same raw material ratio as Example 1 (including all components such as carnosine, onion extract, sugar, and amino acids), but completely reverted to the traditional industrial atmospheric pressure open-top cooking process. Specifically, after emulsification, the materials were placed in a reactor, with the exhaust valve at the top of the reactor fully open to the atmosphere. High-temperature heat transfer oil was introduced into the jacket, raising the system temperature to 105°C and maintaining boiling at this temperature. To achieve the same concentration and dehydration endpoint (approximately 23% moisture), this open-top cooking was continued at 105°C for 3.5 hours. During this period, the system viscosity increased significantly. No flash evaporation cooling was performed, nor was any vacuum intervention. After the reaction, the material was directly cooled and discharged. When cooled to approximately 60°C, 0.30 kg of disodium inosinate was added and stirred until homogeneous. The flavor sample of Comparative Example 3 was obtained.

[0027] Comparative Example 4 aimed to verify the effect of a specific dual-enzyme system on the structure of substrate peptides and its contribution to the final flavor. The subsequent Maillard reaction, pressurized synthesis, vacuum concentration, and the addition of excipients such as onion extract and carnosine, as well as the addition of disodium flavor nucleotides after dehydration, were all consistent with Example 1. The difference lay in step two, the enzymatic hydrolysis of the meat-derived substrate: papain and flavor protease were completely omitted. Instead, a single industrial-grade alkaline protease (activity 200,000 U / g) was added and hydrolyzed for 3 hours at 55°C and pH adjusted to 7.50. This operation generated a large number of hydrophobic amino acid-exposed bitter peptides, with a free amino nitrogen content of only 0.41 g / 100g. The enzyme was then inactivated by heating, and the pH was adjusted to 6.30 before proceeding to subsequent processes. The flavor sample of Comparative Example 4 was obtained.

[0028] Based on the standardized physicochemical tests and expert sensory evaluations described above, the comprehensive performance test results of each group of samples are shown in the table below: Sample number 2-Methyl-3-furanthiol content (μg / kg) 4-Methyl-5-(β-hydroxyethyl)thiazole content (μg / kg) TBARS value after accelerated oxidation (mg MDA / kg) endpoint water activity (aw) Apparent viscosity of the paste (Pa·s) Sensory evaluation: Freshness and vibrancy of the top notes (out of 15) Sensory qualities: The rich flavor of the broth (out of 15) Sensory characteristics: Unpleasant burnt or off-flavor (out of 15) Example 1 485.6 312.4 1.85 0.68 85.4 14.2 14.5 0.5 Example 2 392.1 258.9 2.15 0.65 78.6 13.5 13.0 0.8 Example 3 415.8 345.2 2.08 0.73 92.1 13.8 13.9 1.1 Example 4 428.3 290.5 1.95 0.68 86.8 13.9 14.1 0.7 Example 5 478.5 338.6 2.35 0.69 88.5 14.0 14.3 1.5 Comparative Example 1 215.4 85.6 5.68 0.68 84.2 7.5 8.2 6.8 Comparative Example 2 285.2 210.6 2.20 0.68 85.0 8.5 10.5 1.5 Comparative Example 3 85.2 92.3 8.95 0.69 145.6 4.2 5.5 12.5 Comparative Example 4 195.6 155.8 2.45 0.67 65.4 6.5 5.5 9.8 From the above data, the role and technical effect of the technical features claimed in this invention can be analyzed. First, comparing Example 1 with Examples 2 to 5, it can be found that the content of characteristic aromatic compounds in all examples is at a high level (2-M-3-F is higher than 390 μg / kg), and the oxidative stability is good, indicating that when the parameters within the scope of protection of this invention fluctuate within a certain range, they can still firmly support the overall technical effect. In Example 5, the pressurized reaction time was extended to 75 minutes. The content of characteristic flavor substances was at a similar level to that in Example 1, but the TBARS value and the score for unpleasant burnt off-flavors were both increased (2.35 mg MDA / kg and 1.5 points), indicating that although the extension of the reaction time contributes to the accumulation of flavor substances, it is accompanied by an increase in oxidative side reactions and a tendency for deep browning. Therefore, the 60-minute reaction time set in Example 1 achieved a better balance between flavor accumulation and by-product control. Next, the results of the comparative examples are analyzed: In Comparative Example 1, since carnosine was not added, the reaction system lacked an effective pH buffer during the accumulation of organic acid by-products, and the free radical scavenging function provided by carnosine was lost. This is reflected in a significant decrease in the content of nitrogen-containing heterocyclic molecules such as 4-methyl-5-(β-hydroxyethyl)thiazole (from 312.4 to 85.6 μg / kg). Simultaneously, without carnosine-assisted antioxidant activity, lipid peroxidation was significantly aggravated, with the TBARS value rising to 5.68 mg MDA / kg, exhibiting a noticeable oxidative off-flavor. In Comparative Example 2, due to the absence of onion extract, the system lacked the supplementation of sulfur-containing multidimensional precursors, resulting in a decrease in 2-M-3-F content to 285.2 μg / kg and thiazole content to 210.6 μg / kg, both significantly lower than in Example 1. In addition to the decrease in the content of the two quantitatively detectable target flavor compounds, the absence of abundant organosulfur compounds and oligosaccharides in the onion extract also led to a homogenization of the overall flavor profile, manifested in a significant reduction in "top aroma and freshness" and "broth base" in sensory evaluation (8.5 and 10.5 points, respectively). Comparative Example 3 represents the results of a traditional atmospheric pressure open-air cooking process. During the open-boiling process at 105°C for 3.5 hours, the steam distillation effect carried away a large amount of low-boiling-point 2-M-3-F from the system, with a final retention of only 85.2 μg / kg, which is only 17.5% of that in Example 1. In addition, during the later stage of atmospheric pressure boiling with continuous evaporation of water, the local water activity decreased while the temperature remained high, and the system evolved towards advanced glycosylation (AGEs) and deep carbonization. This not only caused the apparent viscosity of the paste to rise abnormally to 145.6 Pa·s (indicating severe charring and caking), but also significantly aggravated lipid oxidation (TBARS reached 8.95 mg MDA / kg), and the sensory evaluation showed a burnt and bitter off-flavor score as high as 12.5 points.These data demonstrate that the integrated process control mechanism of this invention—"pressurized closed-loop trapping of volatiles—vacuum flash quenching to inhibit deep-seated reactions—vacuum low-temperature and gentle dehydration for setting"—has a significant effect on preserving characteristic flavor and inhibiting undesirable byproducts. Finally, Comparative Example 4, due to the use of a non-specific alkaline protease for hydrolysis under slightly alkaline conditions, had insufficient hydrolysis (amino nitrogen only 0.41 g / 100g), failing to effectively release sufficient free amino acids to participate in the subsequent Maillard reaction; simultaneously, the large number of peptide fragments with exposed hydrophobic amino acid residues produced brought a distinct bitter base flavor, resulting in a lower broth base flavor score (5.5 points) and a higher burnt off-flavor score (9.8 points) for the final product. It should be noted that, in addition to the different enzyme types, Comparative Example 4 also differed from Example 1 (pH 6.50) in its hydrolysis pH environment (pH 7.50). Therefore, the data for Comparative Example 4 reflects the combined effect of changes in enzyme type and hydrolysis conditions, rather than the effect of a single enzyme type variable. In summary, there is a synergistic relationship between the raw material system ratio and process parameters of the present invention. The absence of core technical features or their replacement by traditional methods will lead to varying degrees of decline in the flavor quality and stability of the final product, thus verifying the technological advancement and practical value of the present invention compared to the prior art.

Claims

1. A preparation process for a meat-flavored paste-like flavoring based on optimized aroma properties, characterized in that, The preparation process includes the following steps: S1. Extraction of plant flavor matrix: Enzymatic extraction of Allium species using cellulase, followed by liquid-solid separation to obtain plant-derived sulfur-containing precursor extract containing soluble sulfur-containing flavor precursors. S2. Meat substrate enzymatic hydrolysis: The basic meat protein is hydrolyzed using protease. After the hydrolysis reaches the predetermined endpoint, the temperature is raised to inactivate the enzyme, and meat peptide hydrolysate is obtained. S3. Emulsification and substrate assembly: The plant-derived sulfur-containing precursor extract is mixed with the meat-derived polypeptide hydrolysate, and reducing sugar, free sulfur-containing amino acids, thiamine, carnosine and lipid matrix are added to the mixture. The mixture is then emulsified by shearing to form an oil-in-water emulsion system. S4. Pressurized closed thermal reaction: The oil-in-water emulsion system is placed in a closed reaction vessel and subjected to a constant temperature thermal reaction under pressure. S5. Flash quenching and depressurization: After the thermal reaction is completed, the closed reaction vessel is connected to a pre-vacuumed buffer tank for transient flash quenching to depressurize the material and cool it down. Then, constant temperature dehydration and concentration are carried out under vacuum and low pressure conditions. After the dehydration and concentration are completed, disodium nucleotides are added for flavor enhancement and blending to obtain meat-flavored paste flavoring.

2. The preparation process of the meat-flavored paste flavoring based on optimized aroma properties according to claim 1, characterized in that, In step S1, the Allium plant is onion; The conditions for the enzymatic extraction include: adding the cellulase to an acidic buffer solution with a pH of 5.4 to 5.6 and extracting at a constant temperature of 45°C to 55°C; after extraction, raising the temperature to above 95°C for enzyme inactivation treatment.

3. The preparation process of the meat-flavored paste flavoring based on optimized aroma properties according to claim 1, characterized in that, In step S2, the protease includes papain as an endopeptidase and flavor protease as an exopeptidase. The hydrolysis reaction conditions include: pulverizing the basic meat protein and mixing it with deionized water, then performing heat denaturation treatment at 80°C to 90°C; subsequently cooling to 50°C to 60°C, adjusting the pH of the system to 6.4 to 6.6, and sequentially adding the endopeptidase and the exopeptidase for synergistic hydrolysis until the free amino nitrogen content is not less than 0.65 g / 100g and the degree of hydrolysis reaches 28% to 30%, at which point the temperature is raised to inactivate the enzymes.

4. The preparation process of the meat-flavored paste flavoring based on optimized aroma properties according to claim 1, characterized in that, The overall raw material input ratio for the preparation process, by weight, is as follows: 35 to 45 parts of basic meat protein, 8 to 12 parts of Allium genus, 8 to 12 parts of reducing sugar, 2 to 3 parts of free sulfur-containing amino acids, 0.3 to 0.5 parts of thiamine, 0.6 to 1.0 parts of carnosine, and 6 to 10 parts of lipid matrix; 0.2 to 0.4 parts of disodium inosinate; wherein the mass ratio of basic meat protein to deionized water is 1:0.45 to 1:0.

55. Wherein, the reducing sugar is selected from at least one of D-xylose and glucose; the free sulfur-containing amino acid is L-cysteine ​​hydrochloride; the thiamine is thiamine hydrochloride; and the lipid matrix is ​​refined animal fat.

5. The preparation process of the meat-flavored paste flavoring based on optimized aroma properties according to claim 1, characterized in that, In step S3, the shear emulsification process is as follows: the molten lipid matrix is ​​injected into the mixing system, and continuous shear emulsification is performed at a shear rate of not less than 8000 rpm, and the final pH value of the system is adjusted and locked between 6.20 and 6.

40.

6. The preparation process of the meat-flavored paste flavoring based on optimized aroma properties according to claim 1, characterized in that, In step S4, before the isothermal thermal reaction under the pressurized conditions, an induced pre-condensation stage is also included: the system temperature is raised to 95°C to 105°C under normal pressure boiling conditions and maintained for 30 to 50 minutes. The process of constant temperature thermal reaction under pressurization is as follows: the pipeline connected to the atmosphere is sealed to make the reaction system airtight, the temperature is forcibly increased to the core temperature of the system to 120°C to 130°C, the surface pressure inside the system to 0.10 MPa to 0.18 MPa, and the reaction is carried out under constant temperature and pressure for 45 minutes to 75 minutes.

7. The preparation process of the meat-flavored paste flavoring based on optimized aroma properties according to claim 1, characterized in that, In step S5, the transient flash evaporation depressurization process is as follows: the high-pressure sealed reactor is connected to a vacuum buffer tank that has been pre-evacuated to an absolute pressure not exceeding 10 kPa for depressurization. The effective volume of the vacuum buffer tank is not less than 3 times the effective volume of the sealed reactor, so that the absolute pressure of the system drops to 35 kPa to 45 kPa within 3 to 5 minutes. The latent heat is absorbed by the boiling vaporization of water under low pressure, so that the core temperature of the material drops to below 80°C. The process of isothermal dehydration and concentration under vacuum and low pressure conditions is as follows: continuous vacuuming is used to maintain the absolute pressure of the system at 20.0 kPa to 30.0 kPa, and a compensating heat source is provided to the jacket to maintain the core temperature of the material at 60°C to 65°C for low-pressure water vaporization and separation.

8. The preparation process of the meat-flavored paste flavoring based on optimized aroma properties according to claim 7, characterized in that, The process of constant temperature dehydration and concentration under vacuum and low pressure also includes the step of adding rheology modifiers: when the concentration is carried out to the point that the material is in a thick paste state, the hydrated and swollen xanthan gum is drawn in under vacuum negative pressure for vacuum mixing. The endpoint determination criteria for the isothermal dehydration and concentration are: the free water content of the material monitored online drops to 22.0% to 25.0%, and the water activity drops to below 0.

75.

9. The preparation process of the meat-flavored paste flavoring based on optimized aroma properties according to claim 1, characterized in that, After step S5, a post-processing step is also included: after dehydration and concentration are completed and the vacuum is released, when the temperature of the material in the reactor drops below 65°C, disodium ribonucleotide is added and stirred and mixed evenly in the reactor; then the paste material is pumped into a forced cooling heat exchanger and cooled to 35°C to 40°C in a closed pipeline. After the particles are filtered out by a mesh filter, the material is sealed and filled under nitrogen purging conditions.

10. A meat-flavored paste flavoring with optimized aroma properties and its preparation process, characterized in that, The meat-flavored paste flavoring is prepared by any one of the preparation processes according to claims 1 to 9.