Patent Document: Method for Improving Quality Characteristics of Cheese Essence and Product

Patent Number: CN121942874A
Publication Date: January 28, 2026
Application Number: CN202610117673.8A
Current Status: Pending
Assignee/Applicant: Not explicitly identified in the document excerpt (the original filing would list the assignee).
Inventors: The inventors are not specifically named in this excerpt; the patent would typically list individual inventors associated with dairy product technology research.

Technical Field

The present invention relates to the technical field of dairy products, and specifically to a method for improving the quality characteristics of cheese essence and the product thereof.

Background of the Invention

Cheese essence is an important flavor substance widely applied in the fields of snack foods, seasonings, baked products, and the like. Natural cheese essence has seen increasingly high market demand due to its advantages of natural flavor, clean labels, and other desirable characteristics. Traditional natural cheese essence is mainly prepared through enzymatic hydrolysis and/or fermentation of cheese or similar base materials. The core principle involves utilizing protease and lipase to degrade proteins and fats into small-molecule flavor precursor substances such as peptides, amino acids, and free fatty acids, which then form the final characteristic flavor of the cheese through a series of pathways.

However, existing enzymatic hydrolysis methods for preparing cheese essence present several notable technical bottlenecks:

(1) Insufficient Flavor Intensity: Due to poor substrate accessibility, traditional methods may not adequately release potential flavor precursor materials, resulting in less-than-ideal flavor intensity, body, and layering in the final product.

(2) Flavor Harmony Issues: Conventional enzymatic hydrolysis processes may generate excessive bitter peptides or certain free fatty acids (such as butyric acid) with undesirable flavors, causing imbalance in the product's flavor profile and necessitating subsequent tedious debittering or flavor-modifying steps.

To overcome these problems, the prior art has attempted various physical pretreatment methods such as heating and homogenization. However, these methods have significant disadvantages:

• High-temperature treatment can alter protein structure but easily causes volatilization of flavor substances, premature generation of flavor reactions, or the development of cooked flavors, which destroys the fresh flavor characteristics of cheese.
• Excessive oxygen introduced during homogenization can cause fat oxidation and rancidity.

Ultra-High Pressure (UHP) Technology: As a non-thermal processing technology, UHP has been demonstrated to:

• Change the three-dimensional structure and gel characteristics of proteins
• Promote protein denaturation and extension
• Regulate the dispersion and distribution of fat globules

Thermal Shearing Technology: As a mechanical-thermal cooperative processing technology, thermal shearing can:

• Change the aggregation state and molecular conformation of proteins through the coupling effect of mechanical shearing force and thermal effects
• Achieve depolymerization and recombination of proteins
• Optimize particle size distribution and emulsion stability of fat globules

However, in the prior art, both technologies are generally used as pretreatment means for raw material systems alone, or as auxiliary treatment means for subsequent processes to improve rheological properties and texture uniformity of products, as reported in patents such as CN104286197A and CN111011533A. Currently, no research has been reported on combining ultra-high pressure technology with thermal shearing technology and cooperatively combining them with enzymatic hydrolysis technology to improve the quality of natural cheese essence.

Summary of the Invention

Technical Problem

The problem of poor flavor in conventional cheese essence preparation currently exists, necessitating a preparation method that enhances the flavor of cheese essence and improves its quality.

Technical Solution

Aiming at the deficiencies in the prior art, the present invention creatively combines ultra-high pressure treatment with enzymatic hydrolysis, thereby developing a novel process for preparing natural cheese essence with high efficiency and high quality.

The invention provides a method for improving quality characteristics of cheese essence, comprising the following steps:

S1. Performing hot shearing mixing on cheese curd, butter, water, and emulsifying salt to obtain a reaction matrix.

S2. Preprocessing the reaction matrix obtained in step S1 to obtain a pretreated reaction matrix.

S3. Adding protease to the pretreated reaction matrix obtained in step S2 for enzymatic hydrolysis reaction, inactivating the enzyme after the reaction is completed, and then adding lipase for enzymatic hydrolysis reaction.

S4. After the enzymatic hydrolysis reaction is completed, performing enzyme deactivation through pasteurization to obtain the cheese essence.

Detailed Composition and Process Parameters

Step S1: Reaction Matrix Composition

The reaction matrix in step S1 comprises, by mass:

• Cheese curd: 50–54 parts
• Water: 31–35 parts
• Butter: 9–13 parts
• Emulsifying salt: 0.5–3 parts

Emulsifying Salt Selection: Sodium citrate and/or sodium tripolyphosphate.

Cheese Curd Details: The cheese curd is enzymatic cheese curd, obtained after 15–30 days of curd formation.

Thermal Shearing Conditions:

• Temperature: 50–70°C
• Stirring speed: 1500–2000 r/min
• Time: 15–45 minutes

Step S2: Preprocessing (Ultra-High Pressure Treatment)

The pretreatment in step S2 is ultra-high pressure treatment, conducted at:

• Temperature: 20–25°C
• Pressure: 200–600 MPa
• Time: 10–30 minutes
• Conducting medium: Water

Step S3: Enzymatic Hydrolysis

Proteases Used:

• Flavourzyme: Enzyme activity 800–1200 LAPU/g; addition amount: 0.1–0.3% of the mass of cheese curd and butter in the reaction matrix
• Neutral Protease: Enzyme activity 0.5–1 AU-A/g; addition amount: 0.3–0.5% of the mass of cheese curd and butter in the reaction matrix

Lipase Used:

• Lipase F3G: Enzyme activity 25,000–35,000 U/g; addition amount: 0.2–0.6% of the mass of cheese curd and butter in the reaction matrix

Enzymatic Hydrolysis Conditions:

• Temperature: 40–55°C
• Time: 10–20 hours
• pH: 5.5–7.5

Step S4: Pasteurization

Pasteurization Conditions:

• Temperature: 85–95°C
• Time: 5–15 minutes

Cheese Essence Product

The invention provides a cheese essence prepared by the above method, which is applicable in the field of foods.

Advantages of the Present Invention

1. Enhanced Flavor Intensity and Richness:

• Ultra-high pressure pretreatment effectively destroys the microstructure of cheese curd
• Fully exposes protein and fat embedded in the cheese curd
• Greatly increases the contact area between enzyme and substrate
• Creates extremely favorable conditions for subsequent enzymatic hydrolysis
• Promotes more thorough hydrolysis reactions
• Generates more small-molecule flavor precursor substances such as amino acids and free fatty acids
• Significantly improves flavor intensity and richness of the final essence

2. Improved Flavor Harmony and Reduced Bitterness:

• Ultra-high pressure pretreatment changes the protein hydrolysis pathway
• Reduces the generation of bitter peptides
• Avoids pungent odors caused by excessive short-chain fatty acids
• Results in a more harmonious and mellow product flavor
• Significantly reduces bitter taste

3. Preservation of Fresh Flavor and Nutrients:

• UHP is a non-thermal processing technology
• Avoids high-temperature damage to thermosensitive flavor substances
• Better preserves inherent fresh flavor and nutritional ingredients of raw materials
• Aligns with the consumer trend toward "clean labels"

4. Enhanced Pleasant Flavor Characteristics:

• Characteristic flavors such as frankincense, cream flavor, and butter flavor are more prominent
• Eliminates the monotonous flavor problem of traditional process products
• Offers wider market prospects

Detailed Raw Material Sources and Testing Methods

Raw Material Sources

Testing Methods

Sensory Evaluation:

• Panel: 20 experienced sensory evaluators (10 men, 10 women)
• Scoring system: 10-point scale (0–10)
• Results: Average of 20 evaluator scores
• Repetition: 3 times per experiment

Free Amino Acid Determination:

1. Sample pretreatment: Mix with 10% (w/v) trichloroacetic acid solution at 1:1 (v/v), sonicate for 30 minutes, allow to stand overnight at 4°C, centrifuge at 4°C and 10,000×g for 30 minutes, filter supernatant through 0.22 μm filter membrane
2. Analysis: Agilent 1100 HPLC system with Hypersil ODS C18 column (4.6 mm × 105 mm, 5 μm)
3. Conditions: Column temperature 40°C, detection wavelength 338 nm (proline 262 nm)
4. Mobile phase: (A) 27.6 mmol/L sodium acetate-triethylamine-tetrahydrofuran (500:0.11:2.5, v/v/v, pH 7.2); (B) 80.9 mmol/L sodium acetate-methanol-acetonitrile (1:2:2, v/v/v, pH 7.2)
5. Flow rate: 1.0 mL/min, gradient elution
6. Quantification: External standard method

Free Fatty Acid Determination:

1. Extraction: Accurately weigh 10 g sample, add chloroform and methanol solution, vortex, centrifuge, collect supernatant, dry by rotary evaporator to obtain crude fat
2. Purification: Thin layer chromatography with n-hexane-diethyl ether-acid (70:29:1, v/v/v) as developing agent
3. Methyl esterification: Mix purified fatty acid with internal standard methyl nonadecanoate, n-hexane, methanol, and KOH-methanol solution (0.5 mol/L), react at 55°C for 20 minutes
4. Extraction: Extract fatty acid methyl ester with n-hexane, filter through 0.22 μm filter membrane
5. GC Analysis: TR-FAME capillary column (60 m × 0.25 mm × 0.2 μm), carrier gas constant flow rate 1 mL/min, split ratio 1:100
6. Temperatures: Inlet 230°C, detector 250°C
7. Column temperature program: Initial 60°C for 3 minutes, increase to 175°C at 5°C/min and hold for 15 minutes, then increase to 220°C at 2°C/min and hold for 10 minutes
8. Identification: Comparison to standard retention times; quantification by internal standard

Volatile Flavor Substance Determination:

1. Method: Solid Phase Microextraction (SPME) combined with GC-MS
2. Sample preparation: Accurately weigh 4.0 g sample, place in 15 mL sample bottle, add 5 μL of 1,2-dichlorobenzyl alcohol solution (1.306 mg/mL) as internal standard
3. Extraction: 50/30 μm DVB/CAR/PDMS extraction head, headspace adsorption at 60°C for 30 minutes
4. Desorption: Thermal desorption at 250°C inlet for 5 minutes
5. GC Conditions: HP-Innowax capillary column (60 m × 0.25 mm × 0.25 μm), helium carrier gas at 1.0 mL/min, splitless injection
6. Column temperature program: Initial 40°C for 2 minutes, increase to 120°C at 10°C/min, increase to 150°C at 2.5°C/min and hold for 5 minutes, final increase to 230°C at 10°C/min and hold for 10 minutes
7. MS Conditions: Ionization energy 70 eV, full scan range m/z 30–450
8. Identification: Comparison with standards

Examples

Example 1 (200 MPa Ultra-High Pressure)

S1: Fill 52.57% cheese curd, 11.82% butter, 33.64% water, and 1.97% emulsifying salt into a container. Perform hot shearing at 60°C, 1800 r/min for 30 minutes until the mixture is fine and uniform, forming the reaction matrix.

S2: Fill the reaction matrix into a PET food vacuum fresh-keeping bag, vacuum seal, place in ultra-high pressure equipment using water as the conducting medium. Treat at an initial temperature of 25°C under 200 MPa pressure for 20 minutes.

S3: Cool the treated raw material matrix to room temperature. Add flavourzyme at 0.1% of the mass of solids (cheese curd and butter) and neutral protease at 0.3% of the mass of solids. Stir at 45°C, 1500 r/min for 18 hours. Inactivate enzymes by stirring at 90°C, 1500 r/min for 10 minutes.

S4: Cool the proteolytic reaction matrix to room temperature. Add lipase F3G at 0.4% of the solid mass. Stir at 45°C, 1500 r/min for 18 hours. Inactivate enzymes by stirring at 90°C for 10 minutes. Cool to room temperature to obtain the natural cheese essence.

Example 2 (400 MPa Ultra-High Pressure)

S1: Same as Example 1.

S2: Ultra-high pressure treatment at 400 MPa for 20 minutes.

S3: Same enzymatic hydrolysis as Example 1.

S4: Same lipase treatment as Example 1.

Example 3 (600 MPa Ultra-High Pressure)

S1: Same as Example 1.

S2: Ultra-high pressure treatment at 600 MPa for 20 minutes.

S3: Same enzymatic hydrolysis as Example 1.

S4: Same lipase treatment as Example 1.

Comparative Examples

Comparative Example 1 (No Ultra-High Pressure Treatment)

S1: Same formulation as Example 1. Heat, emulsify, and stir at 60°C, 1800 r/min for 30 minutes until fine and uniform.

S2: Cool to room temperature. Add flavourzyme at 0.1% and neutral protease at 0.3% of the solids mass. Stir at 45°C, 1500 r/min for 18 hours. Inactivate enzymes at 90°C, 1500 r/min for 10 minutes.

S3: Cool to room temperature. Add lipase F3G at 0.4% of the solid mass. Stir at 45°C, 1500 r/min for 18 hours. Inactivate enzymes at 90°C for 10 minutes. Cool to room temperature.

Comparative Example 2 (Ultra-High Pressure Treatment After Enzymolysis)

S1: Same formulation as Example 1. Heat, emulsify, and stir at 60°C, 1800 r/min for 30 minutes until fine and uniform.

S2: Cool to room temperature. Add flavourzyme at 0.1% and neutral protease at 0.3% of the solids mass. Stir at 45°C, 1500 r/min for 18 hours. Inactivate enzymes at 90°C, 1500 r/min for 10 minutes.

S3: Cool to room temperature. Add lipase F3G at 0.4% of the reaction matrix mass. Stir at 45°C, 1500 r/min for 18 hours. Inactivate enzymes at 90°C for 10 minutes. Cool to room temperature.

S4: Fill the post-enzymolysis raw material matrix into a PET food vacuum fresh-keeping bag, vacuum seal, place in ultra-high pressure equipment with water as the conducting medium. Treat at 25°C under 200 MPa pressure for 20 minutes.

Comparative Example 3 (Conventional Heating Stirring, No Ultra-High Pressure)

S1: Same formulation as Example 1. Heat and stir at 60°C, 500 r/min for 30 minutes until fine and uniform.

S2: Cool to room temperature. Add flavourzyme at 0.1% and neutral protease at 0.3% of the solids mass. Stir at 45°C, 1500 r/min for 18 hours. Inactivate enzymes at 90°C, 1500 r/min for 10 minutes.

S3: Cool to room temperature. Add lipase F3G at 0.4% of the solid mass. Stir at 45°C, 1500 r/min for 18 hours. Inactivate enzymes at 90°C for 10 minutes. Cool to room temperature.

Experimental Results

Sensory Evaluation (Figure 2)

Example 1 Results:

• Milk flavor, cream flavor, butter flavor, and fragrance intensity reached peak values
• Milk flavor was extremely prominent; fragrance intensity was high
• Sour and rancid flavors were significantly lower than the comparative groups
• Off-odors were effectively inhibited
• Sour taste and umami taste were significantly improved
• Salty taste was slightly reduced
• Bitter taste was the lowest among all groups
• Sensory quality was optimally exhibited

Example 2 Results:

• Milk flavor, cream flavor, butter flavor, and fragrance intensity were significantly reduced compared to Example 1, but still higher than comparative examples
• Sour and rancid taste improved compared to Example 1
• Sour taste reached the highest level
• Umami taste remained higher
• Bitter taste significantly increased
• Sour taste was too prominent and bitter taste rose, causing some taste indices to change negatively

Example 3 Results:

• Milk flavor, cream flavor, butter flavor, and aroma intensity continuously decreased
• Milk-type aroma was weaker than the comparative example
• Aroma intensity still higher than the comparative example
• Sour and rancid taste further rose, approaching the level of the comparative example
• Sour taste, umami, salty taste, and bitter taste all showed a tendency to fall back
• Several flavor indices greatly reduced; sensory quality decreased

Comparison:

• Compared to Comparative Examples 1–3, Examples 1–3 showed improved butter flavor, sour flavor, umami, and aroma intensity
• Reduced bad flavors such as sour/rancid and bitter taste
• Sensory scores demonstrate that hot shearing combined with ultra-high pressure treatment significantly enhanced aroma of natural cheese essence

Volatile Flavor Content (Figure 3)

Key Findings:

• 26 aroma components detected, including: 13 acids, 5 ketones, 3 aldehydes, 2 esters, 2 alcohols, 1 aromatic
• Comparative examples had the lowest total volatile flavor content, lower overall abundance, and insufficient flavor complexity and intensity
• Acid compounds were dominant in comparative examples, with other components in very small proportion
• Examples showed high acid-yielding substance content with synchronous increase in other components
• Ultra-high pressure treatment promoted generation of acid-ketone flavor substances, increasing flavor richness and richness
• Example 3 showed reduced content of some substances, indicating excessive pressure inhibited generation of certain components

Free Amino Acid Content (Figure 4)

Key Findings:

• Comparative example had the highest total free amino acid content (exceeding 2.2 g/100g)
• Example 1 total content significantly reduced (approximately 1.4 g/100g)
• Example 2 (approximately 1.8 g/100g) and Example 3 (approximately 1.7 g/100g) rose back but remained lower than the comparative example
• Ratios of various amino acids (lysine, cysteine, tyrosine, etc.) differed significantly across groups
• Hydrophobic amino acid content: Comparative >2.3 g/100g; Example 1: 1.05 g/100g (significant decrease); Examples 2 and 3: 1.6 g/100g and 1.55 g/100g respectively (raised back compared to Example 1)
• Hydrophilic amino acid content: Comparative ~1.05 g/100g; Example 1 reduced to ~0.3 g/100g; Example 2 raised to ~0.55 g/100g; Example 3 dropped to ~0.45 g/100g
• Comparative examples showed largely reduced hydrophobic amino acid ratio, which are core components of bitter peptides
• Ultra-high pressure treatment effectively inhibits formation of bitter peptides enriched with hydrophobic amino acids
• This finding correlates with reduced bitterness observed in sensory evaluation

Free Fatty Acid Content (Figure 5)

Key Findings:

• Comparative example: Highest total free fatty acid content, extremely high total abundance
• Comparative fatty acid composition: Long-chain fatty acids (palmitic acid, stearic acid) and trans fatty acids as main components; short-chain fatty acid ratio extremely small
• Example 1: Reduced total content; absolute content of long-chain/trans-fatty acids greatly reduced; relative proportion of short-chain fatty acids (caproic acid, caprylic acid) improved; composition shifted to mainly short-chain fatty acids
• Examples 2 and 3: Total content continuously reduced; absolute content of various fatty acids further reduced; ratio of long-chain and trans fatty acids continuously compressed; relative ratio of short-chain fatty acids maintained at lower level; overall fatty acid abundance significantly lower than comparative example

Conclusion: Ultra-high pressure treatment has a significant effect on the content and composition of free fatty acids in natural cheese flavor, thereby achieving improvement in its flavor.

Drawings

The patent includes the following figures:

• FIG. 1: Process flow diagram of natural cheese flavor production
• FIG. 2: Sensory evaluation flavor radar diagram for different natural cheese flavors
• FIG. 3: Volatile flavor content plot of different natural cheese flavors
• FIG. 4: Free amino acid content plot of different natural cheese flavors
• FIG. 5: Free fatty acid content stacking plot of different natural cheese flavors

Summary of Technical Contribution

1. Novel Combination of Technologies: The invention creatively combines ultra-high pressure treatment with thermal shearing and enzymatic hydrolysis, which has not been previously reported.
2. Optimal Process Parameters: The invention defines specific conditions for:
   • Raw material composition and proportions
   • Thermal shearing conditions (temperature, speed, time)
   • Ultra-high pressure conditions (pressure level, temperature, duration)
   • Enzyme types, activities, and dosages
   • Enzymatic hydrolysis conditions (temperature, time, pH)
   • Pasteurization conditions
3. Demonstrated Superiority: Comparative testing shows that ultra-high pressure pretreatment before enzymatic hydrolysis provides superior results compared to:
   • No UHP treatment
   • UHP treatment after enzymatic hydrolysis
   • Conventional heating and stirring
4. Mechanistic Understanding: The invention demonstrates that UHP pretreatment:
   • Destroys cheese curd microstructure for better substrate accessibility
   • Reduces formation of bitter peptides by altering protein hydrolysis pathways
   • Modifies fatty acid composition to enhance desirable flavor characteristics
   • Preserves heat-sensitive flavor compounds through non-thermal processing
5. Practical Applicability: The method is validated for natural cheese essence production with clear improvements in sensory quality, volatile flavor content, amino acid profile, and fatty acid composition.

Conclusion

The present invention provides a method for improving quality characteristics of cheese essence through the synergistic combination of hot shearing, ultra-high pressure pretreatment, and enzymatic hydrolysis with proteases and lipases. The method achieves:

• Enhanced flavor intensity and richness
• Improved flavor harmony with reduced bitterness and off-notes
• Preservation of natural, fresh flavor characteristics
• Increased proportion of desirable short-chain fatty acids
• Reduced formation of bitter peptides
• Superior sensory properties compared to conventional methods

The optimal embodiment (Example 1 with 200 MPa UHP treatment) demonstrates the best balance of flavor enhancement, pleasant characteristics, and reduction of undesirable flavors, making it particularly suitable for commercial production of high-quality natural cheese essence for food applications.

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