High-temperature-resistant natural milk-flavored essence as well as preparation method and application thereof

Abstract

The invention belongs to the field of novel food flavors, and particularly discloses a high-temperature-resistant natural milk flavor as well as a preparation method and application thereof, and the high-temperature-resistant natural milk flavor comprises the following components: 10-30 parts of butter enzymatic hydrolysate, 80-150 parts of reconstituted milk enzymatic hydrolysate, 20-30 parts of whey protein powder, 100-130 parts of maltodextrin, 100-120 parts of composite modified starch, 1-5 parts of a high-temperature protective agent and 300-500 parts of deionized water. The preparation method comprises the following steps: respectively preparing butter enzymatic hydrolysate and reconstituted milk enzymatic hydrolysate; mixing and emulsifying the whey protein powder and the composite modified starch with a wall material system consisting of the whey protein powder, the maltodextrin and the composite modified starch, homogenizing and sterilizing, and spray-drying to obtain the whey protein powder. The composite modified starch is prepared by performing octenyl succinic anhydride esterification and sodium trimetaphosphate cross-linking composite modification on cassava raw starch. Through the synergistic effect of composite enzymolysis, a specific wall material system and a high-temperature protective agent, the industrial problems that the fragrance of the natural milk-flavored essence is easy to lose and the flavor is unstable during high-temperature processing are successfully solved.

Description

TECHNICAL FIELD

[0001] The application belongs to the field of novel food essence, and specifically discloses a high-temperature-resistant natural milk flavor essence as well as a preparation method and application thereof. BACKGROUND

[0002] With the upgrading of consumption and high attention to the health attributes of food, the market demand for natural and clean-label food additives continues to grow. As a key component for improving the flavor quality of food, the naturalization and functionalization of essence have become an irreversible development trend. Milk flavor essence is widely used in dairy products, baked foods, beverages, candies, ice cream and other products due to its rich milk flavor and wide application, so as to enhance the flavor, improve the taste and enhance the overall acceptance of the products.

[0003] At present, the milk flavor essences available on the market mainly include the following categories:

[0004] Chemically synthesized milk flavor essence simulates milk flavor by artificially synthesizing flavor substances such as butanedione and acetylpropionic acid. Although it has low cost and high aroma intensity, its "non-natural" attribute is contrary to the current health consumption concept. More importantly, the molecular structure of such essence is unstable under high temperature conditions, and it is extremely easy to volatilize, decompose or undergo Maillard reaction during the heat treatment such as baking and sterilization, resulting in a large loss of aroma and even the generation of unpleasant chemical odor, which seriously limits its application in high-temperature processed foods.

[0005] Natural extraction milk flavor essence is mainly obtained from natural milk sources such as milk and cream through physical methods such as distillation and extraction. Although it is natural and meets the requirements of clean label, it has inherent disadvantages such as low extraction efficiency, high cost and generally weak aroma intensity. At the same time, the natural flavor components in such essence are also sensitive to heat, and the problem of poor heat resistance has not been effectively solved, and the essence is prone to aroma distortion and short aroma retention time during high-temperature processing.

[0006] Milk flavor prepared by enzymatic hydrolysis or fermentation is a hot research topic at present. This technology uses lipase, protease or specific microorganisms to biotransform substrates such as milk fat and milk protein to generate a series of natural flavor compounds such as lactic acid and ethyl butyrate. This method improves the natural properties of aroma and the rich levels of flavor to some extent, and is considered to be one of the most promising natural flavor preparation routes. However, the existing enzymatic hydrolysis / fermentation technology still has obvious limitations: first, its high-temperature resistance has not been fundamentally broken through, and many key flavor substances are still prone to oxidation and decomposition at high temperatures, resulting in flavor attenuation in application; second, the enzymatic hydrolysis process (such as enzyme selection, compound ratio, and reaction conditions) often lacks systematic optimization, making it difficult to precisely control the formation path of flavor, resulting in poor batch stability and single flavor dimension, lacking the complexity and richness of natural milk fat; third, most research results are still in the laboratory stage, and the process scaling feasibility, cost controllability, and application performance (such as solubility, flowability, and stability) of the final product have not been fully verified and solved.

[0007] In addition, the existing natural milk flavor generally lacks effective protection technology for high-temperature application scenarios. When applied to baked products, UHT sterilized milk, high-temperature filled beverages, etc., how to prevent flavor components from rapidly escaping and deteriorating during processing and storage is a core technical bottleneck that the industry has been facing for a long time. This directly leads to problems such as insufficient aroma persistence, flavor distortion, and odor generation, which seriously restricts the development and application of high-quality natural milk flavor.

[0008] Therefore, the food industry urgently needs to develop a new technical solution that can fundamentally overcome the above-mentioned defects. The ideal product should have the following characteristics: completely natural raw materials, full and harmonious flavor, excellent high-temperature resistance, and stable production process that can be industrialized. This is not only the key to meeting market demand, but also has great significance for promoting the technological progress of the entire natural food flavor industry. SUMMARY

[0009] To solve the above problems, the present application discloses a high-temperature-resistant natural milk flavor and its preparation method and application.

[0010] The present application includes the following technical solutions:

[0011] A high-temperature-resistant natural milk flavor, comprising the following components by weight:

[0012] Butter enzymatic hydrolysate: 10-30 parts;

[0013] Reconstituted milk enzymatic hydrolysate: 80-150 parts;

[0014] Whey protein powder: 20-30 parts;

[0015] Maltodextrin: 100-130 parts;

[0016] Complex modified starch: 100-120 parts; the complex modified starch is prepared by esterification of cassava native starch with octenyl succinic anhydride and cross-linking with sodium trimetaphosphate through a complex modification process;

[0017] High-temperature protective agent: 1-5 parts;

[0018] Deionized water: 300-500 parts.

[0019] Further, the above-mentioned high-temperature-resistant natural milk flavor essence, the preparation method of the complex modified starch comprises the following steps:

[0020] (1) The cassava native starch is prepared into a slurry of 35-40%, and 3-5% of sodium chloride based on the dry mass of the starch is added as a coagulation inhibitor, and stirred uniformly;

[0021] (2) The pH of the system is adjusted to 8.5-9.0 with 2-4% of sodium hydroxide solution, and 2-4% of octenyl succinic anhydride based on the dry mass of the starch is slowly added under continuous stirring, the pH is maintained at 8.5-9.0 with alkali solution during the reaction, the reaction temperature is controlled at 30-35℃, and the reaction time is 4-6 hours;

[0022] (3) After the esterification is completed, stirring is maintained, 0.5-1.2% of sodium trimetaphosphate based on the dry mass of the starch is added, the pH is adjusted and maintained at 11.0-11.5 with alkali solution, the temperature is raised to 45-50℃, and the cross-linking reaction is carried out for 1-2 hours;

[0023] (4) After the reaction is completed, the pH is adjusted to 5.5-6.5 with hydrochloric acid to terminate the reaction, and the complex modified starch is obtained after washing, filtering, drying, and crushing.

[0024] Further, the above-mentioned high-temperature-resistant natural milk flavor essence, the butter enzymatic solution is obtained by complex enzymolysis of at least two kinds of lipase, the lipase is selected from two or three of 1,3-site specific lipase derived from Rhizomucor miehei, non-specific lipase derived from Candida rugosa, and lipase derived from Aspergillus niger, the total amount of enzyme addition is 0.1-0.5% of the butter, the enzymolysis temperature is 45-55℃, and the enzymolysis time is 4-6 hours

[0025] Preferably, the lipase is selected from two or three of AMANO AY30SD (this enzyme is a 1,3-position specific lipase derived from Rhizomucor miehei. It is characterized by specific hydrolysis of the 1 and 3 ester bonds of triglycerides to produce free fatty acids and diglycerides, and is a key enzyme for the production of butter flavor by enzymatic hydrolysis of butter, especially short-chain fatty acids such as butyric acid), AMANO MER (this enzyme is a non-specific lipase derived from Candida rugosa. It is characterized by hydrolysis activity on the 1, 2, and 3 positions of triglycerides, and can more comprehensively release free fatty acids of various chain lengths, helping to form more complex and rich milk and fat flavors), and AMANO A12 (this enzyme is a lipase (with esterase activity) derived from Aspergillus niger. Its enzyme activity is relatively mild, and helps to produce some pleasant ester aroma substances, making the overall flavor more mellow and closer to natural cow's milk), with a total enzyme addition amount of 0.1-0.5% of the butter, an enzyme hydrolysis temperature of 45-55°C, and an enzyme hydrolysis time of 4-6 hours.

[0026] Further, in the above-mentioned natural milk flavor essence with high temperature resistance, the enzyme activity ratio of the 1,3-position specific lipase derived from Rhizomucor miehei, the non-specific lipase derived from Candida rugosa, and the lipase derived from Aspergillus niger in the butter enzyme hydrolysate is (1-2):(1-2):(1-3).

[0027] Preferably, in the above-mentioned natural milk flavor essence with high temperature resistance, the enzyme activity ratio of AMANO AY30SD, AMANO MER, and AMANO A12 in the butter enzyme hydrolysate is (1-2):(1-2):(1-3).

[0028] Further, in the above-mentioned natural milk flavor essence with high temperature resistance, the reconstituted milk enzyme hydrolysate is obtained by co-enzymatic hydrolysis of reconstituted milk with a complex protease and a lipase, wherein the protease is trypsin or neutral protease, and the lipase is a 1,3-position specific lipase derived from Rhizomucor miehei or a non-specific lipase derived from Candida rugosa, the enzyme hydrolysis temperature is 45-50°C, and the enzyme hydrolysis time is 4-6 hours.

[0029] Preferably, in the above-mentioned natural milk flavor essence with high temperature resistance, the reconstituted milk enzyme hydrolysate is obtained by co-enzymatic hydrolysis of reconstituted milk with a complex protease and a lipase, wherein the protease is trypsin or neutral protease, and the lipase is AMANO AY30SD or AMANO MER, the enzyme hydrolysis temperature is 45-50°C, and the enzyme hydrolysis time is 4-6 hours.

[0030] Further, the high-temperature resistant natural milk flavor essence has the high-temperature protective agent which is compounded by gum arabic and beta-cyclodextrin at a mass ratio of (1:1) to (2:1).

[0031] The application further discloses a preparation method of the high-temperature resistant natural milk flavor essence.

[0032] S1, preparing a butter enzyme solution: butter is mixed with water, sterilized, and then cooled to 45-55 DEG C, and then activated compound lipase is added, and enzyme hydrolysis is carried out for 4-6 hours, and then the oil phase is obtained after enzyme inactivation and separation;

[0033] S2, preparing a reconstituted milk enzyme solution: whole milk powder, whey protein, and whipped cream are mixed with water, sterilized, and then cooled to 45-50 DEG C, and then compound enzyme solution is added, and enzyme hydrolysis is carried out for 4-6 hours, and then homogenization and cooling are carried out after enzyme inactivation;

[0034] S3, mixing and emulsifying: the butter enzyme solution and the reconstituted milk enzyme solution are mixed in proportion, and whey protein powder, malt dextrin, compound modified starch, high-temperature protective agent, and flavor enhancer are added, and water bath stirring and emulsification are carried out;

[0035] S4, homogenization and sterilization: homogenization is carried out at 22-25 MPa, and sterilization is carried out at 95 DEG C for 10-15 minutes;

[0036] S5, spray drying: the inlet air temperature is 175-185 DEG C, the outlet air temperature is 80-90 DEG C, the sample flow rate is 300-350 ml / h, and the needle frequency is once every 8-10 seconds.

[0037] Further, the preparation method has the following steps: the water bath stirring in step S3 is divided into two stages, the enzyme solution mixing stage is stirring at 80 DEG C for 20 minutes, and the wall material mixing stage is stirring at 75 DEG C for 40 minutes.

[0038] The application further discloses application of the high-temperature resistant natural milk flavor essence, and has the characteristics that the application is used in baked foods, UHT dairy products, high-temperature sterilized beverages or candies, and the adding amount is 0.1-0.5%.

[0039] Further, the application has the following characteristics: after the essence is baked at 180 DEG C for 10 minutes, the milk aroma retention rate is greater than or equal to 85%, no odor is generated, and the sensory score is greater than or equal to 4 points (5 points system); the moisture content of the spray-dried essence product is less than or equal to 5%, the particle size distribution D50 is 50-100 mu m, and the solubility is greater than or equal to 95%.

[0040] Compared with the prior art, the application has the following outstanding beneficial effects:

[0041] 1. Natural and superior flavor: Using butter and reconstituted milk as substrates, a rich, harmonious and layered natural milk flavor ingredient is generated through a complex enzymatic hydrolysis technology with multiple specific lipases and proteases, avoiding the unnaturalness of chemical synthetic flavors and the weakness of natural extract aroma, with pure and natural flavor.

[0042] 2. Excellent high-temperature resistance: Innovative use of esterified and cross-linked starch modified by octenyl succinic anhydride and sodium trimetaphosphate, combined with whey protein and maltodextrin to form an efficient embedding wall material system, supplemented by a high-temperature protective agent composed of gum arabic and β-cyclodextrin, through multiple synergistic effects, an effective protective barrier is formed for volatile flavor substances at high temperatures, greatly reducing the loss of aroma and thermal degradation during processing.

[0043] 3. Good application adaptability: The final product is a powder with good flowability, low moisture content and high solubility, making it easy to disperse in various food systems. It not only performs well in normal and low-temperature foods, but also in high-temperature applications such as baking and sterilization, expanding the application range of natural milk flavor.

[0044] 4. Stability and industrial value: The production process is stable and controllable, with good batch consistency. By optimizing the spray drying parameters, the feasibility and economy of production are ensured, with high potential for industrial production. BRIEF DESCRIPTION OF DRAWINGS

[0045] Figure 1 Sensory evaluation score of aroma intensity (0-5) in high-temperature resistance comparison test;

[0046] Figure 2 Sensory evaluation score of milk flavor purity (0-5) in high-temperature resistance comparison test;

[0047] Figure 3 Sensory evaluation score of off-flavor (0-5) in high-temperature resistance comparison test;

[0048] Figure 4 Sensory evaluation score of aroma retention rate (%) in high-temperature resistance comparison test. DETAILED DESCRIPTION

[0049] Table 1: Main raw materials

[0050]

[0051]

[0052] Table 2: Source of enzyme preparation

[0053]

[0054] Table 3 Raw materials required for preparing the complex modified starch

[0055]

[0056] Example 1

[0057] A high-temperature resistant natural milk flavoring essence, made of the following components in parts by weight:

[0058] Butter enzyme hydrolysate: 10 parts

[0059] Reconstituted milk enzyme hydrolysate: 150 parts

[0060] Whey protein powder: 20 parts

[0061] Maltodextrin: 130 parts

[0062] Complex modified starch: 100 parts

[0063] High-temperature protective agent: 5 parts (of which gum arabic 2.5 parts, β-cyclodextrin 2.5 parts)

[0064] Natural milk flavor enhancer: 0.5 parts (fermented whey concentrate is used)

[0065] Deionized water: 500 parts

[0066] The preparation method thereof comprises the following steps:

[0067] S1. Preparation of butter enzyme hydrolysate:

[0068] (1) Weigh 100 parts of butter and 20 parts of deionized water into a reaction tank and mix well.

[0069] (2) Sterilization: heat the mixture to 95°C and maintain at this temperature for 10 minutes.

[0070] (3) Cooling and enzyme hydrolysis: cool the mixture to 55°C. Weigh 0.1 parts of lipase (mixed by AMANO AY30SD and AMANO A12 in a ratio of 1:1 of enzyme activity units), add to 5 parts of phosphate buffer (pH 7.0) at a temperature of 55°C, and gently stir for 5 minutes for activation. Add the activated enzyme solution to the butter mixture and continue to stir at a constant temperature of 55°C for 4 hours.

[0071] (4) Enzyme inactivation: heat the enzyme hydrolysate to 90°C and maintain for 10 minutes to terminate the reaction.

[0072] (5) Liquid separation and collection: transfer the enzyme-inactivated reaction liquid to a separatory funnel, stand for 10 minutes, and after it is layered, separate and collect the upper oil phase to obtain the butter enzyme hydrolysate, and cool to below 50°C for standby.

[0073] S2. Preparation of reconstituted milk enzymatic solution:

[0074] (1) Take 80 parts of full-fat milk powder, 15 parts of whey protein powder, 5 parts of whipping cream and 400 parts of deionized water in a material mixing tank.

[0075] (2) Material mixing and sterilization: Under the condition of 70℃ water bath, stirring for 40 minutes to make it fully dissolved and dispersed, then heated to 95℃, maintained for 10 minutes for sterilization.

[0076] (3) Cooling and enzymolysis: Cool the mixture to 50℃. Take 0.8 parts of complex enzyme (mixed by neutral protease and lipase AMANO MER in a ratio of 3:1 enzyme activity units), add to 10 parts of deionized water with a temperature of 50℃, and gently stir for 5 minutes. Add this activated enzyme solution to the reconstituted milk mixture and continue to stir at 50℃ for 6 hours.

[0077] (4) Enzyme inactivation and homogenization: Heat the enzymatic solution to 95℃ and maintain for 10 minutes to terminate enzyme activity. Then homogenize under a pressure of 18-20 MPa.

[0078] (5) Cooling: Cool the homogenized enzymatic solution to below 30℃ to obtain a reconstituted milk enzymatic solution, ready for use.

[0079] S3. Mixing and emulsification:

[0080] (1) Take 10 parts of butter enzymatic solution prepared in S1 and 150 parts of reconstituted milk enzymatic solution prepared in S2 according to the above proportions, mix well, and stir in a 80℃ water bath for 20 minutes.

[0081] (2) Take 20 parts of whey protein powder, 130 parts of malt dextrin, 100 parts of complex modified starch and 200 parts of deionized water, mix them in a 75℃ water bath for 40 minutes to make them fully dissolved and dispersed, to obtain a wall material mixture.

[0082] (3) Slowly pour the wall material mixture obtained in step (2) into the enzymatic solution mixture of step (1) under continuous and rapid stirring, and continue to stir rapidly for 5 minutes after adding to make it fully emulsified and mixed.

[0083] S4. Homogenization and sterilization:

[0084] Homogenize the mixed emulsion obtained in S3 under a pressure of 25 MPa. Then heat the homogenized material to 95℃ for 10 minutes for sterilization.

[0085] S5. Spray drying:

[0086] The sterilized feed liquid is subjected to spray drying. The process parameters are: inlet air temperature 185°C, outlet air temperature 80°C, sample flow rate 300 ml / h, and needle frequency once every 10 seconds. The powder discharged from the bottom of the drying tower is collected, and the high-temperature-resistant natural milk flavor essence product is obtained.

[0087] The preparation method of the composite modified starch is as follows:

[0088] (1) The cassava native starch is prepared into a 35% (w / w) starch slurry, and 5% of sodium chloride based on the dry mass of the starch is added as a coagulation inhibitor, and the mixture is stirred uniformly.

[0089] (2) The pH of the system is adjusted to 9.0 with 3% sodium hydroxide solution, and 2% octenyl succinic anhydride based on the dry mass of the starch is slowly added under continuous stirring. During the reaction, the pH is maintained at 9.0±0.1 by adding alkali solution dropwise, and the reaction temperature is controlled at 35°C, and the reaction time is 4 hours.

[0090] (3) After the esterification is completed, stirring is maintained, 0.5% sodium trimetaphosphate based on the dry mass of the starch is added, the pH is adjusted and maintained at 11.5±0.1 with sodium hydroxide solution, and the temperature is raised to 50°C for crosslinking reaction for 1 hour.

[0091] (4) After the reaction is completed, the pH is adjusted to 6.5 with dilute hydrochloric acid, and the composite modified starch is obtained after filtration, washing with deionized water for 3 times, drying, and crushing to pass through a 100-mesh sieve.

[0092] Example 2

[0093] A high-temperature-resistant natural milk flavor essence is prepared from the following components in parts by weight:

[0094] Butter enzyme hydrolysate: 20 parts

[0095] Reconstituted milk enzyme hydrolysate: 120 parts

[0096] Whey protein powder: 25 parts

[0097] Malt dextrin: 120 parts

[0098] Composite modified starch: 110 parts

[0099] High-temperature protection agent: 3 parts (including 1.8 parts of gum arabic and 1.2 parts of β-cyclodextrin)

[0100] Natural milk flavor enhancer: 1 part (using natural milk ester extract)

[0101] Deionized water: 420 parts

[0102] The preparation method is basically the same as that of Example 1, except that:

[0103] The preparation method is basically the same as that of Example 1, except that:S1 step: lipase using AMANO MER and AMANO A12 compound according to the ratio of enzyme activity units 1:2, the total amount of 0.15% of the butter. Enzymolysis temperature is 50℃, enzymolysis time is 5 hours.

[0104] S2 step: enzymolysis temperature is 48℃, enzymolysis time is 5 hours.

[0105] S5 step: spray drying parameter adjustment: inlet air temperature 180℃, outlet air temperature 85℃, sample flow rate 340ml / h, needle frequency every 8 seconds.

[0106] Preparation of composite modified starch: the addition amount of octenyl succinic anhydride in step (2) is 3% of the dry basis mass of starch, and the reaction time is 5 hours; the addition amount of sodium trimetaphosphate in step (3) is 0.8% of the dry basis mass of starch, and the crosslinking reaction time is 1.5 hours.

[0107] Example 3

[0108] A high-temperature-resistant natural milk flavor essence is prepared from the following components by weight fraction:

[0109] Butter enzyme solution: 30 parts

[0110] Reconstituted milk enzyme solution: 80 parts

[0111] Whey protein powder: 30 parts

[0112] Maltodextrin: 100 parts

[0113] Composite modified starch: 120 parts

[0114] High-temperature protective agent: 1 part (of which gum arabic 0.67 parts, β-cyclodextrin 0.33 parts)

[0115] Natural milk flavor enhancer: 2 parts (using fermented whey concentrate)

[0116] Deionized water: 300 parts

[0117] Its preparation method is basically the same as that of example 1, the difference is:

[0118] S1 step: lipase using AMANO AY30SD, AMANO MER and AMANO A12 compound according to the ratio of enzyme activity units 1:1:2, the total amount of 0.5% of the butter. Enzymolysis temperature is 45℃, enzymolysis time is 6 hours.

[0119] S5 step: spray drying parameter adjustment: inlet air temperature 175℃, outlet air temperature 90℃, sample flow rate 350ml / h, needle frequency every 8 seconds.

[0120] Complex modified starch preparation: the addition amount of octenyl succinic anhydride in step (2) is 4% of the dry mass of the starch, the reaction temperature is 30°C, and the reaction time is 6 hours; the addition amount of sodium trimetaphosphate in step (3) is 1.2% of the dry mass of the starch, the reaction temperature is 45°C, and the crosslinking reaction time is 2 hours.

[0121] Comparative Example 1

[0122] A milk flavor, the components and preparation method of which are exactly the same as those of Example 2, the only difference being that the 110 parts of the complex modified starch are replaced by an equal amount of ordinary cassava native starch.

[0123] Comparative Example 2

[0124] A milk flavor, the components and preparation method of which are exactly the same as those of Example 2, the only difference being that in step S1, only AMANO A12 is used as the lipase, the enzyme addition amount is 0.15% of the butter, and the enzyme hydrolysis conditions are the same as those of Example 2.

[0125] Comparative Example 3

[0126] A milk flavor, the components and preparation method of which are exactly the same as those of Example 2, the only difference being that the high-temperature protective agent (i.e., gum arabic and β-cyclodextrin) is not added in the formula.

[0127] Comparative Example 4

[0128] A milk flavor, the components and preparation method of which are exactly the same as those of Example 2, the only difference being that the enzyme hydrolysis step is omitted, and the raw materials are directly used. That is:

[0129] In step S1, no enzyme hydrolysis reaction is performed. After sterilization of the mixture of butter and water at 95°C and cooling to 50°C, no lipase is added, and the mixture is directly stirred at this temperature for 5 hours, followed by enzyme inactivation and liquid separation. The obtained product is a heat-treated butter, rather than a butter enzyme hydrolysate.

[0130] In step S2, no enzyme hydrolysis reaction is performed. After sterilization of the reconstituted milk raw material at 95°C and cooling to 48°C, no complex enzyme is added, and the mixture is directly stirred at this temperature for 5 hours, followed by sterilization and homogenization. The obtained product is a heat-treated reconstituted milk, rather than a reconstituted milk enzyme hydrolysate.

[0131] Design purpose: This comparative example is used to prove the core role of the enzyme hydrolysis process in the present application. It explores whether the same flavor effect and heat resistance can be achieved by physical mixing and heat treatment alone, without the specific flavor substances (such as free fatty acids and esters) produced by enzyme hydrolysis.

[0132] Comparative Example 5

[0133] A milk flavoring, the components and preparation method of which are exactly the same as those of Example 2, the only difference being that a conventional spray-drying wall material system is used. Namely:

[0134] The specific wall material combination of "whey protein powder + malt dextrin + complex modified starch" in the formula is replaced with an equivalent amount of the most commonly used conventional wall material system for spray-drying milk fat powder in the food industry: "malt dextrin 150 parts + gum arabic 35 parts".

[0135] Design purpose: This comparative example is used to prove the superiority of the specific wall material combination (whey protein / malt dextrin / complex modified starch) in the present application compared to conventional technical means in the art. It aims to show that not any wall material can effectively cooperate with the enzymatic solution of the present application and provide excellent high-temperature resistance protection effect, highlighting the uniqueness and unpredictability of the wall material formula of the present application.

[0136] Test Example 1

[0137] High-temperature resistance performance comparison test

[0138] Purpose: To verify the aroma retention ability and flavor stability of the natural milk flavoring of the present application after high-temperature treatment, and to investigate its core high-temperature resistance characteristics.

[0139] Method:

[0140] Sample preparation: Take 1.0 g of the flavoring powder prepared in Examples 1-3 and Comparative Examples 1-5, respectively, and mix them evenly with 100 g of tasteless plant fat powder (carrier) in a sealed bag to prepare a test base containing 1% of the flavoring.

[0141] High-temperature treatment: Accurately weigh 5.0 g of the above test base and spread it on a petri dish, then place it in a preheated to 180°C air-drying oven for 10 minutes.

[0142] Sensory evaluation: After cooling to room temperature, 10 trained sensory evaluators perform blind evaluation. The evaluators score the high-temperature treated samples on aroma intensity, milk flavor purity, and off-flavors (burnt taste, rancid taste, etc.) (0-5 point system, 5 points being the best). At the same time, the same sample without high-temperature treatment is used as a reference (100%), and the aroma retention rate (%) is estimated.

[0143] Data processing: Calculate the average of each score and the average of the aroma retention rate.

[0144] The results are shown in Table 4 and Figures 1-4 :

[0145] Table 4: Sensory evaluation of high-temperature resistance performance and aroma retention rate

[0146] Group Intensity of aroma (0-5) Degree of purity of milk aroma (0-5) Odor (0-5) Retention rate of aroma (%) Example 1 4.3±0.4 4.2±0.3 4.8 (no odor) 87.5 Example 2 4.7±0.3 4.6±0.4 4.9 (no odor) 92.0 Example 3 4.5±0.5 4.4±0.5 4.7 (no odor) 89.5 Comparative Example 1 2.8±0.6 2.5±0.7 2.0 (distinct burnt taste) 64.0 Comparative Example 2 3.2±0.5 2.9±0.6 2.5 (slight greasy off-note) 74.5 Comparative Example 3 3.7±0.4 3.5±0.5 3.8 (slightly irritating) 79.0 Comparative Example 4 2.0±0.7 1.8±0.8 3.0 (boiled taste, weak aroma) 48.5 Comparative Example 5 3.5±0.6 3.2±0.7 3.5 (thin aroma) 71.5

[0147] Conclusion: The aroma retention rate of the product of each embodiment of the present application is higher than 85% after high temperature treatment of 180℃ / 10min, and the rich milk aroma and pure flavor can be maintained without odor. The comparative example 1 (ordinary starch) has the worst heat resistance, which proves the key role of the composite modified starch in embedding and protecting flavor substances; the comparative example 4 (without enzyme hydrolysis) has the weakest aroma intensity, which proves that the enzyme hydrolysis process is the basis for producing core flavor substances; the comparative examples 2 (single enzyme) and 3 (without protective agent) have the next effect, which proves the important contribution of composite enzyme hydrolysis and high temperature protective agent. The effects of each comparative example are significantly worse than the embodiments, which proves the necessity of the synergistic effect of the formula system of the present application.

[0148] Test Example 2

[0149] Conventional application performance test

[0150] Purpose: To determine the basic physical property indexes of the fragrance finished product of the present application and evaluate its convenience in actual application.

[0151] Method:

[0152] Moisture content: determined according to the direct drying method in GB 5009.3-2016 "National Food Safety Standard Determination of Moisture in Food".

[0153] Solubility: 1.0g of sample (accurate to 0.0001g) was weighed in a beaker, 99g of 50℃ distilled water was added, and it was stirred at 300rpm for 5 minutes, and the dissolution was observed and recorded. After centrifugation (3000rpm, 5min), the supernatant was poured out, and the remaining insoluble material was dried at 105℃ to constant weight, and the solubility (%) was calculated.

[0154] Flowability (angle of repose): using an angle of repose tester, the powder was allowed to flow freely through the funnel to the plane, and the bottom angle of the conical pile was measured, and the average value was taken for 3 times. The smaller the angle, the better the flowability.

[0155] The results are shown in Table 5:

[0156] Table 5: Basic physical property indexes of fragrance

[0157] Group Moisture content (%) Solubility (%) Angle of repose (°) Example 1 4.2 96.5 36.5 Example 2 3.8 98.2 34.0 Example 3 4.5 95.8 37.8 Comparative Example 1 4.8 88.3 42.5 Comparative Example 5 4.1 92.5 39.2

[0158] Conclusion: The moisture content of the product of the present application is low (<5%), which is beneficial for preservation; the solubility is high (>95%), which is easy to disperse in various aqueous systems; the angle of repose is small, indicating that the powder has good flowability, which is convenient for metering, conveying and packaging in industrialized production. The solubility and flowability of the comparative example 1 (ordinary starch) are poor because it is not modified. The solubility of the comparative example 5 (conventional wall material) is also not as good as the specific wall material combination of the present application.

[0159] Test Example 3

[0160] Flavor persistence test in high temperature application scenario (take baking as an example)

[0161] Objective: To simulate baking application, evaluate the long-acting temperature resistance and flavor contribution of the flavor in complex food matrix.

[0162] Method:

[0163] Sample preparation: butter-free cookies were made with the flavor of Example 2 and Comparative Examples 1-5. Base formula: 150 parts of low-gluten flour, 45 parts of sugar, 100 parts of corn oil, 55 parts of egg, 2 parts of salt, 0.3 parts of flavor. All groups were consistent in process: raw materials mixing→ molding→ baking at 180℃ for 10 minutes.

[0164] Sensory evaluation: after baking, the cookies were cooled and evaluated by 10 evaluators. Evaluation was carried out at 1 day (initial) and 7 days (terminal) after baking, mainly to investigate milk flavor intensity and flavor harmony (0-5 points).

[0165] Flavor attenuation calculation: the retention rate of flavor score at 7 days relative to 1 day was calculated.

[0166] The results are shown in Table 6:

[0167] Table 6: Flavor evaluation of cookie baking application

[0168]

[0169] Conclusion: cookies with the flavor of the present application (Example 2) not only exhibit rich milk flavor immediately after baking, but also have high retention rate of flavor intensity and harmony (>93%) after 7 days of storage, proving excellent flavor persistence. The initial flavor of the comparative sample is weak, and it decays severely over time. This indicates that the flavor of the present application not only tolerates instantaneous high temperature, but also provides stable flavor support in the final product.

[0170] Test Example 4

[0171] Thermal stability accelerated test (high temperature storage)

[0172] Objective: To evaluate the stability of the flavor powder itself during storage by accelerated test.

[0173] Method:

[0174] The flavor powders of Example 2 and Comparative Examples 1, 3, 5 were divided into open petri dishes with a thickness of less than 5 mm.

[0175] They were placed in a constant temperature incubator at 50℃ to accelerate oxidation and flavor change.

[0176] The peroxide value (POV) was determined according to GB 5009.227-2016 at day 0, day 7, day 14.

[0177] Meanwhile, the sensory panelists evaluated whether the oil oxidation rancid taste appeared.

[0178] The results are shown in Table 7:

[0179] Table 7: Change of peroxide value (POV) after accelerated storage at 50℃ (unit: g / 100g)

[0180]

[0181]

[0182] Conclusion: After 14 days of accelerated storage at 50℃, the peroxide value of the fragrance of Example 2 of the present application increased slowly, and no unpleasant rancid taste appeared, showing excellent oxidative stability. The oxidation of Comparative Example 1 (poor embedding effect of ordinary starch) was the most severe; the stability of Comparative Example 3 (without high-temperature protective agent) and Comparative Example 5 (conventional wall material) was also significantly worse than that of Example 2. This proves the synergistic effect of the composite modified starch and the high-temperature protective agent in the present application, which can effectively delay the oxidation of oil components and prolong the shelf life of the product.

[0183] Test Example 5

[0184] Sensory evaluation comprehensive application test

[0185] Purpose: To comprehensively evaluate the overall flavor effect of the fragrance of the present application in representative end products.

[0186] Method:

[0187] Application product: Select UHT pure milk and crisp biscuits as two application carriers.

[0188] Sample preparation:

[0189] UHT milk: Add 0.1% of the fragrances of Example 2, Comparative Example 1 and Comparative Example 4 respectively in the odorless UHT milk and stir evenly.

[0190] Crisp biscuits: Make biscuits according to the method of Test Example 3, and use the fragrances of Example 2 and Comparative Example 1.

[0191] Evaluation: The samples were evaluated by a sensory evaluation panel of 20 people. A 9-point preference score (1 = very dislike, 9 = very like) was used, and the evaluation indicators included aroma intensity, flavor authenticity (like natural milk), mouthfeel harmony and overall acceptance.

[0192] The results are shown in Table 8:

[0193] Table 8: Sensory preference score of end products (n = 20)

[0194] Application product Evaluation index Example 2 Comparative Example 1 Comparative Example 4 UHT milk Intensity of aroma (UHT milk) 8.2 6.5 5.0 UHT milk Flavor authenticity 8.5 7.0 5.5 UHT milk Overall acceptability 8.4 6.8 5.3 UHT milk (supplement) Intensity of aroma (possibly different test conditions, etc.) 8.0 6.0 - Shortbread Flavor authenticity 8.3 6.3 - Shortbread Overall acceptability 8.5 6.5 -

[0195] Conclusion: In both UHT milk and biscuit applications, the products added with the invented essence (Example 2) achieved significantly higher scores in aroma intensity, flavor authenticity and overall acceptance. The evaluators considered it to have rich and natural milk aroma, and good integration with the product matrix. The comparative products were considered to have insufficient aroma, artificial or distorted flavor after high temperature. This comprehensively proves the excellent effect and broad application potential of the invented natural milk flavor essence in real application scenarios.

[0196] Test example summary:

[0197] The present application verifies the comprehensive performance of the natural milk flavor essence through five test examples. Test example 1 shows that the aroma retention rate of the example product after 10 minutes of high temperature treatment at 180℃ is higher than 85%, and the sensory score is ≥4, which is significantly better than each comparative example, proving its excellent high temperature resistance. Test example 2 shows that the product has a water content of ≤5%, a solubility of ≥95%, and a rest angle of ≤38°, and has good application adaptability. Test example 3 simulates baking applications, and the flavor retention rate of Example 2 in cookies after 7 days is still 93.5%, showing excellent flavor persistence. Test example 4 confirms that the peroxide value of Example 2 grows slowly and has no rancid taste through the 50℃ accelerated storage test, and the antioxidant stability is outstanding. Test example 5 has significantly higher sensory preference scores in UHT milk and biscuits than the comparative examples, further proving its excellent performance in end products. In summary, through the synergistic effect of complex enzymatic hydrolysis, specific wall material and high temperature protection agent, the essence effectively solves the technical problems of natural milk flavor essence being prone to loss of aroma and deterioration in high temperature processing.

[0198] The above shows and describes the basic principles, main features and advantages of the present application. Those skilled in the art should understand that the above examples do not limit the present application in any form, and any technical solution obtained by equivalent substitution or equivalent transformation falls within the scope of the present application.

Claims

1. A heat-resistant natural milk flavoring, characterized in that, By weight, it includes the following components: Butter hydrolysate: 10–30 parts; Reconstituted milk hydrolysate: 80–150 portions; Whey protein powder: 20–30 servings; Maltodextrin: 100–130 parts; Composite modified starch: 100–120 parts; the composite modified starch is prepared by a composite modification process of octenyl succinic anhydride esterification and sodium trimetaphosphate crosslinking of native cassava starch; High-temperature protectant: 1–5 parts; Deionized water: 300–500 parts.

2. The high-temperature resistant natural milk flavoring according to claim 1, characterized in that: The preparation method of the composite modified starch includes the following steps: (1) Prepare a slurry of 35-40% cassava starch, add sodium chloride at 3-5% of the dry weight of starch as a coagulant, and stir evenly. (2) Adjust the pH of the system to 8.5-9.0 with 2-4% sodium hydroxide solution, and slowly add 2-4% of octenyl succinic anhydride by dry starch under continuous stirring. During the reaction, maintain the pH at 8.5-9.0 with alkaline solution, control the reaction temperature at 30-35℃, and the reaction time is 4-6 hours. (3) After esterification is completed, keep stirring, add sodium trimephosphate at 0.5-1.2% of the dry weight of starch, adjust and maintain the pH at 11.0-11.5 with alkaline solution, raise the temperature to 45-50℃ and carry out cross-linking reaction for 1-2 hours. (4) After the reaction is completed, the pH is adjusted to 5.5-6.5 with hydrochloric acid to terminate the reaction. After washing, filtering, drying and pulverizing, the composite modified starch is obtained.

3. The high-temperature resistant natural milk flavoring according to claim 1, characterized in that: The butter hydrolysate is obtained by enzymatic hydrolysis of at least two lipases. The lipases are selected from two or three of the following: a 1,3-position specific lipase from Rhizomucormiehei, a non-specific lipase from Candida rugosa, and a lipase from Aspergillus niger. The total amount of enzymes added is 0.1–0.5% of the butter, the hydrolysis temperature is 45–55°C, and the hydrolysis time is 4–6 hours.

4. The high-temperature resistant natural milk flavoring according to claim 3, characterized in that: In the butter hydrolysate, the enzyme activity ratio of the 1,3-position specific lipase from *Mucor milchus*, the non-specific lipase from *Candida albicans*, and the lipase from *Aspergillus niger* is (1–2):(1–2):(1–3).

5. The high-temperature resistant natural milk flavoring according to claim 1, characterized in that: The reconstituted milk hydrolysate is obtained by enzymatically hydrolyzing reconstituted milk with a complex protease and a lipase. The protease is trypsin or neutral protease, and the lipase is a 1,3-position specific lipase derived from Mucor miltiorrhiza or a non-specific lipase derived from Candida albicans. The hydrolysis temperature is 45–50℃, and the hydrolysis time is 4–6 hours.

6. The high-temperature resistant natural milk flavoring according to claim 1, characterized in that: The high-temperature protectant is a compound of gum arabic and β-cyclodextrin in a mass ratio of (1:1)–(2:1).

7. The method for preparing the high-temperature resistant natural milk flavoring according to any one of claims 1-6, characterized in that, Includes the following steps: S1 Preparation of butter hydrolysate: Mix butter with water, sterilize and cool to 45–55°C, add activated compound lipase, hydrolyze for 4–6 hours, inactivate enzyme and separate the oil phase. S2 Preparation of reconstituted milk hydrolysate: Mix whole milk powder, whey protein, light cream and water, sterilize and cool to 45-50℃, add compound enzyme solution, hydrolyze for 4-6 hours, inactivate enzyme, homogenize and cool. S3 Mixing and Emulsification: Mix the butter hydrolysate and the reconstituted milk hydrolysate in a certain proportion, add whey protein powder, maltodextrin, compound modified starch, high temperature protectant and flavor enhancer, and emulsify by stirring in a water bath; S4 Homogenization and sterilization: Homogenize at 22–25 MPa and sterilize at 95°C for 10–15 minutes; S5 spray drying: inlet air temperature 175–185℃, outlet air temperature 80–90℃, injection flow rate 300–350ml / h, needle flushing frequency once every 8–10 seconds.

8. The preparation method according to claim 7, characterized in that: The water bath stirring in step S3 is carried out in two stages: the enzymatic hydrolysate mixing stage is stirred at 80°C for 20 minutes, and the wall material mixing stage is stirred at 75°C for 40 minutes.

9. The application of the high-temperature resistant natural milk flavoring as described in any one of claims 1-6, characterized in that: It can be used in baked goods, UHT dairy products, high-temperature sterilized beverages or confectionery, with an addition amount of 0.1–0.5%.

10. The application according to claim 9, characterized in that: After being baked at 180℃ for 10 minutes, the flavoring retains ≥85% of its milky aroma, produces no off-odors, and has a sensory score of ≥4 points (out of 5). The spray-dried finished product of the flavoring has a moisture content of ≤5%, a particle size distribution D50 of 50–100 μm, and a solubility of ≥95%.

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