Quality improving and flavor enhancing process of sauce marinated meat by synergistic deoiling of composite spices

Abstract

The application relates to the technical field of meat processing, and discloses a sauce marinated meat quality improving and flavor enhancing process with composite spices and synergistic oil removal, which comprises the following steps: preparing pretreated meat blocks, spices, glycyrrhiza extract and hawthorn extract, preparing a gas float agent aqueous solution and a quenching agent aqueous solution; mixing water in proportion and constant-temperature boiling, establishing a weak-acid emulsification system to promote fat dissolution; injecting the gas float agent into the system, in-situ releasing carbon dioxide micro-bubbles by neutralizing sodium bicarbonate and organic acid, adsorbing fat and driving the fat to float up; subsequently injecting the 0-4 DEG C quenching agent aqueous solution containing calcium chloride, destroying the emulsion stability to promote free fat demulsification and fusion, and at the same time, the meat blocks are physically shrunk by cold, and the fat-soluble flavor molecules infiltrated are intercepted in the texture; and finally, separating the floating oil by standing. Through the synergistic effect of in-situ gas floatation and cold shrinkage mechanism, the application realizes mild and efficient oil removal, effectively alleviates the problem of aroma substance loss along with oil, and reduces the greasy feeling of the finished product.

Description

Technical Field

[0001] This invention relates to the field of meat processing technology, specifically to a process for enhancing the quality and aroma of braised meat through the synergistic degreasing of compound spices. Background Technology

[0002] Braised meat is a traditional cooked meat product, typically made from pork, chicken, or other meats, simmered for a long time at a constant temperature with various spices and seasonings. During the simmering process, subcutaneous and intramuscular fat in the meat is released into the braising liquid. With increasing consumer demand for healthy eating, reducing the fat content and greasiness of finished braised meat has become an important processing requirement.

[0003] Currently, conventional processing methods mostly rely on natural settling and skimming or mechanical centrifugation to remove oil during the later stages of cooking. However, in actual cooking environments, the free fat dissolved from the meat easily interacts with water, dissolved meat proteins, and seasonings in the system, forming a thermodynamically stable oil-in-water emulsion system under prolonged heating. This emulsification phenomenon makes simple settling and separation time-consuming and insufficiently thorough; while frequent mechanical scooping or forced physical degreasing can easily cause disturbance to the liquid surface, leading to secondary mixing of oil and water and reducing separation efficiency.

[0004] On the other hand, the characteristic flavor of braised meat mainly comes from fat-soluble flavor compounds released from spices. These aroma molecules tend to dissolve and accumulate in the free fat phase during the cooking process. When skimming and removing fat are intensified during processing to reduce greasiness, a large amount of flavor compounds attached to the oil are also expelled from the system. This processing method, while removing fat, strips away the fat-soluble aromas that the meat should absorb, resulting in a final product that often faces the dilemma of flavor loss and bland taste, making it difficult to achieve a balance between removing fat and retaining a rich braised aroma. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a compound spice synergistic degreasing process for enhancing the quality and aroma of braised meat. This process solves the problem that during the traditional braising process, the free fat dissolved from the meat matrix easily forms a thermodynamically stable oil-in-water emulsion with water, protein, and seasonings in the system. This results in long separation times and low degreasing efficiency. Furthermore, during enhanced degreasing, fat-soluble flavor substances are easily separated from the meat matrix, leading to a greasy final product and loss of some aroma.

[0006] In a first aspect, the present invention provides a process for enhancing the quality and aroma of braised meat through synergistic degreasing of compound spices, employing the following technical solution: A process for enhancing the quality and aroma of braised meat through synergistic degreasing with compound spices includes the following steps: S1. Preparation of materials: Based on 100 parts by weight of total water, prepare pre-treated meat chunks, seasonings, 0.5-1.0 parts of spice powder, 0.1-0.2 parts of licorice extract, and 0.3-0.5 parts of hawthorn extract containing 20%-30% total organic acids; prepare an aqueous solution of chilling agent containing 0.05-0.08 parts of anhydrous calcium chloride at a temperature of 0-4°C; prepare an aqueous solution of flotation agent according to the citric acid equivalent molar ratio of sodium bicarbonate to the total organic acids being 0.75:1-0.85:1. S2. Cooking: Add the remaining water (excluding the water used for preparation) and the above dry materials to the reaction vessel, and add the meat chunks at 82-85℃ and a stirring speed of 30-50 r / min and cook for 60-90 min. S3, Air flotation: Maintain the temperature and rotation speed, inject the air flotation agent aqueous solution into the reactor, and react for 1.0 to 1.5 minutes; S4. Demulsification: Stop heating and turn on cooling. Inject the quenching agent aqueous solution into the reactor. Reduce the stirring speed to 10-15 r / min and maintain it for 4-6 min until the system temperature drops to 65-68℃. S5. Separation: Stop stirring, let stand for 3-5 minutes to form an oil layer, separate the oil layer and discharge the material.

[0007] By adopting the above technical solution, this process uses a combination of air flotation degreasing and physical shrinkage to process meat pieces. The specific reaction and change process it undergoes is described below: Specifically, during the constant-temperature cooking stage of S2, the hawthorn extract added to the system provides organic acids, making the aqueous phase in the reactor slightly acidic. This acidic environment is relatively conducive to the swelling of collagen in the meat chunks, thereby promoting the dissolution of internal fat. During this period, the glycyrrhizic acid contained in the licorice extract has surface activity, which can encapsulate the dissolved fat, forming an oil-in-water emulsion; at the same time, the fat-soluble flavor molecules in the spices also dissolve in this fat phase.

[0008] Subsequently, in the in-situ flotation stage of S3, sodium bicarbonate in the injected flotation agent aqueous solution encounters the organic acid in the system, and the two undergo a neutralization reaction, releasing carbon dioxide gas. Taking citric acid, a major component of the organic acid, as an example, the reaction equation is typically as follows: 3NaHCO3+C6H8O7→C6H5O7Na3+3H2O+3CO2↑; The reaction directly generates a large number of carbon dioxide microbubbles inside the liquid phase of the reactor. As these bubbles rise, they adsorb fat droplets and some suspended protein flocculants from the oil-in-water emulsion, thereby relatively reducing the apparent density of the fat droplets and forming gas-liquid-solid aggregates that carry the fat to the surface. Setting the molar ratio of sodium bicarbonate to total organic acids in the range of 0.75:1 to 0.85:1 is primarily to maintain a slightly acidic state in the system after the reaction, which typically avoids the degradation of meat proteins or the generation of off-flavors due to excessive alkalization.

[0009] In the S4 demulsification stage, after the injection of anhydrous calcium chloride aqueous solution at 0–4°C, the overall temperature of the system decreases, and the thermodynamic stability of the emulsion phase weakens. During this process, calcium ions ionized from calcium chloride readily complex with glycyrrhizic acid or free fatty acids at the emulsion interface, forming insoluble calcium salts. This disrupts the tension state of the emulsion interface and promotes the demulsification of free fat, allowing the scattered fat to fuse together and form a continuous oil layer. It is also worth noting that the muscle fibers and collagen on the surface of the meat are prone to cold contraction when faced with a sudden drop in temperature and the action of calcium ions, causing some of the original pores inside to close. This, to some extent, traps the spice flavor molecules that have previously penetrated into the meat within the meat texture, reducing the amount of flavor molecules that float to the surface with the fat and detach from the meat.

[0010] Preferably, in S1, the spice powder containing fat-soluble aroma components is composed of star anise powder, clove powder and cinnamon powder, and the mass ratio of star anise powder, clove powder and cinnamon powder is 2:1:1.

[0011] By adopting the above technical solution, star anise, cloves and cinnamon are mixed in this fixed mass ratio. The phenolic and terpenoid substances they provide usually have a good tendency for fat-soluble distribution in a weakly acidic emulsion system, which helps to increase the concentration of flavor substances that ultimately remain inside the meat texture.

[0012] Preferably, in S1, the amount of water used to prepare the chilling demulsifier is 15.0 to 20.0 parts.

[0013] By adopting the above technical solution and limiting the amount of water used in the preparation, it is ensured that when this part of the solution is injected into the system, the sensible heat in the reactor is absorbed by the specific heat capacity of water, which can basically meet the physical cooling requirement of reducing the homogeneous temperature of the system to 65-68℃ within 4-6 minutes.

[0014] Preferably, in step S3, the air flotation trigger agent is injected into the reactor within 15-20 seconds using a feeding pump; in step S4, the chilling demulsifier is injected into the reactor within 20-30 seconds using a delivery pump.

[0015] By adopting the above technical solution, the flotation trigger agent is pumped in within 15 to 20 seconds, which can limit the diffusion rate of sodium bicarbonate to a certain extent, making the generation of microbubble clusters relatively stable, thereby reducing the possibility of liquid surface turbulence and overflow caused by a sudden large amount of gas production; while the chilling demulsifier is pumped in within 20 to 30 seconds, mainly to alleviate the problem of complexed calcium salt agglomeration and deposition caused by a sudden increase in local calcium ion concentration.

[0016] Preferably, S5 is implemented as follows: the overflow weir at the top of the reactor is opened to discharge the surface oil and solid residue carried by the liquid to the waste oil system; the bottom valve of the reactor is opened to discharge the liquid and meat chunks.

[0017] By adopting the above technical solution, the oil phase and water-solid phase are separated by the height difference of physical spatial location, thereby reducing the secondary mixing of oil and water caused by mechanical agitation when using traditional salvage tools.

[0018] Preferably, in S1, the meat chunks are pork belly chunks or chicken leg chunks with skin.

[0019] By adopting the above technical solution, pork belly chunks and skin-on chicken leg chunks contain abundant subcutaneous fat and intramuscular fat, and under this process condition, there is corresponding room for degreasing.

[0020] Preferably, the licorice extract powder in S1 is prepared by the following steps: After pulverizing the rhizome of Glycyrrhiza glabra, add 6 to 10 times its weight of an ammonia solution with a mass fraction of 0.3 to 0.8%, and extract countercurrently at 75 to 85°C for 1.5 to 2.5 hours to obtain an extract. After centrifugation, take the supernatant and pass it through an ultrafiltration membrane with a molecular weight cutoff of 3000 Da to remove macromolecular impurities. Collect the filtrate and concentrate it under reduced pressure to a relative density of 1.15 to 1.25, and then spray dry to obtain the licorice extract powder.

[0021] By employing the above-mentioned technical solution and using weakly alkaline ammonia water as the extraction solvent, it is beneficial to promote the conversion of free glycyrrhizic acid in *Glycyrrhiza glabra* into glycyrrhizic acid monoammonium salt, thereby increasing the solubility and surface activity of glycyrrhizic acid in the aqueous phase. The extract is then treated with an ultrafiltration membrane with a molecular weight cutoff of 3000 Da to retain large molecular weight proteins and some polysaccharides. Reducing these large molecular substances can lower the probability of Maillard reactions or caramelization and coking of large organic molecules on the heated surface of the reactor during subsequent boiling, keeping the boiling liquid at a relatively low viscosity, thus providing better fluid conditions for the rise of bubbles in the air flotation stage.

[0022] Preferably, the glycyrrhizic acid content in the licorice extract powder is 60-70% by mass; in the preparation step, the centrifugation speed is 4000 r / min and the time is 15 min; the inlet air temperature of the spray drying is 150-170℃ and the outlet air temperature is 75-85℃.

[0023] By adopting the above technical solution, the resulting licorice extract powder contains a sufficient amount of glycyrrhizic acid monoammonium salt to maintain the oil-water emulsion interface. Setting the inlet and outlet air temperatures for this spray drying process relatively reduces the probability of the extract undergoing deammoniation reaction upon heating, thus maintaining the physicochemical stability of the powder.

[0024] Preferably, the hawthorn extract powder in S1 is prepared by the following steps: After pulverizing dried hawthorn fruit, add 8-12 times its weight of a 50-70% ethanol aqueous solution and perform ultrasonic-assisted reflux extraction at 50-70℃ for 1.0-2.0 h. After filtration, the extract is subjected to vacuum distillation to recover the ethanol, yielding an aqueous extract. The aqueous extract is then passed through a chromatography column packed with a hydrogen-type D001 macroporous strong acid styrene-based cation exchange resin for desalting and release. The unadsorbed eluent and the pure water eluent are collected, combined, and concentrated under reduced pressure. Subsequently, the mixture is freeze-dried at -40℃ to obtain the hawthorn extract powder.

[0025] By employing the above-mentioned technical solution, the ethanol-water solution disrupts the cell walls of hawthorn to leach organic acids. When the aqueous extract passes through a hydrogen-form D001 cation exchange resin, the hydrogen ions on the resin displace and adsorb the endogenous metal cations in the extract, causing the organic acid salts to dissociate into free organic acids. This removal of metal cations is primarily to reduce the risk of inorganic ash consuming sodium bicarbonate during the flotation stage, making the molar ratio of sodium bicarbonate to the subsequent neutralization reaction of total organic acids easier to control. Freeze-drying at -40℃ is used mainly to avoid the dehydration condensation stage that conventional high-temperature drying easily causes in heat-sensitive organic acids.

[0026] Preferably, in the preparation step, the flow rate of the aqueous extract through the chromatography column is 2 BV / h, and the volume of the collected pure water eluent is 2 BV.

[0027] By adopting the above technical solution, controlling the liquid flow rate to 2 BV / h facilitates sufficient exchange between the metal cations in the extract and the sulfonic acid groups on the resin. Using an elution volume of 2 BV generally allows for better elution of free organic acids physically retained in the resin interstices, thereby improving the overall yield of organic acids.

[0028] This invention provides a process for enhancing the quality and aroma of braised meat through synergistic degreasing with compound spices. It offers the following beneficial effects: 1. This invention utilizes the neutralization of organic acids provided by sodium bicarbonate and hawthorn extract within the reaction system to generate carbon dioxide microbubbles in situ. As these bubbles rise in the liquid phase, they adsorb fat droplets and drive them to aggregate towards the liquid surface. This in-situ flotation treatment method reduces reliance on mechanical stirring and manual removal, minimizing manual agitation during oil-water separation and thus relatively improving the removal and separation efficiency of free fats.

[0029] 2. This invention introduces a calcium chloride aqueous solution at 0-4°C during the demulsification stage. The cooling of the system itself reduces the thermal stability of the emulsion, and combined with the complexation reaction between calcium ions and interfacial free acids, accelerates the demulsification and fusion process of free fats. On the other hand, when the meat chunks are exposed to localized low temperatures and calcium ion stimulation, they undergo a certain degree of physical shrinkage, and the surface pores tend to close, trapping the fat-soluble spice flavor molecules that have previously penetrated the meat chunks. This, to some extent, preserves the internal aroma of the meat product and alleviates the problem of flavor substances easily being lost with the oil during fortified degreasing.

[0030] 3. This invention adds corresponding physical impurity removal pretreatment steps for licorice and hawthorn extract raw materials. Ultrafiltration removes large molecular weight proteins from the licorice extract, reducing surface scorching during boiling and maintaining a relatively low viscosity of the liquid phase. The hawthorn extract undergoes cation exchange resin treatment to remove endogenous metal cations, reducing the unnecessary consumption of sodium bicarbonate by inorganic impurities during the flotation stage. These two pretreatment features work together to ensure a more accurate acid-base ratio during the subsequent flotation reaction, which helps maintain the consistency of the oil removal process across different batches. Detailed Implementation

[0031] The main raw materials and reagents used in the following examples and comparative examples have the following sources and specifications. Reagents not specifically mentioned are all commercially available analytical grade or higher grade products.

[0032] The meat matrix used in this invention consists of commercially available fresh pork belly and commercially available skin-on chicken thigh meat; wherein pork belly was used in Examples 1-3 and each comparative example, and skin-on chicken thigh meat was used in Example 4. The spice powders containing fat-soluble aroma components are commercially available star anise powder, clove powder, and cinnamon powder, all with a particle size of 60 to 80 mesh.

[0033] The plant substrates used to prepare the specific functional extract were commercially available licorice root and rhizome powder and hawthorn dried fruit powder. The core active component extracted from the licorice root and rhizome powder was glycyrrhizic acid (molecular formula C10). 42 H 62 O 16 CAS: 1405-86-3.

[0034] The D001 type macroporous strong acid styrene-based cation exchange resin used in the extraction and purification process is a commercially available, conventional product. The anhydrous calcium chloride used in the process stage to prepare the chilling demulsifier has a purity ≥96.0% (molecular formula CaCl2, CAS: 10043-52-4). The sodium bicarbonate used in the process stage to prepare the in-situ air flotation trigger has a purity ≥99.5% (molecular formula NaHCO3, CAS: 144-55-8).

[0035] Preparation Example 1: This preparation example provides a method for preparing licorice extract, including the following steps: (1) Extraction: After crushing the root and rhizome of Glycyrrhiza glabra, add 8 times its mass of ammonia solution with a mass fraction of 0.5% and extract countercurrently at 80℃ for 2 hours.

[0036] (2) Centrifugation and ultrafiltration: After centrifuging the extract at 4000 r / min for 15 min, the supernatant was taken and ultrafiltered through an ultrafiltration membrane with a molecular weight cutoff of 3000 Da to remove macromolecular impurities.

[0037] (3) Concentration and drying: The filtrate was collected and concentrated under reduced pressure to a relative density of 1.20, followed by spray drying. The inlet air temperature was controlled at 160℃ and the outlet air temperature at 80℃ to obtain licorice extract powder. The glycyrrhizic acid (C1) content in the powder was determined. 42 H 62 O 16 The mass fraction of ( ) is 65%.

[0038] Preparation Example 2: This preparation example provides a method for preparing licorice extract, including the following steps: (1) Extraction: After crushing the root and stem of Glycyrrhiza glabra, add 6 times its mass of ammonia solution with a mass fraction of 0.3% and extract countercurrently at 75℃ for 1.5h.

[0039] (2) Centrifugation and ultrafiltration: After centrifuging the extract at 4000 r / min for 15 min, the supernatant was taken and ultrafiltered through an ultrafiltration membrane with a molecular weight cutoff of 3000 Da to remove macromolecular impurities.

[0040] (3) Concentration and drying: The filtrate was collected and concentrated under reduced pressure to a relative density of 1.15, followed by spray drying. The inlet air temperature was controlled at 150℃ and the outlet air temperature at 75℃ to obtain licorice extract powder. The glycyrrhizic acid (C1) content in the powder was determined. 42 H 62 O 16 The mass fraction of ) is 60%.

[0041] Preparation Example 3: This preparation example provides a method for preparing licorice extract, including the following steps: (1) Extraction: After crushing the root and rhizome of Glycyrrhiza glabra, add 10 times its weight of ammonia solution with a mass fraction of 0.8% and extract countercurrently at 85℃ for 2.5h.

[0042] (2) Centrifugation and ultrafiltration: After centrifuging the extract at 4000 r / min for 15 min, the supernatant was taken and ultrafiltered through an ultrafiltration membrane with a molecular weight cutoff of 3000 Da to remove macromolecular impurities.

[0043] (3) Concentration and drying: The filtrate was collected and concentrated under reduced pressure to a relative density of 1.25, followed by spray drying. The inlet air temperature was controlled at 170℃ and the outlet air temperature at 85℃ to obtain licorice extract powder. The glycyrrhizic acid (C1) content in the powder was determined. 42 H 62 O 16 The mass fraction of ( ) is 70%.

[0044] Preparation Example 4: This preparation example provides a method for preparing hawthorn extract, including the following steps: (1) Extraction: After crushing the dried hawthorn fruit, add 10 times its weight of 60% ethanol aqueous solution and perform ultrasonic-assisted reflux extraction at 60℃ for 1.5h.

[0045] (2) Ethanol recovery and desalting: After filtration, the extract was subjected to vacuum distillation to recover ethanol, resulting in an aqueous extract. The aqueous extract was then passed through a chromatography column packed with a hydrogen-type D001 macroporous strong acid styrene-based cation exchange resin at a flow rate of 2 BV / h for desalting. The unadsorbed eluent and 2 BV of pure water eluent were collected.

[0046] (3) Concentration and freeze-drying: The collected liquids were combined and concentrated under reduced pressure, and then freeze-dried at -40℃ for 48 hours to obtain hawthorn extract powder. The mass fraction of total organic acids in the powder was determined to be 25%.

[0047] Preparation Example 5: This preparation example provides a method for preparing hawthorn extract, including the following steps: (1) Extraction: After crushing the dried hawthorn fruit, add 8 times its weight of 50% ethanol aqueous solution and perform ultrasonic-assisted reflux extraction at 50℃ for 1.0h.

[0048] (2) Ethanol recovery and desalting: After filtration, the extract was subjected to vacuum distillation to recover ethanol, resulting in an aqueous extract. The aqueous extract was then passed through a chromatography column packed with a hydrogen-type D001 macroporous strong acid styrene-based cation exchange resin at a flow rate of 2 BV / h for desalting. The unadsorbed eluent and 2 BV of pure water eluent were collected.

[0049] (3) Concentration and freeze-drying: The collected liquids were combined and concentrated under reduced pressure, and then freeze-dried at -40℃ for 48 hours to obtain hawthorn extract powder. The mass fraction of total organic acids in the powder was determined to be 20%.

[0050] Preparation Example 6: This preparation example provides a method for preparing hawthorn extract, including the following steps: (1) Extraction: After crushing the dried hawthorn fruit, add 12 times its weight of 70% ethanol aqueous solution and perform ultrasonic-assisted reflux extraction at 70℃ for 2.0h.

[0051] (2) Ethanol recovery and desalting: After filtration, the extract was subjected to vacuum distillation to recover ethanol, resulting in an aqueous extract. The aqueous extract was then passed through a chromatography column packed with a hydrogen-type D001 macroporous strong acid styrene-based cation exchange resin at a flow rate of 2 BV / h for desalting. The unadsorbed eluent and 2 BV of pure water eluent were collected.

[0052] (3) Concentration and freeze-drying: The collected liquids were combined and concentrated under reduced pressure, and then freeze-dried at -40℃ for 48 hours to obtain hawthorn extract powder. The mass fraction of total organic acids in the powder was determined to be 30%. Example 1:

[0053] This embodiment provides a process for enhancing the quality and aroma of braised meat through synergistic degreasing with compound spices. The total amount of water used in the process is set at 100 kg, and the process includes the following steps: (1) Raw material preparation: Prepare basic seasonings and pre-treated pork belly chunks. Weigh 0.75 kg of spice powder containing fat-soluble aroma components (star anise powder, clove powder, and cinnamon powder in a mass ratio of 2:1:1), 0.15 kg of licorice extract powder prepared in Preparation Example 1, and 0.4 kg of hawthorn extract powder prepared in Preparation Example 4. Dissolve 0.065 kg of anhydrous calcium chloride completely in 17.5 kg of purified water. After the dissolution and exothermic reaction are completed, cool the resulting calcium chloride aqueous solution and keep it at 2°C. Place it in a thermos as a quenching demulsifier for later use. It is known that the total organic acid content in 0.4 kg of hawthorn extract powder prepared in Example 4 is 100 g, which is approximately 0.52 mol in citric acid equivalent. Based on a molar ratio of sodium bicarbonate to citric acid equivalent of 0.8:1, 35.0 g of sodium bicarbonate with a purity ≥99.5% is weighed out. A small amount of room temperature water is reserved from the 82.5 kg of room temperature purified water mentioned in step (2) to dissolve the sodium bicarbonate and prepare a flotation trigger agent for later use. The above amount of sodium bicarbonate is prepared in insufficient quantities based on the molar amount of anhydrous citric acid after conversion of the total organic acid, not according to the acid-base equivalent required for complete neutralization of citric acid, to avoid excessive alkalization of the system and ensure in-situ gas release effect.

[0054] (2) Constant temperature cooking: In a standard reactor equipped with a variable frequency stirrer and a jacket, add the remaining portion of the 82.5 kg of room temperature purified water from step (1) after deducting the water used to prepare the air flotation trigger, the basic seasonings, and the spice powder containing fat-soluble aroma components, licorice extract powder, and hawthorn extract powder prepared above. Turn on the jacket steam to keep the system temperature constant at 85℃. Add the pork belly pieces, turn on the stirrer, set the speed to 40 r / min, and maintain constant temperature cooking for 75 min.

[0055] (3) In-situ air flotation trigger: When the countdown of step (2) ends, maintain the system temperature at 85°C and the stirring speed at 40 r / min. Inject the prepared air flotation trigger agent (sodium bicarbonate aqueous solution) into the high turbulence zone of the fluid at the bottom of the reactor through a high-pressure feed pump within 15s, and continue the reaction for 1.2min while maintaining the original state.

[0056] (4) Rapid cooling demulsification: After the gas release time in step (3) is reached, immediately shut off the jacket steam valve. Start the high-flow-rate pump and inject the prepared rapid cooling demulsifier (a low-temperature aqueous solution containing calcium chloride at 2°C) from the heat preservation tank into the reactor within 25 seconds. At the same time, fully open the jacket cooling water valve. Quickly reduce the speed of the variable frequency stirrer to 12 r / min and maintain it for 5 minutes until the homogeneous temperature of the system drops to 66°C.

[0057] (5) Static separation and discharge: Turn off the agitator and allow the homogeneous system to settle completely for 4 minutes, forming a floating oil layer on the liquid surface. Open the overflow weir at the top of the reactor to separate the surface floating oil and the solid residue it carries and discharge it to the waste oil system. Finally, open the bottom valve of the reactor to discharge the liquid and the de-oiled and flavored pork belly. Example 2:

[0058] This embodiment provides a process for enhancing the quality and aroma of braised meat through synergistic degreasing with compound spices. The total amount of water used in the process is set at 100 kg, and the process includes the following steps: (1) Raw material preparation: Prepare basic seasonings and pre-treated pork belly chunks. Weigh 0.5 kg of spice powder containing fat-soluble aroma components (star anise powder, clove powder, and cinnamon powder in a mass ratio of 2:1:1), 0.1 kg of licorice extract powder prepared in Preparation Example 2, and 0.3 kg of hawthorn extract powder prepared in Preparation Example 5. Dissolve 0.05 kg of anhydrous calcium chloride completely in 15.0 kg of purified water. After the dissolution and exothermic reaction are completed, cool the resulting calcium chloride aqueous solution and keep it at 4°C. Place it in a thermos as a quenching and demulsifying agent for later use. Given that the total organic acid content in 0.3 kg of hawthorn extract powder prepared in Example 5 is 60 g, which is approximately 0.31 mol in citric acid equivalent, and considering the molar ratio of sodium bicarbonate to citric acid equivalent in total organic acid is 0.75:1, 19.7 g of sodium bicarbonate with a purity ≥99.5% is weighed out. A small amount of room temperature water is reserved from the 85.0 kg of room temperature purified water mentioned in step (2) to dissolve the sodium bicarbonate and prepare an air flotation trigger agent for later use. The metering diameter of the water used to prepare the air flotation trigger agent is the same as in Example 1.

[0059] (2) Constant temperature cooking: In a standard reactor equipped with a frequency converter and a jacket, add the remaining portion of the 85.0 kg of room temperature purified water from step (1) after deducting the water used to prepare the flotation trigger, the basic seasonings, and the spice powder containing fat-soluble aroma components, licorice extract powder, and hawthorn extract powder prepared above. Turn on the jacket steam to keep the system temperature constant at 82℃. Add the pork belly pieces, turn on the stirrer, set the speed to 30 r / min, and maintain constant temperature cooking for 60 min.

[0060] (3) In-situ air flotation trigger: When the countdown of step (2) ends, maintain the system temperature at 82°C and the stirring speed at 30 r / min. Inject the prepared air flotation trigger agent (sodium bicarbonate aqueous solution) into the high turbulence zone of the fluid at the bottom of the reactor within 15s using a high-pressure feed pump, and continue the reaction for 1.0 min while maintaining the original state.

[0061] (4) Rapid cooling demulsification: After the gas release time in step (3) is reached, immediately shut off the jacket steam valve. Start the high-flow-rate pump and inject the prepared rapid cooling demulsifier (a low-temperature aqueous solution containing calcium chloride at 4°C) from the heat preservation tank into the reactor within 30 seconds. At the same time, fully open the jacket cooling water valve. Quickly reduce the speed of the variable frequency stirrer to 10 r / min and maintain it for 4 minutes until the homogeneous temperature of the system drops to 68°C.

[0062] (5) Static separation and discharge: Turn off the agitator and allow the homogeneous system to settle completely for 3 minutes, forming a floating oil layer on the liquid surface. Open the overflow weir at the top of the reactor to separate the surface floating oil and the solid residue it carries and discharge it to the waste oil system. Finally, open the bottom valve of the reactor to discharge the liquid and the de-oiled and flavored pork belly. Example 3:

[0063] This embodiment provides a process for enhancing the quality and aroma of braised meat through synergistic degreasing with compound spices. The total amount of water used in the process is set at 100 kg, and the process includes the following steps: (1) Raw material preparation: Prepare basic seasonings and pre-treated pork belly chunks. Weigh 1.0 kg of spice powder containing fat-soluble aroma components (star anise powder, clove powder, and cinnamon powder in a mass ratio of 2:1:1), 0.2 kg of licorice extract powder prepared in Preparation Example 3, and 0.5 kg of hawthorn extract powder prepared in Preparation Example 6. Dissolve 0.08 kg of anhydrous calcium chloride completely in 20.0 kg of purified water. After the dissolution and exothermic reaction are complete, cool the resulting calcium chloride aqueous solution and keep it at 0°C to 2°C, allowing a small amount of tiny ice crystals to exist in the system. Place it in a thermos as a quenching and demulsifying agent for later use. Given that the total organic acid content in 0.5 kg of hawthorn extract powder prepared in Example 6 is 150 g, which is approximately 0.78 mol in citric acid equivalent, and considering the molar ratio of sodium bicarbonate to citric acid equivalent of total organic acid is 0.85:1, weigh out 55.8 g of sodium bicarbonate with a purity ≥99.5%. Reserve a small amount of room temperature water from the 80.0 kg of room temperature purified water mentioned in step (2) to dissolve the sodium bicarbonate and prepare an air flotation trigger agent for later use. The metering of water used for preparing the air flotation trigger agent is the same as in Example 1.

[0064] (2) Constant temperature cooking: In a standard reactor equipped with a frequency converter and a jacket, add the remaining portion of the 80.0 kg of room temperature purified water from step (1) after deducting the water used to prepare the flotation trigger, the basic seasonings, and the spice powder containing fat-soluble aroma components, licorice extract powder, and hawthorn extract powder prepared above. Turn on the jacket steam to keep the system temperature constant at 85℃. Add the pork belly pieces, turn on the stirrer, set the speed to 50 r / min, and maintain constant temperature cooking for 90 min.

[0065] (3) In-situ air flotation trigger: When the countdown of step (2) ends, maintain the system temperature at 85°C and the stirring speed at 50 r / min. Inject the prepared air flotation trigger agent (sodium bicarbonate aqueous solution) into the high turbulence zone of the fluid at the bottom of the reactor through a high-pressure feed pump within 20s, and continue the reaction for 1.5min while maintaining the original state.

[0066] (4) Rapid cooling demulsification: After the gas release time in step (3) is reached, immediately shut off the jacket steam valve. Start the high-flow-rate pump and inject the prepared rapid cooling demulsifier (a low-temperature aqueous solution or ice-water mixture containing calcium chloride at 0℃ to 2℃) from the heat preservation tank into the reactor within 20 seconds. At the same time, fully open the jacket cooling water valve. Quickly reduce the speed of the variable frequency stirrer to 15 r / min and maintain it for 6 min until the homogeneous temperature of the system drops to 65℃.

[0067] (5) Static separation and discharge: Turn off the agitator and allow the homogeneous system to settle completely for 5 minutes, forming a floating oil layer on the liquid surface. Open the overflow weir at the top of the reactor to separate the surface floating oil and the solid residue it carries and discharge it to the waste oil system. Finally, open the bottom valve of the reactor to discharge the liquid and the de-oiled and flavored pork belly. Example 4:

[0068] This embodiment provides a process for enhancing the quality and aroma of braised meat through synergistic degreasing with compound spices. The total amount of water used in the process is set at 100 kg, and the process includes the following steps: (1) Raw material preparation: Prepare basic seasonings and pre-treated chicken leg meat pieces with skin. Weigh 0.75 kg of spice powder containing fat-soluble aroma components (star anise powder, clove powder, and cinnamon powder in a mass ratio of 2:1:1), 0.15 kg of licorice extract powder prepared in Preparation Example 1, and 0.4 kg of hawthorn extract powder prepared in Preparation Example 4. Dissolve 0.065 kg of anhydrous calcium chloride completely in 17.5 kg of purified water. After the dissolution and exothermic reaction are completed, cool the resulting calcium chloride aqueous solution and keep it at 2°C. Place it in a thermos as a quenching and demulsifying agent for later use. Given that the total organic acid content in 0.4 kg of hawthorn extract powder prepared in Example 4 is 100 g, which is approximately 0.52 mol in citric acid equivalent, and considering the molar ratio of sodium bicarbonate to citric acid equivalent of total organic acid is 0.8:1, weigh out 35.0 g of sodium bicarbonate with a purity ≥99.5%. Reserve a small amount of room temperature water from the 82.5 kg of room temperature purified water mentioned in step (2) to dissolve the sodium bicarbonate and prepare an air flotation trigger agent for later use. The metering of water used for preparing the air flotation trigger agent is the same as in Example 1.

[0069] (2) Constant temperature cooking: In a standard reactor equipped with a frequency converter and a jacket, add the remaining portion of the 82.5 kg of room temperature purified water from step (1) after deducting the water used to prepare the flotation trigger, the basic seasonings, and the spice powder containing fat-soluble aroma components, licorice extract powder, and hawthorn extract powder prepared above. Turn on the jacket steam to keep the system temperature constant at 85℃. Add the chicken leg pieces with skin, turn on the stirrer, set the speed to 40 r / min, and maintain constant temperature cooking for 75 min.

[0070] (3) In-situ air flotation trigger: When the countdown of step (2) ends, maintain the system temperature at 85°C and the stirring speed at 40 r / min. Inject the prepared air flotation trigger agent (sodium bicarbonate aqueous solution) into the high turbulence zone of the fluid at the bottom of the reactor through a high-pressure feed pump within 15s, and continue the reaction for 1.2min while maintaining the original state.

[0071] (4) Rapid cooling demulsification: After the gas release time in step (3) is reached, immediately shut off the jacket steam valve. Start the high-flow-rate pump and inject the prepared rapid cooling demulsifier (a low-temperature aqueous solution containing calcium chloride at 2°C) from the heat preservation tank into the reactor within 25 seconds. At the same time, fully open the jacket cooling water valve. Quickly reduce the speed of the variable frequency stirrer to 12 r / min and maintain it for 5 minutes until the homogeneous temperature of the system drops to 66°C.

[0072] (5) Static separation and discharge: Turn off the agitator and allow the homogeneous system to settle completely for 4 minutes, forming a floating oil layer on the liquid surface. Open the overflow weir at the top of the reactor to separate the surface floating oil and the solid residue it carries and discharge it to the waste oil system. Finally, open the bottom valve of the reactor to discharge the liquid and the skin-on chicken leg meat after degreasing and flavoring.

[0073] Comparative Example 1: Compared with Example 1, the differences are as follows: a traditional high-temperature long-time cooking process was adopted, and licorice extract powder and hawthorn extract powder were not added to the raw material formula; step two (sodium bicarbonate aqueous solution was not injected) was not performed; step three (low-temperature quenching demulsifier containing calcium chloride was not injected, and jacket cooling was not activated) was not performed; in order to maintain the comparability of the total amount of water phase, 100 kg of pure water was added at once in step one, and the cooking temperature in step one was set to 95°C, and the cooking time was extended to 120 min. Then the machine was stopped directly and allowed to stand to skim off the oil. The amount of other basic seasonings and spice powders containing fat-soluble aroma components added was the same.

[0074] Comparative Example 2: Compared with Example 1, the difference is that licorice extract powder and hawthorn extract powder were not added to the raw material formula, but sodium bicarbonate aqueous solution and calcium chloride-containing chilling demulsifier were added in the same mass as in Example 1 to investigate the deoiling and separation effect when the glycyrrhizic acid weak emulsification system and hawthorn organic acid gas-releasing substrate were missing. All other aspects are the same.

[0075] Comparative Example 3: Compared with Example 1, the difference is that no flotation trigger agent was prepared or added in the raw material preparation and process steps (that is, no sodium bicarbonate aqueous solution was injected in step 2, and the reaction was only stirred in the original state), and the rest were the same.

[0076] Comparative Example 4: Compared with Example 1, the difference is that in the raw material preparation and step three, a 2°C low-temperature aqueous solution is not used as the low-temperature carrier for the quenching demulsifier. Instead, 0.065 kg of anhydrous calcium chloride is completely dissolved in 17.5 kg of room temperature (about 25°C) pure water and injected into the reactor. The decrease in the homogeneous temperature of the system is achieved by direct contact heat exchange with room temperature water and jacket cooling. However, the quenching thermal shock conditions formed by the direct injection of the 2°C low-temperature quenching demulsifier are not present. All other aspects are the same.

[0077] Comparative Example 5: Compared with Example 1, the difference is that anhydrous calcium chloride was not added to the chilled demulsifier (i.e., only 17.5 kg of 2°C low-temperature pure water without any salts was injected in step three), and everything else is the same.

[0078] Comparative Example 6: Compared with Example 1, the difference is that the spatial and temporal logic of the addition of substances is disrupted. In the initial boiling stage of step one, sodium bicarbonate and anhydrous calcium chloride, along with licorice extract powder and hawthorn extract powder, are all added to the reaction vessel at once. In step three, only 17.5 kg of 2°C low-temperature purified water is added, and the rest are the same.

[0079] Unless otherwise specified, the test items in each of the following test examples were performed in triplicate, and the data in the table are the arithmetic mean of the three test results.

[0080] Test Example 1: This test case is used to examine the changes in temperature, pH value and surface tension of the aqueous phase in the reactor system during the process operation of Example 1, so as to characterize the changes in key physicochemical parameters of maintaining the weak acid environment, in-situ gas release triggering and rapid cooling demulsification stage in the process of the present invention.

[0081] The specific testing method includes the following steps: (1) Setting up online monitoring devices: Before performing the process of Example 1, industrial thermocouples and online pH sensors with automatic temperature compensation function were installed in the fluid body area of ​​the jacketed standard reactor and connected to the data acquisition terminal. The sampling frequency of temperature and pH value was set to be once every 10 seconds, and the monitoring time continued until the end of step three of Example 1.

[0082] (2) Process operation and online data acquisition: The process steps and feeding ratio of Example 1 are executed sequentially, and the continuous changes of the homogeneous temperature and pH value of the system are recorded from the beginning of step one to the end of step three.

[0083] (3) Sampling and Surface Tension Measurement at Nodes: Sampling was performed at specific time points during the process. The sampling points were: at the beginning of step one (0 min); in the middle of step one (40 min); at the end of step one (75 min); at the end of step two (76.2 min); after the injection of the chilling demulsifier in step three (77 min); and at the end of step three (81.2 min). 50 mL of the aqueous phase mixture was drawn from the middle aqueous phase region of the reactor each time. After standing and venting for 5 seconds, the mixture was transferred to a constant temperature of 25℃ for testing. The surface tension of the aqueous phase was measured using a fully automatic surface tension meter based on the platinum plate method. Each sampling point was measured in triplicate, and the arithmetic mean was taken.

[0084] Based on the above monitoring process, test data for each key node were obtained, and the results are shown in Table 1.

[0085] Table 1. Dynamic monitoring data of key physicochemical parameters throughout the entire process of Example 1: 0 min (Initial stage of step one) 84.7 5.28 28.1 40 minutes (mid-run of step one) 85.2 5.34 27.6 75 minutes (at the end of step one) 84.9 5.31 27.4 76.2 min (at the end of step two) 85.1 6.45 29.2 77 min (after step three, chill injection) 66.8 6.48 58.7 81.2 min (at the end of step three) 65.9 6.47 61.2 As shown in Table 1, during the isothermal cooking stage in step one, the homogeneous temperature of the system was maintained at approximately 85℃, and the pH value was maintained between 5.28 and 5.34. This pH range is close to the isoelectric point range of muscle fibrous proteins, which helps to reduce the tissue binding resistance when fat migrates outward from the intermuscular spaces. Simultaneously, the surface tension of the aqueous phase was maintained between 27.4 mN / m and 28.1 mN / m during this stage, indicating a certain degree of interfacial activity regulation in the system. This facilitates the dispersion of heated free fat in the aqueous phase as small droplets, thereby slowing down the rapid aggregation of the macroscopic oil film.

[0086] In step two, after the flotation trigger agent was injected, the pH value of the system increased from 5.31 to 6.45, indicating that sodium bicarbonate reacted with the organic acids in the system, causing a significant change in the system's acid-base state. During this stage, the surface tension of the aqueous phase remained at a low level, indicating that the system could maintain a certain weak emulsified dispersion state during the short-term gas release process, providing conditions for the contact between bubbles and fat droplets.

[0087] In step three, after the injection of the low-temperature quenching demulsifier, the homogeneous temperature of the system decreased from 85.1℃ to 66.8℃, indicating that direct contact heat exchange with the low-temperature aqueous solution can reduce the system temperature in a short time. Simultaneously, the surface tension of the aqueous phase increased from 29.2 mN / m to 58.7 mN / m, reaching 61.2 mN / m at the end of step three. This change indicates a significant decrease in the interfacial activity of the system. Combined with the results of subsequent tests showing increased oil droplet size, decreased waste phase turbidity, and reduced residual oil concentration, this supports the conclusion that calcium ions participate in weakening the weakly emulsified structure and promoting oil droplet aggregation. Therefore, the air flotation triggering and quenching demulsification stages in Example 1 are sequentially related, which is beneficial for the formation of the floating oil layer during the subsequent static separation process.

[0088] Test Example 2: This test case is used to evaluate the comprehensive performance of the finished meat matrix and waste brine obtained in Example 1 and Comparative Examples 1, 3, 4 and 5, and to examine the effects of different process conditions on the effective oil removal rate, retention of fat-soluble flavor substances, meat shear force and organic load of waste brine.

[0089] The specific testing method includes the following steps: (1) Sample collection and pretreatment: 200g of muscle tissue from the center of each of the finished meat products after the operation of Example 1, Comparative Example 1, Comparative Example 3, Comparative Example 4 and Comparative Example 5 were cut and homogenized using a tissue homogenizer. 500mL of waste brine was collected from the bottom of each group after the surface oil was skimmed off and placed in a sealed sampling bottle for later use.

[0090] (2) Determination of effective oil removal rate: The surface oil formed and skimmed off during the static separation stage of each group was collected and weighed after removing the water and solid residue. Based on the initial total fat mass of the same batch of unprocessed fresh pork belly, the effective oil removal rate that can be macroscopically separated and recovered for each group was calculated. At the same time, the crude fat content of the homogenized meat matrix was determined by Soxhlet extraction as an auxiliary evaluation index of the residual fat level of the meat matrix.

[0091] (3) Determination of the cutoff of target fat-soluble aroma molecules: 5.00 g of meat matrix homogenate sample was weighed and placed in a headspace vial. 2-Octanol was added as an internal standard. The contents of trans-anestin and eugenol in the sample were determined by solid-phase microextraction-gas chromatography-mass spectrometry. Gas chromatography used a non-polar capillary column, and mass spectrometry used an electron impact ion source. Qualitative analysis was performed by comparing the retention time with the standard. The mass concentration of the target flavor substances was calculated using the internal standard method, with the unit being mg / kg.

[0092] (4) Meat shear force test: Standardized meat pieces with a length of 30 mm, a width of 15 mm, and a thickness of 15 mm were cut from each component of the meat product. The peak shear force was measured using a texture analyzer equipped with a Warner-Bratzler shearing blade. The probe descent speed was set to 2 mm / s, and the maximum force value during the shearing process was recorded in N.

[0093] (5) Determination of chemical oxygen demand (COD) of waste brine: The waste brine collected above was filtered through a 0.45 μm filter membrane to remove large particulate solids, and the COD value of the water sample was determined by the dichromate method. Before the test, the water sample was diluted by a fixed factor according to the estimated concentration, and the final result was converted into the original concentration, in mg / L.

[0094] Based on the above testing procedure, comparative test data for Example 1 and each comparative example were obtained, and the results are shown in Table 2. The effective oil removal rate is the percentage of the surface oil mass that can be macroscopically separated and recovered relative to the initial total fat mass of the raw meat.

[0095] Table 2. Comparison of overall effects between Example 1 and various comparative examples: Example 1 46.12 29.35 14.28 24.3 8750 Comparative Example 1 41.85 8.42 4.15 48.7 14200 Comparative Example 3 24.36 27.81 13.92 26.1 11450 Comparative Example 4 44.52 11.23 5.37 30.2 9120 Comparative Example 5 17.84 28.56 14.05 25.8 38640 As shown in Table 2, the effective oil removal rate of Example 1 was 46.12%, which is similar to that of Comparative Example 1. Meanwhile, the retention rates of trans-anestin and eugenol in Example 1 were 29.35 mg / kg and 14.28 mg / kg, respectively, which were higher than those in Comparative Example 1 (8.42 mg / kg and 4.15 mg / kg). The peak shear force of Example 1 was 24.3 N, lower than that of Comparative Example 1 (48.7 N). These results indicate that under relatively low heat intensity conditions, Example 1 can maintain effective oil removal while reducing the loss of fat-soluble flavor compounds and improving the texture of the finished meat.

[0096] Compared to Comparative Example 3, the effective oil removal rate of Example 1 increased from 24.36% to 46.12%. Comparative Example 3 did not include a flotation trigger, and its fat droplets mainly relied on natural buoyancy for separation; in Example 1, the gas generated by the reaction of sodium bicarbonate with organic acids facilitated the buoyancy and aggregation of fat droplets. Therefore, this comparative result demonstrates that the in-situ flotation step has a positive effect on improving the oil separation effect in a short time.

[0097] Compared to Comparative Example 4, Example 1 showed a similar effective oil removal rate, but a significantly higher retention rate of target flavor molecules. Comparative Example 4 used room temperature water as the calcium chloride carrier and lacked a low-temperature quenching process; its trans-anetinoside and eugenol retention rates were 11.23 mg / kg and 5.37 mg / kg, respectively. This result indicates that the low-temperature quenching demulsifier not only participates in the subsequent demulsification and separation process but also helps reduce the extent to which fat-soluble flavor substances continue to migrate into the aqueous phase after the high-temperature stage.

[0098] Comparative Example 5, without the addition of calcium chloride, showed an effective oil removal rate of 17.84%, but the COD value of the waste brine increased to 38640 mg / L. This result indicates that in the absence of calcium ions participating in demulsification, some fat may remain suspended in the waste brine as fine oil droplets, making it difficult to form a macroscopically skimmable oil layer, thus leading to a decrease in the effective oil removal rate and an increase in the organic load of the waste brine. Example 1, by introducing a low-temperature chilling demulsifier containing calcium chloride in the later stage, helps to improve the oil-water separation effect and reduce the organic load in the waste brine.

[0099] Test Example 3: This test case is used to evaluate the moisture phase distribution and surface color changes of the finished pork belly obtained in Example 1, Comparative Example 1 and Comparative Example 6, in order to examine the effects of different heat treatment intensities and material addition sequences on the internal moisture retention and appearance color of the finished meat.

[0100] The specific testing method includes the following steps: (1) Sample preparation and pretreatment: After the completion of the operation of Example 1, Comparative Example 1 and Comparative Example 6, the finished pork belly was cut into strips of the core part with a size of 10mm×10mm×20mm along the direction of the muscle fibers under constant temperature of 20℃. After gently absorbing the free water and oil on the sample surface with dust-free filter paper, it was immediately wrapped with a single layer of polytetrafluoroethylene film to reduce the evaporation of water during the test.

[0101] (2) Low-field NMR test: The wrapped meat strip sample was placed at the center of the radio frequency coil of the low-field NMR analyzer, and the ambient and sample temperature was controlled at 32℃. The instrument resonance frequency was set to 21MHz, and the spin-spin transverse relaxation time T2 of the sample was determined using CPMG pulse sequence. The test parameters were set as follows: 2000 sampling points, 0.2ms echo time interval, 2000ms isothermal waiting time, and 8 scan stacks.

[0102] (3) Spectral Inversion and Data Extraction: After acquiring the original exponentially decaying signal, the SIRT algorithm was used for multi-exponential inversion fitting to obtain the continuous distribution inversion spectrum of the transverse relaxation time T2. Based on the peak time range of the inversion spectrum, the peak areas corresponding to bound water T21, immobile water T22, and free water T23 were extracted by integration. Among them, the relaxation time range of T21 is 0.1ms to 10ms, the relaxation time range of T22 is 10ms to 100ms, and the relaxation time range of T23 is 100ms to 1000ms. Based on the proportion of each peak area to the total peak area, the relative proportion of different water phases was calculated.

[0103] (4) Surface color measurement: Cut relatively flat parts from the remaining meat pieces in each group above, and use a portable spectrophotometer to measure the surface color of the sample under D65 light source and 10° standard observer conditions, and record the brightness value L and redness value a. Each sample was randomly measured 5 times at different parts, and the arithmetic mean was taken as the final test result.

[0104] Based on the above testing procedure, the moisture phase distribution and surface color data of each group of samples were obtained, and the results are shown in Table 3.

[0105] Table 3. Results of moisture phase distribution and surface color testing of finished meat products from Example 1 and a specific comparative example: Example 1 4.31 86.54 9.15 45.26 12.38 Comparative Example 1 3.82 68.17 28.01 33.15 6.42 Comparative Example 6 4.15 74.39 21.46 38.64 8.71 As shown in Table 3, the area ratio of peak T22 in Example 1 was 86.54%, and the area ratio of peak T23 was 9.15%. Typically, peak T22 corresponds to relatively immobile water in the myofibrillar protein network; a higher proportion indicates that the water in the sample exists primarily in a relatively stable state. This result demonstrates that the relatively mild cooking conditions and subsequent low-temperature quenching treatment used in Example 1 helped maintain the proportion of immobile water in the finished meat and reduced the proportion of free water.

[0106] The area ratio of peak T22 in Comparative Example 1 was 68.17%, lower than that in Example 1; the area ratio of peak T23 was 28.01%, higher than that in Example 1. Meanwhile, the surface brightness value L and redness value a of Comparative Example 1 were 33.15 and 6.42, respectively, both lower than those of Example 1. These results indicate that under the high-temperature long-term treatment conditions of 95℃ for 120 min, the internal moisture state of the finished meat underwent significant changes, with an increase in the proportion of free water and a certain degree of decrease in surface color.

[0107] Comparative Example 6 added the flotation trigger and demulsifier all at once during the initial cooking stage. Its T22 peak area ratio was 74.39%, and its T23 peak area ratio was 21.46%, falling between that of Example 1 and Comparative Example 1. Its surface brightness value L and redness value a were also lower than those of Example 1. These results suggest that the order of material addition and the timing of its action have a certain impact on the moisture retention and surface color of the finished meat. Compared to Comparative Example 6, Example 1 implemented the weak emulsification, in-situ flotation, and rapid cooling demulsification steps in stages, which helps to reduce adverse changes in moisture state and surface color during processing.

[0108] Test Example 4: This test case is used to evaluate the changes in oil droplet size, waste water turbidity, and residual oil concentration in the liquid phase dispersion system of Examples 1, 2, and 5 during process operation, in order to examine the effects of extract addition and calcium salt demulsification steps on the liquid phase oil dispersion state and subsequent oil-water separation effect.

[0109] The specific testing method includes the following steps: (1) Sample collection: When the process of Example 1, Comparative Example 2 and Comparative Example 5 reached the end of step one, i.e., 75 min, 50 mL of liquid phase sample was extracted from the fluid area in the middle of the reactor using the sampling valve. After all processes were completed, the samples were allowed to stand and the upper floating oil was drained, and then 50 mL of aqueous phase sample was extracted from the bottom waste brine.

[0110] (2) Liquid phase oil droplet size determination: Liquid phase samples collected at different stages were transferred into the liquid sampler of the laser particle size analyzer, using pure water as the dispersion medium. The particle refractive index was set to 1.46, the dispersion medium refractive index to 1.33, and the light-blocking degree was controlled between 5% and 10%. The volume-weighted average particle size D4,3 of the dispersed oil droplets in the liquid phase was determined. Each sample was measured in triplicate, and the arithmetic mean was taken.

[0111] (3) Turbidity determination of waste water phase: Take the bottom waste brine sample that is finally discharged, and measure the turbidity of the water sample using a portable scattering light turbidimeter under constant temperature of 20℃. Before the measurement, the instrument is calibrated at multiple points using formalin standard solution, and the results are read and recorded. The unit is NTU.

[0112] (4) Determination of residual oil concentration in waste aqueous phase: Measure 25 mL of waste brine from the bottom and transfer it to a separatory funnel. Add petroleum ether and perform three extractions. Combine the extracts and dehydrate them with anhydrous sodium sulfate. Place them in a water bath to evaporate the solvent, and then dry them in a constant temperature drying oven until constant weight. Calculate the residual oil concentration in the waste aqueous phase by weighing the residue. The unit is mg / L.

[0113] Based on the above measurement procedure, the characteristics of each group of liquid phase dispersion systems and the final waste water phase index were obtained, and the results are shown in Table 4.

[0114] Table 4. Test data on the characteristics of the liquid-phase dispersion systems in Example 1 and specific comparative examples: Example 1 12.45 86.32 148.6 412.5 Comparative Example 2 58.74 62.18 415.3 1856.2 Comparative Example 5 11.82 13.65 4265.8 12480.4 As shown in Table 4, the oil droplet size D4,3 at the end of step one in Example 1 was 12.45 μm, indicating that the oil droplets in the liquid phase were in a small-sized dispersed state at this stage. After subsequent low-temperature quenching demulsifier treatment with calcium chloride and static separation, the residual oil droplet size D4,3 in the bottom aqueous phase increased to 86.32 μm, the turbidity of the waste aqueous phase was 148.6 NTU, and the residual oil concentration was 412.5 mg / L. The above results indicate that the calcium salt demulsification treatment in the later stage of Example 1 helps to promote the aggregation of dispersed oil droplets and reduce the content of suspended oil droplets in the final waste aqueous phase.

[0115] Comparative Example 2, without the addition of licorice extract powder and hawthorn extract powder, had an oil droplet size (D4,3) of 58.74 μm at the end of step one, higher than that of Example 1. This result indicates that the oil droplet dispersion state in the system differs from that of Example 1 in the absence of glycyrrhizic acid's surface activity regulation and hawthorn organic acid as a gas release substrate. After static separation, the oil droplet size (D4,3) in the aqueous phase of Comparative Example 2 was 62.18 μm, the turbidity of the waste aqueous phase was 415.3 NTU, and the residual oil concentration was 1856.2 mg / L, all higher than that of Example 1, indicating that under conventional dispersion and separation conditions, a significant amount of oil components were still retained in the final waste aqueous phase.

[0116] Comparative Example 5, without the addition of anhydrous calcium chloride, had an oil droplet size D4,3 of 11.82 μm at the end of Step 1, similar to Example 1. However, after settling and separation, the oil droplet size D4,3 in the aqueous phase was only 13.65 μm, the turbidity of the waste aqueous phase increased to 4265.8 NTU, and the residual oil concentration increased to 12480.4 mg / L. These results indicate that, in the absence of a calcium salt demulsification step, small-diameter oil droplets are less likely to form large aggregates during settling, and a significant amount of oil remains dispersed in the waste aqueous phase. Therefore, the weak emulsification dispersion step and the subsequent calcium salt demulsification step have a synergistic effect in improving oil-water separation.

[0117] Test Example 5: This test case is used to evaluate the formation of the floating oil layer and the lipid oxidation level of the finished meat during the static separation stage of Example 1, Comparative Example 1 and Comparative Example 3, in order to examine the influence of the in-situ air flotation step and heat treatment conditions on the oil phase separation process and the oxidation index of the finished product.

[0118] The specific testing method includes the following steps: (1) Dynamic separation thickness monitoring: During the final settling separation stage of the process, observations were made on the corresponding steps four of Example 1 and Comparative Example 3, and the corresponding shutdown settling stage of Comparative Example 1. Using a graduated transparent liquid level sight glass on the side wall of the reactor, the cumulative thickness of the floating oil layer on the liquid surface was recorded at different time points after the agitator had completely stopped running. The recording time points were 0.5 min, 1.0 min, 2.0 min, 3.0 min, and 4.0 min. The readings were taken as the vertical distance from the gas-liquid interface to the oil-water interface, in mm.

[0119] (2) Preparation of meat extract: 20g of meat with some subcutaneous fat was cut from the finished product after the process of each group was completed and crushed using a tissue homogenizer. 5.00g of meat paste was weighed and placed in a centrifuge tube, and 25mL of trichloroacetic acid mixed extraction solution containing 0.1% dibutylhydroxytoluene was added. After homogenization, the mixture was centrifuged at 4000r / min for 15min at 4℃, and the supernatant was collected for later use.

[0120] (3) Determination of lipid oxidation degree: Take 5 mL of the above supernatant and transfer it into a stoppered colorimetric tube. Add 5 mL of 0.02 mol / L thiobarbituric acid solution and mix well. Place the colorimetric tube in a 90℃ water bath for 40 min, and then remove it and cool it rapidly to room temperature. Measure the absorbance of the solution at 532 nm using a UV-Vis spectrophotometer and subtract the reagent blank. Calculate the malondialdehyde content in the sample based on the pre-plotted 1,1,3,3-tetraethoxypropane standard curve, and express the thiobarbituric acid reactant value as the mass of malondialdehyde per kilogram of meat sample, in mg / kg.

[0121] Based on the above measurement procedure, the changes in the thickness of the floating oil layer and the TBARS value of the finished meat during the static separation stage were obtained. The results are shown in Table 5.

[0122] Table 5. Evolution of oil layer thickness and meat quality TBARS test data after static separation in Example 1 and specific comparative examples: Example 1 4.8 18.2 34.6 41.5 43.1 0.31 Comparative Example 1 2.5 6.7 15.2 26.8 35.4 0.94 Comparative Example 3 1.2 3.5 8.1 14.6 19.3 0.36 As shown in Table 5, during the static separation stage, the thickness of the floating oil layer in Example 1 increased rapidly with time, reaching 34.6 mm at 2.0 min and 43.1 mm at 4.0 min. In Comparative Example 3, the thicknesses of the floating oil layer at the same time points were 8.1 mm and 19.3 mm, respectively, which were lower than those in Example 1. These results indicate that in Example 1, the in-situ air flotation step may help accelerate the migration and aggregation of dispersed oil droplets to the liquid surface, thereby increasing the formation rate of the floating oil layer in a short time.

[0123] Compared to Comparative Example 3, Example 1 added a flotation triggering agent in step two, where sodium bicarbonate reacted with organic acids in the system to generate gas. This process may promote contact between bubbles and oil droplets, giving some oil droplets additional upward buoyancy. Comparative Example 3 did not include a flotation triggering step; the oil droplets mainly floated due to the density difference between themselves and the continuous aqueous phase, resulting in a relatively low rate of oil layer formation within the test time range.

[0124] Comparative Example 1 employed a high-temperature, long-time cooking process at 95°C for 120 minutes, resulting in an oil layer thickness of 35.4 mm after 4.0 minutes, which was lower than that of Example 1 but higher than that of Comparative Example 3. This result indicates that high-temperature, long-time treatment can promote the precipitation of some oils, but the formation rate of the oil layer in the initial stage of static separation is still lower than that of Example 1.

[0125] Regarding lipid oxidation indicators, the TBARS value of Comparative Example 1 was 0.94 mg / kg, higher than that of Example 1 (0.31 mg / kg) and Comparative Example 3 (0.36 mg / kg). This result indicates that the lipid oxidation level of the finished meat is relatively high under high-temperature, long-term treatment conditions. The TBARS values ​​of Example 1 and Comparative Example 3 are similar, suggesting that the degree of lipid oxidation in the finished meat is low under relatively mild cooking conditions of 85°C for 75 min. Example 1, in particular, further incorporated a subsequent low-temperature quenching operation, which helped reduce the adverse effects of the subsequent high-temperature residence time on lipid oxidation indicators.

[0126] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A process for enhancing the quality and aroma of braised meat through synergistic degreasing with compound spices, comprising the following steps: S1. Preparation of materials: Based on 100 parts by weight of total water, prepare pre-treated meat chunks, seasonings, 0.5-1.0 parts of spice powder, 0.1-0.2 parts of licorice extract, and 0.3-0.5 parts of hawthorn extract containing 20%-30% total organic acids; prepare an aqueous solution of chilling agent containing 0.05-0.08 parts of anhydrous calcium chloride at a temperature of 0-4°C; prepare an aqueous solution of flotation agent according to the citric acid equivalent molar ratio of sodium bicarbonate to the total organic acids being 0.75:1-0.85:

1. S2. Cooking: Add the remaining water (excluding the water used for preparation) and the above dry materials to the reaction vessel, and add the meat chunks at 82-85℃ and a stirring speed of 30-50 r / min and cook for 60-90 min. S3, Air flotation: Maintain the temperature and rotation speed, inject the air flotation agent aqueous solution into the reactor, and react for 1.0 to 1.5 minutes; S4. Demulsification: Stop heating and turn on cooling. Inject the quenching agent aqueous solution into the reactor. Reduce the stirring speed to 10-15 r / min and maintain it for 4-6 min until the system temperature drops to 65-68℃. S5. Separation: Stop stirring, let stand for 3-5 minutes to form an oil layer, separate the oil layer and discharge the material.

2. The process for enhancing the quality and aroma of braised meat through synergistic degreasing of compound spices according to claim 1, characterized in that, In S1, the spice powder containing fat-soluble aroma components is composed of star anise powder, clove powder and cinnamon powder, and the mass ratio of star anise powder, clove powder and cinnamon powder is 2:1:

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3. The process for enhancing the quality and aroma of braised meat through synergistic degreasing of compound spices according to claim 1, characterized in that, The licorice extract powder described in S1 is prepared by the following steps: After pulverizing the rhizome of Glycyrrhiza glabra, add 6 to 10 times its weight of an ammonia solution with a mass fraction of 0.3 to 0.8%, and extract countercurrently at 75 to 85°C for 1.5 to 2.5 hours to obtain an extract. After centrifugation, take the supernatant and pass it through an ultrafiltration membrane with a molecular weight cutoff of 3000 Da to remove macromolecular impurities. Collect the filtrate and concentrate it under reduced pressure to a relative density of 1.15 to 1.25, and then spray dry to obtain the licorice extract powder.

4. The process for enhancing the quality and aroma of braised meat through synergistic degreasing of compound spices according to claim 3, characterized in that, The mass fraction of glycyrrhizic acid in the licorice extract powder is 60-70%. In the preparation steps, the centrifugation speed is 4000 r / min and the time is 15 min; the inlet air temperature of the spray drying is 150-170℃ and the outlet air temperature is 75-85℃.

5. The process for enhancing the quality and aroma of braised meat through synergistic degreasing of compound spices according to claim 1, characterized in that, The hawthorn extract powder described in S1 is prepared by the following steps: After pulverizing dried hawthorn fruit, add 8-12 times its weight of a 50-70% ethanol aqueous solution and perform ultrasonic-assisted reflux extraction at 50-70℃ for 1.0-2.0 h. After filtration, the extract is subjected to vacuum distillation to recover the ethanol, yielding an aqueous extract. The aqueous extract is then passed through a chromatography column packed with a hydrogen-type D001 macroporous strong acid styrene-based cation exchange resin for desalting and release. The unadsorbed eluent and the pure water eluent are collected, combined, and concentrated under reduced pressure. Subsequently, the mixture is freeze-dried at ~40℃ to obtain the hawthorn extract powder.

6. The process for enhancing the quality and aroma of braised meat through synergistic degreasing of compound spices according to claim 5, characterized in that, In the preparation step, the flow rate of the aqueous extract through the chromatography column is 2 BV / h, and the volume of the collected pure water eluent is 2 BV.

7. The process for enhancing the quality and aroma of braised meat through synergistic degreasing of compound spices according to claim 1, characterized in that, In S1, the amount of water used to prepare the chilling demulsifier is 15.0 to 20.0 parts.

8. The process for enhancing the quality and aroma of braised meat through synergistic degreasing of compound spices according to claim 1, characterized in that, In step S3, the air flotation trigger agent is injected into the reactor within 15-20 seconds using a feeding pump; in step S4, the chilling demulsifier is injected into the reactor within 20-30 seconds using a delivery pump.

9. The process for enhancing the quality and aroma of braised meat through synergistic degreasing of compound spices according to claim 1, characterized in that, The specific implementation method of S5 is as follows: open the overflow weir at the top of the reactor to discharge the surface oil and solid residues carried by the liquid to the waste oil system; open the bottom valve of the reactor to discharge the liquid and meat chunks.

10. The process for enhancing the quality and aroma of braised meat through synergistic degreasing of compound spices according to claim 1, characterized in that, In S1, the meat chunks are pork belly chunks or chicken leg chunks with skin.