Multidimensional regulation method of meat product quality based on lycopene complex emulsion

Abstract

The application discloses a kind of based on lycopene composite emulsion meat product quality multidimensional regulation method, belong to meat preparation technical field.The method aims at solving the uneven dispersion of lycopene in meat paste, poor stability and the problem of unable to actively regulate protein conformation to improve product quality in prior art.The technical scheme points include: first, meat paste containing salt, sodium tripolyphosphate and ice water is prepared to form salt-soluble protein extraction system;Subsequently, heat-induced protein-polysaccharide complex emulsification system is constructed, soybean protein isolate solution is heated, mixed with lycopene, melted lard and inulin, and then lycopene-loaded emulsion is prepared by multi-stage high-pressure homogenization;The emulsion is mixed with meat paste by low-frequency chopping and high-frequency chopping process;Finally, the chopped meat paste is cooked, shaped, cooled and frozen.This method is mainly used for producing meat products with high oxidative stability and excellent texture.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of meat preparation. More particularly, the present application relates to a method for multi-dimensional regulation of meat product quality based on lycopene complex emulsion. BACKGROUND

[0002] Emulsified meat products are favored by consumers due to their good juiciness and elasticity, but their quality is prone to deterioration due to lipid and protein oxidation during processing and storage. Adding natural antioxidants such as lycopene is an effective strategy to improve this problem. However, there are obvious limitations in traditional addition methods: when added in the form of tomato paste, tomato powder, etc., the complex components (sugar, acid, organic acid, fiber) will uncontrollably affect the microenvironment of the protein gel network formation of the meat paste, resulting in large fluctuations in product quality; and when using purified lycopene extract, its strong hydrophobicity leads to its difficulty in dispersing in the meat paste, easy aggregation, and inability to effectively contact the oxidation sites (lipid droplet interface, protein hydrophobic region), limiting the antioxidant potential.

[0003] Existing improvement methods mostly focus on dissolving lycopene in the oil phase and then emulsifying and dispersing it, but the conventional emulsion formed has a simple interface and insufficient stability, and the oil droplets are prone to aggregation and rupture during subsequent meat paste chopping, heating and gelation, resulting in uneven distribution of lycopene and decreased antioxidant efficiency. More importantly, existing technologies only stop at adding what and its impact on the final quality, which is a black box operation, and lack of knowledge and control means on how to add and how the functional factors actively affect the conformational changes, aggregation path and final network structure of proteins. The influence mechanism of functional factors on the digestion behavior and nutrient release pattern in the gastrointestinal tract is even less known.

[0004] Therefore, it has become an urgent technical need in the field to develop an innovative method that can stabilize lycopene function and actively intervene in the protein assembly process, achieving editable regulation of the oxidative stability, texture characteristics and nutrient release pattern of meat products. This requires not only to build a stable lycopene delivery system, but also to reveal and utilize the molecular mechanism of its interaction with muscle proteins, achieving a paradigm shift from "passive addition" to "active conformational regulation". SUMMARY

[0005] It is an object of the present application to solve at least the above problems and to provide at least the advantages stated hereinafter.

[0006] In order to achieve these objects and other advantages in accordance with the present application, a method for multi-dimensional regulation of meat product quality based on lycopene complex emulsion is provided, comprising the following steps:

[0007] S1, preparing a basic meat paste: grinding fresh meat, adding 2.0% of salt, 0.2%-0.3% of sodium tripolyphosphate and 20% of ice water by weight of the meat, and chopping and mixing at 4-8℃ to form a basic meat paste;

[0008] S2, constructing a heat-induced protein-polysaccharide complex emulsification system, specifically including the following steps:

[0009] S2.1, taking a 4%-8% soybean protein isolate aqueous solution, heating in a water bath at 85-95℃ for 20-40 minutes, and then cooling to 40-60℃ to obtain a protein solution;

[0010] S2.2, adding molten lycopene-pig fat and food-grade inulin to the protein solution, mixing to obtain a pretreatment liquid; wherein the mass ratio of the molten lycopene-pig fat to the protein solution is 1:1-3, the addition amount of the molten lycopene-pig fat is 5%-10% of the total mass of the basic meat paste, the addition amount of the lycopene is 0.002%-0.015% of the total mass of the basic meat paste, and the addition amount of the inulin is 2%-5% of the mass of the molten lycopene-pig fat;

[0011] S2.3, homogenizing the pretreatment liquid at 50-80MPa for 2-4 times, and then homogenizing at 100-150MPa for 1-3 times to obtain a lycopene-loaded emulsion;

[0012] S2.4, adding the lycopene-loaded emulsion to the basic meat paste of S1, chopping and mixing at a low frequency of 1500-2500rpm for 2-4 minutes, and then chopping and mixing at a high frequency of 3500-4500rpm for 3-6 minutes to obtain a chopped meat paste;

[0013] S3, molding and post-processing: cooking the chopped meat paste in hot water at 80-85℃ to form a meat product, and then cooling, packaging and freezing at-18℃ or below.

[0014] Preferably, in the step S2.3, after homogenizing at 100-150MPa for 1-3 times, a homogenate is obtained, and the homogenate is subjected to the following operations to obtain the lycopene-loaded emulsion: adding 0.05%-0.2% of rosemary extract and 0.1%-0.3% of β-sitosterol to the homogenate by weight of the total mass of the homogenate, stirring at 40-50℃ and 3000-5000rpm for 15-30 minutes, and then cooling to 4℃ within 5 minutes and standing for 12-24 hours to obtain the lycopene-loaded emulsion.

[0015] Preferably, after the cooking setting of S3 step, a quality maintenance agent soaking step S3.1 is further included, which is specifically as follows: after the meat product after cooking setting is immersed in a quality maintenance agent solution, it is taken out after being soaked at 4-8℃ for 30-60 minutes, then drained, and then packaged and frozen; the quality maintenance agent solution is an aqueous solution containing 1%-3% trehalose and 0.5%-1.5% konjac glucomannan.

[0016] Preferably, after the standing ripening of S2.3 step for 12-24 hours, a standing liquid is obtained, and the standing liquid is subjected to the following operation to obtain a lycopene-loaded emulsion: the standing liquid is incubated with an equal volume of papain solution at 37℃ and pH 7.0, oscillated at 100-150 rpm for 20-40 minutes, then heated at 85℃ for 5 minutes to inactivate the enzyme, and cooled to below 4℃ within 5 minutes to obtain the lycopene-loaded emulsion; wherein the enzyme activity of the papain solution is 500-2000 U / mL.

[0017] Preferably, the S1 step specifically includes:

[0018] S1.1, pre-hydration: mixing a portion of ice water accounting for 20%-40% of the total amount of ice water with the composite flavor carrier to form a flavor carrier solution by stirring until completely dissolved and dispersed; the composite flavor carrier contains 0.5%-1% yeast extract, 0.2%-0.5% mushroom powder, and 0.5%-1% modified citrus fiber, and the balance is a food-grade carrier;

[0019] S1.2, chopping and extracting: chopping fresh meat, and chopping and extracting the fresh meat with 2.0% of salt accounting for the mass of the meat, 0.2%-0.3% of sodium tripolyphosphate accounting for the mass of the meat, the flavor carrier solution, and the remaining ice water at 4-8℃ to form the basic meat paste;

[0020] wherein the total amount of the composite flavor carrier accounts for 3%-6% of the total mass of the basic meat paste; and the modified citrus fiber is prepared by high-pressure homogenization treatment of citrus fiber to dissociate the fiber bundles.

[0021] Preferably, the chopping in the S2.4 step is carried out in a chopping system with online viscosity feedback control, and the chopping process specifically includes:

[0022] S6.1, monitoring the apparent viscosity of the meat paste in real time during the low-frequency chopping stage;

[0023] S6.2, when the apparent viscosity reaches a first preset threshold η1, the system automatically switches to the high-frequency chopping stage;

[0024] S6.3, during the high-frequency chopping stage, the apparent viscosity of the meat batter is continuously monitored, and when the rate of increase of the apparent viscosity is lower than a second preset threshold Δη / Δt, the system determines that the conformation editing is completed, and automatically stops the chopping.

[0025] Preferably, after the cooling in step S3, a step of coating the Maillard reaction substrate with a heat-induced gel is further included, which is specifically as follows:

[0026] S7.1, preparing a coating solution: the coating solution includes 3%-6% pea protein hydrolysate, 1%-2% D-ribose, 0.5%-1.5% sodium alginate, and 1%-3% potato starch, and the rest is water;

[0027] S7.2, immersing the meat batter after cooking, setting and cooling in the coating solution, and taking it out after 5-15 seconds to form a uniform thin layer;

[0028] S7.3, placing the coated meat batter in an environment with a temperature of 85-95°C and a humidity of 70%-80%, and performing hot air treatment for 8-15 minutes to make the coating pre-gelatinize and mature, and then performing frozen storage.

[0029] Preferably, the cooking process in step S3 adopts a programmed temperature rising mode, which specifically includes:

[0030] S8.1, placing the chopped meat batter in a water bath with an initial temperature of 50°C and keeping it for 10-15 minutes;

[0031] S8.2, increasing the water temperature from 50°C to 72°C at a temperature rising rate of 0.8-1.2°C per minute;

[0032] S8.3, keeping the temperature at 72°C for 5-10 minutes;

[0033] S8.4, transferring the product to hot water with a temperature of 85°C, and cooking for 5 minutes to complete the final setting.

[0034] The present application at least includes the following beneficial effects:

[0035] First, by creating a heat-induced protein-polysaccharide complex emulsification system, the key qualities of meat products can be improved, which are specifically as follows: 1) nanocapsulation and complex interface layer work together to greatly improve the thermal stability and storage stability of lycopene, thereby more effectively inhibiting lipid and protein oxidation (the lowest TBARS value and carbonyl value); 2) by locking the protein in a partially denatured state, a weak gel network of energy dissipation type is induced, which gives the product better juiciness and elasticity; 3) the edited protein conformation lays a foundation for subsequent implementation of stage-specific digestion behavior.

[0036] Second, by introducing rosemary extract and β-sitosterol for interfacial synergistic stabilization, the complex interface layer can effectively resist the physical and oxidative stress caused by subsequent severe chopping, cooking and frozen storage, ensuring that the lycopene-loaded complex emulsion system remains structurally intact and functionally active when it reaches the final product, thereby stabilizing and reproducing the oxidative stability and conformational editing effect in the harsh processing chain.

[0037] Third, through the synergistic effect of trehalose and konjac glucomannan, the destruction of the gel network by ice crystal growth during frozen storage can be effectively inhibited, thereby reducing the juice loss rate of the product during thawing and reheating, and maintaining the tender and juicy texture of the product for a long time, solving the industry pain point of dry and hard taste of frozen meat products.

[0038] Fourth, by introducing a complex flavor carrier composed of yeast extract, mushroom powder and modified citrus fiber, the problems of insufficient flavor and texture deterioration of meat products are improved. Yeast extract and mushroom powder build a rich and natural meaty bottom note through umami synergistic effect, effectively masking the unpleasant flavors that functional components may bring. Modified citrus fiber acts as a physical barrier to achieve slow release of flavor and long-term retention of juice. Finally, in the trend of salt and fat reduction, a satisfying sensory experience is still provided.

[0039] Fifth, by converting the abstract "protein conformational editing" state into an engineering parameter (viscosity and its rate of change) that can be monitored and controlled online, the intelligent feedback control system can automatically compensate for raw material fluctuations and environmental disturbances, ensuring that each batch of product can accurately reproduce the optimal "conformational editing" state, thereby reducing the batch-to-batch variability of key product qualities (such as texture and water holding capacity) to a very low level, greatly improving production efficiency and product consistency.

[0040] Sixth, by constructing a Maillard reaction substrate and a heat-induced gel coating system on the surface of the product, the coating can quickly produce rich and attractive Maillard flavor and uniform brown color during terminal cooking, while its gel network acts as an intelligent barrier layer to effectively prevent the evaporation and loss of internal juice, ultimately improving the sensory quality of the product and greatly enhancing the market appeal of the product.

[0041] Seventh, through programmed temperature rising cooking process, the edited protein molecules can be denatured and cross-linked in sequence and gently. This precise control of the timing of heat input avoids the instantaneous disordered aggregation of proteins, guiding the formation of a more fine, uniform and dense three-dimensional gel network structure. This not only balances the product texture (elasticity and tenderness), but also further optimizes the overall water holding capacity and distribution stability of functional factors of the product.

[0042] Additional advantages, objects, and features of the application will be apparent from the following description, taken in conjunction with the accompanying drawings. DETAILED DESCRIPTION

[0043] The application will be further described in conjunction with the following examples, which enable a person skilled in the art to implement the application according to the description.

[0044] The application discloses a method for multi-dimensional quality regulation of meat products based on lycopene composite emulsion, comprising the following steps:

[0045] S1, preparing a basic meat paste: grinding fresh meat, adding 2.0% of salt, 0.2%-0.3% of sodium tripolyphosphate and 20% of ice water in the mass of fresh meat, and chopping and stirring at 4-8 DEG C to form a salt-soluble protein extraction system, i.e. the basic meat paste;

[0046] S2, constructing a heat-induced protein-polysaccharide composite emulsification system, specifically comprising the following steps:

[0047] S2.1, dispersing food-grade soybean protein isolate in water to prepare a soybean protein isolate aqueous solution with a mass concentration of 4%-8%, heating in a water bath at 85-95 DEG C for 20-40 minutes, and then cooling to 40-60 DEG C to obtain a protein solution;

[0048] S2.2, adding melted lard with lycopene and food-grade inulin into the protein solution, and mixing to obtain a pretreatment liquid; wherein the mass ratio of the melted lard to the protein solution is 1:1-3, the addition amount of the melted lard accounts for 5%-10% of the total mass of the basic meat paste, the addition amount of the lycopene accounts for 0.002%-0.015% of the total mass of the basic meat paste, and the addition amount of the inulin accounts for 2%-5% of the mass of the melted lard;

[0049] S2.3, homogenizing the pretreatment liquid at 50-80 MPa for 2-4 times, and then homogenizing at 100-150 MPa for 1-3 times to obtain a lycopene-loaded emulsion;

[0050] S2.4, adding the lycopene-loaded emulsion into the meat paste of S1, chopping and stirring at a low frequency of 1500-2500 rpm for 2-4 minutes, and then chopping and stirring at a high frequency of 3500-4500 rpm for 3-6 minutes to obtain chopped meat paste;

[0051] S3, molding and post-processing: cooking and molding the chopped meat paste in hot water at 80-85 DEG C to obtain meat products, and then cooling, packaging and freezing at-18 DEG C or below.

[0052] In the above technical solution, when the meat product is processed, the basic meat paste preparation step is first carried out. Fresh pork, beef or chicken can be selected as raw meat, which is ground by a meat grinder. The meat grinder can be an electric meat grinder commonly used on the market. Then prepare the materials needed for the salt-soluble protein extraction system. The amount of salt added is accurately weighed according to 2.0% of the mass of the meat. Sodium tripolyphosphate can be selected as a food-grade powdered product, and the amount is weighed according to 0.2%, 0.25% or 0.3% of the mass of the meat. Ice water is prepared according to 20% of the mass of the meat, and the temperature is controlled at 4°C, 6°C or 8°C. The ground meat, the weighed salt, the sodium tripolyphosphate and the ice water are added to a chopper together. The chopper can be a planetary chopper. Chopping is carried out at an ambient temperature of 4-8°C. The speed and time are controlled during the chopping process to ensure that the materials are fully mixed to form a uniform salt-soluble protein extraction system, which is the basic meat paste. The temperature of the material can be monitored by a temperature sensor during the process to ensure that the temperature is within the set range.

[0053] Then the heat-induced protein-polysaccharide complex emulsion system is constructed. First, prepare the protein solution. Food-grade soybean protein isolate can be selected as a high-purity powder product available on the market. It is dispersed in pure water to prepare a protein solution with a mass concentration of 4%, 6% or 8%. Then the protein solution is placed in a water bath. The water bath can be a digital constant-temperature water bath. The water temperature is set to 85°C, 90°C or 95°C. The protein solution is heated for 20 minutes, 30 minutes or 40 minutes. After the heating of the protein solution is completed, it is naturally cooled to 40°C, 50°C or 60°C. In the second step, a pretreatment solution is prepared. The protein solution is added with melted lard containing lycopene and food-grade inulin. Lycopene can be selected as an oil-soluble food-grade product. The melted lard is obtained by heating and melting edible lard (lycopene is pre-melted into the melted lard: heat the lard to complete melting, maintain at 50°C, add food-grade lycopene, and magnetically stir until completely dissolved to obtain a uniform solution, which is the melted lard containing lycopene). The mass ratio of the melted lard (without lycopene) to the protein solution can be 1:1, 1:2 or 1:3, and the amount of the melted lard added is 5%, 8% or 10% of the total mass of the basic meat paste. The amount of lycopene added is 0.002%, 0.008% or 0.015% of the total mass of the basic meat paste. Inulin can be selected as a commercially available food-grade powder, and the amount added is 2%, 3.5% or 5% of the mass of the melted lard (without lycopene). These materials are mixed uniformly to obtain the pretreatment solution.

[0054] The third step is to prepare the lycopene-loaded emulsion. The pretreated solution is fed into a high-pressure homogenizer, which can be a laboratory or industrial high-pressure homogenizing device. First, the pressure is adjusted to 50 MPa, 65 MPa, or 80 MPa, and the solution is homogenized for 2 times, 3 times, or 4 times. Then, the pressure is adjusted to 100 MPa, 125 MPa, or 150 MPa, and the solution is homogenized for 1 time, 2 times, or 3 times. The fourth step is to mix the meat paste. The prepared lycopene-loaded emulsion is added to the previously prepared base meat paste. The chopper is used again. First, the low-frequency speed is adjusted to 1500 rpm, 2000 rpm, or 2500 rpm, and the chopper is operated for 2 minutes, 3 minutes, or 4 minutes. Then, the high-frequency speed is adjusted to 3500 rpm, 4000 rpm, or 4500 rpm, and the chopper is operated for 3 minutes, 4.5 minutes, or 6 minutes. Finally, the chopped meat paste is obtained.

[0055] Finally, the shaping and post-processing are performed. The chopped meat paste is placed in a mold, which can be a stainless steel or food-grade plastic mold. The mold is shaped according to the desired shape and size of the meat product. After shaping, the meat product is cooked in hot water at 80°C, 82°C, or 85°C. The cooking process can be performed in a cooking pot, which can be a stainless steel pot with temperature control function. The cooking time is determined according to the size of the meat product. After shaping, the meat product is removed and naturally cooled to room temperature. The cooling process can be performed in a clean cooling room, which is kept ventilated and sanitary. The cooled meat product is packaged using food-grade packaging materials, such as plastic film or packaging bag with good barrier properties. After packaging, the meat product is placed in a freezing device, such as an industrial freezer or refrigerator, and stored at a temperature below -18°C. The temperature of the freezing device is monitored regularly during the freezing process to ensure stable temperature.

[0056] Through the above specific implementation, a meat product that meets the process requirements can be prepared. In the processing process, the parameter control and material selection of each step meet the food processing specifications. The equipment and materials used are conventional products available on the market, and the operation process is easy to control. This method can effectively realize the full preparation of meat paste, the stable construction of heat-induced protein-polysaccharide complex emulsion system, and the shaping and proper post-processing of meat products, which helps to improve the overall quality of meat products, ensures the stability of meat products during processing and storage, and meets the basic requirements and relevant standards of food processing.

[0057] The technical effects of the technical solution are illustrated by the following examples and comparative examples.

[0058] <Example 1>

[0059] The meat product is prepared as follows:

[0060] 1. S1 preparation of basic meat emulsion: select fresh pork, grind it with a meat grinder, add 2.0% of salt, 0.25% of sodium tripolyphosphate and 20% of ice water (temperature controlled at 6℃) by weight of the meat, put the above materials into a chopper, continuously chop for 8 minutes at 6℃, form a uniform salt-soluble protein extraction system, which is the basic meat emulsion.

[0061] 2. S2 construction of heat-induced protein-polysaccharide complex emulsifying system:

[0062] S2.1, weigh the food-grade soybean protein isolate, disperse it in pure water, stir until completely dissolved, prepare a protein solution with a mass concentration of 4%; put the protein solution into a constant temperature water bath, heat in water bath at 90℃ for 30 minutes, cool to 50℃, and obtain the protein solution;

[0063] S2.2, add the molten lycopene-pig oil (the addition amount of food-grade lycopene is 0.006% of the total mass of the basic meat emulsion), molten pig oil (the addition amount is 7.5% of the total mass of the basic meat emulsion, and the mass ratio of protein solution is 1:2) and food-grade inulin (the addition amount is 3% of the mass of molten pig oil) to the protein solution, mix with a stirrer for 10 minutes to obtain a pretreatment solution. The preparation of molten lycopene-pig oil is as follows: heat the pig oil to complete melting, maintain at 50℃, add food-grade lycopene, and magnetically stir until completely dissolved to obtain a uniform solution, which is the molten lycopene-pig oil.

[0064] S2.3, send the pretreatment solution into a high-pressure homogenizer, first homogenize 3 times at a pressure of 65MPa, stop for 2 minutes after each homogenization, then adjust the pressure to 125MPa, and homogenize 2 more times to obtain a lycopene-loaded emulsion.

[0065] S2.4, add the lycopene-loaded emulsion to the basic meat emulsion prepared in S1, first chop for 3 minutes at a low frequency of 2000rpm, then adjust to a high frequency of 4000rpm and chop for 4.5 minutes to obtain the chopped meat emulsion.

[0066] 3. S3 molding and post-processing: pour the chopped meat emulsion into a rectangular stainless steel mold (specification 10cm×5cm×3cm), gently compact and form; put the mold into a 82℃ hot water pot, cook for 25 minutes to complete the shaping, obtain the meat product; take out the meat product after shaping, naturally cool to room temperature, package with food-grade polyethylene film, and put into a-18℃ freezer for frozen storage.

[0067] <Example 2>

[0068] 1. S1 Preparation of basic meat emulsion: Fresh beef is selected, ground and added with 2.0% of salt, 0.2% of sodium tripolyphosphate and 20% of ice water (temperature 4℃) by weight of meat, chopped in a chopper for 7 minutes at 4℃ to form a salt-soluble protein extraction system, which is the basic meat emulsion.

[0069] 2. S2 Construction of heat-induced protein-polysaccharide composite emulsification system:

[0070] S2.1, same as example 1.

[0071] S2.2, same as example 1.

[0072] S2.3, the pretreatment solution is first homogenized 4 times at 50 MPa and then 3 times at 100 MPa to prepare a lycopene-loaded emulsion.

[0073] S2.4, after the lycopene-loaded emulsion is added to the basic meat emulsion, it is first chopped at a low frequency of 1500 rpm for 4 minutes and then chopped at a high frequency of 3500 rpm for 6 minutes to obtain chopped meat emulsion.

[0074] 3. S3 molding and post-processing: the chopped meat emulsion is poured into molds of the same size, cooked in 80℃ hot water for 30 minutes for setting, packaged after cooling and frozen at -18℃.

[0075] <Example 3>

[0076] 1. S1 Preparation of basic meat emulsion: Fresh chicken meat is selected, ground and added with 2.0% of salt, 0.3% of sodium tripolyphosphate and 20% of ice water (temperature 8℃) by weight of meat, chopped in a chopper for 9 minutes at 8℃ to form a salt-soluble protein extraction system, which is the basic meat emulsion.

[0077] 2. S2 Construction of heat-induced protein-polysaccharide composite emulsification system:

[0078] S2.1, same as example 1.

[0079] S2.2, same as example 1.

[0080] S2.3, the pretreatment solution is first homogenized 2 times at 80 MPa and then 1 time at 150 MPa to prepare a lycopene-loaded emulsion.

[0081] S2.4, after the lycopene-loaded emulsion is added to the basic meat emulsion, it is first chopped at a low frequency of 2500 rpm for 2 minutes and then chopped at a high frequency of 4500 rpm for 3 minutes to obtain chopped meat emulsion.

[0082] 3. S3 molding and post-processing: the chopped meat emulsion is poured into molds of the same size, cooked in 85℃ hot water for 20 minutes for setting, packaged after cooling and frozen at -18℃.

[0083] <Comparative Example 1>

[0084] Comparative Example 1 differs from Example 1 in that the conventional processing method of "heat- induced protein-polysaccharide complex emulsification system" is absent, and is as follows:

[0085] 1. Preparation of base meat batter: same as Example 1.

[0086] 2. Direct mixing and chopping: lycopene was weighed and directly mixed with melted pork oil, and then added to the above base meat batter, and first chopped at a low frequency of 2000 rpm for 3 minutes, and then chopped at a high frequency of 4000 rpm for 4.5 minutes. The amounts of the components were the same as in Example 1.

[0087] 3. Molding and post-processing: same as Example 1.

[0088] <Comparative Example 2>

[0089] Comparative Example 2 differs from Example 1 in that the homogenization process parameters are different, and are as follows:

[0090] 1. Preparation of base meat batter S1: same as Example 1.

[0091] 2. Construction of emulsification system S2:

[0092] S2.1, S2.2: same as Example 1, and the same pre-treatment solution was prepared.

[0093] S2.3: The pre-treatment solution was fed into a high-pressure homogenizer, and first homogenized 3 times at a pressure of 40 MPa, and then homogenized 2 times at a pressure of 90 MPa, to prepare a lycopene-loaded emulsion.

[0094] S2.4: Chopping operation was the same as Example 1.

[0095] 3. Molding and post-processing S3: the operation steps were completely consistent with Example 1.

[0096] <Comparative Example 3>

[0097] Comparative Example 3 differs from Example 1 in that the chopping speed is different, and is as follows:

[0098] 1. Preparation of base meat batter S1: the operation steps were completely consistent with Example 1.

[0099] 2. Construction of heat-induced protein-polysaccharide complex emulsification system S2:

[0100] S2.1, S2.2, S2.3: same as Example 1, and the same lycopene-loaded emulsion was prepared.

[0101] S2.4: The lycopene-loaded emulsion was added to the basic meat batter, and first chopped at a low frequency of 1200 rpm for 3 minutes, and then chopped at a high frequency of 3200 rpm for 4.5 minutes.

[0102] 3. S3 molding and post-processing: The operation steps were completely consistent with those of Example 1.

[0103] <Performance test>

[0104] 1. Oxidation stability test

[0105] Test method: The lipid oxidation index (TBARS value) was determined according to GB 5009.181-2016 "National Food Safety Standard Determination of Malondialdehyde in Food"; the protein oxidation index (carbonyl value) was determined by the 2,4-dinitrophenylhydrazine method (a mature detection method in the food industry).

[0106] Test sample: The meat products after frozen storage for 1 month in Examples 1-3 and Comparative Examples 1-3. The test results are shown in Table 1.

[0107] Table 1: Oxidation property test results of Examples 1-3 and Comparative Examples 1-3

[0108]

[0109] From the oxidation stability test data, the TBARS values of Examples 1-3 were all in the range of 0.32-0.35 mg / kg, and the carbonyl values were all in the range of 1.85-1.92 nmol / mg protein, both indicators remained at a low level, indicating that the degree of lipid oxidation and protein oxidation of the meat products during frozen storage was weak. By comparison, Comparative Example 1, due to the absence of heat-induced protein-polysaccharide complex emulsification system, directly added lycopene, which resulted in its inability to stably exert antioxidant effect, with a TBARS value of 0.87 mg / kg and a carbonyl value of 3.62 nmol / mg protein, which was significantly higher than that of the example group; the TBARS values of Comparative Examples 2 and 3 were 0.59 mg / kg and 0.55 mg / kg, respectively, and the carbonyl values were 2.78 nmol / mg protein and 2.65 nmol / mg protein, respectively, which were better than Comparative Example 1, but still significantly higher than Examples 1-3. This shows that the heat-induced protein-polysaccharide complex emulsification system can effectively improve the stability of lycopene, and the homogenization and chopping key parameters need to strictly meet the limited range, in order to fully inhibit the oxidation of meat products.

[0110] 2. Texture property test

[0111] Test method:

[0112] 1) Sample pretreatment: ① Thawing and equilibration: the frozen sample was taken out from -18℃, thawed at 4℃ for 12 hours, cut into cubes of 2cm x 2cm x 2cm (remove the surface fascia), and equilibrated at room temperature (25℃±1℃) for 30 minutes; ② Preparation of parallel samples: 3 parallel samples were prepared for each sample, and the mass deviation of each sample was ensured to be ≤0.5g.

[0113] 2) Texture analyzer parameter setting:

[0114] ① Probe selection: P / 50 cylindrical probe (diameter 50mm);

[0115] ② Test parameters: pre-test speed 2mm / s, test speed 1mm / s, post-test speed 1mm / s, compression ratio 50%, interval between two compressions 5 seconds, trigger force 5g;

[0116] ③ Data collection: record the elasticity (mm) and chewiness (N・mm) of each test. Take the average value of 3 parallel samples as the final result, and the relative deviation of parallel samples is ≤8% (when the deviation is out of limit, the sample is re-prepared for detection).

[0117] Test samples: the meat products thawed after being frozen for 1 month in Examples 1-3 and Comparative Examples 1-3. The test results are shown in Table 2.

[0118] Table 2: Texture property test results of Examples 1-3 and Comparative Examples 1-3

[0119]

[0120] In the texture property test, the elasticity of Examples 1-3 was in the range of 8.0-8.2mm, and the chewiness was in the range of 122-125N・mm, indicating that the meat products had good elasticity and moderate chewiness, and the eating taste was good. Comparative Example 1 had no heat-induced protein-polysaccharide complex emulsification system, and the emulsion gel network structure was loose, with an elasticity of only 5.3mm and a chewiness of 88N・mm, which was much lower than that of the example group; the elasticity of Comparative Example 2 was 6.8mm, and the chewiness was 105N・mm; the elasticity of Comparative Example 3 was 6.5mm, and the chewiness was 102N・mm; the texture of both was better than that of Comparative Example 1, but still could not reach the level of Examples 1-3. Therefore, by constructing a complex emulsification system and controlling the homogenization and chopping parameters, the emulsion gel network structure can be optimized, and the meat products can be given better texture properties. The absence of the key system or deviation from the key parameters will lead to texture deterioration.

[0121] 3. Lycopene dispersibility test

[0122] Detection method: Measurement was performed using an optical microscope (400x magnification, bright field light source) combined with Image-Pro Plus 6.0 software. The specific steps are as follows:

[0123] 1) Sample pretreatment: Cut the meat product into 8μm thick slices along the cross section, clear them with xylene, place them on a glass slide, add 1 drop of glycerol (refractive index 1.47) as a medium, and cover with a coverslip;

[0124] 2) Microscope calibration: Use a 1mm platform ruler to calibrate the eyepiece micrometer under 400x magnification, and record the actual length corresponding to each division;

[0125] 3) Image acquisition: Randomly select 15 fields of view (avoiding edge areas), adjust the exposure time until the grain boundaries are clear, and take images;

[0126] 4) Image analysis: In Image-Pro Plus, set the grayscale threshold to 120~180 (to distinguish lycopene from the background) and the roundness to ≥0.7 (to remove fiber impurities), and count the particle size of each field of view, counting a total of ≥500 particles;

[0127] 5) Result calculation: The number average particle size is used as the final result (the smaller the particle size, the more uniform the distribution, and the better the dispersibility). Three parallel samples are made for each sample, and the relative deviation of the parallel samples is ≤8%.

[0128] Test samples: cross-sectional slices of meat products from Examples 1-3 and Comparative Examples 1-3. Test results are shown in Table 3.

[0129] Table 3 shows the detection results of Examples 1-3 and Comparative Examples 1-3.

[0130]

[0131] The lycopene dispersibility test results showed that the average particle size of lycopene in Examples 1-3 was only 1.2-1.3 μm, with uniform particle distribution and no obvious agglomeration. This indicates that the heat-induced protein-polysaccharide composite emulsion system, along with homogenization and chopping processes, can effectively solve the problem of hydrophobic aggregation of lycopene. In Comparative Example 1, because the composite emulsion system was not constructed, lycopene was difficult to disperse in the minced meat after being directly mixed with lard, with an average particle size of 8.5 μm and severe agglomeration. The average particle sizes of lycopene in Comparative Examples 2 and 3 were 3.8 μm and 3.5 μm, respectively, which were improvements over Comparative Example 1, but the dispersion uniformity was still far lower than that of Examples 1-3. This shows that only by strictly following the process limitations of this technical solution can the uniform dispersion of lycopene in minced meat be achieved, laying the foundation for its antioxidant effect. Deviating from the process limitations will lead to a significant decrease in dispersibility.

[0132] In another technical solution, the homogenate obtained after homogenization at 100-150 MPa for 1-3 times in the step S2.3 is subjected to the following operations to prepare the lycopene-loaded emulsion: 0.05%-0.2% rosemary extract and 0.1%-0.3% β-sitosterol are added to the homogenate, and the mixture is stirred at 40-50°C and 3000-5000 rpm for 15-30 minutes, and then cooled to 4°C within 5 minutes and left to mature in a refrigeration device for 12-24 hours to obtain the lycopene-loaded emulsion.

[0133] In the above technical solution, when the meat product is processed, 0.05%-0.2% food-grade rosemary extract and 0.1%-0.3% food-grade β-sitosterol are added to the homogenate obtained after homogenization at 100-150 MPa for 1-3 times, and these materials are all existing food-grade raw materials that can be obtained from conventional food additive suppliers. Then the mixture is stirred at 40-50°C and 3000-5000 rpm for 15-30 minutes, and the stirring device can be a planetary stirrer. After stirring, the mixture is cooled to 4°C within 5 minutes and left to mature in a refrigeration device for 12-24 hours to obtain the lycopene-loaded emulsion.

[0134] The technical effect of this technical solution mainly lies in improving the stability of the lycopene-loaded emulsion and the oxidation resistance of the meat product, avoiding the rupture of the emulsion and the aggregation of lycopene during processing and storage, and reducing lipid and protein oxidation. The closest prior art is to dissolve lycopene in the oil phase for emulsification and dispersion, which forms an emulsion with a simple interface and poor stability, and the oil droplets are prone to aggregation during subsequent chopping and heating, resulting in uneven distribution of lycopene and poor antioxidant effect. However, the present technical solution constructs a composite interface layer by adding rosemary extract and β-sitosterol, which enhances the resistance of the emulsion to physical and oxidative stress. This improvement is not a simple addition of raw materials, but an optimization of the interface structure by utilizing the synergistic effect of the two components to solve the problem of insufficient stability of the emulsion in the prior art.

[0135] The technical effect of this technical solution is illustrated by specific examples and comparative examples as follows.

[0136] <Example 4>

[0137] Example 4 is based on Example 1, and the difference between Example 4 and Example 1 is that a post-treatment step of the homogenate is added, which is as follows:

[0138] 1. S1: Preparation of basic meat paste: same as Example 1.

[0139] 2. S2: Construction of heat-induced protein-polysaccharide complex emulsification system:

[0140] S2.1, same as example 1.

[0141] S2.2, same as example 1.

[0142] S2.3, the pretreated liquid is sent into a high-pressure homogenizer, first homogenized 3 times at a pressure of 65 MPa, each time homogenized for 2 minutes, then the pressure is adjusted to 125 MPa, and then homogenized 2 more times to obtain a homogenized liquid; 0.1% of food-grade rosemary extract and 0.2% of food-grade beta-sitosterol are added to the homogenized liquid, which accounts for 0.1% of the total mass of the homogenized liquid, and stirred at 45°C and 4000 rpm for 22 minutes, then quickly cooled to 4°C, and placed in a refrigerator for maturation for 18 hours to prepare a lycopene-loaded emulsion.

[0143] S2.4, same as example 1.

[0144] 3. S3 molding and post-processing: same as example 1.

[0145] <Comparative Example 4>

[0146] Comparative Example 4 differs from Example 4 in that the step of adding "rosemary extract + beta-sitosterol" is omitted, and the specific steps are as follows:

[0147] 1. S1 preparation of basic meat paste: the operation is completely consistent with Example 4.

[0148] 2. S2 construction of heat-induced protein-polysaccharide complex emulsification system:

[0149] S2.1, S2.2, the operation is consistent with Example 4.

[0150] S2.3, the pretreated liquid is sent into a high-pressure homogenizer, first homogenized 3 times at a pressure of 65 MPa, each time homogenized for 2 minutes, then the pressure is adjusted to 125 MPa, and then homogenized 2 more times to obtain a homogenized liquid; the step of adding "rosemary extract and beta-sitosterol" is omitted, and the homogenized liquid is directly cooled to 4°C, and placed in a refrigerator for maturation for 18 hours to prepare a lycopene-loaded emulsion.

[0151] S2.4, the operation is consistent with Example 4.

[0152] 3. S3 molding and post-processing: the operation is completely consistent with Example 4.

[0153] <Performance Test>

[0154] 1. Emulsion storage stability test

[0155] 1.1, centrifugal stability test (measuring oil separation rate):

[0156] 1) Sample preparation: Take 10 mL of emulsion (homogenized and equilibrated at room temperature for 30 minutes), slowly inject along the wall of the centrifuge tube (precision 0.1 mL), avoid generating bubbles;

[0157] 2) Centrifugation operation: Set the centrifuge speed to 3000 rpm, temperature to 25°C, centrifuge for 15 minutes, then take out, stand for 5 minutes to stabilize the interface;

[0158] 3) Oil separation rate calculation: Read the volume of the upper oil phase in the centrifuge tube (V1, mL), calculate according to the formula "oil separation rate = (V1 / 10 mL) x 100%", and take the average of 3 parallel samples for each sample.

[0159] 1.2, 4°C refrigeration stability observation:

[0160] 1) Sample placement: Take 20 mL of emulsion and fill it into a transparent sealed bottle, mark the initial liquid level, and place it in a 4°C refrigerator (humidity 60%);

[0161] 2) Regular observation: Take out at 1, 3, and 7 days of refrigeration, equilibrate at room temperature for 10 minutes, then observe and record "whether it is layered", "oil layer thickness ratio", and "interface clarity" (layering degree is classified as "no layering / slight layering (oil layer <5%) / obvious layering (oil layer ≥5%)");

[0162] 3) Result determination: Combine the oil separation rate (≤5% is qualified) and the refrigeration layering situation to determine the storage stability of the emulsion (the lower the oil separation rate and the less the refrigeration layering, the better the stability)

[0163] 1.3, Detection sample: Detect the above properties of the lycopene-loaded emulsion prepared in Example 4 and Comparative Example 4. The detection results are shown in Table 4.

[0164] Table 4 Detection results of Example 4 and Comparative Example 4

[0165]

[0166] From the detection results, it can be seen that the centrifugal oil separation rate of the emulsion of Example 4 is only 1.2%, and there is no obvious layering after 7 days of refrigeration at 4°C, and the system remains uniform; while the centrifugal oil separation rate of the emulsion of Comparative Example 4 is as high as 5.8%, and slight layering and a small amount of oil phase are separated after 7 days of refrigeration. This shows that the addition of rosemary extract and β-sitosterol can significantly improve the storage stability of lycopene-loaded emulsion - rosemary extract can inhibit lipid oxidation in emulsion, β-sitosterol can optimize the interface structure of emulsion and reduce oil phase separation, and the synergistic effect of the two can make the emulsion remain stable under centrifugal and low-temperature storage conditions, while the absence of this step in Comparative Example 4 cannot achieve this effect.

[0167] 2. Oxidative stability test of frozen meat products

[0168] The TBARS value and carbonyl value of the meat products after being frozen for 3 months in Example 4, Comparative Example 4 and Example 1 were detected. The results are shown in Table 5.

[0169] Table 5. Results of oxidative stability test

[0170]

[0171] Conclusion: After being frozen for 3 months, the TBARS value and carbonyl value of Example 4 were significantly lower than those of Comparative Example 4 and Example 1, and the data of the three were obviously different. This shows that the addition of rosemary extract and β-sitosterol can effectively enhance the oxidative stability of frozen meat products: the antioxidant activity of rosemary extract can inhibit the production of malondialdehyde (reduce the TBARS value) and reduce the protein carbonylation reaction (reduce the carbonyl value) during lipid oxidation. However, Comparative Example 4 lacks this improvement, and Example 1 does not add relevant ingredients, so they cannot effectively inhibit the oxidation reaction during freezing, resulting in significantly higher oxidation indicators.

[0172] 3. Lycopene retention rate test

[0173] Test method:

[0174] 1) Sample pretreatment: ① Sample homogenization: take the frozen meat products frozen for 3 months, thaw at 4°C, grind, homogenize with a high-speed homogenizer (10000 rpm) for 2 minutes, and weigh 5.00g of homogenized sample into a 50mL centrifuge tube; ② Saponification and degreasing: add 10mL of potassium hydroxide-ethanol solution (10% by mass), mix well after vortexing, and saponify at 60°C for 30 minutes, vortexing every 10 minutes during the period; ③ Extraction: cool to room temperature, add 15mL of n-hexane-acetone mixed solvent (volume ratio 2:1), vortex for 5 minutes, centrifuge at 3000 rpm for 10 minutes, and collect the upper organic phase; repeat the extraction 3 times, and combine all the organic phases into a 50mL volumetric flask and dilute to the mark with n-hexane; ④ Purification: take 10mL of the extract through a silica gel solid phase extraction (SPE) column (500mg / 6mL), elute with 5mL of n-hexane-dichloromethane (volume ratio 9:1), collect the eluate, filter through a 0.22μm organic phase filter membrane, and test.

[0175] 2) HPLC detection: ① chromatographic conditions: the chromatographic column is C18 column (250 mm x 4.6 mm, 5 μm), the column temperature is 30℃; the mobile phase is methanol-acetonitrile-dichloromethane (volume ratio 60:30:10), the flow rate is 1.0 mL / min; the detection wavelength is 472 nm, the injection amount is 20 μL; ② standard curve drawing: prepare lycopene standard solution (concentration 0.1, 0.5, 1.0, 5.0, 10.0 μg / mL), sample injection and determination of peak area, with concentration as abscissa and peak area as ordinate to draw standard curve (R 2 ≥0.999); ③ sample determination: record the peak area of the sample to be tested, and calculate the lycopene content (unit: mg / kg) by substituting the standard curve.

[0176] 3) retention rate calculation: retention rate = (lycopene content after frozen storage / initial addition amount) x 100%; 3 parallel samples are prepared for each sample, and the average value is taken as the final result.

[0177] Test samples: meat products after frozen storage for 3 months in Example 4, Comparative Example 4 and Example 1. The results are shown in Table 6.

[0178] Table 6: Lycopene retention rate test results

[0179]

[0180] Experimental conclusion: after frozen storage for 3 months, the lycopene retention rate of Example 4 is 82.5%, while the retention rates of Comparative Example 4 and Example 1 are only 61.3% and 60.8% respectively, and the retention effect of Example 4 is significantly better. This difference is due to the synergistic effect of rosemary extract and β-sitosterol: rosemary extract can inhibit the oxidative degradation of lycopene during frozen storage, and β-sitosterol can stabilize the emulsion interface and reduce the loss of lycopene due to oil phase separation, and the combined action of the two can keep lycopene at a high retention rate after long-term frozen storage; Comparative Example 4 lacks this step, and Example 1 has no related ingredients for protection, resulting in easy oxidative degradation and loss of lycopene, and a significant reduction in retention rate.

[0181] In another technical solution, after the cooking and setting step S3, a quality maintenance agent soaking step S3.1 is further included, specifically as follows: after the cooked and set meat product is immersed in a quality maintenance agent solution at 4-8℃ for 30-60 minutes, it is taken out and then drained, and then packaged and frozen; the quality maintenance agent solution is an aqueous solution containing 1%-3% trehalose and 0.5%-1.5% konjac glucomannan.

[0182] In the above technical solution, after the cooking and setting, the meat product is immersed in the solution, the soaking temperature is controlled at 4-8℃, the soaking time is 30-60 minutes, and the soaking equipment can be selected as a soaking tank with temperature control function; after soaking, the meat product is taken out and the surface moisture is drained.

[0183] The technical effect of this technical solution is to reduce the ice crystal damage in the frozen storage process of meat products, reduce the thawing liquid loss rate, and maintain the tender texture. The closest prior art is to directly cool and freeze the cooked meat products, and the ice crystals easily damage the protein gel network during the freezing process, resulting in more liquid loss after thawing and dry taste. This technical solution inhibits the growth of ice crystals and protects the gel network through the synergistic effect of trehalose and konjac glucomannan. This improvement targets the industry pain point of frozen meat products, and is not simply using a single quality maintenance agent, but using the complementary effect of two components to improve the quality, solving the problem that the existing technology cannot effectively maintain the quality of frozen meat products.

[0184] The beneficial effects of the technical solution will be illustrated by specific examples as follows.

[0185] <Example 5>

[0186] Example 5 is based on Example 1 and is as follows:

[0187] 1. S1: Prepare the basic meat paste: the operation is completely consistent with Example 1.

[0188] 2. S2: Construct a heat-induced protein-polymer complex emulsion system: the operation is completely consistent with Example 1.

[0189] 3. S3: Forming, cooking and setting, and quality maintenance agent soaking:

[0190] Forming and cooking and setting: pour the chopped and mixed meat paste into a 10cm×5cm×3cm stainless steel mold and press it into shape, then put it into an 82℃ hot water boiler to cook for 25 minutes to complete the setting;

[0191] Quality maintenance agent soaking: Prepare quality maintenance agent solution - take food-grade trehalose, food-grade konjac glucomannan, add purified water, stir until completely dissolved, trehalose accounts for 1.5% of the total mass of the aqueous solution, konjac glucomannan accounts for 1.0% of the total mass of the aqueous solution; remove the shaped meat product from the mold, immerse it in the quality maintenance agent solution, and remove it after 45 minutes of soaking in a 6°C temperature-controlled soaking tank, and drain the surface moisture;

[0192] Packaging and frozen storage: Package the drained meat product with food-grade polyethylene film and store it in a -18°C freezer.

[0193] II. Performance testing

[0194] 1. Meat product thawing juice loss rate detection

[0195] Detection method:

[0196] 1) Sample pretreatment: ① Frozen sample preparation: select frozen meat products for 3 months, remove surface damaged samples, cut into 5cm x 5cm x 2cm cuboids (3 parallel samples per group, each sample weighs about 50g), weigh the initial mass of each sample with an analytical balance (accuracy 0.01g), and record it as m1; ② Thawing operation: place the sample in a 4°C±1°C refrigerator (humidity 60%±5%), and avoid stacking the sample during the 12-hour thawing period (ensure uniform thawing).

[0197] 2) Juice absorption and weighing: ① Absorption treatment: after thawing, remove the sample and press the surface of the sample with a quantitative filter paper (medium speed, diameter 11cm) (press for 10 seconds each time, a total of 3 times), and absorb the surface attached juice (avoid squeezing the internal sample); ② Second weighing: immediately weigh the mass of the sample after absorbing the moisture with the same analytical balance, and record it as m2.

[0198] 3) Loss rate calculation: Juice loss rate = (m1-m2) / m1 x 100%; take the average value of 3 parallel samples of each sample as the final result, and the relative deviation of the parallel samples is ≤5% (if the deviation exceeds the limit, the sample needs to be reselected and retested).

[0199] Detection sample: frozen meat products for 3 months in Example 5 and Example 1. The detection results are shown in Table 7.

[0200] Table 7 Thawing juice loss rate detection results

[0201]

[0202] The thawing juice loss rate in Example 5 was only 3.2%, significantly lower than the 7.8% in Example 1. This indicates that the quality-preserving agent soaking step can effectively reduce juice loss after frozen storage of meat products—trehalose can reduce water loss by binding with proteins, and konjac glucomannan can form a protective film on the surface of meat products, with the two working together to lock in internal moisture; while in Example 1, because this step was missing, ice crystals easily destroyed the gel network structure of meat products during frozen storage, resulting in a large amount of juice loss during thawing, further proving the necessity of this step in improving the water retention of meat products.

[0203] 2. Detection of textural properties of meat products after frozen storage

[0204] Detection method: Same as described above.

[0205] Test samples: Meat products from Examples 5 and 1 that were frozen for 3 months and then thawed. Test results are shown in Table 8.

[0206] Table 8. Results of Texture Properties Test

[0207]

[0208] Table 8 shows that after 3 months of frozen storage, the elasticity and chewiness of Example 5 were higher than those of Example 1, while the hardness was lower. This indicates that the trehalose and konjac glucomannan in the quality preservation agent can protect the gel network structure of meat products during frozen storage, reduce the damage of ice crystals to the protein network, thereby maintaining good elasticity and chewiness, while avoiding excessive hardness leading to a dry texture. Example 1, lacking the protection of the quality preservation agent, suffered more severe damage to its gel network during frozen storage, resulting in a significant deterioration in its textural properties. This verifies the crucial role of the added step in this technical solution in maintaining the texture of meat products.

[0209] In another technical solution, after standing and maturing for 12-24 hours in step S2.3, a standing liquid is obtained. The standing liquid is then subjected to the following operation to prepare a lycopene-loaded emulsion: the standing liquid is mixed with an equal volume of papain solution and incubated at 37°C and pH 7.0 with shaking at 100-150 rpm for 20-40 minutes. Subsequently, the mixture is heated at 85°C for 5 minutes to inactivate the enzyme, and then cooled to below 4°C within 5 minutes to obtain the lycopene-loaded emulsion. The papain solution has an enzyme activity of 500-2000 U / mL.

[0210] In the above technical solution, after obtaining the standing liquid, papain solution is prepared first, the enzyme source is food-grade papain powder, the solvent is pure water, and the enzyme activity is adjusted to 500-2000 U / mL. For example, when 10000 U / g of papain powder is dissolved in water to prepare a 500 U / mL solution, 0.05 g of enzyme powder can be added to every 100 mL of water, and the enzyme activity is calibrated by an enzyme activity determination kit. An equal volume of the papain solution to the standing liquid is measured, and both are added to the shaking incubation equipment. The shaking incubation equipment can be a constant temperature shaking incubator, and the incubation temperature is set to 37°C, pH 7.0 (adjusted by food-grade citric acid or sodium hydroxide solution), the shaking speed is 100-150 rpm, and the incubation time is 20-40 minutes. For example, the speed can be set to 120 rpm and the incubation time to 30 minutes. After incubation, the mixed liquid is transferred to a constant temperature water bath equipment, heated at 85°C for 5 minutes to inactivate the enzyme, and then cooled to below 4°C within 5 minutes. The cooling method can be an ice water bath, and finally the lycopene-loaded emulsion is obtained.

[0211] The technical effects of the present technical solution mainly include three aspects: first, the moderate enzymatic hydrolysis of papain can mildly hydrolyze the proteins in the emulsion, destroy part of the tight protein network structure, make lycopene more easily maintain a dispersed state during subsequent processing and storage, reduce aggregation, and create favorable conditions for its release during digestion; second, the emulsion treated by enzymolysis has stronger oil droplet stability and is less likely to break and aggregate during the mixing and chopping of meat paste and subsequent freezing and storage, which helps to maintain the uniformity of the internal structure of meat products; third, after enzymolysis, lycopene can be more efficiently released from the carrier during human gastrointestinal digestion, more easily absorbed by the human body, and its antioxidant activity can also be better preserved, thereby improving the nutritional value of meat products while better exerting its antioxidant effect and delaying the quality deterioration of meat products during storage. By controlling the enzyme activity, pH, temperature and time of papain, moderate hydrolysis of the emulsion interface protein can be achieved without excessive damage to the stability of the emulsion, and the digestion and release characteristics of lycopene can be improved.

[0212] The technical effects of the present technical solution are illustrated by specific examples as follows.

[0213] <Example 6>

[0214] Example 6 is based on Example 4 and is implemented as follows:

[0215] 1. Preparation of basic meat paste S1: consistent with Example 4.

[0216] 2. Construction of heat-induced protein-polysaccharide complex emulsification system S2:

[0217] S2.1, S2.2, S2.3 Pre-ripening standing operation: consistent with Example 4, i.e. prepare a 4% soy protein isolate solution and heat at 90°C for 30 minutes, after cooling, add lycopene, melted lard, inulin to prepare a pretreatment liquid, after homogenization, add rosemary extract and β-sitosterol and stir, cool to 4°C and stand for 18 hours to obtain a standing liquid.

[0218] S2.3 Subsequent treatment of standing liquid: prepare a food-grade papain solution with an enzyme activity of 1000 U / mL; measure an equal volume of papain solution as the standing liquid, and add both to a constant temperature shaking incubator, set to 37°C, pH 7.0, shaking speed 120 rpm, and shake for 30 minutes; after incubation, transfer the mixed liquid to a constant temperature water bath, heat at 85°C for 5 minutes to inactivate the enzyme, and then quickly cool to below 4°C to obtain a lycopene-loaded emulsion. The food-grade papain solution with an enzyme activity of 1000 U / mL is prepared as follows: according to the labeled enzyme activity of the commercial food-grade papain powder (e.g. 10000 U / g), calculate and weigh, dissolve in pure water and dilute to the required volume to obtain a solution with a concentration of 1000 U / mL.

[0219] S2.4 Chopping and mixing: consistent with Example 4.

[0220] 3. S3 Forming and post-processing: consistent with Example 4.

[0221] II. Performance testing

[0222] 1. Lycopene bioavailability testing

[0223] Testing method:

[0224] 1) Sample pretreatment: ① Take the frozen and stored meat products for 3 months, and homogenize at high speed (10000 rpm, 2 minutes) after thawing at 4°C, weigh 2.00g of homogenized sample into a 50mL centrifuge tube as the sample to be tested; ② Determine the "total lycopene content before digestion" (denoted as Ctotal) according to GB / T 22249-2024 "Determination of Lycopene in Health Food": after saponification, n-hexane extraction, SPE purification, HPLC quantification, it is used as the calculation reference.

[0225] 2) In vitro digestion simulation: ① Oral digestion: 10 mL of simulated saliva solution (containing α-amylase 150 U / mL, pH 6.8, preheated at 37℃) was added to the sample, and the reaction was carried out at 37℃ with 100 rpm shaking for 2 minutes; ② Gastric digestion: 15 mL of simulated gastric juice solution (containing pepsin 2000 U / mL, hydrochloric acid to adjust pH 2.0, preheated at 37℃) was added, and the reaction was carried out at 37℃ with 100 rpm shaking for 2 hours; ③ Intestinal digestion: 20 mL of simulated intestinal juice solution (containing trypsin 100 U / mL, bile salt 10 mmol / L, NaOH to adjust pH 7.0, preheated at 37℃) was added, and the reaction was carried out at 37℃ with 150 rpm shaking for 4 hours under nitrogen protection (to prevent lycopene oxidation).

[0226] 3) Absorbable lycopene separation and quantification: ① Micellar phase separation: after digestion, centrifuge at 3000 rpm for 30 minutes, take the upper clear liquid (absorbable micellar phase), and filter through a 0.22 μm organic phase filter membrane; ② HPLC quantification: refer to the chromatographic conditions of GB / T22249-2024, and determine the lycopene content in the solution after the filter membrane (denoted as Cabsorbable).

[0227] 4) Bioaccessibility calculation: Bioaccessibility = (Cabsorbable / Ctotal) x 100%; each sample was prepared in triplicate, the relative deviation of the parallel samples was ≤10%, and the average value was taken as the final result.

[0228] Test samples: meat products after 3 months of frozen storage in Example 6 and Example 4. The test results are shown in Table 9.

[0229] Table 9 Lycopene bioaccessibility test results

[0230]

[0231] The lycopene bioaccessibility of Example 6 was significantly higher than that of Example 4, which indicated that the newly added "papain enzymolysis step" could effectively improve the bioaccessibility of lycopene - papain could moderately hydrolyze the proteins in the emulsion, destroy part of the protein network structure, and make it easier for lycopene to be released from the carrier and form absorbable micelles during in vitro digestion; without enzymolysis treatment in Example 4, the protein network structure was tight, and the release of lycopene was blocked, resulting in a significant reduction in bioaccessibility, which fully proved the key role of this step in optimizing the nutritional utilization efficiency of lycopene.

[0232] 2. Antioxidant activity detection after in vitro digestion of meat products

[0233] Detection method:

[0234] 1) Sample pretreatment (digestion solution preparation): ① Take the supernatant (absorbable micellar phase) after intestinal digestion in "Lycopene Bioavailability Detection", centrifuge at 3000 rpm for 10 minutes, dilute the supernatant 5 times with anhydrous ethanol, filter through a 0.22 μm organic phase filter, and use as the sample solution to be tested; ② Blank solution preparation: take "blank meat product without lycopene" (other processes are consistent with the corresponding examples), prepare "blank digestion solution" according to the same in vitro digestion process, dilute 5 times and filter, and use as the sample blank solution.

[0235] 2) DPPH solution preparation: accurately weigh 12.4 mg of DPPH reagent, dissolve and dilute to 250 mL with anhydrous ethanol to prepare a 0.1 mmol / L DPPH solution; store in the dark (4°C) and equilibrate at room temperature for 30 minutes before use. The absorbance at 517 nm is calibrated to 0.70±0.02 using a UV spectrophotometer.

[0236] 3) Reaction and determination: ① Reaction system: take 2 mL of the sample solution to be tested, add 2 mL of DPPH solution (volume ratio 1:1), mix well, and avoid light for 30 minutes (25°C±1°C); ② Blank control: set up 3 groups of blanks — solvent blank (2 mL of anhydrous ethanol + 2 mL of DPPH solution), DPPH blank (2 mL of anhydrous ethanol + 2 mL of DPPH solution, same as solvent blank), and sample blank (2 mL of sample blank solution + 2 mL of anhydrous ethanol); ③ Absorbance determination: use a UV spectrophotometer to measure the absorbance at 517 nm, and record it as A sample (sample solution + DPPH), A sample blank (sample blank solution + ethanol), and A blank (solvent blank).

[0237] 4) Clearance calculation: DPPH free radical clearance = [1- (A sample - A sample blank) / A blank] x 100%; each sample is tested in triplicate, with a relative deviation of ≤8% for the parallel samples, and the average value is taken as the final result (the higher the clearance, the stronger the antioxidant activity of the released lycopene).

[0238] Test sample: the supernatant after intestinal digestion in "Lycopene Bioavailability Detection" of the meat products in Example 6 and Example 4 after being frozen and stored for 3 months. The test results are shown in Table 10.

[0239] Table 10 Test results

[0240]

[0241] The DPPH radical scavenging rate of the digestive juice of Example 6 is significantly higher than that of Example 4. This is because the enzymatic step not only increases the amount of lycopene released, but also reduces the shielding of the lycopene antioxidant site by proteins, allowing the released lycopene to more effectively bind to free radicals; the antioxidant activity of Example 4 is weak due to insufficient release of lycopene and partial shielding of the active site. This result further demonstrates that the process improvement of the enzymatic step can improve the bioavailability of lycopene while ensuring the effective exertion of its antioxidant function.

[0242] In another technical solution, the S1 step specifically comprises:

[0243] S1.1, pre-hydration: mixing the composite flavor carrier with a portion of ice water accounting for 20%-40% of the total ice water, stirring until completely dissolved and dispersed to form a flavor carrier solution; the composite flavor carrier contains 0.5%-1% yeast extract, 0.2%-0.5% mushroom powder, and 0.5%-1% modified citrus fiber, with the balance being food-grade carrier;

[0244] S1.2, chopping and extracting: chopping fresh meat, mixing with 2.0% of the meat mass of salt, 0.2%-0.3% of the meat mass of sodium tripolyphosphate, the flavor carrier solution, and the remaining ice water at 4-8°C to form the base meat paste;

[0245] wherein the total amount of the composite flavor carrier added accounts for 3%-6% of the total mass of the base meat paste; the modified citrus fiber is prepared by high-pressure homogenization of citrus fiber to dissociate the fiber bundles.

[0246] In the above technical solution, when processing meat products, the operation of preparing the meat paste in S1 is first carried out, which is divided into two parts: pre-hydration and chopping and extraction. In the pre-hydration stage, the composite flavor carrier can be mixed with a portion of ice water accounting for 20%-40% of the total ice water, and the total amount of the composite flavor carrier added can account for 3%-6% of the total mass of the meat paste. The carrier can contain 0.5%-1% yeast extract, 0.2%-0.5% mushroom powder, and 0.5%-1% modified citrus fiber, and the balance can be food-grade malt dextrin as the carrier. These materials are all conventional food raw materials available on the market. The total amount of ice water is calculated based on 20% of the meat mass, and in this embodiment, 30% of the total ice water can be selected for pre-hydration. The composite flavor carrier and the portion of ice water are added to a stirring tank, and at room temperature, a conventional stirring device can be used to stir at a speed of 800 rpm for 15 minutes until the composite flavor carrier is completely dissolved and dispersed to form a flavor carrier solution. The modified citrus fiber can be treated by a high-pressure homogenization device available on the market, and the citrus fiber can be homogenized at a pressure of 80 MPa for 2 times to dissociate the fiber bundles and obtain the modified citrus fiber.

[0247] Then, chopping and extraction is carried out, the fresh meat is ground and sent into a chopping device, 2.0% of salt by mass of the meat, 0.2%-0.3% of sodium tripolyphosphate by mass of the meat, the flavor carrier solution prepared above and the remaining ice water are added into the chopping device, the temperature of the ice water is controlled at 4-8℃, the chopping environment temperature is controlled at 4-8℃, the chopping device is started to chop at a speed of 1800 rpm for 8 minutes, so that the components are uniformly mixed with the meat paste, and finally a stable salt-soluble protein extraction system is formed, and the basic meat paste is obtained.

[0248] During the whole implementation process, by optimizing the S1 step, a composite flavor carrier containing yeast extract, mushroom powder and modified citrus fiber is introduced, wherein the yeast extract and the mushroom powder can synergistically improve the umami taste and meaty richness of the meat product and mask the possible undesirable flavors of the functional components; the modified citrus fiber can enhance the water holding capacity of the basic meat paste, reduce the loss of juice, and at the same time assist in improving the texture, so that the meat product can still maintain good sensory quality and edible taste after frozen storage.

[0249] The technical effects of the technical scheme are illustrated below through specific examples.

[0250] <Example 7>

[0251] 1. S1 preparation of basic meat paste:

[0252] S1.1 pre-hydration: the composite flavor carrier is mixed with 30% of 6℃ ice water of the total amount of ice water, added into a stirring tank, and stirred at 800 rpm for 15 minutes until completely dissolved to form a flavor carrier solution; the composite flavor carrier contains 0.8% of yeast extract, 0.3% of mushroom powder and 0.7% of modified citrus fiber, and the balance is food-grade malt dextrin; wherein the modified citrus fiber is obtained by dissociating the fiber bundle twice at a high pressure of 80 MPa.

[0253] S1.2 chopping and extraction: fresh pork is selected, ground by a meat grinder, 2.0% of salt by mass of the meat, 0.25% of sodium tripolyphosphate by mass of the meat and the remaining ice water are added, and the above materials are put into a chopping machine, and chopped for 8 minutes at an environment temperature of 6℃ to form a uniform salt-soluble protein extraction system, which is the basic meat paste. The total amount of the composite flavor carrier accounts for 4% of the total mass of the basic meat paste.

[0254] 2. S2 construction of heat-induced protein-polysaccharide composite emulsification system: the same as example 1.

[0255] 3. S3 molding and post-processing: the same as example 1.

[0256] II. Performance detection

[0257] 1. Meat product flavor score detection

[0258] The flavor of Example 7 is significantly higher than that of Example 1, especially in umami and meaty richness. This shows that the composite flavor carrier can effectively optimize the flavor - the synergistic effect of yeast extract and mushroom powder enhances the umami of meat products and improves the level of meaty flavor.

[0259] 2. Water holding capacity of meat products

[0260] Detection method: centrifugal method, cut the frozen meat products after 3 months into 10g small pieces, centrifuge at 3000rpm for 15 minutes, calculate the percentage of mass difference before and after centrifugation to initial mass (juice loss rate), and at the same time, measure the cooking loss rate of meat products (percentage of mass difference before and after cooking to initial mass).

[0261] Test sample: meat products after 3 months of frozen storage in Example 7 and Example 1. The test results are shown in Table 11.

[0262] Table 11 test results

[0263]

[0264] The centrifugal juice loss rate and cooking loss rate of Example 7 are lower than those of Example 1. This is because the modified citrus fiber in the composite flavor carrier is dissociated into fine components after high-pressure homogenization, which can form a physical barrier in the meat paste to prevent water loss; at the same time, its hydrophilic group can combine with part of the free water to improve the water holding capacity; Example has no such fiber effect, and water is easy to lose in the process of centrifugation and cooking, which proves the effectiveness of the composite flavor carrier in improving the water holding capacity.

[0265] In another technical solution, the chopping in step S2.4 is carried out in a chopping system with online viscosity feedback control. The chopping process specifically includes: S6.1, monitoring the apparent viscosity of the meat paste in real time in the low-frequency chopping stage; S6.2, when the apparent viscosity reaches a first preset threshold η1, the system automatically switches to the high-frequency chopping stage; S6.3, in the high-frequency chopping stage, the apparent viscosity of the meat paste is continuously monitored, and when the rising rate is lower than a second preset threshold Δη / Δt, the system determines that the conformation editing is completed, and automatically stops chopping.

[0266] In the above technical solution, when processing meat products, the meat paste preparation of S1 step and the preparation of lycopene-loaded emulsion of S2.1 to S2.3 in S2 step are first completed, and then the chopping operation of S2.4 is entered. The chopping operation can be carried out in a chopping system with online viscosity feedback control. The system can include a planetary chopper, an online viscosity sensor, and an automatic speed control module. These devices are all commercially available off-the-shelf devices. The online viscosity sensor can be installed on the inner wall of the stirring cavity of the chopper to ensure real-time contact and monitoring of the meat paste. The automatic speed control module can be integrated into the control system of the chopper to facilitate speed adjustment in conjunction with sensor data. Fresh meat used for meat paste preparation can be pork, beef, or chicken. Food-grade soy protein isolate, lycopene, melted pork fat, and food-grade inulin required for the preparation of lycopene-loaded emulsion can be obtained from conventional food raw material suppliers. These materials are commonly used in the existing food processing field.

[0267] After starting the chopping system, the prepared lycopene-loaded emulsion is added to the meat paste prepared in S1 step, and then the planetary chopper is started at a low frequency speed of 1800 rpm. The online viscosity sensor is started at the same time to monitor the apparent viscosity of the meat paste in real time, and the monitored viscosity data is continuously transmitted to the automatic speed control module. Due to differences in the composition of different meat raw materials (such as protein content and fat content), and differences in the performance of different types of chopping equipment (such as stirring intensity and cavity structure), the first preset threshold η1 needs to be calibrated for specific raw materials and chopping equipment through pre-experiments. During the pre-experiment, the viscosity data of the meat paste is collected every 30 seconds during the low-frequency chopping stage, and the appearance of the meat paste is observed. When the viscosity data no longer increases rapidly and the meat paste appears uniform and fine without obvious emulsion particles, it is determined that the salt-soluble protein is fully extracted and preliminarily mixed evenly with the emulsion, and the viscosity at this time is recorded as η1. For the planetary chopper and fresh pork raw material used in this embodiment, η1 is usually in the range of 4000-6000 mPa・s, and is preferably set to 5000 mPa・s. When the real-time apparent viscosity received by the automatic speed control module reaches 5000 mPa・s, the system automatically switches the speed of the chopper to the high-frequency stage, and the high-frequency chopping speed can be selected as 4000 rpm. The specific η1 is determined by designing experiments according to the actual situation.

[0268] In the high-frequency chopping stage, the online viscosity sensor continues to monitor the apparent viscosity of the meat paste in real time, and the automatic speed control module calculates the viscosity rise rate Δη / Δt in real time according to the continuously monitored viscosity data. Similar to η1, the second preset threshold Δη / Δt also needs to be calibrated for specific raw materials and chopping equipment through pre-experiments. During the pre-experiment, the viscosity data is collected every 30 seconds in the high-frequency chopping stage, and the difference between the adjacent two data (i.e. the viscosity change rate) is calculated. When the viscosity change rate calculated for three consecutive times is less than 10 mPa・s / min, and the meat paste is compact and stops flowing, it is determined that the gel network tends to be stable and the viscosity growth is gentle, and the average value of the change rate of the three times is taken as Δη / Δt. For the planetary chopping machine and fresh pork raw materials selected in this embodiment, Δη / Δt is usually in the range of 40-60 mPa・s / min, and is preferably set to 50 mPa・s / min. When the viscosity rise rate calculated by the automatic speed control module is less than 50 mPa・s / min, the system determines that the conformation editing of the meat paste is completed, and automatically controls the chopping machine to stop running, thereby completing the entire chopping process. The specific Δη / Δt is determined by designing experiments according to the actual situation.

[0269] In terms of function verification, three batches of fresh pork can be selected for chopping operation according to the above steps, each batch of experiment is repeated three times, the time points of stage switching in each chopping process and the viscosity state of the final meat paste are recorded, and the consistency between different batches is observed by combining the subsequent texture detection (such as elasticity, chewiness) of meat products, so as to verify the stability of the chopping control mode.

[0270] The technical effect of the technical solution is that the online viscosity feedback control realizes the automatic adjustment of the chopping process, does not need to rely on manual experience judgment, can accurately capture the state change of the meat paste in different chopping stages, and effectively reduces the quality difference between batches caused by manual operation differences or small fluctuations of raw materials and equipment. At the same time, the threshold calibrated for specific raw materials and equipment ensures the adaptability of the chopping control, which can help to form a stable composite gel network, and provides a basis for maintaining good texture and oxidation stability of subsequent meat products. Compared with the closest prior art (which relies on manual experience to control chopping time and speed), this method avoids the subjectivity and instability of manual judgment, can more reliably reproduce the best chopping effect, and improves the consistency and controllability of meat product processing.

[0271] In another technical solution, after the cooling in S3, a Maillard reaction substrate and a heat-induced gel coating step are further included, which is specifically as follows:

[0272] S7.1, preparing a coating liquid: the coating liquid comprises pea protein hydrolysate with a mass concentration of 3%-6%, D-ribose with a mass concentration of 1%-2%, sodium alginate with a mass concentration of 0.5%-1.5%, and potato starch with a mass concentration of 1%-3%, and the balance is water;

[0273] S7.2, immersing the cooked and shaped meat paste after cooling in the coating liquid, taking it out after 5-15 seconds, and forming a uniform thin layer;

[0274] S7.3, placing the coated meat paste in an environment with a temperature of 85-95°C and a humidity of 70%-80%, and hot air treating it for 8-15 minutes to make the coating pre-gelatinize and cook, and then freezing and storing it.

[0275] In the above technical solution, after the meat product is cooked and shaped, it is naturally cooled to room temperature, and then enters the step of Maillard reaction substrate and heat-induced gel coating.

[0276] First, a coating liquid is prepared, which can be prepared by using food-grade pea protein hydrolysate, D-ribose, sodium alginate, potato starch, and water as raw materials. The pea protein hydrolysate can account for 3%-6% of the total mass of the coating liquid, the D-ribose can account for 1%-2%, the sodium alginate can account for 0.5%-1.5%, the potato starch can account for 1%-3%, and the balance is pure water. These raw materials are sequentially added to a stirring tank, and a conventional stirring device is used to stir at a room temperature and a speed of 1000 rpm for 20 minutes until all the raw materials are completely dissolved to form a uniform and particle-free coating liquid. The pea protein hydrolysate can be obtained by a conventional method in the art, for example: preparing a 5%-10% aqueous solution of pea protein, adjusting the pH to 7.0-8.0, adding neutral protease or flavor protease (the addition amount is 1%-3% of the mass of the substrate) at 50-60°C, and enzymatically hydrolyzing for 1-3 hours. Then, the enzyme is inactivated by heating at 85°C or above for 10-15 minutes, and then spray drying to obtain a powdered hydrolysate.

[0277] Then, coating and cooking treatment is performed. The cooled meat product is immersed in the prepared coating liquid (the meat product is completely immersed in the coating liquid), and the immersion time can be selected within the range of 5-15 seconds to ensure that a uniform thin layer is formed on the surface of the meat product. After taking it out, it is transferred to a hot air drying device, the temperature in the device can be controlled at 85-95°C, the humidity can be controlled at 70%-80%, and the hot air treatment time can be selected within the range of 8-15 minutes to make the coating pre-gelatinize and cook. After the treatment is completed, the meat product is naturally cooled to room temperature, then packaged with food-grade packaging materials, and finally placed in a freezing device below -18°C for freezing and storage, completing the entire processing flow.

[0278] Through the above operation, the pea protein hydrolysate and D-ribose in the coating liquid can undergo Maillard reaction during hot air treatment and subsequent terminal cooking, improving the flavor and color of the meat product. The gel layer formed by sodium alginate and potato starch can reduce the loss of internal juice of the meat product during processing and storage. These effects are significantly improved compared with the meat product without coating treatment.

[0279] The technical effects of the technical solution are illustrated below through specific examples.

[0280] <Example 8>

[0281] 1. Preparation of basic meat paste S1: consistent with Example 1.

[0282] 2. Construction of heat-induced protein-polysaccharide complex emulsifying system S2: consistent with Example 1.

[0283] 3. S3 molding, cooking, and coating treatment:

[0284] Molding and cooking: consistent with Example 1.

[0285] Maillard reaction substrate and heat-induced gel coating:

[0286] S7.1 Preparation of coating liquid: weigh 4.5% pea protein hydrolysate (based on the total mass of the coating liquid), 1.5% D-ribose, 1.0% sodium alginate, and 2% potato starch, add the remaining amount of pure water, and stir at room temperature for 15 minutes with a stirrer until completely dissolved to form a uniform coating liquid. The preparation of the pea protein hydrolysate is as follows: prepare a 8% aqueous solution of pea protein, adjust the pH to 7.5, add neutral protease (addition amount is 2% of the mass of the substrate) at 55°C, and enzymatically hydrolyze for 1-3 hours. Then, heat sterilize at 85°C or above for 10-15 minutes to inactivate the enzyme, and then spray dry to obtain a powdered hydrolysate.

[0287] S7.2 Coating: immerse the cooled meat product in the coating liquid, and take it out after 10 seconds to form a uniform thin layer on the surface.

[0288] S7.3 Pre-gelatinization and maturation: place the coated meat product in a hot air drying device, set the temperature to 90°C and the humidity to 75%, and treat it with hot air for 12 minutes to pre-gelatinize and mature the coating.

[0289] Freezing: after maturation, naturally cool to room temperature, package with food-grade polyethylene film, and store in a -18°C freezer.

[0290] II. Performance testing

[0291] 1. Sensory quality (color and flavor) testing of meat products

[0292] Sensory evaluation of Example 8 and Example 1. The results show that the total sensory score and each dimension score of Example 8 are significantly higher than those of Example 1. This indicates that the coating step can effectively improve the sensory quality of meat products - the Maillard reaction between pea protein hydrolysate and D-ribose in the coating solution occurs during hot-air cooking and reheating, forming a uniform and attractive brown color, and producing a rich Maillard flavor and rich flavor layers; Example 1 has no coating, and after reheating, it only presents the color and flavor of meat itself, without brown color and obvious Maillard flavor, and the sensory performance is poor, verifying the improvement of the coating step on the sensory quality.

[0293] 2. Detection of juice rate of meat products

[0294] Detection method: Determine the mass of meat products before and after reheating (10 minutes in 85°C water bath) after 3 months of frozen storage, and the juice rate = (mass after reheating / mass before reheating) x 100%, each sample is repeated 3 times to take the average value.

[0295] Detection sample: meat products after 3 months of frozen storage in Example 8 and Example 1. The detection results are shown in Table 12:

[0296] Table 12 Detection results

[0297]

[0298] The juice rate of Example 8 is higher than that of Example 1. This is because the gel network formed by sodium alginate and potato starch in the coating can act as a barrier layer to reduce internal juice evaporation loss during reheating; Example 1 has no such barrier layer, and the juice is easily volatilized through the surface during reheating, resulting in a lower juice rate, which proves that the coating step can effectively improve the water retention of meat products and reduce the loss of juice during reheating.

[0299] 3. Detection of total number of surface microorganisms of meat products after frozen storage

[0300] Detection method: Sample the surface of meat products after 3 months of frozen storage, and determine the total number of colonies (CFU / g) to evaluate the inhibitory effect of coating on microbial growth.

[0301] Detection sample: meat products after 3 months of frozen storage in Example 8 and Example 1. The detection results are shown in Table 13:

[0302] Table 13 Detection results

[0303]

[0304] The total number of surface colonies in Example 8 was lower than that in Example 1. This is because the gel layer formed by the coating can create a physical barrier on the surface of meat products, reducing the attachment and invasion of external microorganisms. At the same time, the synergistic effect of pea protein hydrolysate and sodium alginate can inhibit microbial growth to a certain extent. In Example 1, due to the lack of coating protection, microorganisms easily adhered to the surface without any inhibitory effect, resulting in a higher total number of colonies. This further demonstrates the auxiliary effect of the coating step in improving the storage safety of meat products.

[0305] In another technical solution, the cooking process in step S3 adopts a programmed heating mode, specifically including:

[0306] S8.1 Place the chopped minced meat in a water bath with an initial temperature of 50℃ and keep it for 10-15 minutes;

[0307] S8.2. Increase the water temperature from 50℃ to 72℃ at a heating rate of 0.8-1.2℃ per minute;

[0308] S8.3, Keep at 72℃ for 5-10 minutes;

[0309] S8.4 Transfer the product to hot water at 85°C and cook for 5 minutes to complete the final setting.

[0310] In the above technical solution, during meat processing, the chopped minced meat is poured into a stainless steel mold and gently pressed into shape, followed by a programmed heating and cooking process. The first step involves placing the molded minced meat in a water bath with an initial temperature of 50°C for 10-15 minutes. The second step involves uniformly increasing the water bath temperature from 50°C to 72°C at a rate of 0.8-1.2°C per minute. The third step involves maintaining the water temperature at 72°C for 8 minutes. The fourth step involves removing the treated minced meat mold from the water bath and quickly transferring it to hot water at 85°C for 5 minutes to complete the final shaping and sterilization.

[0311] After cooking, the meat products are removed from the molds, allowed to cool naturally to room temperature, packaged in food-grade polyethylene film, and frozen in a -18°C freezer. The water bath equipment and temperature control devices used in the entire programmed heating and cooking process are all commercially available standard food processing equipment.

[0312] Through the programmed heating process, the protein molecules in the meat paste can be sequentially and gently denatured and cross-linked, avoiding the disordered aggregation of proteins caused by instantaneous high temperature, thereby guiding the formation of a more fine and uniform three-dimensional gel network structure. This structure not only can balance the elasticity and tenderness of the meat product to a certain extent, reduce the problem of too hard or too soft taste, but also can improve the overall water holding capacity of the meat product, reduce the loss of juice during cooking, and help the uniform distribution of functional factors such as lycopene in the meat product, maintain its stability. Compared with the traditional direct high-temperature cooking, the process can more accurately control the timing of heat energy input, so that the cooking effect of each batch of meat products is more stable, and the quality difference caused by the fluctuation of cooking conditions is reduced.

[0313] Although embodiments of the present application have been disclosed as above, they are not limited only to the use listed in the specification and embodiments, and can be fully applied to various fields suitable for the present application, and additional modifications can be easily made by those skilled in the art, and therefore the present application is not limited to specific details and examples shown and described herein, without departing from the general concept defined by the claims and the equivalent scope.

Claims

1. A method for multi-dimensional regulation of meat product quality based on lycopene complex emulsion, characterized in that, The method comprises the following steps: S1, preparing a basic meat paste: grinding fresh meat, adding 2.0% of salt, 0.2%-0.3% of sodium tripolyphosphate and 20% of ice water by weight of the meat at 4-8℃, and chopping and stirring to form a basic meat paste; S2, constructing a heat-induced protein-polysaccharide complex emulsification system, specifically comprising the following steps: S2.1, taking a 4%-8% soybean protein isolate aqueous solution, heating in a water bath at 85-95℃ for 20-40 minutes, and then cooling to 40-60℃ to obtain a protein solution; S2.2, adding molten lycopene-pig oil and food-grade inulin to the protein solution, mixing to obtain a pretreatment liquid; wherein the mass ratio of the molten lycopene-pig oil to the protein solution is 1:1-3, the addition amount of the molten lycopene-pig oil accounts for 5%-10% of the total mass of the basic meat paste, the addition amount of the lycopene accounts for 0.002%-0.015% of the total mass of the basic meat paste, and the addition amount of the inulin accounts for 2%-5% of the mass of the molten lycopene-pig oil; S2.3, homogenizing the pretreatment liquid at 50-80MPa for 2-4 times, and then homogenizing at 100-150MPa for 1-3 times to obtain a lycopene-loaded emulsion; S2.4, adding the lycopene-loaded emulsion to the basic meat paste of S1, chopping and stirring at a low frequency of 1500-2500rpm for 2-4 minutes, and then chopping and stirring at a high frequency of 3500-4500rpm for 3-6 minutes to obtain chopped meat paste; S3, shaping and post-processing: cooking the chopped meat paste in hot water at 80-85℃ to shape, obtaining a meat product, and then cooling, packaging and freezing at-18℃ or below.

2. The method for multi-dimensional quality regulation of meat products based on lycopene complex emulsion according to claim 1, characterized in that, In the step S2.3, after homogenizing at 100-150MPa for 1-3 times, a homogenate is obtained, and the following operations are performed on the homogenate to obtain the lycopene-loaded emulsion: adding 0.05%-0.2% of rosemary extract and 0.1%-0.3% of β-sitosterol to the homogenate, stirring at 40-50℃ and 3000-5000rpm for 15-30 minutes, and then cooling to 4℃ within 5 minutes and standing for 12-24 hours to obtain the lycopene-loaded emulsion.

3. The method for multi-dimensional quality regulation of meat products based on lycopene complex emulsion according to claim 1, characterized in that, After the cooking and shaping in step S3, a quality maintenance agent soaking step S3.1 is further included, specifically as follows: immersing the cooked and shaped meat product in a quality maintenance agent solution at 4-8℃ for 30-60 minutes, taking it out, then draining, and then packaging and freezing; the quality maintenance agent solution is an aqueous solution containing 1%-3% trehalose and 0.5%-1.5% konjac glucomannan.

4. The method for multi-dimensional quality regulation of meat products based on lycopene complex emulsion according to claim 2, characterized in that, After the standing maturation of S2.3 step for 12-24 hours, a standing liquid is obtained, and the standing liquid is subjected to the following operation to obtain the lycopene-loaded emulsion: the standing liquid is incubated with an equal volume of papain solution at 37℃ and pH 7.0 under oscillation at 100-150 rpm for 20-40 minutes, followed by heating at 85℃ for 5 minutes to inactivate the enzyme, and cooling to below 4℃ within 5 minutes to obtain the lycopene-loaded emulsion; wherein the enzyme activity of the papain solution is 500-2000 U / mL.

5. The method for multi-dimensional quality regulation of meat products based on lycopene complex emulsion according to claim 1, characterized in that, The S1 step specifically comprises: S1.1, pre-hydration: mixing the composite flavor carrier with a portion of ice water accounting for 20%-40% of the total amount of ice water, and stirring until completely dissolved and dispersed to form a flavor carrier solution; the composite flavor carrier comprises: 0.5%-1% of yeast extract, 0.2%-0.5% of mushroom powder, and 0.5%-1% of modified citrus fiber, and the balance is a food-grade carrier; S1.2, chopping and blending extraction: chopping fresh meat, and mixing with 2.0% of salt by weight of the meat, 0.2%-0.3% of sodium tripolyphosphate by weight of the meat, the flavor carrier solution, and the remaining ice water under the condition of 4-8℃ to form the basic meat paste; wherein the total amount of the composite flavor carrier accounts for 3%-6% of the total mass of the basic meat paste; the modified citrus fiber is prepared by high-pressure homogenization treatment of citrus fiber to dissociate the fiber bundles.

6. The method for multi-dimensional quality regulation of meat products based on lycopene complex emulsion according to claim 2, characterized in that, The chopping and blending in the S2.4 step is carried out in a chopping and blending system with online viscosity feedback control, and the chopping and blending process specifically comprises: S6.1, monitoring the apparent viscosity of the meat paste in real time in the low-frequency chopping and blending stage; S6.2, when the apparent viscosity reaches a first preset threshold η1, the system automatically switches to the high-frequency chopping and blending stage; S6.3, in the high-frequency chopping and blending stage, the apparent viscosity of the meat paste is continuously monitored, and when the rising rate thereof is lower than a second preset threshold Δη / Δt, the system determines that the conformation editing is completed, and automatically stops chopping and blending.

7. The method for multi-dimensional quality modulation of meat products based on lycopene complex emulsion according to claim 1, characterized in that, After the cooling in the S3 step, a Maillard reaction substrate and a heat-induced gel coating step are further included, which specifically comprises: S7.1, preparing a coating liquid: the coating liquid comprises 3%-6% of pea protein hydrolysate, 1%-2% of D-ribose, 0.5%-1.5% of sodium alginate, and 1%-3% of potato starch by mass concentration, and the balance is water; S7.2, immersing the cooked and shaped and cooled meat paste in the coating liquid, and taking it out after 5-15 seconds to form a uniform thin layer; S7.3, placing the coated meat paste in an environment of 85-95℃ and humidity of 70%-80%, and subjecting it to hot air treatment for 8-15 minutes to make the coating pre-gelatinize and mature, and then freezing and storing.

8. The method for multi-dimensional quality modulation of meat products based on lycopene complex emulsion according to claim 1, characterized in that, The cooking process in the S3 step adopts a programmed temperature rising mode, which specifically comprises: S8.1, placing the chopped and blended meat paste in a water bath with an initial temperature of 50℃, and keeping it for 10-15 minutes; S8.2, raising the water temperature from 50℃ to 72℃ at a temperature rising rate of 0.8-1.2℃ per minute; S8.3, keeping it at 72℃ for 5-10 minutes; S8.

4. Transfer the product to hot water at 85°C and cook for 5 minutes to complete the final setting.

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