Method for targeted masking of Oleocanthal peppery taste in olive oil

Abstract

The invention discloses a method for targeted masking of Oleocanthal spicy taste in olive oil, and belongs to the technical field of edible oil processing and flavor improvement. According to the invention, protein is enriched on an oil / water interface, so that a lysine-enriched functional protein layer is formed. Amino groups such as lysine and the like are subjected to a Schiff base reaction with aldehyde groups of Oleocanthal in an interface microenvironment, and oriented interface modification is carried out on spicy molecules of Oleocanthal. Through the interface enrichment effect, the Schiff base reaction is limited in a limited area of the oil-water interface. The reaction efficiency and selectivity are improved, and interference on other active components and natural flavor substances in the oil phase body is effectively avoided. In conclusion, the invention provides a new technical scheme for efficiently, controllably and selectively masking the pungency of the olive oil by taking the interface Schiff base reaction as a core, and the method has potential application value.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of edible oil processing and flavor improvement, and particularly relates to a method for targeting masking of Oleocanthal pungency in olive oil based on high internal phase emulsion interface Schiff base reaction. BACKGROUND

[0002] Olive oil, especially extra virgin olive oil, has unique nutritional and health value due to its high content of polyphenols and is widely used in diet and functional foods. Its unique pungent taste is mainly caused by a class of phenolic secondary metabolites called Oleocanthal. Studies have shown that Oleocanthal has similar anti-inflammatory activity to ibuprofen and is one of the key components of the health benefits of olive oil. However, the strong pungent taste and throat burning sensation greatly limit the acceptance of consumers and the expansion of application scenarios.

[0003] In the prior art, in order to improve the overall flavor quality of olive oil, the main focus is on removing bitterness, astringency and part of the oxidative off-flavor. Common methods include: (1) adsorption deodorization, removing bitter substances or oxidation products in oil by activated carbon, silica gel or resin, but polyphenols and aromatic components are easily adsorbed at the same time, resulting in a decrease in flavor and nutritional activity; (2) physical deodorization, removing volatile off-flavor molecules by distillation under water vapor or vacuum conditions, which usually requires high temperature operation and can easily cause degradation of heat-sensitive components; (3) heating or oxidation treatment, used to reduce the content of part of the bitter compounds, but can cause oil oxidation and flavor deterioration; (4) dilution or blending method, to moderate the overall sensory stimulation by mixing with other vegetable oils or flavoring media, but the original characteristic flavor of extra virgin olive oil is destroyed. The above methods can improve the bitterness and off-flavor of the oil to some extent, but they do not establish a special mechanism or process path for the pungent taste caused by Oleocanthal. At present, some technologies focus on extracting or enriching Oleocanthal from olive oil to realize its separation and industrial utilization. The goal of this kind of technology is to separate and purify the compound, rather than to achieve in-situ and selective chemical passivation or masking of the pungent site in the oil system. In summary, the prior art still has the following shortcomings: (1) lack of specific masking strategy for Oleocanthal pungent characteristics; (2) low selectivity of traditional deodorization process, causing serious damage to flavor and active ingredients; (3) lack of technical solutions that can weaken the pungent stimulation mildly and controllably in the oil system.

[0004] In order to overcome the shortcomings in the prior art, the present application proposes a new masking method for Oleocanthal pungency in olive oil based on the principle of interface chemical regulation. SUMMARY

[0005] The purpose of this invention is to propose a method for targeting and masking the spiciness of olive oil based on the Schiff base reaction at the high internal phase emulsion interface, in order to solve the problems mentioned in the background art.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: A method for targeting and masking the spiciness of oleocanthal in olive oil includes the following steps: S1. Co-treatment and conformational development of protein solution: Soy protein isolate was dissolved in deionized water for hydration. The resulting protein solution was then placed in a supercritical CO2 treatment device for treatment, followed by rapid depressurization to atmospheric pressure. The pH of the protein solution was adjusted under vigorous stirring, and finally it was transferred to a constant temperature shaker for static incubation. S2. Targeted enzymatic hydrolysis and preparation of hydrolysate: Take the protein solution pretreated in S1, add alkaline protease in proportion, and carry out enzymatic hydrolysis reaction; after the enzymatic hydrolysis is completed, immediately place the reaction vessel in a boiling water bath to heat it to achieve rapid enzyme inactivation; after the enzyme inactivation is completed and cooled to room temperature, centrifuge, collect the supernatant to obtain soybean protein isolate hydrolysate, and store it for later use. S3. Ultrasonic activation of endogenous polyphenols in olive oil: Take extra virgin olive oil and place it in an ultrasonic water bath; S4. Construction of high internal phase emulsion with interfacial Schiff base crosslinking: Take the soy protein isolate hydrolysate prepared in S2, adjust the pH, mix it with the olive oil treated in S3, and preheat it in a constant temperature water bath; homogenize the mixture, perform primary emulsification, and measure the pH of the emulsion again; then continue homogenization, and immediately transfer the emulsion to a constant temperature water bath for static reaction; after the reaction is completed, place the emulsion in an ice-water bath for rapid cooling, and the resulting product is the olive oil high internal phase emulsion stabilized by the interfacial Schiff base reaction.

[0007] Preferably, in S1, the concentration of soy protein isolate is 20–40 mg / mL.

[0008] Preferably, in S1, hydration specifically refers to: after the soy protein isolate is dissolved, it is magnetically stirred overnight at 3~5 ℃ until it is completely hydrated; the treatment conditions of the supercritical CO2 treatment device are: pressure 20~25 MPa, temperature 40~50 ℃, time 0.5~1 h.

[0009] Preferably, in S1, adjusting the pH of the protein solution specifically means first rapidly adjusting the pH of the protein solution to 2.0~4.0, maintaining it for 2~3 min, and then rapidly adjusting it to 8.0~10.0; the temperature of the constant temperature shaker is set to 50~60 ℃, and the incubation time is 5~10 min.

[0010] Preferably, in S2, alkaline protease is added in proportion to carry out the enzymatic hydrolysis reaction, specifically: the hydrolysis temperature is 40-70℃, the hydrolysis pH is 7-10, the alkaline protease is added at an enzyme-to-substrate mass ratio of 6.0%-7.0% (E / S, w / w), and the hydrolysis time is 0.25-3 h.

[0011] Preferably, in S2, the centrifugation conditions are: 0-4 ℃, centrifugation at 4000-6000×g for 10-20 min; the storage temperature of the soy protein isolate hydrolysate obtained after centrifugation is 3-5 ℃.

[0012] Preferably, in S3, the ultrasonic conditions of the ultrasonic water bath are: power 600-700 W, time 10-20 min.

[0013] Preferably, in step S4, the pH of the soy protein isolate hydrolysate is 7.5–8.5; the total time for the two homogenizations is 1–3 min, and the homogenization speed is 11,000–13,000 rpm.

[0014] Preferably, in step S4, the volume ratio of soy protein isolate hydrolysate to olive oil is 1:3~4.

[0015] Preferably, in S4, the constant temperature water bath temperature is 40-60℃, and the water bath time is 15-25 minutes.

[0016] Compared with the prior art, the beneficial effects of the present invention are as follows: (1) This invention innovatively proposes a spiciness modulation strategy based on the Schiff base reaction at the high internal phase emulsion interface. By directionally introducing protein hydrolysates rich in free amino groups at the oil-water interface, a specific Schiff base reaction occurs between these hydrolysates and the aldehyde groups of Oleoocanthal in olive oil. This reaction effectively masks the spiciness functional groups through covalent bonding without destroying the core structure of the Oleoocanthal molecule, thus significantly reducing the spiciness. Compared with traditional physical dilution or chemical refining processes, this invention effectively improves flavor while fully preserving the nutritional and health activities of Oleoocanthal and other polyphenols, resolving the long-standing technical contradiction between "improving flavor" and "preserving activity."

[0017] (2) This invention combines the processes of flavor modification and emulsion structuring into one, utilizing the interfacial Schiff base reaction to integrate the two independent steps of "constructing a stable emulsion interface" and "in-situ fixation of flavor substances". This reaction forms a dense, covalently cross-linked interfacial film to stabilize the emulsion, while simultaneously achieving targeted fixation and masking of endogenous pungent substances in the oil phase, simplifying the process and improving production efficiency.

[0018] (3) The olive oil high internal phase emulsion prepared by the method proposed in this invention has high stability and can be stable for at least 3 months at room temperature.

[0019] (4) The preparation process of this invention is simple, the production cost is low, the nutrients are rich, and the economic value is high. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the accompanying drawings involved in the embodiments are now briefly described. Obviously, the drawings in the following description are merely illustrative of some embodiments of the present invention. For those skilled in the art, other forms of drawings can be constructed based on these drawings without creative effort.

[0021] Figure 1 The images are infrared spectra, in which: (a) hydrolyzed soy protein isolate; (b) olive oil polyphenols; and (c) the emulsion interface phase of Example 1. Figure 2 The images show the appearance of the high internal phase emulsions prepared in Examples 1 and 3 and Comparative Examples 1 and 2 of this invention, and the emulsions after being stored at room temperature for 3 months. Detailed Implementation

[0022] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0023] It should be noted that the following detailed descriptions are exemplary and intended to provide further explanation of this application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains. Embodiments of the invention are described in detail below with reference to the accompanying drawings.

[0024] This invention proposes a novel masking method for the spiciness of oleocanthal in olive oil, based on the principle of interfacial chemical regulation. This method enriches proteins at the oil / water interface, forming a functionalized protein layer enriched with lysine. The amino groups, such as lysine, react with the aldehyde groups of oleocanthal in the interfacial microenvironment via a Schiff base reaction, thus performing interfacial-directed modification of the oleocanthal spiciness molecules. Through the interfacial enrichment effect, the Schiff base reaction is confined to a limited region at the oil-water interface. This not only improves reaction efficiency and selectivity but also effectively avoids interference with other active components and natural flavor substances in the bulk oil phase. Compared with existing physical or chemical deodorization methods, this method has the following advantages: (1) Molecular-level selective masking of the pungent site of Oleoocanthal is achieved through interfacial chemical regulation; (2) The degree of spiciness reduction can be adjusted within the oil system by using mild and controllable operating conditions; (3) Improve reaction efficiency and reduce the impact on other components of oil through the interface enrichment effect.

[0025] In summary, this invention provides a novel, highly efficient, controllable, and selective masking technique for the spiciness of olive oil, centered on an interfacial Schiff base reaction, and possesses potential application value. The invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0026] Example 1: A method for preparing a high internal phase emulsion for masking the pungent flavor of oleocanthal in olive oil based on a Schiff base reaction at the oil / water interface includes the following steps: (1) Synergistic pretreatment and conformational development of protein solutions: 1) Protein hydration: Dissolve soy protein isolate powder in deionized water at a concentration of 30 mg / mL, and stir magnetically overnight at 4 ℃ until fully hydrated; 2) Protein structure loosening treatment based on supercritical CO2: The protein solution was placed in a supercritical CO2 treatment device and treated at 20 MPa and 45 °C for 1 h, and then the pressure was rapidly released to atmospheric pressure; 3) Protein conformation development using dynamic pH switching: Immediately adjust the pH of the above protein solution to 3.0 under vigorous stirring, maintain for 2 min, and then rapidly adjust the pH to 9.0. Finally, transfer the solution to a 55 °C constant temperature shaker and incubate for 5 min. (2) Preparation of targeted enzymatic hydrolysis and hydrolysis products: Take the protein solution obtained in step (1) and add alkaline protease at a ratio of 6.7% (w / w) of enzyme to substrate. Perform enzymatic hydrolysis at 55 ℃ and 120 rpm for 60 min. After the enzymatic hydrolysis is completed, immediately place the reaction vessel in a boiling water bath and heat for 10 min to achieve rapid enzyme inactivation. After cooling to room temperature, centrifuge at 4 ℃ and 5000×g for 15 min, collect the supernatant, and obtain the soy protein isolate hydrolysate. Store at 4 ℃ for later use. (3) Ultrasonic activation of endogenous polyphenol components in olive oil: Extra virgin olive oil with a polyphenol content ≥400 mg / kg was placed in an ultrasonic water bath; the ultrasonic power was set to 700 W, and the oil phase temperature was controlled at 25 ℃ by circulating water bath. The ultrasonic treatment lasted for 15 min to activate the oil phase and promote the release of endogenous polyphenols. (4) Construction of high internal phase emulsions by interfacial Schiff base crosslinking: Take 25 mL of the hydrolysate obtained in step (2), adjust the pH to 8.0, mix it with 75 mL of the olive oil obtained in step (3), and preheat it in a constant temperature water bath at 50 ℃ for 5 min; homogenize the mixture at 12000 rpm for 60 s; after primary emulsification, check the pH of the emulsion again and adjust it precisely to 8.0; then, continue to homogenize at the same speed of 12000 rpm for 90 s; immediately transfer the emulsion to a constant temperature water bath at 50 ℃ and let it stand for 20 min; after the reaction is completed, place the emulsion in an ice water bath for rapid cooling, and the product obtained is the olive oil high internal phase emulsion stabilized by the interfacial Schiff base reaction.

[0027] The experimental results showed that the Oleocanthal obtained in this embodiment had an interfacial binding rate of 80.79% and an olive polyphenol retention rate of 93.20%.

[0028] Example 2: The steps in this embodiment are basically the same as those in Example 1, except that the enzymatic hydrolysis reaction time in step (2) is 15 min.

[0029] The experimental results showed that the Oleocanthal interface binding rate obtained in this embodiment was 71.81%.

[0030] Example 3: The steps in this embodiment are basically the same as those in Example 1, except that the enzymatic hydrolysis reaction time in step (2) is 3 hours.

[0031] The experimental results showed that the Oleocanthal interface binding rate obtained in this embodiment was 77.88%.

[0032] Example 4: The steps in this embodiment are basically the same as those in embodiment 1, except that the ultrasound time in step (3) is 10 min.

[0033] The experimental results showed that the Oleocanthal interface binding rate obtained in this embodiment was 73.65%.

[0034] Example 5: The steps in this embodiment are basically the same as those in Example 1, except that the pH of the system in step (4) is 8.5.

[0035] The experimental results showed that the Oleocanthal interface binding rate obtained in this embodiment was 74.69%.

[0036] Example 6: The steps in this embodiment are basically the same as those in Example 1, except that the pH of the system in step (4) is 7.5.

[0037] The experimental results showed that the Oleocanthal interface binding rate obtained in this embodiment was 70.28%.

[0038] Comparative Example 1: The steps of this comparative example are basically the same as those of Example 1. The difference is that in step (2), no enzymatic hydrolysis is performed. Instead, the protein solution pretreated with supercritical CO2 and dynamic pH is directly inactivated, centrifuged, and then used. The specific details are as follows: (1) Synergistic pretreatment and conformational development of protein solutions: 1) Protein hydration: Dissolve soy protein isolate powder in deionized water at a concentration of 30 mg / mL, and stir magnetically overnight at 4 ℃ until fully hydrated; 2) Protein structure loosening treatment based on supercritical CO2: The protein solution was placed in a supercritical CO2 treatment device and treated at 20 MPa and 45 °C for 1 h, and then the pressure was rapidly released to atmospheric pressure; 3) Protein conformation development using dynamic pH switching: Immediately adjust the pH of the above protein solution to 3.0 under vigorous stirring, maintain for 2 min, and then quickly adjust the pH to 9.0; finally, transfer the solution to a 55 ℃ constant temperature shaker and incubate for 5 min. (2) Ultrasonic activation of endogenous polyphenol components in olive oil: Extra virgin olive oil with a polyphenol content ≥400 mg / kg was placed in an ultrasonic water bath; the ultrasonic power was set to 700 W, and the oil phase temperature was controlled at 25 ℃ by circulating water bath. The ultrasonic treatment lasted for 15 min to activate the oil phase and promote the release of endogenous polyphenols. (3) Construction of high internal phase emulsions by interfacial Schiff base crosslinking: Take 25 mL of the protein solution obtained in step (1), adjust the pH to 8.0, mix it with 75 mL of the olive oil obtained in step (2), and preheat it in a constant temperature water bath at 50 ℃ for 5 min; homogenize the mixture at 12000 rpm for 60 s; after primary emulsification, check the pH of the emulsion again and adjust it precisely to 8.0; then, continue to homogenize at the same speed of 12000 rpm for 90 s; immediately transfer the emulsion to a constant temperature water bath at 50 ℃ and let it stand for 20 min; after the reaction is completed, place the emulsion in an ice water bath for rapid cooling, and the product obtained is the olive oil high internal phase emulsion stabilized by the interfacial Schiff base reaction.

[0039] The experimental results showed that the Oleocanthal interface binding rate obtained in this embodiment was 63.02%.

[0040] Comparative Example 2: The steps of this comparative example are basically the same as those of Example 1, except that the pH of the system in step (4) is 7.0.

[0041] The experimental results showed that the Oleocanthal interface binding rate obtained in this embodiment was 56.49%.

[0042] Comparative Example 3: The steps of this comparative example are basically the same as those in Example 1, except that a 30 mg / mL sucrose fatty acid ester solution is used instead of the protein hydrolysate in Example 1 as an emulsifier. The specific details are as follows: (1) Preparation of sucrose fatty acid ester solution: Take sucrose fatty acid ester and dissolve it in deionized water at a concentration of 30 mg / mL by magnetic stirring. (2) Ultrasonic activation of endogenous polyphenol components in olive oil: Extra virgin olive oil with a polyphenol content ≥400 mg / kg was placed in an ultrasonic water bath; the ultrasonic power was set to 700 W, and the oil phase temperature was controlled at 25 ℃ by circulating water bath. The ultrasonic treatment lasted for 15 min to activate the oil phase and promote the release of endogenous polyphenols. (3) Preparation of high internal phase emulsions: Take 25 mL of the sucrose fatty acid ester solution prepared in step (1), adjust the pH to 8.0, mix it with 75 mL of olive oil prepared in step (2), and preheat it in a constant temperature water bath at 50 ℃ for 5 min; homogenize the mixture at 12000 rpm for 60 s; after primary emulsification, check the pH of the emulsion again and adjust it precisely to 8.0; then, continue homogenizing at the same speed of 12000 rpm for 90 s; immediately transfer the emulsion to a constant temperature water bath at 50 ℃ and let it stand for 20 min; after the reaction is completed, place the emulsion in an ice water bath for rapid cooling to obtain olive oil high internal phase emulsion.

[0043] The experimental results showed that the Oleocanthal interface binding rate obtained in this embodiment was 13.57%.

[0044] Based on the above embodiments and comparative examples, the performance of the prepared olive oil high internal phase emulsion was characterized, and the specific details are as follows: (1) Determination of spiciness masking rate: The spiciness intensity of the emulsion was evaluated using a sensory analysis scaling method. The spiciness masking rate was calculated based on the intensity ratio between the treated and control groups. The process followed the ISO 8589-2007 standard. Ten sensory evaluators (aged 20-28 years) were selected and trained. A spiciness intensity scale was established using phenol-free olive oil, medium-phenol content olive oil, and high-phenol content olive oil as references (corresponding to intensity values ​​of 0, 5, and 10, respectively). During evaluation, 1.0 g of sample was held in the mouth for 10 seconds and then spat out. After rinsing the mouth, the spiciness intensity value was recorded. Each sample was evaluated three times. The results are shown in Table 1.

[0045] Table 1

[0046] The results showed that the spiciness intensity of the emulsions prepared in Examples 1-6 was significantly reduced, with a spiciness masking rate of over 80%. In contrast, Comparative Example 1 suffered from insufficient interfacial reaction due to inadequate exposure of protein amino groups, and Comparative Example 2 suffered from low Schiff base reaction efficiency due to unsuitable pH conditions, resulting in a more pronounced spiciness. Comparative Example 3, relying solely on physical embedding, experienced easy release of the oil phase during oral processing, leading to a strong perception of spiciness. These results demonstrate that the present invention effectively inhibits the binding of Oleoocanthal to oral receptors through interfacial Schiff base reaction, achieving a long-lasting spiciness masking effect.

[0047] (2) Determination of the interfacial bonding rate of Oleoocanthal: To quantitatively characterize the interfacial reaction efficiency, phase partition analysis was performed on Oleoocanthal in the emulsion. The emulsion was frozen overnight, then thawed, and centrifuged to obtain the interfacial layer, oil phase, and aqueous phase. Each component was collected, concentrated by nitrogen blowing, and then reconstituted with a methanol-water solution (8:2, v / v) containing 0.015 mg / mL syringic acid (as internal standard). The Oleoocanthal content was determined using an Agilent 1220 Infinity II high-performance liquid chromatography system. The interfacial binding rate was calculated using the difference method (i.e., the total amount of Oleoocanthal in the initial oil phase minus the amount free in the oil and aqueous phases), and the results are shown in Table 2.

[0048] Table 2

[0049] As shown in Table 2, the Oleocanthal interfacial binding rate in Examples 1-6 was all above 70%, significantly better than that in the comparative examples. This fully demonstrates that the hydrolyzed soybean protein provided by this invention can be efficiently and specifically immobilized at the emulsion interface through an interfacial Schiff base reaction with Oleocanthal.

[0050] (3) Infrared spectral verification of the interfacial Schiff base reaction: To confirm that covalent cross-linking had indeed occurred at the interface, Fourier transform infrared spectroscopy analysis was performed on key samples. The freeze-dried hydrolyzed soy protein isolate, olive oil polyphenol extract, and the emulsion interfacial phase from Example 1 were respectively ground and compressed with potassium bromide at a ratio of 1:100 (w / w). The results were analyzed using a Nicolet iS50 spectrometer at 4000-400 cm⁻¹. -1 Scan within the range (resolution 4cm) -1 (Potassium bromide was used as a background). The results are as follows. Figure 1 As shown.

[0051] Among them, hydrolyzed soy protein isolate at 3300 cm -1 A peak of NH / OH stretching vibration appears at 1650 cm⁻¹, and at 1650 cm⁻¹... -1 and 1540 cm -1 The peaks at 1740-1700 cm⁻¹ show characteristic peaks for amide I and amide II; olive oil polyphenols show peaks at 1740-1700 cm⁻¹. -1 An absorption peak for the carbonyl group C=O appears at 1200-1000 cm⁻¹. -1 A CO vibration peak appeared in the range. Compared with the control, the emulsion interfacial phase showed a peak at 1620 cm⁻¹. -1 A new C=N stretching vibration peak appears at 3300 cm⁻¹. -1 NH absorption peak and 1700 cm⁻¹ -1 The weakening of the C=O peaks indicates that the oleocanthal aldehyde group and the protein amino group underwent a Schiff base reaction at the interface.

[0052] (4) Determination of emulsion storage stability: The emulsions from Examples 1, 3, and Comparative Examples 1 and 2 were stored at room temperature away from light, and their physical stability was observed. The results are as follows: Figure 2 As shown.

[0053] The emulsions of Example 1 and Comparative Example 1 remained homogeneous after 3 months of storage, without phase separation, demonstrating good long-term stability. However, in Example 3, the excessively long enzymatic hydrolysis time resulted in excessively short peptides and insufficient interfacial film strength, ultimately leading to demulsification. In Comparative Example 2, because the reaction pH was close to the isoelectric point of soybean protein, the interfacial charge repulsion was weakened, and the emulsion underwent phase separation only after 15 days. These results demonstrate that the present invention, through optimized process parameters, can achieve both spiciness masking and ensure excellent physical stability of the emulsion system.

[0054] In summary, the performance characterization results demonstrate that the hydrolyzed soy protein isolate prepared using a specific process, as an interfacial reactant, can undergo a highly efficient interfacial Schiff base reaction with oleocanthal in olive oil, covalently anchoring it at the emulsion interface. This achieves spiciness masking at the molecular level and simultaneously constructs a stable emulsion structure. This method is simple, highly effective, and effectively preserves the nutritional and active components of olive oil while improving flavor, exhibiting significant industrial application value.

[0055] Unless otherwise specified, all raw materials used in this invention are existing substances that can be purchased directly from the market.

[0056] The above specific embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Those skilled in the art should understand that the above embodiments do not limit the present invention in any way, and all similar technical solutions obtained by equivalent substitution or equivalent transformation are within the protection scope of the present invention.

Claims

1. A method for targeting and masking the spiciness of oleocanthal in olive oil, characterized in that, Includes the following steps: S1. Co-treatment and conformational development of protein solution: Soy protein isolate was dissolved in deionized water for hydration. The resulting protein solution was then placed in a supercritical CO2 treatment device for treatment, followed by rapid depressurization to atmospheric pressure. The pH of the protein solution was adjusted under vigorous stirring, and finally it was transferred to a constant temperature shaker for static incubation. S2. Targeted enzymatic hydrolysis and preparation of hydrolysate: Take the protein solution pretreated in S1, add alkaline protease in proportion, and carry out enzymatic hydrolysis reaction; after the enzymatic hydrolysis is completed, immediately place the reaction vessel in a boiling water bath to heat it to achieve rapid enzyme inactivation; after the enzyme inactivation is completed and cooled to room temperature, centrifuge, collect the supernatant to obtain soybean protein isolate hydrolysate, and store it for later use. S3. Ultrasonic activation of endogenous polyphenols in olive oil: Take extra virgin olive oil and place it in an ultrasonic water bath; S4. Construction of high internal phase emulsion with interfacial Schiff base crosslinking: Take the soy protein isolate hydrolysate prepared in S2, adjust the pH, mix it with the olive oil treated in S3, and preheat it in a constant temperature water bath; homogenize the mixture, perform primary emulsification, and measure the pH of the emulsion again; then continue homogenization, and immediately transfer the emulsion to a constant temperature water bath for static reaction; after the reaction is completed, place the emulsion in an ice-water bath for rapid cooling, and the resulting product is the olive oil high internal phase emulsion stabilized by the interfacial Schiff base reaction.

2. The method for targeting and masking the spiciness of oleocanthal in olive oil according to claim 1, characterized in that, In S1, the concentration of soy protein isolate is 20–40 mg / mL.

3. The method for targeting and masking the spiciness of oleocanthal in olive oil according to claim 1, characterized in that, In S1, hydration specifically refers to: after the soy protein isolate is dissolved, it is magnetically stirred overnight at 3~5 ℃ until it is completely hydrated; the treatment conditions of the supercritical CO2 treatment device are: pressure 20~25 MPa, temperature 40~50 ℃, time 0.5~1 h.

4. The method for targeting and masking the spiciness of oleocanthal in olive oil according to claim 1, characterized in that, In S1, adjusting the pH of the protein solution specifically means first rapidly adjusting the pH of the protein solution to 2.0~4.0, maintaining it for 2~3 minutes, and then rapidly adjusting it to 8.0~10.0; The temperature of the constant temperature shaker is set to 50~60 ℃, and the incubation time is 5~10 min.

5. The method for targeting and masking the spiciness of oleocanthal in olive oil according to claim 1, characterized in that, In S2, alkaline protease is added in proportion for enzymatic hydrolysis. Specifically, the hydrolysis temperature is 40–70 °C, the hydrolysis pH is 7–10, the alkaline protease is added at an enzyme to substrate mass ratio of 6.0%–7.0% (E / S, w / w), and the hydrolysis time is 0.25–3 h.

6. The method for targeting and masking the spiciness of oleocanthal in olive oil according to claim 1, characterized in that, In S2, the centrifugation conditions are: 0–4 ℃, centrifugation at 4000–6000×g for 10–20 min; the storage temperature of the soy protein isolate hydrolysate obtained after centrifugation is 3–5 ℃.

7. The method for targeting and masking the spiciness of oleocanthal in olive oil according to claim 1, characterized in that, In S3, the ultrasonic conditions for the ultrasonic water bath are: power 600-700 W, time 10-20 min.

8. The method for targeting and masking the spiciness of oleocanthal in olive oil according to claim 1, characterized in that, In S4, the pH of the soy protein isolate hydrolysate is 7.5–8.5; the total time for two homogenizations is 1–3 min, and the homogenization speed is 11000–13000 rpm.

9. The method for targeting and masking the spiciness of oleocanthal in olive oil according to claim 1, characterized in that, In S4, the volume ratio of soy protein isolate hydrolysate to olive oil is 1:3~4.

10. The method for targeting and masking the spiciness of oleocanthal in olive oil according to claim 1, characterized in that, In S4, the constant temperature water bath is 40-60℃, and the water bath time is 15-25 minutes.

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