A high-gel type egg white product, its preparation method and application

Abstract

This invention belongs to the field of food processing technology, specifically relating to a high-gel egg white product, its preparation method, and its application. The method includes the following steps: mixing plant protein, animal collagen, and egg white liquid to obtain a mixture; enzymatically hydrolyzing the mixture with glucose oxidase to obtain an enzymatic hydrolysate; and microwaving the enzymatic hydrolysate under vacuum at low temperature to obtain the high-gel egg white product. The preparation method of the high-gel egg white product of this invention utilizes plant protein to stabilize the structure of the high-gel egg white powder, and adds animal collagen to enrich the functionality of the high-gel egg white powder. Simultaneously, the enzymatic hydrolysis of the mixture with glucose oxidase avoids the off-flavors produced by yeast desaccharification. Furthermore, the microwaving under vacuum at low temperature allows for protein dechaining during microwave modification of the raw materials, followed by cross-linking reactions, which significantly improves the gelling properties of the egg white product. This also significantly shortens the production cycle, reduces energy consumption, and improves efficiency.

Description

Technical Field

[0001] This invention belongs to the field of food processing technology, specifically relating to a high-gel type egg white product, its preparation method, and its application. Background Technology

[0002] Egg white powder is a dry powder product made from egg white liquid through spray drying. As a substitute for fresh eggs, it is widely used in various fields such as food, textiles, leather, papermaking, and medicine. In particular, its unique gelling properties can improve product texture, and it has gained high recognition in various food processing applications.

[0003] High-gelling egg white powder, as a substitute for liquid egg white, is easy to store and transport. However, while ordinary egg white powder has relatively high gelling properties, it still cannot meet the processing requirements of certain industries in practical applications. Current technologies improve the gelling properties of egg white powder by adding thickeners such as xanthan gum; however, the extensive use of chemical thickeners undoubtedly poses safety risks. Therefore, there is an urgent need to provide a safer egg white product with superior gelling performance. Summary of the Invention

[0004] To address the shortcomings of existing technologies, the present invention aims to provide a high-gelling egg white product, its preparation method, and its applications. The preparation method of the high-gelling egg white product provided by the present invention has a short production cycle, does not require the addition of any thickeners, and results in an egg white product with stronger gelation and better flavor.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] This invention provides a method for preparing a high-gel egg white product, comprising the following steps: mixing plant protein, animal collagen and egg white liquid to obtain a mixture; hydrolyzing the mixture with glucose oxidase to obtain an enzymatic hydrolysate; and drying the enzymatic hydrolysate under microwave vacuum at low temperature to obtain a high-gel egg white product.

[0007] Preferably, the glucose oxidase added accounts for 0.01% to 0.05% of the total mass of the mixture.

[0008] Preferably, the enzymatic hydrolysis is performed at a temperature of 35–45°C for 3–8 hours.

[0009] Preferably, the pH of the mixture is adjusted to 6.0-7.0 before the enzymatic hydrolysis.

[0010] Preferably, the enzymatic hydrolysis is followed by enzyme inactivation, wherein the enzyme inactivation temperature is 35–55°C and the time is 20–40 min.

[0011] Preferably, the microwave power of the microwave vacuum low-temperature drying is 450-550W, the vacuum degree is 1000-2000Pa, the temperature is 15-30℃, and the time is 1-5h.

[0012] Preferably, the mass ratio of the plant protein, animal collagen, and egg white liquid is 10-20:1-10:70-100.

[0013] This invention provides a highly gel-type egg white product prepared using the above-described preparation method.

[0014] The present invention also provides the application of the above-mentioned high-gel type egg white product in the preparation of minced meat.

[0015] Preferably, the mass of the high-gel-type egg white product accounts for 0.1% to 5% of the total mass of the minced meat.

[0016] Beneficial Effects: This invention provides a method for preparing high-gel egg white products. Plant protein, animal collagen, and egg white liquid are mixed. The addition of plant protein stabilizes the structure of the high-gel egg white powder, while the addition of animal collagen enriches its functionality, resulting in egg white products with higher cost-effectiveness and functionality. Simultaneously, the protein structure in food not only provides structural support but also enhances the product's texture. This invention also utilizes glucose oxidase to hydrolyze the mixture, avoiding the off-flavors produced by yeast desaccharification, effectively improving the texture of the egg white products and making them more palatable. Furthermore, this invention utilizes microwave vacuum low-temperature drying. During microwave modification, the proteins in each raw material undergo dechaining, followed by a cross-linking reaction. This effectively forms a better cross-linked structure, significantly improving the gelling properties of the egg white products. Simultaneously, it significantly shortens the production cycle, reduces energy consumption, and increases efficiency.

[0017] This invention provides a highly gelling egg white product prepared by the above-described method. It is a white or pale yellow powder, odorless and tasteless, free of impurities, has good solubility and is easily absorbed. It also possesses good functionality and gelling properties, with a gel strength reaching 1200–1300 g / cm³. 2 .

[0018] This invention also provides the application of the above-mentioned high-gelling egg white product in the preparation of minced meat. Adding high-gelling egg white powder to minced meat can effectively improve the gelling properties and texture of minced meat. The gel strength of the product is increased by 5% to 8% after adding this product compared with adding egg white liquid. Attached Figure Description

[0019] Figure 1 This is a structural diagram of a microwave belt vacuum liquid cryogenic dryer;

[0020] Figure 2This is a process flow diagram for using high-gel egg white products to prepare minced meat. Detailed Implementation

[0021] This invention provides a method for preparing a high-gel egg white product, comprising the following steps: mixing plant protein, animal collagen and egg white liquid to obtain a mixture; hydrolyzing the mixture with glucose oxidase to obtain an enzymatic hydrolysate; and drying the enzymatic hydrolysate under microwave vacuum at low temperature to obtain a high-gel egg white product.

[0022] Unless otherwise specified, the present invention does not have special requirements for the raw materials used in the preparation, and commercially available products well known to those skilled in the art can be used.

[0023] This invention preferably involves mixing plant protein, animal collagen, and egg white liquid to obtain a mixture. The plant protein used in this invention is preferably hydrolyzed rice protein. Using hydrolyzed rice protein not only improves the structural stability of the food but also enhances the gelling properties of egg white products. This invention utilizes the three procollagen peptide chains of animal collagen, which intertwine with each other through interchain hydrogen bonds to form a stable three-dimensional helical structure, effectively improving the strength of collagen and further enhancing product stability. The animal collagen used in this invention is preferably fish collagen, which not only makes full use of my country's aquatic resources but also reduces the environmental pollution caused by aquatic processing byproducts. This invention preferably uses hydrolyzed rice protein and fish collagen, both of which have more stable and economical prices and wider availability, reducing costs and improving product efficiency during the production process.

[0024] The preferred mass ratio of plant protein, animal collagen, and egg white liquid in this invention is 10-20:1-10:70-100, more preferably 12-18:3-8:74-95, even more preferably 13-16:4-7:80-90, and most preferably 15:5:85. This invention does not specifically limit the egg white liquid, but fresh egg white liquid is preferred. The plant protein and animal collagen in this invention are preferably light-colored, low-turbidity, and odorless proteins; the light color is more preferably close to the color of egg white.

[0025] The present invention preferably further includes adjusting the pH of the mixture to 6.0-7.0 before enzymatic hydrolysis, more preferably 6.2-6.8, more preferably 6.4-6.6, and most preferably 6.5. In the embodiments of the present invention, 0.1 mol / L food-grade citric acid is used for adjustment. A slightly acidic or alkaline pH affects protein stability and is not conducive to the subsequent microwave drying process; the reaction effect is best within the optimal pH range.

[0026] In this invention, the above-mentioned mixture is preferably hydrolyzed with glucose oxidase to obtain an enzymatic hydrolysate. Using glucose oxidase for hydrolysis not only completes the desugaring process but also avoids the off-flavors produced by adding yeast for desugaring. The glucose oxidase added in this invention is preferably 0.001% to 0.05% of the total mass of the mixture, more preferably 0.005% to 0.03%, more preferably 0.008% to 0.02%, and most preferably 0.01%.

[0027] The preferred enzymatic hydrolysis temperature of this invention is 35–45°C, more preferably 37–42°C, even more preferably 39–41°C, and most preferably 40°C; lower temperatures result in lower hydrolysis efficiency, while higher temperatures easily denature proteins, leading to the formation of flocculent substances. The preferred enzymatic hydrolysis time of this invention is 3–8 hours, more preferably 3.5–7 hours, even more preferably 4–6 hours, and most preferably 5 hours; shorter times result in insufficient hydrolysis efficiency, while longer times waste resources.

[0028] In this invention, the enzyme hydrolysate after the above-mentioned enzymatic hydrolysis is preferably inactivated. The enzyme inactivation temperature is preferably 35–55°C, more preferably 40–50°C, even more preferably 43–47°C, and most preferably 45°C; low-temperature sterilization can reduce the impact on protein structure. The enzyme inactivation time is preferably 20–40 min, more preferably 25–35 min, even more preferably 28–32 min, and most preferably 30 min.

[0029] The present invention preferably concentrates the enzyme hydrolysate after enzyme inactivation. This concentration is preferably performed using a microwave tube concentrator, which removes some water, facilitating subsequent microwave vacuum low-temperature drying. The water content of the concentrated enzyme hydrolysate is preferably 30%–50%, more preferably 35%–45%, and even more preferably 40%.

[0030] This invention preferably involves microwave vacuum low-temperature drying of the concentrated enzymatic hydrolysate to obtain a high-gel egg white product. The microwave power for microwave vacuum low-temperature drying is preferably 450–550 W, more preferably 480–530 W, more preferably 500–510 W, and most preferably 505 W; the vacuum degree for microwave vacuum low-temperature drying is preferably 1000–2000 Pa, more preferably 1200–1800 Pa, more preferably 1400–1600 Pa, and most preferably 1500 Pa; the temperature for microwave vacuum low-temperature drying is preferably 15–30 °C, more preferably 17–25 °C, more preferably 19–23 °C, and most preferably 20 °C; the drying time for microwave vacuum low-temperature drying is preferably 1–5 h, more preferably 1.5–4 h, more preferably 2–3 h, and most preferably 2 h. This invention utilizes the high-frequency electromagnetic waves of microwave vacuum low-temperature drying to induce high-speed vibrations in polar molecules within egg white liquid. This causes protein molecules to unfold, exposing internal groups and increasing surface hydrophobicity and the number of surface sulfhydryl groups. On one hand, as protein molecules continue to unfold and surface hydrophobicity and the number of sulfhydryl groups continue to increase, some sulfhydryl groups in the protein are converted into SS bonds, leading to protein polymerization. On the other hand, the microwave treatment process causes water migration, affecting the gel strength. The microwave vacuum drying described in this invention can generate a significant thermal effect in a short time, modifying the protein. Simultaneously, the vacuum low-temperature drying technology can maximize the quality of egg white products, meeting the demand for high-quality products while shortening the production cycle, reducing energy consumption, and improving efficiency.

[0031] This invention provides a high-gelling egg white product prepared by the above preparation method. It is a white or light yellow powder, without fishy or odor, free of impurities, with good solubility and easy absorption. It has good functionality and gelling properties, and its gel strength level is basically consistent with that of egg white powder that can be achieved by passing it through a hot chamber.

[0032] This invention also provides the application of the above-mentioned high-gelling egg white product in the preparation of minced meat. The minced meat of this invention preferably includes any one of fish paste, chicken paste, duck paste, pork paste, beef paste, and shrimp paste. The high-gelling egg white product of this invention preferably accounts for 0.1% to 5% of the total mass of the minced meat, more preferably 0.5% to 5%, more preferably 1% to 4%, and most preferably 4%. When applying the above-mentioned high-gelling egg white product to the preparation of minced meat, this invention includes incorporating the high-gelling egg white product into the minced meat and stirring evenly to obtain a high-gelling minced meat, thereby improving the gelling properties and texture of the minced meat.

[0033] To further illustrate the present invention, a high-gel type egg white product, its preparation method, and its application are described in detail below with reference to the accompanying drawings and embodiments. However, these descriptions should not be construed as limiting the scope of protection of the present invention.

[0034] Example 1

[0035] A method for preparing a high-gelling egg white powder, specifically comprising the following steps:

[0036] (1) Mix 15g of hydrolyzed rice protein solution, 5g of fish collagen solution and 80g of egg white solution evenly. Use 0.1mol / L food-grade citric acid to adjust the pH value to 6.5 to obtain a preliminary mixed solution.

[0037] (2) Add glucose oxidase at a mass fraction of 0.01% of the mixture and hydrolyze at 40°C for 4 hours to obtain the hydrolysate;

[0038] (3) The reaction solution after enzymatic hydrolysis was pasteurized at 45°C for 30 min to obtain sterilized enzymatic hydrolysate.

[0039] (4) Microwave vacuum freeze-drying technology is used, employing a microwave belt vacuum low-temperature liquid dryer (see structural diagram). Figure 1 The enzymatically sterilized hydrolysate was placed in a microwave tube concentrator and concentrated until the water content of the hydrolysate was 30%. Then it was put into a microwave belt vacuum low-temperature liquid dryer. The equipment was turned on, the microwave power was 505W, the vacuum degree was 1500Pa, and the temperature was 20℃. The hydrolysate was dried in a microwave vacuum low temperature for 2 hours to obtain high-colloid egg white powder.

[0040] Example 2

[0041] The process was carried out in accordance with Example 1, except that in step (1), the raw materials were mixed and the pH was adjusted to reach 6.0 to obtain a preliminary mixed solution; in step 2 (2), glucose oxidase with a mass fraction of 0.02% of the mixed solution was added and enzymatically hydrolyzed at 42°C for 6 hours to obtain the hydrolysate.

[0042] Example 3

[0043] The process was carried out in accordance with Example 1, except that in step (1), the raw materials were mixed and the pH was adjusted to reach 7.0 to obtain a preliminary mixed solution; in step 2 (2), glucose oxidase with a mass fraction of 0.02% of the mixed solution was added and enzymatically hydrolyzed at 40°C for 5 hours to obtain the hydrolysate.

[0044] Comparative Example 1

[0045] The procedure was carried out in accordance with Example 1, except that the enzymatic hydrolysis conditions were replaced with 55°C.

[0046] Comparative Example 2

[0047] The procedure was carried out as described in Example 1, except that the amount of fish collagen solution added was replaced with 10%.

[0048] Comparative Example 3

[0049] The procedure was carried out in accordance with Example 1, except that the amount of hydrolyzed rice protein added was replaced with 30%.

[0050] Experimental Example 1

[0051] Fourier transform infrared spectroscopy (FTIR) was used to analyze the structure of egg white powder. The treated egg white powder sample was mixed with potassium bromide, manually pressed into a pellet, and then scanned using a Fourier transform infrared spectrometer. The resolution was set to 4 cm⁻¹. -1 4000~400cm -1 The wavenumber range was scanned, and the amide I band of the infrared spectrum was deconvolved using Peak Fit v4.12 software, followed by second derivative fitting.

[0052] Differential scanning calorimetry (DSC) was used to analyze the enthalpy. The denaturation temperature of dried egg white protein was determined using DSC. 6–8 mg of egg white powder sample was weighed and compared with Congo, with an empty crucible as a control. Test parameters were set as follows: nitrogen flow rate 20 mL / min, heating rate 10 °C / min, and the temperature range was 20–150 °C to obtain the curve.

[0053] Total thiol determination: Prepare a solution of egg white powder in PBS buffer with a concentration of 2 mg / mL. Take 0.5 mL and add it to 2 mL of buffer (8% SDS, 8M urea, 0.1M PBS, pH 7.4). Add 50 μL of 10 mM Ellman reagent (pH 7.4), mix thoroughly, let stand for 20 min, and then measure the absorbance at 412 nm.

[0054] Surface thiol group determination: 50 μL of Ellman was added to a completely dissolved egg white powder solution (0.5 mg / mL, 2.5 mL), shaken until fully mixed, and allowed to stand for 25 min. The absorbance was then measured at 412 nm.

[0055] The thiol content is calculated using the following formula.

[0056]

[0057] In the formula: D, dilution factor; ρ, final mass concentration of the solution, mg / mL.

[0058] The protein structures of Examples 1-3, egg white liquid, and Comparative Examples 1-3 were determined. Three experiments were conducted, and the average value was calculated. The results are shown in Table 1.

[0059] Table 1. Results of protein structure analysis for different egg white powders

[0060] α-spiral ratio enthalpy value Total sulfhydryl groups of protein Surface thiol groups Example 1 20.29％ 245.70 J / g 52.31％ 3.07％ Example 2 21.74％ 294.65 J / g 50.45％ 2.68％ Example 3 28.04％ 280.40 J / g 47.43％ 2.23％ Egg white liquid 20.62％ 248.35J / g 51.37％ 2.96％ Comparative Example 1 26.34％ 279.42 J / g 46.53％ 2.14％ Comparative Example 2 30.51％ 285.36 J / g 43.47％ 2.03％ Comparative Example 3 33.79％ 297.64 J / g 44.54％ 1.93％

[0061] The tests revealed that Example 1 had the lowest α-helix ratio (20.29%) and the lowest enthalpy (245.70 J / g); however, it had the highest total sulfhydryl and surface sulfhydryl content (52.31% and 3.07%, respectively). Compared to egg white liquid, Example 1 was superior in all aspects; the test results of Examples 2 and 3 were also closer to those of egg white liquid. The comparative examples, however, showed significantly lower performance than egg white liquid. This demonstrates that microwaves can unfold protein molecules, exposing internal groups, increasing surface hydrophobicity and the number of surface sulfhydryl groups, thus modifying the protein and increasing the gelling properties of the product.

[0062] Experimental Example 2

[0063] The gelation properties of Examples 1-3, egg white liquid, and Comparative Examples 1-3 were tested using a texture analyzer. Three tests were conducted, and the average value was calculated. The results are shown in Table 2.

[0064] Table 2. Results of gelation test for different egg white powders

[0065] <![CDATA[Gel strength (g / cm 2 )]]> Example 1 1087 Example 2 1143 Example 3 1268 Egg white liquid 1236 Comparative Example 1 986 Comparative Example 2 894 Comparative Example 3 637

[0066] Comparative Example 4

[0067] The process was carried out in accordance with Example 1, except that in step (4), microwave vacuum freeze drying technology was replaced with hot chamber drying, the drying temperature was 70°C, and the drying time was 21 days.

[0068] Experimental Example 3

[0069] The egg white products prepared in Example 1 and Comparative Example 4 were dissolved in water at ratios of 1g:7mL and 1g:9mL, respectively. The dissolution time was recorded, and the average value was calculated for three trials. The results are shown in Table 3.

[0070] Table 3 Comparison of solubility of different egg white products

[0071]

[0072] As can be seen from Table 3, the dissolution time of Example 1 in water was nearly halved compared to Comparative Example 4, indicating that the dissolution effect of the Example 1 was better.

[0073] Example 4

[0074] Application of high-gel-type egg white products in the preparation of minced meat: The egg white product of Example 1 was added, and the added mass accounted for 5% of the minced meat.

[0075] Method for preparing meat paste using high-gelling egg white powder (process flow see below) Figure 2 The specific steps are as follows:

[0076] (1) Thawing: Thaw at a low temperature of 4℃ or with tap water, with a water temperature <30℃; remove the outer packaging bag of the raw material and put it into the thawing tank. When thawing with water, the raw material must be completely submerged in the water. Handle it gently. After the raw material is put into the thawing tank, the packaging bag must be cleaned immediately to ensure the cleanliness of the workshop; turn the raw material over every half hour during the thawing process. When the water temperature is <10℃, change the water and continue thawing. When the thawing rate is >85%, the thawing can be stopped and the raw material can be taken out.

[0077] (2) Mincing meat: According to the properties of raw materials and processing requirements, the appropriate knives and perforated plates are configured to mince meat into different sizes of meat particles. The temperature of the minced meat is ≤10℃.

[0078] (3) Chopping or beating: Put the minced meat into a chopper or beating machine and stir according to the process requirements. Add 0.3g phosphate, 1.5g salt, 10g ice water, 1.5g egg white product from Example 1, 2g white sugar, 0.5g soy protein, 1g spices, 3g starch, and 6g oil in sequence. Finally, stir evenly and it is ready to be taken out of the pot.

[0079] (4) Forming: Put the pulped material into the pelleting machine, adjust the product specifications and shape parameters, and quickly form pellets;

[0080] (5) Cooking: Place the prepared meatballs in 80℃ water until the center temperature of the meatballs reaches 72℃.

[0081] (6) Cooling: Place the drained meatballs into a quick-freezing machine or quick-freezing line. After quick-freezing, the core temperature is below -15℃.

[0082] Example 5

[0083] The process was carried out in accordance with Example 4, except that the egg white product of Example 1 was replaced with the egg white product of Example 2, and the added mass accounted for 4% of the minced meat product.

[0084] Example 6

[0085] The process was carried out in accordance with Example 4, except that the egg white product of Example 1 was replaced with the egg white product of Example 3, and the added mass accounted for 3% of the minced meat product.

[0086] Compare with Example 1

[0087] The procedure was carried out in accordance with Example 1, except that the egg white product of Example 1 was replaced with egg white liquid.

[0088] Test Example 4

[0089] Using the method of Experimental Example 2, the gelation properties of the minced meat from Examples 4-6 and Control Example 1 were tested, and the results are shown in Table 4.

[0090] Table 4. Results of gelation test for different meat pastes

[0091] <![CDATA[Gel strength (g / cm 2 )]]> Example 4 861 Example 5 834 Example 6 786 Compare with Example 1 798

[0092] As can be seen from Table 4, the gel strength of Example 4 is 861 g / cm³. 2 Example 5 showed a concentration of 834 g / cm³. 2 Example 6 shows a concentration of 786 g / cm³. 2 The gel strength of control example 1 was 798 g / cm³. 2 As can be seen, the gel strength of the minced meat prepared in the examples is higher than that of the egg white liquid, and the gel strength of the product after adding Example 4 is 8% higher than that after adding egg white liquid.

[0093] Therefore, the preparation cycle of the high-gel egg white powder in this invention is as short as 1 day, with low manpower and material resources consumption; the addition of glucose oxidase during the preparation process avoids the off-odor produced by adding yeast for sugar removal; at the same time, microwave vacuum freeze-drying technology further improves the gel strength of the egg white powder; the addition of hydrolyzed rice protein makes the structure of the high-gel egg white powder more stable, and the addition of fish collagen further enriches the functionality of the high-gel egg white powder, making it more cost-effective and functional; in terms of gel strength, the gel strength of the product is increased by 5% to 8% when this product is added to minced meat compared to adding egg white liquid.

[0094] Although the above embodiments have provided a detailed description of the present invention, they are only some embodiments of the present invention, and 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 a high-gel type egg white product, characterized in that, Includes the following steps: Plant protein, animal collagen, and egg white liquid are mixed to obtain a mixture; the mixture is then hydrolyzed with glucose oxidase to obtain an enzymatic hydrolysate; the enzymatic hydrolysate is then dried under low temperature and vacuum using a microwave to obtain a high-gel type egg white product. The plant protein is hydrolyzed rice protein; the animal collagen is fish collagen. The mass ratio of plant protein, animal collagen, and egg white liquid is 12-18:3-8:74-95; The microwave vacuum low-temperature drying process uses a microwave power of 450–550W, a vacuum degree of 1000–2000Pa, a temperature of 15–30℃, and a time of 1–5h.

2. The preparation method according to claim 1, characterized in that, The glucose oxidase added accounts for 0.01% to 0.05% of the total mass of the mixture.

3. The preparation method according to claim 1 or 2, characterized in that, The enzymatic hydrolysis is performed at a temperature of 35–45°C for 3–8 hours.

4. The preparation method according to claim 1, characterized in that, The process before enzymatic hydrolysis also includes adjusting the pH of the mixture to 6.0–7.

0.

5. The preparation method according to claim 1, characterized in that, The enzymatic hydrolysis process also includes enzyme inactivation, which is carried out at a temperature of 35–55°C for 20–40 minutes.

6. A high-gel type egg white product prepared by the preparation method according to any one of claims 1 to 5.

7. The use of the high-gel type egg white product according to claim 6 in the preparation of minced meat.

8. The application according to claim 7, characterized in that, The high-gel type egg white product accounts for 0.1% to 5% of the total mass of the minced meat.

Images