Preparation method of low-sodium emulsified minced pork based on pH shift modified degreased peanut powder

Abstract

The invention discloses a preparation method of low-sodium emulsified minced pork based on pH shift modified defatted peanut powder, which comprises the following steps: modifying the defatted peanut powder, adjusting the pH value back to 7 to obtain a modified defatted peanut powder dispersion liquid, dissolving sodium chloride, D-sodium erythorbate and sodium nitrite in the modified defatted peanut powder dispersion liquid, uniformly stirring, adding the modified defatted peanut powder dispersion liquid, and uniformly stirring to obtain the low-sodium emulsified minced pork based on pH shift modified defatted peanut powder. Uniformly stirring and cooling to obtain a mixed solution; putting the crushed tenderloin, the crushed pig backfat and the mixed solution into a chopper mixer for chopping to obtain minced pork; removing bubbles and then heating; and cooling to obtain the low-sodium emulsified minced pork. The use amount of sodium chloride in the minced pork processing process is reduced through the degreased peanut powder which is used as an ingredient in the preparation process of the minced pork by pH shift treatment, and the quality of the minced pork is reduced without reducing the sodium without reducing the emulsion. The pH migration treatment is relatively simple, complex equipment and high cost are not needed, the method has the advantage of cost effectiveness, and the cost can be reduced while the product quality is ensured.

Description

Technical Field

[0001] This invention relates to the field of food processing technology, specifically to a method for preparing low-sodium emulsified minced pork based on pH-shifted modified defatted peanut powder. Background Technology

[0002] NaCl is an important food ingredient in the production of emulsified minced meat products, imparting excellent texture, water retention, and flavor to these products. However, excessive sodium intake can have adverse effects on human health. Studies have shown that a high-sodium diet is a significant contributing factor to diseases such as hypertension and stroke. With increasing health awareness, the development of low-sodium emulsified minced pork products has become an important research direction in the meat products industry. However, reducing the addition of salt can lead to a decline in the product's texture, water retention, and other qualities, affecting product quality. Therefore, finding safe and effective substitutes for phosphates and salt has become a research hotspot.

[0003] Defatted peanut powder (DPP) is a byproduct of peanut oil extraction. It is widely available, inexpensive, rich in high-quality plant protein (peanut protein) and dietary fiber, and possesses certain emulsifying properties, making it a high-quality food ingredient. However, the functional properties of natural DPP are limited, hindering its wider application in food systems. pH shifting is an effective protein modification method. By altering the pH of the protein solution, moving it away from its isoelectric point, it induces conformational changes, thereby improving its functional properties. Although a patent has reported the preparation of phosphorus-free emulsified pork mince using defatted peanut powder (CN202411608209.6), further reducing the amount of NaCl added during the pork mince preparation process will inevitably lead to a decrease in texture and water- and oil-retention properties. While existing literature indicates that increasing the amount of defatted peanut powder can reduce salt content without compromising texture in pork mince, excessive addition of peanut powder will further increase product costs and may also cause quality deterioration in the emulsified pork mince due to excessive peanut powder content. To date, no studies have been conducted on further reducing the amount of salt added to emulsified pork grounds by modifying the ingredients used in emulsified pork grounds without improving the texture and water retention properties of the reduced-salt grounds. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of the prior art and provide a low-sodium emulsified pork mince based on pH-shifted modified defatted peanut powder and its preparation. The preparation method of this invention reduces the amount of sodium chloride used in the processing of emulsified pork mince by pH-shifting the defatted peanut powder, while maintaining good texture and water and oil retention properties of the emulsified pork mince.

[0005] To achieve the above objectives, the technical solution designed by the present invention is as follows: This invention provides a method for preparing low-sodium emulsified pork mince based on pH-shifted defatted peanut powder, comprising the following steps: 1) Disperse 7-8 parts of defatted peanut powder in 25.44-26.19 parts of deionized water, stir evenly at room temperature, adjust the pH value to 2 or 12 with an acid-base adjuster, and carry out acid modification or alkaline modification under stirring conditions at room temperature; to obtain a solution of modified defatted peanut powder; 2) Use an acid-base adjuster to adjust the pH value of the modified defatted peanut powder solution back to 7, obtain a modified defatted peanut powder dispersion containing sodium chloride, and measure and calculate the amount of sodium chloride produced in this process. 3) Dissolve sodium chloride, 0.5 parts of sodium D-isoascorbate and 0.1 parts of sodium nitrite in the above modified defatted peanut powder dispersion containing sodium chloride, stir evenly, and cool to obtain a mixed solution; wherein, when adding sodium chloride, the sodium chloride content in the modified defatted peanut powder dispersion is included in the total sodium chloride content; 4) Remove the connective tissue from the tenderloin, and use a meat grinder to grind the tenderloin and pork back fat separately; to obtain ground tenderloin and ground pork back fat. 5) Place 55 parts minced pork tenderloin and 10 parts minced pork back fat into the mixture obtained in step 3) and mince it multiple times in a chopper to obtain pork mince. 6) After removing air bubbles from the prepared pork mince, heat it; after heating, cool it to obtain low-sodium emulsified pork mince for later use. The total sodium chloride content in each 100g of low-sodium emulsified pork mince is ≤0.75g.

[0006] Further, in step 1), the acid-base adjuster is 1M HCl or 1M NaOH.

[0007] Furthermore, in step 3), the cooling temperature is 4°C and the time is 1 hour.

[0008] Furthermore, in step 5), the chopper rotates at 3000 rpm, chopping for 1 minute each time with a 1-minute interval, and the temperature of the minced meat does not exceed 12°C during the chopping process.

[0009] Furthermore, in step 6), the heating temperature is 80°C and the heating time is 1 hour.

[0010] The beneficial effects of this invention are: 1. This invention reduces the amount of sodium chloride used in the minced pork processing by adjusting the pH of defatted peanut powder used in the minced pork preparation process, thereby reducing sodium without compromising the quality of the emulsified minced pork.

[0011] 2. The pH shifting process of the present invention is relatively simple, does not require complex equipment or high costs, and has certain cost-effectiveness advantages, reducing costs while ensuring product quality. Attached Figure Description

[0012] Figure 1 A schematic diagram showing the hardness of different groups of emulsified minced pork; Figure 2 A schematic diagram illustrating the elasticity of different groups of emulsified minced pork; Figure 3 A schematic diagram illustrating the cohesiveness of different groups of emulsified minced pork; Figure 4 A schematic diagram illustrating the adhesive properties of different groups of emulsified minced pork; Figure 5 A schematic diagram illustrating the chewiness of different groups of emulsified minced pork; Figure 6 A schematic diagram illustrating the resilience of different groups of emulsified minced pork; Figure 7 A schematic diagram showing the cooking loss of different groups of emulsified minced pork; Figure 8 A schematic diagram showing the total liquid release of different groups of emulsified minced pork; Figure 9 A schematic diagram showing the water release rates of different groups of emulsified minced pork. Figure 10 A schematic diagram showing the fat release of different groups of emulsified minced pork. Detailed Implementation

[0013] The present invention will now be described in further detail with reference to specific embodiments, so that those skilled in the art can understand it.

[0014] Example 1 A method for preparing low-sodium emulsified pork mince 1 based on pH-shifted modified defatted peanut powder includes the following steps: 1) Disperse 7.75g of defatted peanut powder in 26.44g of deionized water, stir at room temperature for 30min, add 1MHCl to adjust the pH to 2, and carry out acid modification for 1h at room temperature with stirring; to obtain a solution of modified defatted peanut powder; 2) Use 1M NaOH to adjust the pH value of the modified defatted peanut powder solution back to 7, obtain a modified defatted peanut powder dispersion containing sodium chloride, and measure and calculate the amount of sodium chloride produced in this process. 3) Dissolve sodium chloride, 0.05g of sodium D-isoascorbate and 0.01g of sodium nitrite in the above modified defatted peanut powder dispersion containing sodium chloride, stir evenly, and cool to obtain a mixed solution; wherein, when adding sodium chloride, the sodium chloride content in the modified defatted peanut powder dispersion is included in the total sodium chloride content, so that the total sodium chloride content in the mixed solution is 0.75g / 100g, so that the total sodium chloride content in the final minced meat product is 0.75g / 100g; 4) Remove the connective tissue from the tenderloin, and use a meat grinder to grind the tenderloin and pork back fat separately; to obtain ground tenderloin and ground pork back fat. 5) Place 55g of minced pork tenderloin and 10g of minced pork back fat into the mixture obtained in step 3) and chop it multiple times in a chopper at a speed of 3000 rpm for 1 minute each time, with a 1-minute break between each chopping. The temperature of the minced meat should not exceed 12℃ during the chopping process to obtain minced pork. 6) After removing air bubbles, put the prepared minced meat into a specific container and heat it at 80℃ for 1 hour. After heating, cool it to obtain low-sodium emulsified pork minced meat 1 for later use. The total sodium chloride content in 100g of low-sodium emulsified pork minced meat 1 is 0.75g.

[0015] Example 2 A method for preparing low-sodium emulsified pork mince 2 based on pH-shifted modified defatted peanut powder includes the following steps: 1) Disperse 8.0g of defatted peanut powder in 26.19g of deionized water, stir for 30min at room temperature, add 1MHCl to adjust the pH to 2, and carry out acid modification for 1h at room temperature with stirring; to obtain a solution of modified defatted peanut powder; 2) Use 1M NaOH to adjust the pH value of the modified defatted peanut powder solution back to 7, obtain a modified defatted peanut powder dispersion containing sodium chloride, and measure and calculate the amount of sodium chloride produced in this process. 3) Dissolve sodium chloride, 0.05g of D-isoascorbic acid sodium and 0.01g of sodium nitrite in the above modified defatted peanut powder dispersion containing sodium chloride, stir evenly, and cool to obtain a mixed solution; wherein, when adding sodium chloride, the sodium chloride content in the modified defatted peanut powder dispersion is included in the total sodium chloride content, so that the total sodium chloride content in the mixed solution is 0.75g / 100g; 4) Remove the connective tissue from the tenderloin, and use a meat grinder to grind the tenderloin and pork back fat separately; to obtain ground tenderloin and ground pork back fat. 5) Place 55g of minced pork tenderloin and 10g of minced pork back fat into the mixture obtained in step 3) and chop it multiple times in a chopper at a speed of 3000 rpm for 1 minute each time, with a 1-minute break between each chopping. The temperature of the minced meat should not exceed 12℃ during the chopping process to obtain minced pork. 6) After removing air bubbles, put the prepared minced meat into a specific container and heat it at 80℃ for 1 hour. After heating, cool it to obtain low-sodium emulsified pork minced meat 2 for later use. The total sodium chloride content in 100g of low-sodium emulsified pork minced meat 2 is 0.75g.

[0016] Example 3 A method for preparing low-sodium emulsified pork mince 3 based on pH-shift modified defatted peanut powder includes the following steps: 1) Disperse 7.75g of defatted peanut powder in 26.44g of deionized water, stir at room temperature for 30min, add 1M NaOH to adjust the pH to 12, and carry out alkaline modification for 1h at room temperature with stirring; to obtain a solution of modified defatted peanut powder; 2) Use 1M HCl to adjust the pH of the modified defatted peanut powder solution back to 7 to obtain a modified defatted peanut powder dispersion containing sodium chloride, and measure and calculate the amount of sodium chloride produced in this process. 3) Dissolve sodium chloride, 0.05g of D-isoascorbic acid sodium and 0.01g of sodium nitrite in the above modified defatted peanut powder dispersion containing sodium chloride, stir evenly, and cool to obtain a mixed solution; wherein, when adding sodium chloride, the sodium chloride content in the modified defatted peanut powder dispersion is included in the total sodium chloride content, so that the total sodium chloride content in the mixed solution is 0.75g / 100g; 4) Remove the connective tissue from the tenderloin, and use a meat grinder to grind the tenderloin and pork back fat separately; to obtain ground tenderloin and ground pork back fat. 5) Place 55g of minced pork tenderloin and 10g of minced pork back fat into the mixture obtained in step 3) and chop it multiple times in a chopper at a speed of 3000 rpm for 1 minute each time, with a 1-minute break between each chopping. The temperature of the minced meat should not exceed 12℃ during the chopping process to obtain minced pork. 6) After removing air bubbles, put the prepared minced meat into a specific container and heat it at 80℃ for 1 hour. After heating, cool it to obtain low-sodium emulsified pork minced meat 3 for later use. The total sodium chloride content in 100g of low-sodium emulsified pork minced meat 3 is 0.75g.

[0017] Example 4 A method for preparing low-sodium emulsified pork mince 4 based on pH-shifted modified defatted peanut powder includes the following steps: 1) Disperse 8.0g of defatted peanut powder in 26.19g of deionized water, stir at room temperature for 30min, add 1M NaOH to adjust the pH to 12, and carry out alkaline modification at room temperature with stirring for 1h; to obtain a solution of modified defatted peanut powder; 2) Use 1M HCl to adjust the pH of the modified defatted peanut powder solution back to 7 to obtain a modified defatted peanut powder dispersion containing sodium chloride, and measure and calculate the amount of sodium chloride produced in this process. 3) Dissolve sodium chloride, 0.05g of D-isoascorbic acid sodium and 0.01g of sodium nitrite in the above modified defatted peanut powder dispersion containing sodium chloride, stir evenly, and cool to obtain a mixed solution; wherein, when adding sodium chloride, the sodium chloride content in the modified defatted peanut powder dispersion is included in the total sodium chloride content, so that the total sodium chloride content in the mixed solution is 0.75g / 100g; 4) Remove the connective tissue from the tenderloin, and use a meat grinder to grind the tenderloin and pork back fat separately; to obtain ground tenderloin and ground pork back fat. 5) Place 55g of minced pork tenderloin and 10g of minced pork back fat into the mixture obtained in step 3) and chop it multiple times in a chopper at a speed of 3000 rpm for 1 minute each time, with a 1-minute break between each chopping. The temperature of the minced meat should not exceed 12℃ during the chopping process to obtain minced pork. 6) After removing air bubbles, put the prepared minced meat into a specific container and heat it at 80℃ for 1 hour. After heating, cool it to obtain low-sodium emulsified pork minced meat 4 for later use. The total sodium chloride content in 100g of low-sodium emulsified pork minced meat 4 is 0.75g.

[0018] Comparative Example 1 Step 1: Dissolve 1.5g sodium chloride, 8g defatted peanut powder, 0.05g sodium D-isoascorbate and 0.01g sodium nitrite in 25.44g deionized water, stir thoroughly until the defatted peanut powder is fully dispersed and the remaining components are completely dissolved, and then cool to 4℃. Step 2: Remove the connective tissue from the tenderloin and mince the tenderloin and pork back fat using a meat grinder (6nm perforated plate); Step 3: Pour the solution from Step 1, the 55g minced pork tenderloin and 10g pork back fat into a meat chopper. Chop at 3000 rpm for 1 minute each time, with a 1-minute break between chops. The temperature during chopping should not exceed 12℃ to make minced pork. Step 4: After removing air bubbles, place the prepared minced meat into a specific container and heat at 80°C for 1 hour; Step 5: After heating, cool to obtain emulsified minced pork 1, set aside.

[0019] Comparative Example 2 Step 1: Dissolve 0.75g sodium chloride, 8g defatted peanut powder, 0.05g sodium D-isoascorbate and 0.01g sodium nitrite in 26.19g deionized water, stir thoroughly until defatted peanut powder is fully dispersed and the remaining components are completely dissolved, and then cool to 4℃. Step 2: Remove the connective tissue from the tenderloin and mince the tenderloin and pork back fat using a meat grinder; Step 3: Pour the fully dispersed and dissolved solution from Step 1, 55g of minced pork tenderloin and 10g of pork back fat into a meat chopper. Chop at 3000rpm for 1 minute each time, with a 1-minute break between chops. The temperature during the chopping process should not exceed 12℃ to make minced pork. Step 4: After removing air bubbles, place the prepared minced meat into a specific container and heat at 80°C for 1 hour; Step 5: After heating, cool to obtain emulsified minced pork 2, set aside.

[0020] The hardness, elasticity, cohesiveness, chewiness, adhesiveness, and resilience of low-sodium emulsified pork mince 1-4 and emulsified pork mince 1-2 were measured. Equipment name and model used: Equipment Name 1: Magnetic Stirrer, Model: 84-1 Equipment Name 2: Meat Grinder, Model: SZ-22A Equipment Name 3: Chopper, Model: GM200 Equipment Name 4: High-speed refrigerated centrifuge, Model: TGL-20kR Equipment Name 5: Digital Display Thermostatic Water Bath, Model: HH-8 The low-sodium emulsified pork mince 1-4 and emulsified pork mince 1-2 obtained from Examples 1-4 and Comparative Examples 1-2 were cut into cylinders with a diameter of approximately 25 mm and a height of approximately 15 mm, respectively. The TPA was measured using a food physical property analyzer, and the test program was set as follows: Using a P / 36R probe with a strain of 50% and a trigger force of 5g, the hardness, elasticity, cohesiveness, chewiness, adhesiveness, and resilience of emulsified minced pork with different ratios were measured.

[0021] Determination of cooking loss: 30g of minced meat was placed in a 50mL centrifuge tube and centrifuged at 500g for 5 minutes at 4℃. The tube was then heated in an 80℃ water bath for 1 hour, immediately followed by cooling in an ice water bath for 10 minutes. After cooling to room temperature, surface moisture was wiped off. The formula for calculating cooking loss is: ×100 The emulsified minced pork was weighed (M0) and heated at 80°C for 30 minutes. It was then centrifuged at 3000g for 5 minutes, and the supernatant was weighed and recorded as M1. The supernatant was dried at 105°C until constant weight and weighed to determine the amount of fat released, recorded as M2. The total liquid release, water release, and fat release were calculated using the following formulas.

[0022] ×100 ×100 ×100 like Figures 1-10 As shown, the control group (emulsified pork mince 2 prepared in Comparative Example 2) with added original defatted peanut powder and 0.75% NaCl had worse texture and water retention than the control group (emulsified pork mince 1 prepared in Comparative Example 1) with added original defatted peanut powder and 1.5% NaCl. The texture properties of the mince gel were significantly improved after adding pH 2 or pH 12-shifted modified defatted peanut powder to the mince. With a 50% reduction in NaCl content, by adding an equal amount of pH 2 or pH 12-shifted modified defatted peanut powder, the hardness, elasticity, cohesiveness, adhesiveness, chewiness, and resilience of low-sodium emulsified pork mince 1-4 (Examples 1, 2, 3, and 4) were comparable to the control group (Comparative Example 1) which contained the original defatted peanut powder and 1.5% NaCl. This indicates that the pH-shifted defatted peanut powder can cross-link more tightly with pork protein, forming a robust network structure that ensures good taste and quality even under low-sodium conditions. The pH 2 or pH 12-shifted defatted peanut powder and pork protein can form a strong and compact gel network structure, effectively binding water within the protein network and improving the water-holding capacity of the mince. This not only reduces sodium addition but also produces emulsified mince products with excellent texture, meeting consumers' demands for health and quality.

[0023] The ability of emulsified pork mince to bind water and fat after adding pH-shifted modified defatted peanut powder was evaluated by measuring cooking loss and emulsification stability. Compared with the control group (Comparative Example 1) which added original defatted peanut powder and 1.5% NaCl, the control group (Comparative Example 2) which added original defatted peanut powder and 0.75% NaCl had higher cooking loss, total liquid release, water release, and fat release, at 10.10%, 5.86%, 5.43%, and 0.43%, respectively, indicating that the emulsified pork mince still had poor water and oil retention properties under low-sodium conditions. When modified defatted peanut powder with pH 2 or pH 12 shift was added, the cooking loss, total liquid release, water release, and fat release of low-sodium emulsified pork mince 1-4 (Examples 1, 2, 3, and 4) were significantly reduced. This indicates that defatted peanut flour modified with pH 2 or pH 12 offsets has better emulsifying ability, can more effectively encapsulate oil droplets, form a stable emulsion system, and can better retain juice during processing and storage, making the product juicier.

[0024] All other parts not described in detail are existing technologies. Although the above embodiments have provided a detailed description of the present invention, they are only some embodiments of the present invention, not all embodiments. People can obtain other embodiments based on these embodiments without creative effort, and these embodiments all fall within the protection scope of the present invention.

Claims

1. A method for preparing low-sodium emulsified pork mince based on pH-shift modified defatted peanut powder, characterized in that: Includes the following steps: 1) Disperse 7-8 parts of defatted peanut powder in 25.44-26.19 parts of deionized water, stir evenly at room temperature, adjust the pH value to 2 or 12 with an acid-base adjuster, and carry out acid modification or alkaline modification under stirring conditions at room temperature; A solution of modified defatted peanut powder was obtained; 2) Use an acid-base adjuster to adjust the pH value of the modified defatted peanut powder solution back to 7, obtain a modified defatted peanut powder dispersion containing sodium chloride, and measure and calculate the amount of sodium chloride produced in this process. 3) Dissolve sodium chloride, 0.5 parts of sodium D-isoascorbate and 0.1 parts of sodium nitrite in the above modified defatted peanut powder dispersion containing sodium chloride, stir evenly, and cool to obtain a mixed solution; wherein, when adding sodium chloride, the sodium chloride content in the modified defatted peanut powder dispersion is included in the total sodium chloride content; 4) Remove the connective tissue from the tenderloin, and use a meat grinder to grind the tenderloin and pork back fat separately; to obtain ground tenderloin and ground pork back fat. 5) Place 55 parts minced pork tenderloin and 10 parts minced pork back fat into the mixture obtained in step 3) and mince it multiple times in a chopper to obtain pork mince. 6) After removing air bubbles from the prepared pork mince, heat it; after heating, cool it to obtain low-sodium emulsified pork mince for later use. The total sodium chloride content in each 100g of low-sodium emulsified pork mince is ≤0.75g.

2. The preparation method according to claim 1, characterized in that: In step 1), the acid-base regulator is 1M HCl or 1M NaOH.

3. The method for preparing the low concentration according to claim 1, characterized in that: In step 3), the cooling temperature is 4 ℃ and the time is 1 hour.

4. The preparation method according to claim 1, characterized in that: In step 5), the chopper rotates at 3000 rpm, chopping for 1 minute each time, with a 1-minute break between each chopping, and the temperature of the minced meat does not exceed 12 ℃ during the chopping process.

5. The preparation method according to claim 1, characterized in that: In step 6), the heating temperature is 80 ℃ and the heating time is 1 h.

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