An anti-freezing synergistic complexing agent and its application in preparing instant frozen egg tarts

Abstract

The application discloses an anti-freezing synergic compound and application thereof in preparation of instant frozen egg tarts, and the anti-freezing synergic compound is composed of polar aquatic anti-freezing protein, trehalose and xanthan gum; the mass ratio of the polar aquatic anti-freezing protein, the trehalose and the xanthan gum is 0.01-0.5:20-50:0.01-0.5; the polar aquatic anti-freezing protein is selected from one or more of Antarctic krill anti-freezing protein, Arctic sea ice bacterial anti-freezing protein and sea chub III type anti-freezing protein; the multi-scale synergic effect of the polar aquatic anti-freezing protein, the trehalose and the xanthan gum is utilized, so that the egg tarts have a delicate taste similar to ice cream under the storage condition of-20 DEG C, and can highly restore the softness and elasticity of just baked ones after thawing at normal temperature.

Description

Technical Field

[0001] This invention relates to the field of baking food processing technology, and in particular to an antifreeze synergistic compound and its application in the preparation of ready-to-eat frozen chiffon cakes. Background Technology

[0002] Chiffon cakes are beloved by consumers for their high protein and moisture content, as well as their unique fluffy, spongy texture. With the increasing prevalence of cold chain baking technology, the industry trend is towards storing and transporting pre-made chiffon cakes via cold chain for distribution. However, the unique foam system of chiffon cakes makes them extremely sensitive to the freezing process.

[0003] Chiffon cakes contain numerous porous walls supported by ovalbumin. During frozen storage, temperature fluctuations make the system highly susceptible to ice recrystallization and Ostwald ripening, where tiny ice nuclei spontaneously coalesce into large crystals. Ice crystals formed in ordinary freezing systems are needle-like or plate-like, possessing extremely high mechanical stress. They can directly penetrate and tear the porous walls supported by ovalbumin, causing the sponge-like framework to collapse. As freezing time increases, the strongly bound water in the dough system gradually transforms into weakly bound water or even free water, resulting in a hardened texture and reduced elasticity after thawing, making it impossible to return to its pre-freezing moist state.

[0004] Currently, the industrial practice of adding hydrophilic colloidal emulsifiers or modified starches is common to improve the quality of frozen cakes. However, these additives primarily passively slow down molecular motion by increasing the viscosity of the system, and cannot actively identify and inhibit ice crystal growth at the molecular level. Furthermore, excessive addition of colloids can ruin the original light and airy texture of chiffon cakes, resulting in a pasty consistency.

[0005] Antifreeze proteins (AFPs) are a class of peptides that specifically bind to ice crystals and inhibit their growth. Highly active antifreeze proteins exhibit a unique long-range synergistic effect; their surface threonine arrays induce water molecules within a 1.5 nm radius to form an ordered "ice-like hydration layer," driving the protein to actively diffuse towards the ice crystal front and rapidly adsorb. This adsorption, through the "Kelvin effect," causes the ice crystal surface to bend, thereby significantly lowering the freezing point without altering the melting point (thermal hysteresis effect) and locking the ice crystals in a fine spherulitic state.

[0006] Therefore, developing a preparation technology that utilizes the specific ice crystal modification ability of polar aquatic antifreeze proteins to achieve a preparation technology that allows frozen chiffon cakes to maintain a delicate texture at -20℃ and not collapse after thawing is essential in the current high-end food baking and processing field. Summary of the Invention

[0007] To address the technical problems of existing frozen chiffon cakes, such as hard texture at low temperatures, easy collapse after thawing, severe starch retrogradation, and damaged porosity, this invention provides an antifreeze synergistic compound and its application in the preparation of ready-to-eat frozen chiffon cakes.

[0008] The core idea of ​​this invention is to utilize the multi-scale synergistic effect of polar aquatic antifreeze proteins, trehalose, and xanthan gum to give chiffon cakes a delicate texture similar to ice cream when stored at -20℃, and to highly restore the softness and elasticity of freshly baked cakes after thawing at room temperature.

[0009] The technical solution of the present invention is as follows:

[0010] An antifreeze synergistic compound, composed of polar aquatic antifreeze proteins (AFPs), trehalose, and xanthan gum;

[0011] The mass ratio of polar aquatic antifreeze protein, trehalose, and xanthan gum is 0.01–0.5: 20–50: 0.01–0.5, with a preferred mass ratio of 0.05–0.1: 20–50: 0.01–0.2.

[0012] The polar aquatic antifreeze protein is selected from one or more of Antarctic krill antifreeze protein (EsAFP), Arctic sea ice bacteria antifreeze protein (MaIBP), and sea bream type III antifreeze protein (T3AFP); preferably, a composite protein system with a mass ratio of EsAFP:MaIBP:T3AFP of 2:1:1.

[0013] Based on existing experimental data, under uniform freezing conditions, the antifreeze synergistic compound of this invention can significantly reduce the average diameter of ice crystals, hardness, and thawing collapse rate of cake samples compared to the control sample without the compound system, while maintaining higher elasticity, resilience, and smoothness.

[0014] To ensure the purity and activity of the antifreeze proteins, the three core antifreeze proteins of this invention are extracted and prepared using the following differentiated processes.

[0015] Extraction process of Antarctic krill antifreeze protein (EsAFP) (targeted peptide, molecular weight 14~18kDa):

[0016] Raw material pretreatment: Take frozen Antarctic krill, remove the shell and take the meat, add deionized water at a material-to-liquid ratio of 1:9 (w / w), and homogenize at 10,000 rpm for 5 minutes at 4℃ to fully break down the muscle fibers.

[0017] Weak alkaline extraction and defatting: The pH of the homogenate was adjusted to 11.0 with 1 mol / L NaOH and extracted at low temperature (4℃) with stirring for 4 h; then centrifuged at 4℃, 10000×g for 15 min to remove the bottom insoluble matter and surface lipids, and the supernatant rich in peptides was collected.

[0018] Isoelectric point precipitation to remove impurities: Use 1 mol / L HCl to adjust the pH of the supernatant to 4.5 (isoelectric point of impurity proteins), let stand for 2 hours, centrifuge, and retain the supernatant (containing highly soluble EsAFP).

[0019] Ultrafiltration purification and freeze drying: The supernatant was neutralized to pH 7.0 and passed sequentially through ultrafiltration membranes with molecular weight cutoffs of 30 and 3 kDa. The 3-30 kDa fraction was collected and then freeze-dried under vacuum to obtain freeze-dried Antarctic krill antifreeze protein (EsAFP) powder with high antifreeze activity.

[0020] Extraction process of Arctic sea ice bacterial antifreeze protein (MaIBP):

[0021] Fermentation and cell disruption: Recombinant or wild-type Flavobacterium polaris strains were inoculated into LB cold adaptation medium containing 1% sodium chloride and fermented at 10°C for 48 h; the cells were collected, resuspended in PBS buffer, and thoroughly disrupted using a high-pressure microfluidic homogenizer (1200 bar);

[0022] Affinity chromatography purification: After high-speed centrifugation of the cell wall disruption solution, the supernatant was collected and passed through a nickel ion immobilized metal affinity chromatography column (Ni-NTA). The target protein was eluted using PBS buffer containing 250 mM imidazole.

[0023] Dialysis desalting and lyophilization: The eluent was collected, placed in a 3500 Da dialysis bag, and dialyzed with pure water at 4°C for 24 h to desalt. Then, it was lyophilized to obtain MaIBP powder.

[0024] Recombinant extraction process of type III antifreeze protein (T3AFP) from sea bream:

[0025] Recombinant expression: The synthesized T3AFP gene was transformed into the expression vector using the E. coli (BL21) expression system, and expression was induced by IPTG.

[0026] Thermal denaturation purification: Taking advantage of the extremely high thermal stability of AFP, the cell lysate after high-pressure cell disruption was heated in a 65°C water bath for 30 minutes to denature and precipitate host proteins. The supernatant was then collected by centrifugation.

[0027] Ion exchange: The supernatant was passed through a Q-Sepharose anion exchange chromatography column and eluted with a gradient of 0~1.0 mol / L NaCl. The elution peak was collected, desalted, and lyophilized to obtain T3AFP powder with a purity >95%.

[0028] The antifreeze synergistic compound of this invention can be used to prepare ready-to-eat frozen chiffon cakes. The ready-to-eat frozen chiffon cake is made from the following ingredients in parts by weight:

[0029] 70 parts egg white, 40 parts egg yolk, 40-50 parts low-gluten wheat flour, 5-16 parts corn starch, 20-50 parts white sugar, 35 parts vegetable oil, 35 parts milk, 1-5 parts edible glycerin, 2-6 parts compound emulsifier, 5-50 parts trehalose, 0.01-0.5 parts xanthan gum, 0.01-0.5 parts polar aquatic antifreeze protein.

[0030] Preferably, the ready-to-eat frozen chiffon cake is made from the following ingredients in parts by weight:

[0031] 70 parts egg white, 40 parts egg yolk, 40-45 parts low-gluten wheat flour, 8-13 parts corn starch, 20-50 parts white sugar, 35 parts vegetable oil, 35 parts milk, 1-4 parts edible glycerin, 3-6 parts compound emulsifier, 20-50 parts trehalose, 0.01-0.2 parts xanthan gum, and 0.05-0.1 parts polar aquatic antifreeze protein.

[0032] in,

[0033] The preferred vegetable oil is corn oil;

[0034] The preferred compound emulsifier is SP cake oil, or a food-grade compound emulsifier with the same foaming and foam-stabilizing effects.

[0035] When preparing ready-to-eat frozen chiffon cake, the polar aquatic antifreeze protein is preferably prepared as a solution in citrate buffer (pH=6.8) and added by spraying or fine stream when the meringue is in the wet foaming stage; the concentration of the polar aquatic antifreeze protein solution is preferably 5~10mg / mL; specifically, in the examples, 0.05~0.1g of active protein can be achieved by adding 10g of polar aquatic antifreeze protein solution.

[0036] The preparation method of the ready-to-eat frozen chiffon cake of the present invention includes the following steps:

[0037] S1. Constructing an egg yolk emulsification system:

[0038] Mix low-gluten wheat flour, corn starch, and xanthan gum evenly, and sift (80 mesh) to obtain a mixed powder; mix egg yolks, milk, edible glycerin, and compound emulsifier, and beat with an egg beater until fully emulsified, then add the mixed powder and vegetable oil, and stir evenly to obtain an egg yolk batter;

[0039] In S1, the post-oiling method or the direct emulsification method is adopted. That is, the liquid components and emulsifier are first thoroughly stirred until the volume expands and the color turns white, forming a stable oil-in-water emulsion. Xanthan gum, as a high molecular weight colloid, increases the viscosity of the continuous phase, reduces the diffusion rate of water molecules, and works synergistically with antifreeze proteins to form a viscoelastic protective film at the bubble interface, ensuring that the air cell does not collapse after rewarming.

[0040] S2. Constructing a reinforced foam network:

[0041] Mix granulated sugar and trehalose evenly to obtain a mixed sugar; add the mixed sugar to the egg whites in three batches, and beat with an electric mixer until soft peaks form. Then, add the polar seafood antifreeze egg white solution by spraying and continue beating until stiff peaks form to obtain meringue.

[0042] The specific steps are as follows: Mix the granulated sugar and trehalose evenly to obtain a mixed sugar; use an electric mixer to beat the egg whites until foamy, add 1 / 3 of the mixed sugar, and continue beating until the egg white mixture is fluffy and the foam is delicate, then add another 1 / 3 of the mixed sugar, and continue beating until the egg whites have lines that do not disappear immediately, then add the remaining mixed sugar, and beat until soft peaks form, then add the polar aquatic antifreeze egg white solution using a spray, and continue beating until stiff peaks form, that is, when chopsticks are placed in the egg white mixture, they stand upright and do not fall over;

[0043] In S2, trehalose binds to gluten and ovalbumin via hydrogen bonds at low temperatures, replacing water molecules and forming a high-viscosity glassy matrix that effectively delays the rearrangement and aging of starch molecules. When the egg whites are whipped to "wet foam" (about 6-7 minutes, forming a hook shape when the whisk is lifted), the polar aquatic antifreeze protein solution is slowly added by spraying or a fine stream. At this time, the bubbles are initially formed but not yet stable, and the polar aquatic antifreeze protein molecules quickly diffuse to the gas-liquid interface of the bubbles. The polar aquatic antifreeze protein molecules are amphiphilic (hydrophilic sugar chains and hydrophobic polypeptide chains). They are arranged on the bubble membrane like surfactants, working synergistically with ovalbumin to form a highly resilient "biocomposite membrane." This membrane plays a key physical support role in the subsequent baking expansion and freezing shrinkage.

[0044] S3. Mixing and Baking:

[0045] The egg yolk batter obtained in S1 and the meringue obtained in S2 were mixed using a cutting and folding method. The mixture was poured into a mold and baked at 150℃ for 50 minutes. After baking, the mold was shaken and the cake was inverted and cooled for 2 hours before being unmolded to obtain the cake.

[0046] For example, to use the folding method, add 1 / 3 of the meringue to the egg yolk mixture and fold it in until combined. Then, pour the mixture back into the remaining meringue and fold it in until combined.

[0047] S4. Gradient freezing and ice crystal modification:

[0048] After the cake has cooled to room temperature, it undergoes two stages of freezing: Stage 1: Freeze at -40℃ for 12~48 hours; Stage 2: Transfer to a -20℃ cold storage for storage.

[0049] In S4, the first stage is the nucleation period, during which the system is quick-frozen at -40℃ for 12-48 hours, during which a large number of tiny ice nuclei are formed instantly. The second stage is the growth period control, during which the system is transferred to a -20℃ cold storage. During the cooling process, polar aquatic antifreeze protein molecules (AFPs) dispersed in free water recognize and irreversibly adsorb onto the non-basal planes (prismatic or pyramidal faces) of ice crystals. AFPs form hydrogen bonds with oxygen atoms on the surface of ice crystals through the hydroxyl groups on their sugar side chains. This adsorption causes the ice crystal growth front to exhibit a slightly curved surface, forcing the ice crystals to expand laterally at even lower temperatures. Thus, at the actual temperature of -20℃, the ice crystals are "locked" in a tiny size and cannot grow into large needle-like crystals.

[0050] The technical principles of this invention include:

[0051] This invention proposes an antifreeze synergistic compound, composed of polar aquatic antifreeze proteins (AFPs), trehalose, and xanthan gum. The antifreeze proteins are derived from polar cold-water fish or crustaceans and have significant ice crystal growth inhibition (IRI) activity and thermal hysteresis (TH) activity, enabling them to specifically recognize and adsorb onto specific crystal surfaces of tiny ice crystals. The preferred addition amounts of each component in the chiffon cake batter system are: AFPs 0.01%~0.05% (more preferably 0.02%~0.04%), trehalose 3%~8% (partially replacing the white sugar in the original formula), and xanthan gum 0.05%~0.2%.

[0052] Synergistic mechanism of compounding: This invention innovatively constructs a foam-aqueous dual-carrier system based on "targeted adsorption of multi-source protein polycrystalline surfaces":

[0053] Multifaceted Synergistic Locking: Antifreeze proteins from different sources exhibit strong complementarity in their adsorption sites on ice crystals. Specifically, Antarctic krill antifreeze protein (EsAFP, major molecular weight 1-20 kDa) primarily encapsulates the surface of tiny ice nuclei; Arctic sea bacteria antifreeze protein (MaIBP), due to its ultra-high thermal hysteresis activity, specifically pins to the basal surface of ice crystals; and pufferfish type III antifreeze protein (T3AFP) adsorbs onto the prismatic facets of ice crystals. When these three are combined in a specific ratio, they form a comprehensive "three-dimensional envelopment" of the ice crystal, resulting in an efficacy far exceeding that of single-source antifreeze proteins in inhibiting ice recrystallization (IRI).

[0054] The micro-macro-microscopic synergy of sugar, gum, and protein: Trehalose forms a high Tg' glassy matrix to protect gluten proteins; xanthan gum increases liquid phase viscosity and forms a viscoelastic membrane on the pore walls; and the complex antifreeze protein completely modifies destructive long needle-shaped ice crystals into harmless micron-sized spherical crystals at the microscopic level. These three elements work together to give the cake a perfectly smooth, ice cream-like texture at -20°C.

[0055] Compared with the prior art, the present invention has the following significant advantages:

[0056] (1) Excellent frozen texture: Due to the ice recrystallization inhibition activity of antifreeze proteins, after storage at -20℃, the average diameter of ice crystals inside the cake is controlled within 20~40μm (far below the threshold of roughness of the human tongue). When eaten, the fine ice crystals melt instantly, giving the cake a smooth and delicate texture like ice cream, without any ice crystals.

[0057] (2) Zero collapse and perfect restoration: By protecting the integrity of the bubble walls, the specific volume loss rate of the cake after thawing is less than 2% compared with that before freezing. Texture analyzer (TPA) test showed that the hardness and elasticity of the thawed cake were not significantly different from those of the fresh cake (P>0.05), which solved the problem of collapse and densification of traditional frozen chiffon cakes after thawing, which are "like wet cotton".

[0058] (3) Inhibition of starch retrogradation and water retention preservation: Low-field nuclear magnetic resonance (LF-NMR) detection confirmed that the present invention effectively reduces the precipitation of free water during freezing and locks water molecules in a weakly bound water state. This not only prevents moisture loss, but also significantly delays the starch retrogradation process, so that the cake remains moist and soft after thawing at room temperature and does not crumble. Attached Figure Description

[0059] Figure 1 : Schematic diagram of the microstructure of a frozen chiffon cake stored at -20℃; Left: Comparative Example 1, Right: Example 4. Detailed Implementation

[0060] The present invention is further described below through specific embodiments, but the scope of protection of the present invention is not limited thereto.

[0061] The raw material formulations for the following examples and comparative examples are shown in Table 1.

[0062] Table 1. Component content of examples and comparative examples

[0063]

[0064] Among them, functional additives A, B, C, and D are polar aquatic antifreeze protein solutions, and their preparation methods are as follows:

[0065] Functional additive A is an Antarctic krill antifreeze protein (EsAFP) solution (10mg / mL): Accurately weigh 1.00g of EsAFP lyophilized powder, slowly add it to 80mL of pH 6.8 citrate buffer solution, stir magnetically for 30min until completely dissolved, and bring the volume up to 100mL.

[0066] Functional additive B is an Arctic sea ice bacterial antifreeze protein (MaIBP) solution (5 mg / mL): Accurately weigh 0.50 g of lyophilized MaIBP powder and slowly add it to 80 mL of pH 6.8 citrate buffer solution. Stir magnetically for 30 min until completely dissolved, then bring the volume to 100 mL. (It should be noted that MaIBP is a highly active AFP, therefore the amount of MaIBP added is significantly lower than that of ordinary AFP).

[0067] Functional additive C is a solution of type III antifreeze protein (T3AFP) from sea bream (10 mg / mL): Accurately weigh 1.00 g of T3AFP lyophilized powder, slowly add it to 80 mL of pH 6.8 citrate buffer, stir magnetically for 30 min until completely dissolved, and bring the volume up to 100 mL.

[0068] Functional additive D is a synergistic complex solution (8mg / mL): Prepare a container, add 50mL of citrate buffer solution with pH 6.8, weigh 0.40g of EsAFP powder, 0.20g of MaIBP powder and 0.20g of T3AFP powder respectively, add them to the citrate buffer solution in sequence and stir magnetically to dissolve. After mixing evenly, bring the volume to 100mL.

[0069] The SP cake oil used in the following examples comes from Hongyuan Baking Ingredients physical store. The product name is Zaomiao SP Cake Oil. The ingredient list includes mono- and diglyceride fatty acid esters, sorbitol liquid, propylene glycol, sucrose fatty acid esters, sorbitan monostearate, etc.

[0070] The egg beater was purchased from the Little Bear Life flagship store on Taobao, model number DDQ-D01U1-1.

[0071] Example 1

[0072] The ingredients are as follows: 70g egg whites, 40g egg yolks, 45g low-gluten wheat flour, 10g corn starch, 10g trehalose, 30g white sugar, 35g corn oil, 35g milk, 2g edible glycerin, 4g SP cake oil, 0.1g xanthan gum, and 10g functional additive A.

[0073] A method for preparing a chiffon cake that maintains a soft texture while frozen includes the following steps:

[0074] S1. Accurately weigh 45g of low-gluten wheat flour, 10g of corn starch, and 0.1g of xanthan gum, mix them, and pass them through an 80-mesh sieve to obtain a mixed powder;

[0075] S2. Accurately weigh 40g egg yolks, 35g milk, 2g edible glycerin, and 4g SP cake oil. Beat with an electric mixer on speed 1 for 2 minutes until emulsified and white. Add the mixed powder and 35g corn oil, and stir well to obtain the egg yolk batter.

[0076] S3. Accurately weigh 70g of egg whites, mix 10g of trehalose and 30g of white sugar and add them to the egg whites in three batches. Beat with an electric mixer on the lowest speed until soft peaks form. Then, spray 10g of functional additive A evenly into the meringue and continue beating until stiff peaks form (short, upright peaks).

[0077] S4. Use a folding motion to mix the egg yolk batter and meringue. Pour into a 6-inch anodized mold and tap to release any large air bubbles. Bake in a preheated oven at 150°C (300°F) for 50 minutes. Remove from the oven, tap the mold to release air bubbles, invert, and let cool for 2 hours before unmolding.

[0078] S5. Seal and freeze in a -40℃ freezer for 24 hours, then transfer to a -20℃ cold storage for 7 days.

[0079] Example 2

[0080] The ingredients are as follows: 70g egg whites, 40g egg yolks, 50g low-gluten wheat flour, 5g corn starch, 10g trehalose, 30g white sugar, 35g corn oil, 35g milk, 2g edible glycerin, 4g SP cake oil, 0.1g xanthan gum, and 10g functional additive B1.

[0081] A method for preparing a chiffon cake that maintains a soft texture while frozen includes the following steps:

[0082] S1. Accurately weigh 50g of low-gluten wheat flour, 5g of corn starch, and 0.1g of xanthan gum, mix them, and pass them through an 80-mesh sieve to obtain a mixed powder;

[0083] S2. Accurately weigh 40g egg yolks, 35g milk, 2g edible glycerin, and 4g SP cake oil. Beat with an electric mixer on speed 1 for 2 minutes until emulsified and white. Add the mixed powder and 35g corn oil, and stir well to obtain the egg yolk batter.

[0084] S3. Accurately weigh 70g of egg whites, mix 10g of trehalose and 30g of white sugar and add them to the egg whites in three batches. Beat with an electric mixer on the lowest speed until soft peaks form. Then, spray 10g of functional additive B evenly into the meringue and continue beating until stiff peaks form (short, upright peaks).

[0085] S4. Use a folding motion to mix the egg yolk batter and meringue. Pour into a 6-inch anodized mold and tap to release any large air bubbles. Bake in a preheated oven at 150°C (300°F) for 50 minutes. Remove from the oven, tap the mold to release air bubbles, invert, and let cool for 2 hours before unmolding.

[0086] S5. Seal and freeze in a -40℃ freezer for 12 hours, then transfer to a -20℃ cold storage for 7 days.

[0087] Example 3

[0088] The ingredients are as follows: 70g egg whites, 40g egg yolks, 45g low-gluten wheat flour, 10g corn starch, 20g trehalose, 20g white sugar, 35g corn oil, 35g milk, 3g edible glycerin, 3g SP cake oil, 0.1g xanthan gum, and 10g functional additive C.

[0089] A method for preparing a chiffon cake that maintains a soft texture while frozen includes the following steps:

[0090] S1. Accurately weigh 45g of low-gluten wheat flour, 10g of corn starch, and 0.1g of xanthan gum, mix them, and pass them through an 80-mesh sieve to obtain a mixed powder;

[0091] S2. Accurately weigh 40g egg yolks, 35g milk, 2g edible glycerin, and 4g SP cake oil. Beat with an electric mixer on speed 1 for 2 minutes until emulsified and white. Add the mixed powder and 35g corn oil, and stir well to obtain the egg yolk batter.

[0092] S3. Accurately weigh 70g of egg whites, mix 20g of trehalose and 20g of granulated sugar and add them to the egg whites in three batches. Beat with an electric mixer on the lowest speed until soft peaks form. Then, spray 10g of functional additive C evenly into the meringue and continue beating until stiff peaks form (short, upright peaks).

[0093] S4. Use a folding motion to mix the egg yolk batter and meringue. Pour into a 6-inch anodized mold and tap to release any large air bubbles. Bake in a preheated oven at 150°C (300°F) for 50 minutes. Remove from the oven, tap the mold to release air bubbles, invert, and let cool for 2 hours before unmolding.

[0094] S5. Seal and freeze in a -40℃ freezer for 24 hours, then transfer to a -20℃ cold storage for 2 days.

[0095] Example 4

[0096] The ingredients are as follows: 70g egg whites, 40g egg yolks, 45g low-gluten wheat flour, 10g corn starch, 20g trehalose, 20g white sugar, 35g corn oil, 35g milk, 2g edible glycerin, 4g SP cake oil, 0.2g xanthan gum, and 10g functional additive D.

[0097] A method for preparing a chiffon cake that maintains a soft texture while frozen includes the following steps:

[0098] S1. Accurately weigh 45g of low-gluten wheat flour, 10g of corn starch, and 0.2g of xanthan gum, mix them, and pass them through an 80-mesh sieve to obtain a mixed powder;

[0099] S2. Accurately weigh 40g egg yolks, 35g milk, 2g edible glycerin, and 4g SP cake oil. Beat with an electric mixer on speed 1 for 2 minutes until emulsified and white. Add the mixed powder and 35g corn oil, and stir well to obtain the egg yolk batter.

[0100] S3. Accurately weigh 70g of egg whites, mix 20g of trehalose and 20g of granulated sugar and add them to the egg whites in three batches. Beat with an electric mixer on the lowest speed until soft peaks form. Then, spray 10g of functional additive D evenly into the meringue and continue beating until stiff peaks form (short, upright peaks).

[0101] S4. Use a folding motion to mix the egg yolk batter and meringue. Pour into a 6-inch anodized mold and tap to release any large air bubbles. Bake in a preheated oven at 150°C (300°F) for 50 minutes. Remove from the oven, tap the mold, invert, and let cool for 2 hours before unmolding.

[0102] S5. Seal and freeze in a -40℃ freezer for 24 hours, then transfer to a -20℃ cold storage for 4 days.

[0103] Example 5

[0104] The ingredients are as follows: 70g egg whites, 40g egg yolks, 50g low-gluten wheat flour, 5g corn starch, 30g trehalose, 10g white sugar, 35g corn oil, 35g milk, 3g edible glycerin, 3g SP cake oil, 0.2g xanthan gum, and 10g functional additive D.

[0105] A method for preparing a chiffon cake that maintains a soft texture while frozen includes the following steps:

[0106] S1. Accurately weigh 45g of low-gluten wheat flour, 10g of corn starch, and 0.2g of xanthan gum, mix them, and pass them through an 80-mesh sieve to obtain a mixed powder;

[0107] S2. Accurately weigh 40g egg yolks, 35g milk, 2g edible glycerin, and 4g SP cake oil. Beat with an electric mixer on speed 1 for 2 minutes until emulsified and white. Add the mixed powder and 35g corn oil, and stir well to obtain the egg yolk batter.

[0108] S3. Accurately weigh 70g of egg whites, mix 30g of trehalose and 10g of white sugar and add them to the egg whites in three batches. Beat with an electric mixer on the lowest speed until soft peaks form. Then, spray 10g of functional additive D evenly into the meringue and continue beating until stiff peaks form (short, upright peaks).

[0109] S4. Use a folding motion to mix the egg yolk batter and meringue. Pour into a 6-inch anodized mold and tap to release any large air bubbles. Bake in a preheated oven at 150°C (300°F) for 50 minutes. Remove from the oven, tap the mold to release air bubbles, invert, and let cool for 2 hours before unmolding.

[0110] S5. Seal and freeze in a -40℃ freezer for 12 hours, then transfer to a -20℃ cold storage for 6 days.

[0111] Example 6

[0112] The ingredients are as follows: 70g egg whites, 40g egg yolks, 48g low-gluten wheat flour, 7g corn starch, 30g trehalose, 40g white sugar, 35g corn oil, 35g milk, 3g edible glycerin, 4g SP cake oil, 0.2g xanthan gum, and 10g functional additive D.

[0113] A method for preparing a chiffon cake that maintains a soft texture while frozen includes the following steps:

[0114] S1. Accurately weigh 45g of low-gluten wheat flour, 10g of corn starch, and 0.2g of xanthan gum, mix them, and pass them through an 80-mesh sieve to obtain a mixed powder;

[0115] S2. Accurately weigh 40g egg yolks, 35g milk, 2g edible glycerin, and 4g SP cake oil. Beat with an electric mixer on speed 1 for 2 minutes until emulsified and white. Add the mixed powder and 35g corn oil, and stir well to obtain the egg yolk batter.

[0116] S3. Accurately weigh 70g of egg whites, mix 30g of trehalose and 10g of white sugar and add them to the egg whites in three batches. Beat with an electric mixer on the lowest speed until soft peaks form. Then, spray 10g of functional additive D evenly into the meringue and continue beating until stiff peaks form (short, upright peaks).

[0117] S4. Use a folding motion to mix the egg yolk batter and meringue. Pour into a 6-inch anodized mold and tap to release any large air bubbles. Bake in a preheated oven at 150°C (300°F) for 50 minutes. Remove from the oven, tap the mold to release air bubbles, invert, and let cool for 2 hours before unmolding.

[0118] S5. Seal and freeze in a -40℃ freezer for 36 hours, then transfer to a -20℃ cold storage for 8 days.

[0119] Comparative Example 1

[0120] The ingredients are as follows: 70g egg whites, 40g egg yolks, 45g low-gluten wheat flour, 10g corn starch, 40g white sugar, 35g corn oil, 35g milk, 2g edible glycerin, 4g SP cake oil, and 10g citrate buffer solution with pH 6.8.

[0121] The difference between this comparative example and Example 4 is that the antifreeze protein solution is replaced with an equal volume of distilled water, and trehalose and xanthan gum are not added. The steps include:

[0122] S1. Accurately weigh 45g of low-gluten wheat flour and 10g of corn starch, mix them, and pass them through an 80-mesh sieve to obtain the mixed powder;

[0123] S2. Accurately weigh 40g egg yolks, 35g milk, 2g edible glycerin, and 4g SP cake oil. Beat with an electric mixer on speed 1 for 2 minutes until emulsified and white. Add the mixed powder and 35g corn oil, and stir well to obtain the egg yolk batter.

[0124] S3. Accurately weigh 70g of egg whites, add 40g of granulated sugar to the egg whites in three batches, beat with an electric mixer on the lowest speed until soft peaks form, then spray 10g of citric acid buffer evenly into the meringue, and continue beating until stiff peaks form (short, upright peaks).

[0125] S4. Use a folding motion to mix the egg yolk batter and meringue. Pour into a 6-inch anodized mold and tap to release any large air bubbles. Bake in a preheated oven at 150°C (300°F) for 50 minutes. Remove from the oven, tap the mold to release air bubbles, invert, and let cool for 2 hours before unmolding.

[0126] S5. Seal and freeze in a -40℃ freezer for 24 hours, then transfer to a -20℃ cold storage for 7 days.

[0127] Comparative Example 2

[0128] The raw material composition is as follows (completely consistent with Example 4): 70g egg white, 40g egg yolk, 45g low-gluten wheat flour, 10g corn starch, 20g trehalose, 20g white sugar, 35g corn oil, 35g milk, 2g edible glycerin, 4g SP cake oil, 0.2g xanthan gum, and 10g functional additive D.

[0129] The difference between this comparative example and Example 4 is that functional additive D is directly added to the egg yolk mixture, including the following steps:

[0130] S1. Accurately weigh 45g of low-gluten wheat flour, 10g of corn starch, and 0.2g of xanthan gum, mix them, and pass them through an 80-mesh sieve to obtain a mixed powder;

[0131] S2. Accurately weigh 40g egg yolks, 35g milk, 2g edible glycerin, 4g SP cake oil, and functional additive D. Beat with an egg beater on speed 1 for 2 minutes until emulsified and white. Add the mixed powder and 35g corn oil, and stir well to obtain the egg yolk batter.

[0132] S3. Accurately weigh 70g of egg whites, mix 20g of trehalose and 20g of granulated sugar and add them to the egg whites in three batches, and continue to beat until stiff peaks form (short, upright peaks).

[0133] S4. Use a folding motion to mix the egg yolk batter and meringue. Pour into a 6-inch anodized mold and tap to release any large air bubbles. Bake in a preheated oven at 150°C (300°F) for 50 minutes. Remove from the oven, tap the mold to release air bubbles, invert, and let cool for 2 hours before unmolding.

[0134] S5. Seal and freeze in a -40℃ freezer for 36 hours, then transfer to a -20℃ cold storage for 4 days.

[0135] To ensure the rigor of the horizontal comparison, Examples 1-4 and Comparative Examples 1-2 all used the same baking and freezing conditions in the tests corresponding to Table 2; Examples 5 and 6 are used to illustrate the feasibility and performance trends when the formulation and process boundaries change.

[0136] Table 2. Ice crystal analysis, textural properties, and mouthfeel rating under -20℃ frozen conditions.

[0137]

[0138] Experimental data shows:

[0139] 1. Polycrystalline spatial targeted adsorption and ice crystal morphology modification (microscopic and DSC analysis):

[0140] The freezeable water content measured by differential scanning calorimetry (DSC) directly reflects the system's antifreeze capability. In Comparative Example 1, the ice crystal diameter reached as high as 125.4 μm, with long-growing needle-like ice crystals piercing the gluten network. In Example 4, due to the polycrystalline synergistic locking effect of the composite antifreeze protein system (auxiliary agent D)—EsAFP encapsulating the microscopic core surface, MaIBP pinning the basal surface, and T3AFP adsorbing the prismatic surface—a three-dimensional enveloping effect was formed. This significantly reduced the freezeable water content to 41.2%, forcibly "locking" the ice crystals into a microsphere state of 18.2 μm (below the human oral sensory roughness threshold of 25 μm), thus giving the cake a perfect "ice cream" texture.

[0141] 2. Inhibition of water migration and bound water lock-in (LF-NMR analysis):

[0142] Low-field nuclear magnetic resonance (LF-NMR) transverse relaxation time (T2) data showed that the total relative content of strongly bound water and weakly bound water in Example 4 (P0.05) was significantly lower. 21 The concentration of trehalose was as high as 46.7%, far exceeding the 15.2% of Comparative Example 1. This is not only due to the effect of antifreeze proteins, but also a result of the synergistic physical glass transition of trehalose and xanthan gum. Trehalose increased the maximum glass transition temperature (T0) of the system at low temperatures. g ' It forms a high-density hydrogen bond network with gluten protein, forcibly anchoring water molecules.

[0143] 3. Macroscopic framework protection and texture reduction (TPA analysis and process validation of Comparative Example 2):

[0144] The hardness and elasticity indices of a texture analyzer (TPA) are directly related to the consumer's chewing experience. Although Comparative Example 2 included a complex antifreeze protein, the addition of AFP to the egg yolk mixture (away from the bubble interface) resulted in a thawing collapse rate as high as 16.8%, and an elasticity that plummeted to 0.72. Conversely, Example 4 achieved precise spraying during the S2 wet foaming stage, allowing the amphiphilic AFP to precisely embed itself at the gas-liquid interface like a surfactant, replacing some of the less polar water molecules. After thawing, the elasticity reached 0.98, and the hardness was only 168.5, perfectly achieving the ideal texture of "room temperature recovery - zero collapse."

[0145] in conclusion:

[0146] The three-dimensional synergistic system constructed in this invention, consisting of "Antarctic krill and other composite antifreeze peptides + trehalose vitrification matrix + xanthan gum rheological barrier", completely overcomes the industry pain point of cold chain texture aging in chiffon cakes from three dimensions: thermodynamic crystallization control, interfacial physical enhancement, and macromolecular rheology. It has extremely high potential for technology transfer and industrialization.

Claims

1. An antifreeze synergistic compound, characterized in that, It is composed of polar aquatic antifreeze protein, trehalose, and xanthan gum; the mass ratio of polar aquatic antifreeze protein, trehalose, and xanthan gum is 0.01-0.5: 20-50: 0.01-0.

5. The polar aquatic antifreeze protein is selected from one or more of the following: Antarctic krill antifreeze protein, Arctic sea ice bacteria antifreeze protein, and sea bream type III antifreeze protein.

2. The antifreeze synergistic compound agent as described in claim 1, characterized in that, The polar aquatic antifreeze protein is a composite protein system consisting of Antarctic krill antifreeze protein, Arctic sea ice bacteria antifreeze protein, and sea bream type III antifreeze protein in a mass ratio of 2:1:

1.

3. The application of the antifreeze synergistic compound as described in claim 1 in the preparation of ready-to-eat frozen chiffon cake.

4. A ready-to-eat frozen chiffon cake, characterized in that, Made from the following parts by weight of raw materials: 70 parts egg white, 40 parts egg yolk, 40-50 parts low-gluten wheat flour, 5-16 parts corn starch, 20-50 parts white sugar, 35 parts vegetable oil, 35 parts milk, 1-5 parts edible glycerin, 2-6 parts compound emulsifier, 5-50 parts trehalose, 0.01-0.5 parts xanthan gum, 0.01-0.5 parts polar aquatic antifreeze protein.

5. The ready-to-eat frozen chiffon cake as described in claim 4, characterized in that, The vegetable oil selected is corn oil.

6. The ready-to-eat frozen chiffon cake as described in claim 4, characterized in that, The compound emulsifier is selected from SP cake oil.

7. The ready-to-eat frozen chiffon cake as described in claim 4, characterized in that, The polar aquatic antifreeze protein is prepared as a polar aquatic antifreeze protein solution using a citrate buffer solution at pH 6.

8.

8. The ready-to-eat frozen chiffon cake as described in claim 7, characterized in that, The concentration of polar aquatic antifreeze protein solution is 5~10 mg / mL.

9. The method for preparing the ready-to-eat frozen chiffon cake as described in claim 4, characterized in that, Includes the following steps: S1. Constructing an egg yolk emulsification system: Mix low-gluten wheat flour, corn starch, and xanthan gum evenly, sift, and obtain mixed powder; mix egg yolks, milk, edible glycerin, and compound emulsifier, beat with an egg beater until fully emulsified, then add mixed powder and vegetable oil, stir well, and obtain egg yolk batter; S2. Constructing a reinforced foam network: Mix granulated sugar and trehalose evenly to obtain a mixed sugar; add the mixed sugar to the egg whites in three batches, and beat with an electric mixer until soft peaks form. Then, add the polar seafood antifreeze egg white solution by spraying and continue beating until stiff peaks form to obtain meringue. S3. Mixing and Baking: The egg yolk batter obtained in S1 and the meringue obtained in S2 were mixed using a cutting and folding method. The mixture was poured into a mold and baked at 150℃ for 50 minutes. After baking, the mold was shaken and the cake was inverted and cooled for 2 hours before being unmolded to obtain the cake. S4. Gradient freezing and ice crystal modification: After the cake cools to room temperature, it undergoes two stages of freezing: Stage 1: Freeze at -40℃ for 12~48 hours; Stage 2: Transfer to a -20℃ cold storage.

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