Food-grade liquid antioxidant and preparation method and application thereof

Abstract

The application discloses a kind of food-grade liquid antioxidant and its preparation method and application, belong to food additive technical field.The antioxidant with liquid edible oil as liquid carrier, uniformly dissolved in it, antioxidant component content can be wide range control.Preparation method includes two paths: one is directly added to liquid edible oil, inert gas protection under heating stirring to completely dissolved to obtain product;Second is to dissolve solid antioxidant in ethanol to obtain the first solution, mixed with liquid edible oil under inert gas protection, and the product is obtained by removing ethanol.The product of the application is liquid, stable and easy to use, no solvent residue hidden danger, easy to add accurately, uniformly dispersed in edible oil, baked food, meat products, cosmetics and other systems, solve the application problem of ordinary solid antioxidant, unevenly dispersed, can effectively delay food oxidation, improve storage stability, and has wide application prospect.

Description

Technical Field

[0001] This invention relates to the field of food additives, specifically to a liquid composite antioxidant with high solubility, stability and ease of application, its preparation method and its application in oils and oily foods. Background Technology

[0002] Oxidation is a major cause of quality deterioration in oils and oily foods (such as rancidity, decreased nutritional value, color changes, and the formation of potentially harmful substances). Solid antioxidants, such as ascorbate palmitate (AP), are a class of highly effective and safe food-grade fat-soluble antioxidants. Their antioxidant effect is superior to that of tocopherol, and they can produce a synergistic effect with tocopherol. However, most solid antioxidants are in powder form at room temperature and have limited solubility in oils, especially at lower temperatures where they tend to precipitate, affecting their uniform dispersion and the full realization of their antioxidant efficacy. This poses inconvenience for food industrial production where addition and mixing at room temperature or low temperature are required.

[0003] In existing technologies, solid antioxidant powders are typically mixed directly with oils and heated to dissolve. However, this process is time-consuming and energy-intensive, and improper handling after cooling can easily lead to the recrystallization and precipitation of the antioxidants. Some studies have also attempted to dissolve them in organic solvents such as ethanol, but if the solvent is not completely removed, it will affect the flavor of the food, and a single solvent system is not effective for the long-term stable preservation of solid antioxidants.

[0004] Therefore, developing a liquid formulation that can stably and efficiently dissolve solid antioxidants at high concentrations, and that can be easily added and uniformly dispersed at room temperature in various oil and food systems, has significant industrial application value. Summary of the Invention

[0005] Based on the deficiencies of the prior art, the present invention aims to overcome the shortcomings of the prior art and provide a food-grade liquid composite antioxidant that is simple to prepare, has good stability, and high antioxidant efficacy.

[0006] To achieve the above objectives, the present invention first provides a food-grade liquid antioxidant, wherein the food-grade liquid antioxidant is composed of a solid antioxidant uniformly dispersed in a liquid edible oil carrier; the amount of the solid antioxidant added is 0.5% to 15% of the mass of the liquid edible oil carrier; the liquid edible oil carrier is a liquid glyceride, or a mixture of one or more of the following: liquid glyceride and diglyceride oil, medium-chain triglycerides, and vegetable oil in a mass ratio of 5:1 to 20:1; the liquid glyceride is composed of monoglycerides, diglycerides, and triglycerides, and based on the total mass of the liquid glyceride as 100%, the mass percentage of the monoglycerides is 30% to 60%, the mass percentage of the diglycerides is 30% to 50%, and the mass percentage of the triglycerides is 10% to 30%, and the sum of the mass percentages of the three is 100%.

[0007] Preferably, the solid antioxidant is selected from one or more of tea polyphenols, rosemary extract, propyl gallate, ascorbyl palmitate, and tea polyphenol palmitate.

[0008] Preferably, based on the total mass of fatty acids constituting monoglycerides, diglycerides, and triglycerides in the liquid glycerides as 100%, the mass percentage of saturated fatty acids is <10%, and the mass percentage of unsaturated fatty acids is ≥90%; specifically, it is any combination of palmitic acid, oleic acid, linoleic acid, and linolenic acid.

[0009] Its beneficial effects are as follows: In the food-grade liquid antioxidant prepared by this invention, the liquid edible oil carrier is not merely used as a common oil dilution carrier, but rather, through the controlled ratio of monoglycerides to diglycerides, a suitable composite microenvironment for the stable dispersion and dissolution of ascorbate palmitate is constructed. Ascorbate palmitate molecules contain both hydrophilic ascorbic acid groups and lipophilic palmitoyl chains, which are prone to aggregation or crystallization in ordinary oils due to insufficient solubilization of polar groups and intermolecular hydrogen bonding. Monoglycerides contain more free hydroxyl groups, which can form hydrogen bonds or dipole interactions with the polar groups of ascorbate palmitate, thereby helping to weaken the self-aggregation of ascorbate palmitate molecules; diglycerides have better oil-phase compatibility, improving the liquid flowability and hydrophobic phase continuity of the system. When the monoglyceride content is too high, the system becomes overly polar, and the monoglyceride molecules themselves tend to form an ordered arrangement or crystalline structure, leading to increased viscosity, decreased transparency, and even precipitation. Conversely, when the diglyceride content is too high, the system lacks sufficient polarity, making it difficult to fully solubilize the polar groups of ascorbate palmitate, which also results in decreased solubility stability. Therefore, only within the specific ratio range of monoglycerides to diglycerides defined in this invention can a balance be achieved between polarity, hydrophobic compatibility, and crystallization inhibition, allowing the poorly soluble solid antioxidant to form a stable and homogeneous liquid system in the liquid glyceride carrier.

[0010] The food-grade liquid antioxidant is pale yellow or light brown, a viscous liquid or paste, and its physicochemical properties must meet the following requirements: moisture ≤1.0%, free glycerol ≤7.0%, acid value (calculated as KOH) ≤4.0 mg / g, soap content (calculated as sodium oleate) ≤6.0%, free fatty acids ≤3.0 mg / g, freezing point <15℃, viscosity 20-500 mPa·s, and peroxide value <0.25 g / 100g.

[0011] Secondly, the present invention provides a method for preparing the food-grade liquid antioxidant as described above, wherein the method specifically comprises: Under inert gas protection, solid antioxidants are stirred and mixed with liquid edible oil carriers to uniformly disperse them in the liquid edible oil carriers, resulting in a homogeneous liquid mixture, which is the food-grade liquid antioxidant.

[0012] Alternatively, the solid antioxidant is first dissolved in ethanol to form a first solution; then, under the protection of an inert gas, the first solution is stirred and mixed with a liquid edible oil carrier to fully dissolve and disperse the solid antioxidant in the liquid edible oil carrier, resulting in a homogeneous liquid mixture. The ethanol is then removed to obtain the food-grade liquid antioxidant.

[0013] The beneficial effects are as follows: Ascorbyl palmitate itself is an antioxidant, and its ascorbic acid structure is easily oxidized under conditions of heating, the presence of oxygen, and trace amounts of metal ions. The preparation process typically requires heating and stirring to promote dissolution. If carried out in air, oxygen from the air will continuously enter the system, causing premature oxidation and consumption of ascorbyl palmitate, potentially leading to a decrease in the content of active ingredients, darkening of color, changes in odor, and reduced subsequent storage stability. On the other hand, if the liquid carrier contains vegetable oil or unsaturated fatty acid components, heating and contact with air may also promote carrier oxidation, producing peroxides or polar oxidation products. These oxidation products may affect the stable dispersion of ascorbyl palmitate in the system, thereby increasing the risk of turbidity, precipitation, or decreased activity. Therefore, preparation under an inert gas atmosphere can reduce the dissolved oxygen and headspace oxygen content in the system, reducing the oxidation loss of ascorbyl palmitate and the oil carrier during heating and stirring, thereby improving the retention rate of active ingredients, color stability, and storage stability of the product.

[0014] Preferably, the inert gas is one of nitrogen, argon, and helium; the mixing temperature is 30~100℃.

[0015] Preferably, the ethanol removal method is vacuum desolvation, with a vacuum degree of -0.05MPa to -0.1MPa and a temperature of 40℃ to 70℃.

[0016] Finally, this invention provides an application of the above-mentioned food-grade liquid antioxidant in oils or oily foods.

[0017] The food-grade liquid antioxidant can be used alone or in combination with one or more of tocopherol, tea polyphenols, rosemary extract, propyl gallate, and tea polyphenol palmitate.

[0018] Preferably, the solid antioxidant in the food-grade liquid antioxidant is ascorbate palmitate, and the mass ratio of ascorbate palmitate to tocopherol in the compound is 1:1 to 1:5; the mass ratio of ascorbate palmitate to tea polyphenols is 1:2 to 1:10; the mass ratio of ascorbate palmitate to rosemary extract is 1:1 to 1:5; the mass ratio of ascorbate palmitate to propyl gallate is 1:1 to 10:1; and the mass ratio of ascorbate palmitate to tea polyphenol palmitate is 1:3 to 1:10.

[0019] The oils and fats include soybean oil, rapeseed oil, peanut oil, olive oil, palm oil, lard, butter, and blended oils thereof; the oily foods include baked goods, fried foods, nut products, mayonnaise, salad dressing, meat products, and instant noodles.

[0020] In summary, this invention provides a food-grade liquid antioxidant, its preparation method, and its application. Compared with the prior art, this invention has the following significant advantages: (1) High solubility and stability: By optimizing the liquid glyceride-based dispersion system, a high-concentration uniform dispersion of solid antioxidants was achieved at higher temperatures, forming a clear and transparent solution. No crystallization occurred during long-term storage, demonstrating excellent stability. The solubility of solid antioxidants in oils and fats increased from less than 0.05% to 5%-10%.

[0021] (2) Convenient to use: The product is liquid and can be directly measured at room temperature or low temperature. It can be diluted hundreds of times and added to the target oil or food without preheating to dissolve, which simplifies the production process and improves production efficiency and accuracy of addition.

[0022] (3) Uniform dispersion: Liquid formulations can ensure that antioxidants are rapidly and uniformly dispersed in the oil matrix, avoiding excessively high or low local concentrations, thereby maximizing their antioxidant effect.

[0023] (4) Synergistic effect and nitrogen protection: Liquid glycerides have certain emulsifying and antioxidant auxiliary effects, and the effect is better when used in combination with solid antioxidants. The inert gas protection throughout the process effectively prevents the solid from being prematurely oxidized and degraded due to contact with oxygen during the preparation process, thus ensuring the activity of the product.

[0024] (5) Wide range of safety: All ingredients are food grade, comply with national food safety standards, and have a wide range of applications. Attached Figure Description

[0025] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0026] Figure 1 The effect of AP direct dispersion-liquid glyceride mixture after standing for 48 hours.

[0027] Figure 2 The dissolution effect of adding AP to different oil carriers. Detailed Implementation

[0028] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0029] It should be noted that the determination of the glycerol ester composition of liquid glycerol esters is mainly performed by gas chromatography. The gas chromatography detection conditions are as follows: The chromatographic column was a DB-5HT (15m × 0.320mm, 0.10μm), with an injection port temperature of 380℃, an injection volume of 1μL, and a split ratio of 50:1. High-purity helium was used as the carrier gas at a flow rate of 2mL / min. The hydrogen flow rate was 32mL / min, and the air flow rate was 200mL / min. An FID detector was used, and the temperature was set at 380℃. The column oven temperature program was as follows: initial temperature 170℃, hold for 2 min, then increase to 380℃ at a rate of 5℃ / min and hold for 6 min.

[0030] The fatty acid composition of liquid glycerides is mainly determined by gas chromatography. The gas chromatography detection conditions are as follows: The column was equipped with a flame ionization detector (FID) and a capillary column (DB-FastFAME, 30m × 0.250 mm × 0.25 μm). The injection volume was 1 μL, the carrier gas (nitrogen) flow rate was set to 2.0 mL / min, and the split ratio was 1:10. The column oven temperature program was 165 °C held for 3.6 min, then increased to 230 °C at a rate of 20 °C / min and held for 6 min. The detector and injection port temperatures were 260 °C and 280 °C, respectively. The fatty acid composition was determined based on the retention time of fatty acid methyl ester standards. The content of each fatty acid was calculated using the peak area normalization method.

[0031] Ascorbate palmitate in liquid glycerides is primarily detected by high-performance liquid chromatography (HPLC). Gas chromatography (GC) detection conditions are as follows: An HPLC system equipped with a photodiode array (PDA) detector was used. The column was a Shim-pack GIS TC18 reversed-phase column (5 μm, 4.6 × 150 mm). The column temperature was set at 35 °C, the mobile phase was methanol / 0.01% acetic acid aqueous solution (9:1, v / v), the flow rate was set at 1 mL / min, and the elution time was 10 min. The detection wavelength was 254 nm, and the injection volume was 5 μL.

[0032] The relevant terms and measurement standards in the embodiments are explained as follows: Unless otherwise stated, "%" in this invention refers to mass percentage, and "ratio" or "comparison" refers to mass ratio. Specifically, the content of monoglycerides, diglycerides, and triglycerides in the liquid glycerides is calculated as 100% of the total mass of the liquid glycerides, and is a mass percentage; the fatty acid composition in the liquid glycerides is calculated as 100% of the total mass of the fatty acids constituting monoglycerides, diglycerides, and triglycerides, and is a mass percentage; the amount of ascorbate palmitate added is the percentage of the mass of ascorbate palmitate relative to the mass of the liquid glycerides; the ascorbate palmitate content in the obtained product is the percentage of the mass of ascorbate palmitate to the total mass of the obtained product. Example 1

[0033] 10g of ascorbyl palmitate (AP) and 100g of liquid glycerides (40% monoglyceride, 50% diglyceride, and 10% triglyceride, with a fatty acid composition of 5.1% saturated fatty acids, 1.8% oleic acid, 81.7% linoleic acid, and 11.4% linolenic acid) were weighed and placed together in a sealed reactor. Nitrogen gas was introduced into the reactor to replace the air. Stirring was started under nitrogen protection, and the stirring temperature was controlled at 100℃. Stirring continued until the AP was completely dissolved, yielding a homogeneous, transparent, light yellow liquid. The liquid was dispensed into brown glass bottles under a nitrogen flow, sealed with nitrogen, and the AP content in the resulting product was 10% of the mass of the liquid glycerides. The physicochemical properties of the resulting product were tested. The results showed that the product had a moisture content of 0.7%, a free glycerol content of 6%, an acid value of 3.8 mg / g (calculated as KOH), a soap content of 4% (calculated as sodium oleate), a free fatty acid content of 2%, a freezing point of 14℃, a viscosity of 400 mPa·s at 25℃, and a peroxide value of 0.20 g / 100g. Example 2

[0034] Weigh 5g of ascorbyl palmitate (AP) and 100g of liquid glycerides (40% monoglyceride, 50% diglyceride, and 10% triglyceride, with a fatty acid composition of 5.1% saturated fatty acids, 1.8% oleic acid, 81.7% linoleic acid, and 11.4% linolenic acid). Place both in a sealed reactor. Purge the reactor with nitrogen to replace the air. Under nitrogen protection, start stirring and maintain the stirring temperature at 100℃. Continue stirring until the AP is completely dissolved, resulting in a homogeneous, transparent, light yellow liquid. Dispense the liquid into brown glass bottles under a nitrogen flow, seal with nitrogen, and the AP content in the obtained product is 5% of the mass of the liquid glycerides. Perform physicochemical tests on the obtained product. The results showed that the product had a moisture content of 0.5%, a free glycerol content of 5%, an acid value of 3.4 mg / g (calculated as KOH), a soap content of 4% (calculated as sodium oleate), a free fatty acid content of 2%, a freezing point of 13℃, a viscosity of 380 mPa·s at 25℃, and a peroxide value of 0.20 g / 100g. Example 3

[0035] 2g of tea polyphenol palmitate and 100g of liquid glycerol ester (40% monoglyceride, 50% diglyceride, and 10% triglyceride, with a fatty acid composition of 5.1% saturated fatty acids, 1.8% oleic acid, 81.7% linoleic acid, and 11.4% linolenic acid) were weighed and placed together in a sealed reactor. Nitrogen gas was introduced into the reactor three times to replace the air. Stirring was started under nitrogen protection, and the stirring temperature was controlled at 80℃. Stirring continued until the tea polyphenol palmitate was completely dissolved, yielding a homogeneous, transparent, reddish-brown liquid. The liquid was rapidly dispensed into brown glass bottles under a nitrogen flow. After dispensing, nitrogen was continued for 30 seconds, and then the bottles were sealed. The mass of tea polyphenol palmitate in the obtained product was 2.0% of the mass of the liquid glycerol ester. The product showed no stratification or precipitation after standing for 48 hours, indicating good stability. The physicochemical properties of the obtained product were tested. The results showed that the product had a moisture content of 0.5%, a free glycerol content of 5%, an acid value of 3.4 mg / g (calculated as KOH), a soap content of 3% (calculated as sodium oleate), a free fatty acid content of 3%, a freezing point of 12℃, a viscosity of 250 mPa·s at 25℃, and a peroxide value of 0.18 g / 100g. Example 4

[0036] 5g of ascorbyl palmitate (AP) and 100g of liquid glycerides (50% monoglyceride, 40% diglyceride, and 10% triglyceride, with a fatty acid composition of 9.1% saturated fatty acids, 63.6% oleic acid, 18.7% linoleic acid, and 8.6% linolenic acid) were weighed and placed together in a sealed reactor. Nitrogen gas was introduced into the reactor three times to replace the air. Stirring was started under nitrogen protection, and the stirring temperature was controlled at 80℃. Stirring continued until the AP was completely dissolved, yielding a homogeneous, transparent, light yellow-brown liquid. The liquid was rapidly dispensed into brown glass bottles under a nitrogen flow. After dispensing, nitrogen was continued for 30 seconds, and then the bottles were sealed. The AP content in the resulting product was 5% of the mass of the liquid glycerides. The resulting product was homogeneous, transparent, and had good flowability, with no precipitation. The physicochemical properties of the resulting product were tested. The results showed that the product had a moisture content of 0.5%, a free glycerol content of 4%, an acid value of 2.8 mg / g (calculated as KOH), a soap content of 4.0% (calculated as sodium oleate), a free fatty acid content of 2.4%, a freezing point of 12℃, a viscosity of 220 mPa·s at 25℃, and a peroxide value of 0.15 g / 100g. Example 5

[0037] Weigh 5g of ascorbyl palmitate (AP) and 100g of liquid glycerides (60% monoglyceride, 30% diglyceride, and 10% triglyceride, with a fatty acid composition of 17.2% saturated fatty acids, 1.6% oleic acid, 71.5% linoleic acid, and 9.7% linolenic acid). Place both in a sealed reactor. Purge the reactor with nitrogen three times to replace the air. Under nitrogen protection, start stirring and maintain the stirring temperature at 100℃. Continue stirring until the AP is completely dissolved, resulting in a homogeneous, transparent, pale yellow liquid. Quickly dispense the liquid into brown glass bottles under a nitrogen flow. After dispensing, continue purging with nitrogen for 30 seconds, then seal. The resulting product contains 5% AP by mass of the liquid glycerides and shows no stratification or precipitation after standing for 48 hours. The physicochemical properties of the obtained product were tested, and the results showed that the product had a moisture content of 0.4%, a free glycerol content of 4.5%, an acid value of 2.9 mg / g (calculated as KOH), a soap content of 4.5% (calculated as sodium oleate), a free fatty acid content of 2.6%, a freezing point of 13℃, a viscosity of 350 mPa·s at 25℃, and a peroxide value of 0.17 g / 100 g. Example 6

[0038] Weigh 2g of ascorbyl palmitate (AP) and 100g of liquid glycerides (40% monoglyceride, 40% diglyceride, and 20% triglyceride, with a fatty acid composition of 15.2% saturated fatty acids, 2.6% oleic acid, 73.5% linoleic acid, and 8.7% linolenic acid). Place both in a sealed reactor. Purge the reactor with nitrogen three times to replace the air. Under nitrogen protection, start stirring and control the stirring temperature at 95℃. Continue stirring until the AP is completely dissolved, resulting in a homogeneous, transparent, pale yellow liquid. Quickly dispense the liquid into brown glass bottles under a nitrogen flow. After dispensing, continue purging with nitrogen for 30 seconds, then seal. The resulting product contains 2.0% AP by mass of the liquid glycerides and shows no stratification or precipitation after standing for 48 hours. The physicochemical properties of the obtained product were tested, and the results showed that the product had a moisture content of 0.4%, a free glycerol content of 3.8%, an acid value of 2.7 mg / g (calculated as KOH), a soap content of 3.8% (calculated as sodium oleate), a free fatty acid content of 2.3%, a freezing point of 11℃, a viscosity of 180 mPa·s at 25℃, and a peroxide value of 0.16 g / 100 g. Example 7

[0039] Weigh 5g of ascorbate palmitate (AP) and add it to 100g of food-grade ethanol (95% vol). Place the mixture in a sealed reactor and purge the air with nitrogen three times (3 minutes each time to ensure no residual air remains in the reactor). Stir and dissolve the mixture under nitrogen protection to obtain a clear and transparent solution A. Weigh 100g of liquid glycerides (40% monoglyceride, 50% diglyceride, and 10% triglyceride, with a fatty acid composition of 5.1% saturated fatty acids, 1.8% oleic acid, 81.7% linoleic acid, and 11.4% linolenic acid) and place it in another container equipped with a stirrer. Simultaneously purge with nitrogen protection and maintain a stirring rate of 250 rpm. While continuously purging with nitrogen and stirring in both containers, slowly pour solution A into the liquid glycerides at a rate of 10 mL / min to avoid localized high concentrations that could cause stratification. After the addition is complete, heat to 60℃ and continue stirring at this temperature for 30 minutes to obtain a homogeneous, transparent, light yellow liquid. Subsequently, a vacuum solvent removal process was performed (vacuum degree -0.1 MPa, temperature 40℃, solvent removal time 30 min to remove ethanol from the system). After solvent removal, the liquid was rapidly dispensed into brown glass bottles under a nitrogen flow, and after dispensing, nitrogen was continued for 30 s before sealing. The AP content in the obtained product was 5% of the mass of the liquid glycerides. After standing for 48 h, there was no stratification or precipitation, indicating good stability. Physicochemical index testing of the obtained product showed that the moisture content was 0.8%, the free glycerol content was 4.2%, the acid value (calculated as KOH) was 3.2 mg / g, the soap content (calculated as sodium oleate) was 4.1%, the free fatty acid content was 2.5%, the freezing point was 12℃, the viscosity at 25℃ was 280 mPa·s, and the peroxide value was 0.14 g / 100 g. Example 8

[0040] Weigh 10g of tea polyphenol palmitate and add it to 200g of food-grade ethanol (95% vol). Place the mixture in a sealed reactor and purge the air with nitrogen three times (3 min each time). Under nitrogen protection, stir at 350 rpm and maintain the temperature at 30°C for 10 min to obtain a clear solution A. Weigh 100g of liquid glycerol ester (40% monoglyceride, 50% diglyceride, and 10% triglyceride, with a fatty acid composition of 5.1% saturated fatty acids, 1.8% oleic acid, 81.7% linoleic acid, and 11.4% linolenic acid), place it in another container, and purge with nitrogen. Stir at 250 rpm. While continuously purging with nitrogen and stirring, slowly pour solution A into the glycerol ester at a rate of 8 mL / min. After the addition is complete, heat to 60°C and stir for 30 minutes to obtain a homogeneous, transparent, reddish-brown liquid. After removing ethanol through vacuum solvent removal (-0.1 MPa, 40℃, solvent removal time 40 min), the product was dispensed into brown glass bottles under nitrogen flow and sealed with nitrogen. The mass of tea polyphenol palmitate in the obtained product was 10% of that in liquid glycerol esters, and no precipitation occurred after standing for 72 h. Physicochemical indicators of the obtained product were tested, and the results showed that the product had a moisture content of 0.9%, a free glycerol content of 4.3%, an acid value (based on KOH) of 3.1 mg / g, a soap content (based on sodium oleate) of 4.2%, a free fatty acid content of 2.5%, a freezing point of 13℃, a viscosity of 380 mPa·s at 25℃, and a peroxide value of 0.13 g / 100 g. Example 9

[0041] Weigh 20g of ascorbate palmitate (AP) and add it to 200g of food-grade ethanol (95% vol). Place the mixture in a sealed reactor and purge the air with nitrogen four times (2 min each time). Under nitrogen protection, stir at 280 rpm and maintain the temperature at 30°C for 10 min to obtain a clear solution A. Weigh 100g of liquid glycerides (40% monoglyceride, 50% diglyceride, and 10% triglyceride, with a fatty acid composition of 5.1% saturated fatty acids, 1.8% oleic acid, 81.7% linoleic acid, and 11.4% linolenic acid) and place them in another container. Purge with nitrogen and maintain the stirring speed at 250 rpm. Slowly pour solution A into the glycerides at a rate of 12 mL / min while continuously stirring with nitrogen. After the addition is complete, maintain the temperature at 60°C and stir for 30 minutes to obtain a homogeneous, transparent, light yellow-brown liquid (the color is slightly darker due to the unsaturated fatty acids). After vacuum desolventizing (-0.05 MPa, 45℃, desolventizing time 60 min), the product was dispensed and sealed under a nitrogen flow. The AP content in the obtained product was 20% of the mass of the liquid glycerides. The high linoleic acid composition gave the product excellent low-temperature fluidity, and it did not solidify after standing for 24 hours, exhibiting good stability. Physicochemical indicators of the obtained product were tested, and the results showed that the product had a moisture content of 0.9%, a free glycerol content of 4.8%, an acid value of 3.6 mg / g (based on KOH), a soap content of 4.9% (based on sodium oleate), a free fatty acid content of 2.8%, a freezing point of 14℃, a viscosity of 460 mPa·s at 25℃, and a peroxide value of 0.16 g / 100 g. Example 10

[0042] Weigh out 5.25g of ascorbyl palmitate (AP), 100g of liquid glycerides (40% monoglyceride, 50% diglyceride, and 10% triglyceride, with a fatty acid composition of 5.1% saturated fatty acids, 1.8% oleic acid, 81.7% linoleic acid, and 11.4% linolenic acid), and 5g of rapeseed diglyceride oil (55% diglyceride and 45% triglyceride, with a fatty acid composition of 9.1% saturated fatty acids, 63.6% oleic acid, 18.7% linoleic acid, and 8.6% linolenic acid). The liquid glycerides and rapeseed diglyceride oil are blended to obtain a liquid edible oil carrier, with a blending ratio of 20:1. Place all the above materials together in a sealed reactor, introduce nitrogen gas to replace the air, and start stirring under nitrogen protection. Control the stirring temperature at 100℃ and continue stirring until the AP is completely dissolved, obtaining a homogeneous, transparent, light yellow liquid with good fluidity. The liquid was dispensed into brown glass bottles under a nitrogen flow, sealed after nitrogen purging, and the AP content in the resulting product was 5% of the mass of the liquid edible oil carrier. Physicochemical tests were performed on the resulting product, and the results showed that the product contained 0.5% moisture, 4.1% free glycerol, 3.0 mg / g acid value (calculated as KOH), 4.2% soap content (calculated as sodium oleate), 2.5% free fatty acid content, a freezing point of 11℃, a viscosity of 260 mPa·s at 25℃, and a peroxide value of 0.16 g / 100 g. Example 11

[0043] Weigh out 5.5g of ascorbyl palmitate (AP), 100g of liquid glycerides (40% monoglyceride, 50% diglyceride, and 10% triglyceride, with a fatty acid composition of 5.1% saturated fatty acids, 1.8% oleic acid, 81.7% linoleic acid, and 11.4% linolenic acid), and 10g of rapeseed diglyceride oil (55% diglyceride and 45% triglyceride, with a fatty acid composition of 9.1% saturated fatty acids, 63.6% oleic acid, 18.7% linoleic acid, and 8.6% linolenic acid). The liquid glycerides and rapeseed diglyceride oil are blended to obtain a liquid edible oil carrier, with a blending ratio of 10:1. Place all the above materials together in a sealed reactor, introduce nitrogen gas to replace the air, and start stirring under nitrogen protection. Control the stirring temperature at 90℃ and continue stirring until the AP is completely dissolved, obtaining a homogeneous, transparent, light yellow liquid with good fluidity. The liquid was dispensed into brown glass bottles under a nitrogen flow, sealed after nitrogen purging, and the AP content in the resulting product was 5% of the mass of the liquid edible oil carrier. Physicochemical tests were performed on the resulting product, and the results showed that the product contained 0.5% moisture, 4.0% free glycerol, 2.9 mg / g acid value (calculated as KOH), 4.1% soap content (calculated as sodium oleate), 2.4% free fatty acid content, a freezing point of 10℃, a viscosity of 230 mPa·s at 25℃, and a peroxide value of 0.15 g / 100 g. Example 12

[0044] Weigh out 5.25g of ascorbyl palmitate (AP), 100g of liquid glycerides (40% monoglyceride, 50% diglyceride, and 10% triglyceride, with a fatty acid composition of 5.1% saturated fatty acids, 1.8% oleic acid, 81.7% linoleic acid, and 11.4% linolenic acid), and 5g of medium- and long-chain triglyceride oil (5.7% medium-chain triglycerides, 81.8% medium- and long-chain triglycerides, and 12.5% ​​long-chain triglycerides, with a fatty acid composition of 46.6% saturated fatty acids, 46.7% oleic acid, and 6.7% linoleic acid). The liquid glycerides and medium- and long-chain triglyceride oil are blended to obtain a liquid edible oil carrier, with a blending ratio of 20:1. Place all the above materials together in a sealed reactor, introduce nitrogen gas into the reactor to replace the air, and start stirring under nitrogen protection. The stirring temperature was controlled at 90℃, and stirring was continued until AP was completely dissolved, resulting in a homogeneous, transparent, light yellow liquid with good fluidity. The liquid was dispensed into brown glass bottles under a nitrogen flow, sealed after nitrogen purging, and the AP content in the resulting product was 5% of the mass of the liquid edible oil carrier. Physicochemical indicators of the resulting product were tested, and the results showed that the product had a moisture content of 0.5%, a free glycerol content of 4.1%, an acid value (calculated as KOH) of 2.9 mg / g, a saponin content (calculated as sodium oleate) of 4.2%, a free fatty acid content of 2.4%, a freezing point of 12℃, a viscosity of 250 mPa·s at 25℃, and a peroxide value of 0.15 g / 100 g. Example 13

[0045] Weigh out 5.5g of ascorbyl palmitate (AP), 100g of liquid glycerides (40% monoglyceride, 50% diglyceride, and 10% triglyceride, with a fatty acid composition of 5.1% saturated fatty acids, 1.8% oleic acid, 81.7% linoleic acid, and 11.4% linolenic acid), and 10g of medium- and long-chain triglyceride oil (5.7% medium-chain triglycerides, 81.8% medium- and long-chain triglycerides, and 12.5% ​​long-chain triglycerides, with a fatty acid composition of 46.6% saturated fatty acids, 46.7% oleic acid, and 6.7% linoleic acid). The liquid glycerides and medium- and long-chain triglyceride oil are blended to obtain a liquid edible oil carrier, with a blending ratio of 10:1. Place all the above materials together in a sealed reactor, introduce nitrogen gas into the reactor to replace the air, and start stirring under nitrogen protection. The stirring temperature was controlled at 80℃, and stirring was continued until AP was completely dissolved, resulting in a homogeneous, transparent, light yellow liquid with good fluidity. The liquid was dispensed into brown glass bottles under a nitrogen flow, sealed after nitrogen purging, and the AP content in the resulting product was 5% of the mass of the liquid edible oil carrier. Physicochemical indicators of the resulting product were tested, and the results showed that the product contained 0.5% moisture, 4.0% free glycerol, 2.8 mg / g acid value (based on KOH), 4.1% soap content (based on sodium oleate), 2.3% free fatty acid content, a freezing point of 13℃, a viscosity of 240 mPa·s at 25℃, and a peroxide value of 0.14 g / 100 g. Example 14

[0046] Weigh out 5.5g of ascorbyl palmitate (AP), 100g of liquid glycerides (40% monoglyceride, 50% diglyceride, 10% triglyceride, with a fatty acid composition of 5.1% saturated fatty acids, 1.8% oleic acid, 81.7% linoleic acid, and 11.4% linolenic acid), and 10g of medium- and long-chain triglyceride oil (5.7% medium-chain triglycerides, 81.8% medium- and long-chain triglycerides, and 12.5% ​​long-chain triglycerides, with a fatty acid composition of 46.6% saturated fatty acids, 46.7% oleic acid, and 6.7% linoleic acid). The liquid glycerides and medium- and long-chain triglyceride oil are blended to obtain a liquid edible oil carrier, with a blending ratio of 10:1. Place all the above materials together in a sealed reactor, introduce nitrogen gas into the reactor to replace the air, and start stirring under nitrogen protection. The stirring temperature was controlled at 100℃, and stirring was continued until AP was completely dissolved, resulting in a homogeneous, transparent, light yellow liquid with good fluidity. The liquid was dispensed into brown glass bottles under a nitrogen flow, sealed after nitrogen purging, and the AP content in the resulting product was 5% of the mass of the liquid edible oil carrier. Physicochemical indicators of the resulting product were tested, and the results showed that the product contained 0.5% moisture, 4.1% free glycerol, 2.9 mg / g acid value (based on KOH), 4.2% soap content (based on sodium oleate), 2.4% free fatty acid content, a freezing point of 13℃, a viscosity of 250 mPa·s at 25℃, and a peroxide value of 0.16 g / 100 g. Example 15

[0047] The liquid antioxidant prepared in Example 1 was premixed with tocopherol (vitamin E) at a mass ratio of AP:tocopherol of 1:1, and then added to rapeseed oil at a concentration of 300 mg / kg based on the total antioxidant. Accelerated oxidation tests showed that the antioxidant effect of this composite system was significantly better than that of AP or tocopherol alone, exhibiting a significant synergistic effect. Example 16

[0048] The liquid antioxidant prepared in Example 2 was premixed with tea polyphenol palmitate at a mass ratio of AP:tea polyphenol palmitate of 1:3, and then added to rapeseed oil at a concentration of 800 mg / kg based on the total antioxidant. Accelerated oxidation tests showed that the antioxidant effect of this composite system was significantly better than that of AP or tea polyphenol palmitate alone, exhibiting a significant synergistic effect. Example 17

[0049] The liquid antioxidant prepared in Example 3 was premixed with tea polyphenols at a mass ratio of AP:tea polyphenols of 1:3, and then added to rapeseed oil at a concentration of 400 mg / kg of total antioxidants. Accelerated oxidation tests showed that the antioxidant effect of this composite system was significantly better than that of AP or tea polyphenols alone, exhibiting a significant synergistic effect. Example 18

[0050] The liquid antioxidant prepared in Example 3 was premixed with tea polyphenols at a mass ratio of AP:tea polyphenols of 1:7, and then added to soybean oil at a concentration of 600 mg / kg of total antioxidant. Accelerated oxidation tests showed that the antioxidant effect of this composite system was significantly better than that of AP or tea polyphenols alone, exhibiting a significant synergistic effect. Example 19

[0051] The liquid antioxidant prepared in Example 2 was premixed with tea polyphenols at a mass ratio of AP:rosemary extract of 1:2, and then added to rapeseed oil at a concentration of 600 mg / kg of total antioxidant. Accelerated oxidation tests showed that the antioxidant effect of this composite system was significantly better than that of AP or rosemary extract alone, exhibiting a significant synergistic effect. Example 20

[0052] The liquid antioxidant prepared in Example 1 was added to refined rapeseed oil at a concentration of 200 mg / kg (based on AP). Rapeseed oil with an equal amount of AP powder (pre-heated and dissolved) was used as a control for the traditional method. The results showed that the traditional AP powder required high temperature to dissolve and had a slow dissolution rate. The liquid antioxidant of this invention does not require high temperature and can be quickly dissolved by simple stirring at room temperature. It is easy to operate and has high dissolution efficiency. Example 21

[0053] The liquid antioxidant prepared in Example 2 was added to refined soybean oil at a concentration of 200 mg / kg (AP). Soybean oil without any added antioxidant served as a blank control, while soybean oil with an equal amount of AP powder (pre-dissolved by heating) was used as a control using the conventional method. All oil samples were subjected to accelerated oxidation testing (Schaal oven method) in a constant temperature oven at (60±1)℃, and their peroxide value (POV) was measured periodically. The results showed that the POV of the oil sample with the added liquid antioxidant of this invention increased significantly slower than that of the blank control, and compared with the group with direct powder addition, it showed a lower POV value in the early stage of oxidation, indicating that it is more uniformly dispersed and has a faster onset of action. Example 22

[0054] In the ingredient preparation stage of fried instant noodle cakes, the liquid antioxidant prepared in Example 2 was directly added to the palm oil used for frying (150 mg / kg of total oil content, calculated as AP), stirred evenly, and then used for frying the noodle cakes. Noodle cakes fried in palm oil without added antioxidants were used as a control. The finished product was stored at 37°C. The acid value and peroxide value of the noodle cakes were periodically tested. The results showed that the increase in oil oxidation indicators during storage was significantly lower in the noodle cakes containing the product of this invention compared to the control group, and the shelf life was significantly extended. Example 23

[0055] The liquid antioxidant prepared in Example 2 was diluted with a small amount of water to prepare an oil-in-water emulsion. Fresh walnut kernels were immersed in the emulsion for a short time, drained, and air-dried at 50°C. Walnut kernels treated with water alone served as a control. The treated walnut kernels were subjected to accelerated oxidation at 40°C and 60% relative humidity. Sensory evaluation (for rancidity) and POV were measured periodically. The results showed that the walnut kernels treated with the coating of the product of this invention developed a noticeable rancidity more than twice as late as the control group, and the POV value remained at a low level. Example 24

[0056] The liquid antioxidant from Example 2 was added after the butter was melted but before homogenization, at an amount of 100 mg / kg butter (AP). After thorough mixing, the mixture was cooled and shaped. It was then stored together with a blank butter sample at 4°C and at room temperature (25°C). The degree of oxidation was evaluated by measuring the thiobarbituric acid value (TBARS). The results showed that the butter containing the product of this invention had significantly lower TBARS values ​​than the blank sample at different storage temperatures, indicating better flavor retention. Example 25

[0057] In the seasoning and marinating process of pork jerky, the liquid antioxidant prepared in Example 3 (0.02% of the raw meat weight based on AP) was added to the minced meat along with seasonings such as sugar, salt, and soy sauce, and stirred thoroughly. Pork jerky without added antioxidants served as a control. After baking, the product was stored at room temperature away from light. The fat oxidation value was measured periodically. The results showed that pork jerky with the product of this invention exhibited a slower oxidation rate and a longer shelf life. Example 26

[0058] In preparing the mayonnaise-type salad dressing, the liquid antioxidant prepared in Example 3 (calculated as AP, accounting for 100 mg / kg of total oil content) was directly added to the vegetable oil phase, followed by emulsification. The finished product was stored at 4°C. Sensory evaluation and oxidation index testing showed that the salad dressing containing the product of this invention exhibited improved flavor stability and shelf life. Example 27

[0059] Liquid antioxidants with different AP contents prepared in Examples 1 and 2 were stored at 4°C, 25°C, and 40°C, respectively, in the dark for 6 months. Samples were taken monthly to observe their appearance and to determine the AP content (using HPLC). The results showed that all samples remained clear and transparent within 6 months, without layering, crystallization, or discoloration, and the AP content retention rate was above 98%, demonstrating that the product of this invention has excellent storage stability. Comparative Example 1

[0060] 5g of ascorbyl palmitate (AP) and 100g of refined rapeseed oil (containing 0.6% diglycerides and 99.6% triglycerides, with a fatty acid composition of 4.8% saturated fatty acids, 59.2% oleic acid, 22.4% linoleic acid, and 7.9% linolenic acid) were stirred and dissolved under nitrogen protection at 100°C to obtain a homogeneous, transparent, light yellow liquid. This liquid turned into a paste after standing and cooling for 1 hour. Comparative Example 2

[0061] 5g of ascorbyl palmitate (AP) and 100g of rapeseed diglyceride oil (40% diglyceride, 60% triglyceride, with a fatty acid composition of 8.9% saturated fatty acids, 62.4% oleic acid, 19.3% linoleic acid, and 9.4% linolenic acid) were stirred and dissolved under nitrogen protection at 100°C to obtain a homogeneous, transparent, light yellow liquid. After standing and cooling for 1 hour, the liquid turned into a paste. Comparative Example 3

[0062] 1g of ascorbyl palmitate (AP) and 100g of rapeseed diglyceride oil (diglyceride content 55%, triglyceride content 45%, fatty acid composition 9.1% saturated fatty acids, 63.6% oleic acid, 18.7% linoleic acid, and 8.6% linolenic acid) were dissolved under nitrogen protection and stirred at 100°C to obtain a homogeneous, transparent, light yellow liquid. After standing and cooling for 24 hours, a precipitate was formed in the liquid. Comparative Example 4

[0063] 1g of ascorbyl palmitate (AP) and 100g of corn diglyceride oil (50% diglyceride and 50% triglyceride, with a fatty acid composition of 15.5% saturated fatty acids, 27.4% oleic acid, 56.1% linoleic acid and 1.0% linolenic acid) were dissolved under nitrogen protection and stirred at 110°C to obtain a homogeneous, transparent, light yellow liquid. After standing and cooling for 12 hours, flocculent precipitate was formed in the liquid. Comparative Example 5

[0064] 1g of ascorbyl palmitate (AP) and 100g of medium- and long-chain triglyceride oil (5.7% medium-chain triglycerides, 81.8% medium- and long-chain triglycerides, and 12.5% ​​long-chain triglycerides, with a fatty acid composition of 46.6% saturated fatty acids, 46.7% oleic acid, and 6.7% linoleic acid) were dissolved under nitrogen protection and stirred at 100°C to obtain a homogeneous, transparent, light yellow liquid. After standing and cooling for 12 hours, a flocculent precipitate was formed in the liquid. Comparative Example 6

[0065] 5g of tea polyphenol palmitate and 100g of refined rapeseed oil (containing 0.6% diglyceride and 99.6% triglyceride, with a fatty acid composition of 4.8% saturated fatty acids, 59.2% oleic acid, 22.4% linoleic acid, and 7.9% linolenic acid) were stirred and dissolved under nitrogen protection at 110°C to obtain a homogeneous, transparent, reddish-brown liquid. This liquid turned into a paste after standing and cooling. Comparative Example 7

[0066] 1g of tea polyphenol palmitate and 100g of rapeseed diglyceride oil (diglyceride content 40%, triglyceride content 60%, fatty acid composition 8.9% saturated fatty acids, 62.4% oleic acid, 19.3% linoleic acid, and 9.4% linolenic acid) were dissolved under nitrogen protection and stirred at 80°C to obtain a homogeneous, transparent, reddish-brown liquid. After standing and cooling for 1 hour, the liquid turned into a paste. Comparative Example 8

[0067] Weigh 10 g of ascorbyl palmitate (AP) and 100 g of liquid glycerides (40% monoglyceride, 50% diglyceride, and 10% triglyceride, with a fatty acid composition of 5.1% saturated fatty acids, 1.8% oleic acid, 81.7% linoleic acid, and 11.4% linolenic acid). Place both in a sealed reactor. Start stirring and maintain the temperature at 100°C, stirring continuously until the AP is completely dissolved, yielding a homogeneous, transparent, reddish-brown liquid. Dispense the liquid into brown glass bottles and seal them. The resulting product contains 10% AP. After 72 hours of storage, a precipitate forms at the bottom of the glass bottle.

[0068] Figure 1The images show the appearance of AP-liquid glycerol ester systems with different AP additions after being heated and stirred to dissolve under nitrogen protection and then allowed to stand for 48 hours. From left to right, the mass fractions of AP in the final mixture are 0%, 1%, 2.0%, 4.8%, and 9.1%, which approximately correspond to AP additions of 0%, 1%, 2%, 5%, and 10% of the mass of liquid glycerol ester, respectively. The 9.1% sample corresponds to the product composition of "10 g AP, 100 g liquid glycerol ester" in Example 1. The specific preparation process is as follows: 100 g of liquid glycerol ester was weighed and added to different masses of ascorbyl palmitate (AP), and both were placed together in a sealed reaction vessel. Nitrogen gas was introduced into the vessel to replace the air, and stirring was started under nitrogen protection. The temperature was controlled at 100°C, and stirring continued until the AP was completely dissolved, resulting in a homogeneous, transparent, light yellow liquid. The mixture was then cooled under nitrogen protection and dispensed into brown glass bottles, sealed with nitrogen, and allowed to stand at room temperature for 48 hours before observing its appearance. The results showed that no obvious stratification, precipitation or exudation occurred in the systems with different AP addition amounts, indicating that the liquid glyceride system can serve as a good dissolving / dispersing carrier for AP and can maintain good appearance stability even at higher AP addition amounts.

[0069] Figure 2 This figure illustrates the effect of different oil carriers on the solubility / dispersion stability of AP under the same AP addition amount. As shown in the figure, each group had 5% AP added based on the mass of the oil carrier, resulting in an AP mass fraction of approximately 4.8% in the final mixture. From left to right, the oil carriers are liquid glycerol ester, refined rapeseed oil, 40% rapeseed diglyceride oil, 55% rapeseed diglyceride oil, and medium- and long-chain triglyceride oil. This figure represents the results of an independent oil carrier screening experiment and does not directly correspond to the AP addition amounts in the examples and comparative examples 1–5. All samples were subjected to the same nitrogen protection, heating and stirring treatment, and then observed after standing. The results show that the liquid glycerol ester group was uniform and transparent in appearance, with no obvious layering, precipitation, or AP separation, indicating that liquid glycerol ester has better AP solubility / dispersion carrying capacity.

[0070] Table 1. Solubility of solid antioxidants in Examples 1-8 and Comparative Examples 1-7.

[0071]

[0072] The data in the table show that in Examples 1-13, when liquid glycerides were used as the oil carrier, the solid antioxidants remained stable after heating and dissolving, and no obvious stratification, precipitation, or separation occurred after standing, maintaining good fluidity. In Comparative Examples 1-7, when other oil carriers were used, the systems easily became pasty, precipitated, or formed flocculent precipitates after cooling or standing. This indicates that liquid glycerides have a good dissolving and stabilizing effect on solid antioxidants, effectively improving their storage stability in oil systems.

[0073] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A food-grade liquid antioxidant, characterized in that, The food-grade liquid antioxidant is composed of a solid antioxidant uniformly dispersed in a liquid edible oil carrier; The amount of the solid antioxidant added is 0.5% to 15% of the mass of the liquid edible oil carrier; The liquid edible oil carrier is a liquid glyceride, or a mixture of liquid glyceride with one or more of diglyceride oil, medium-chain triglyceride oil, and vegetable oil in a mass ratio of 5:1 to 20:

1. The liquid glyceride is composed of monoglycerides, diglycerides, and triglycerides. Based on the total mass of the liquid glyceride as 100%, the mass percentage of monoglycerides is 30% to 60%, the mass percentage of diglycerides is 30% to 50%, and the mass percentage of triglycerides is 10% to 30%, and the sum of the mass percentages of the three is 100%.

2. The food-grade liquid antioxidant according to claim 1, characterized in that, The solid antioxidant is selected from one or more of tea polyphenols, rosemary extract, propyl gallate, ascorbyl palmitate, and tea polyphenol palmitate.

3. The food-grade liquid antioxidant according to claim 1, characterized in that, Based on the total mass of fatty acids constituting monoglycerides, diglycerides, and triglycerides in the liquid glycerides as 100%, the mass percentage of saturated fatty acids is <10%, and the mass percentage of unsaturated fatty acids is ≥90%; specifically, it is any combination of palmitic acid, oleic acid, linoleic acid, and linolenic acid.

4. The food-grade liquid antioxidant according to claim 1, characterized in that, The food-grade liquid antioxidant is pale yellow or light brown, a viscous liquid or paste, and its physicochemical properties must meet the following requirements: moisture ≤1.0%, free glycerol ≤7.0%, acid value (calculated as KOH) ≤4.0 mg / g, soap content (calculated as sodium oleate) ≤6.0%, free fatty acids ≤3.0 mg / g, freezing point <15℃, viscosity 20-500 mPa·s, and peroxide value <0.25 g / 100g.

5. A method for preparing a food-grade liquid antioxidant as described in claim 1, characterized in that, The method is specifically as follows: Under inert gas protection, solid antioxidants are stirred and mixed with liquid edible oil carriers to uniformly disperse them in the liquid edible oil carriers, resulting in a homogeneous liquid mixture, which is the food-grade liquid antioxidant. Alternatively, the solid antioxidant is first dissolved in ethanol to form a first solution; then, under the protection of an inert gas, the first solution is stirred and mixed with a liquid edible oil carrier to fully dissolve and disperse the solid antioxidant in the liquid edible oil carrier, resulting in a homogeneous liquid mixture. The ethanol is then removed to obtain the food-grade liquid antioxidant.

6. The method according to claim 5, characterized in that, The inert gas is one of nitrogen, argon, and helium; The mixing temperature is 30~100℃.

7. The method according to claim 5, characterized in that, The method for removing ethanol is vacuum desolventizing, with a vacuum degree of -0.05MPa to -0.1MPa and a temperature of 40℃ to 70℃.

8. The use of a food-grade liquid antioxidant as described in any one of claims 1-4 or a food-grade liquid antioxidant prepared by the method described in any one of claims 5-7 in oils or oil-containing foods.

9. The application according to claim 8, characterized in that, The food-grade liquid antioxidant can be used alone or in combination with one or more of tocopherol, tea polyphenols, rosemary extract, propyl gallate, and tea polyphenol palmitate.

10. The application according to claim 8, characterized in that, The oils and fats include soybean oil, rapeseed oil, peanut oil, olive oil, palm oil, lard, butter, and blends thereof; The oily foods include baked goods, fried foods, nut products, mayonnaise, salad dressing, meat products, and instant noodles.

Images