Method for reducing zearalenone in maize germ and application

Abstract

The invention relates to the technical field of corn oil processing, in particular to a method for reducing zearalenone in corn germs and application. The method comprises the following steps: soaking corn germs in a chlorine dioxide aqueous solution; the concentration of the chlorine dioxide aqueous solution is 1000-2000 mg / L, and the solid-to-liquid ratio of the corn germ to the chlorine dioxide aqueous solution is 1: 10-1: 20 g / mL. According to the method, zearalenone in the corn germs can be effectively degraded, the zearalenone degradation efficiency of chlorine dioxide is improved, the challenge of removing ZEN from the corn oil and the risk of quality deterioration are avoided, meanwhile, the adverse effect on the quality of the corn oil can be greatly reduced, and the overall quality of the corn oil is effectively improved.

Description

Technical Field

[0001] This invention relates to the field of corn oil processing technology, and in particular to a method and application for reducing zearalenone in corn germ. Background Technology

[0002] Zearalenone (ZEN) is one of the most widely distributed mycotoxins, primarily produced by Fusarium species. Studies have shown that ZEN has various toxicological effects, including immunotoxicity, genotoxicity, carcinogenicity, and teratogenicity. ZEN contamination is prevalent in various grains, such as corn, wheat, and soybeans.

[0003] Corn germ is extremely high in fat, rich in protein, and has a dense structure. ZEN, as a fat-soluble toxin, is more likely to accumulate in the germ and is encapsulated by fat and protein, making it difficult to remove efficiently using traditional physical or chemical methods, which can easily damage the nutritional and functional components of the germ. To date, no effective, safe, and cost-efficient method has been established to remove ZEN from corn germ oil.

[0004] Due to the challenges of removing ZEN from corn germ oil and the risk of quality deterioration caused by traditional methods of processing corn oil, there is an urgent need to design novel methods for degrading ZEN in raw material corn germ in order to reduce the adverse effects on oil quality. Summary of the Invention

[0005] To address the aforementioned technical problems, this invention provides a method for reducing zearalenone in corn oil. This method effectively degrades zearalenone in corn oil, overcoming the challenges and risks of ZEN removal from corn germ oil, effectively reducing ZEN levels in corn oil, significantly minimizing adverse effects on corn oil quality, and effectively improving the overall quality of corn oil.

[0006] Firstly, this invention provides a method for reducing zearalenone in corn germ, comprising: soaking corn germ in a chlorine dioxide aqueous solution; wherein the concentration of the chlorine dioxide aqueous solution is 1000~2000 mg / L, and the solid-liquid ratio of the corn germ to the chlorine dioxide aqueous solution is 1:10~1:20 g / mL. This invention, targeting corn germ, utilizes a soaking reaction with a chlorine dioxide aqueous solution of a specific solid-liquid ratio and concentration to better treat the corn germ, improving the efficiency and overall effect of chlorine dioxide degradation of zearalenone. This addresses the challenge of removing ZEN from corn germ oil and the risk of quality deterioration, thus improving the overall quality of the obtained corn germ oil.

[0007] Preferably, the concentration of the chlorine dioxide aqueous solution is 1000~1500 mg / L, such as 1000 mg / L, 1200 mg / L, 1300 mg / L, 1400 mg / L, 1500 mg / L, etc. The present invention uses a chlorine dioxide aqueous solution of a preferred concentration to achieve a better ZEN degradation rate efficiently, and combined with other conditions, it can further improve the quality of corn germ oil in subsequent treatments.

[0008] Preferably, the solid-liquid ratio of the corn germ to the chlorine dioxide aqueous solution is 1:10~15 g / mL, for example 1:10 g / mL, 1:11 g / mL, 1:12 g / mL, 1:13 g / mL, 1:14 g / mL, 1:15 g / mL, etc. A better treatment effect is achieved when the preferred ratio range is reached.

[0009] Preferably, the pH value of the soaking is 1 to 3, such as 1, 1.5, 2, 3, etc. More preferably, the pH value of the soaking is 1 to 2. Treatment at the preferred pH value yields better results.

[0010] Preferably, the soaking temperature is 4~60℃ and the soaking time is 0.5~2 h.

[0011] Further preferably, the soaking temperature is 20~40℃, such as 20℃, 25℃, 30℃, 35℃, 40℃, etc., and the soaking time is 1~1.5 h, such as 1 h, 1.2 h, 1.3 h, 1.4 h, 1.5 h, etc.

[0012] Further preferably, the soaking reaction is carried out under sealed conditions.

[0013] Further optimization involves using hydrochloric acid and sodium hydroxide solution for pH adjustment.

[0014] Further preferably, the soaking process also includes washing and drying steps.

[0015] Secondly, the present invention provides the application of the method for reducing zearalenone in corn germ in the preparation of corn oil.

[0016] The method of this invention can effectively reduce the ZEN level in corn oil raw materials, reduce the risk of mycotoxins, and improve food safety and processing efficiency. At the same time, it has little impact on the quality of corn oil and improves the antioxidant capacity of corn germ oil. Furthermore, it retains more of the levels of fatty acids such as palmitic acid, stearic acid, oleic acid, linoleic acid, and arachidic acid, as well as phytosterols such as linolenic acid sterol, stigmasterol, and β-sitosterol in corn oil. This provides a high-quality, efficient, economical, and easy-to-operate new approach for the detoxification of mycotoxins in corn oil.

[0017] The beneficial effects of this invention are at least as follows: The method provided by this invention, by employing a specific solid-liquid ratio of corn germ to chlorine dioxide aqueous solution, the concentration of chlorine dioxide aqueous solution, and the combined effects of soaking pH, temperature, and time, can more effectively and efficiently degrade zearalenone in corn germ while better ensuring the overall quality of corn oil. It solves the challenge of removing ZEN from corn germ oil and the risk of quality deterioration caused by existing treatment methods. This invention degrades ZEN in raw corn germ by soaking in chlorine dioxide, which can reduce treatment time, improve the efficiency of zearalenone removal, and effectively reduce the risk of ZEN contamination in corn oil while reducing the impact of chemical detoxification on the quality of corn oil. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0019] Figure 1 The ZEN standard is a chlorine dioxide degradation product used in the embodiments of this invention.

[0020] Figure 2 This is a possible pathway for chlorine dioxide to degrade ZEN in the embodiments of the present invention.

[0021] Figure 3 This invention illustrates the degradation effect of chlorine dioxide on ZEN-spiked corn germ in an embodiment of the invention.

[0022] Figure 4 The results show the optimization of chlorine dioxide detoxification parameters in the embodiments of the present invention.

[0023] Figure 5 This illustrates the effect of chlorine dioxide concentration on the color of corn oil in an embodiment of the present invention.

[0024] Figure 6 This invention illustrates the effect of chlorine dioxide concentration on the color of corn germ oil in an embodiment of the invention. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of this invention, not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0026] The endpoints and any values ​​of the ranges disclosed in this invention are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed in this invention.

[0027] Unless otherwise specified, the techniques or conditions described in the literature of this invention shall apply, or the product instructions shall be followed. Devices, instruments, reagents, etc., whose manufacturers are not specified, are all conventional products that can be purchased from legitimate channels. All experimental reagents and raw materials involved are commercially available, and all reagents are analytical grade products.

[0028] Example 1 This embodiment provides the degradation effect of chlorine dioxide on ZEN standards, including: 1. Preparation of ZEN standard: Weigh 5 mg of ZEN standard dry powder, add 1 mL of methanol to dissolve it completely, and prepare a 5 mg / mL ZEN standard stock solution. Store at -20℃. Take out the ZEN standard stock solution and dilute it serially with methanol to prepare a 10 μg / mL ZEN standard working solution. Store it at 4℃ for later use.

[0029] 2. Preparation of chlorine dioxide: The chlorine dioxide solution was prepared according to the Chinese National Standard GB / T 26366-2021, "Hygienic Requirements for Chlorine Dioxide Disinfectants". Dilute H₂SO₄ was slowly added dropwise to the NaClO₂ solution to produce ClO₂. 2， Other impurities were removed using sodium chlorite solution. The generated ClO2 gas was passed through a constant gas flow and then introduced into pure water to prepare a standard solution. The concentration was determined using spectrophotometry.

[0030] 3. Degradation effect of different reaction times on ZEN standard: Mix the same volume of 1 mg / L chlorine dioxide solution and ZEN standard working solution, and shake and react at room temperature for different times (0, 10, 20, 30 and 60 min). The degradation effect of different reaction times on ZEN standard was measured.

[0031] 4. Degradation effect of different chlorine dioxide concentrations on ZEN standard: The same volume of chlorine dioxide solutions of different concentrations (0.1, 0.2, 0.5, 1, 2 and 5 mg / L) and ZEN standard working solution were mixed and reacted with shaking at room temperature for 0.5 h. The degradation effect of different concentrations of chlorine dioxide solutions on ZEN standard was then determined.

[0032] 5. Determination of ZEN standard: The sample solution obtained in step 3 was detected by HPLC under the following conditions: mobile phase acetonitrile:water = 7:3; flow rate 1 mL / min; column C18 (250 mm × 4.6 mm, 5 µm); excitation wavelength 274 nm, detection wavelength 440 nm; column temperature 30℃; injection volume 20 µL.

[0033] The results are as follows Figure 1 As shown, reaction time had no significant effect on the degradation effect. The degradation rate increased slowly with increasing time, and there was no significant difference between the degradation rate at 60 min and those at 20 and 30 min, remaining between 50-60%. However, the concentration of chlorine dioxide had a significant impact on the degradation effect. At a concentration of 5 mg / L, all ZEN was degraded.

[0034] Example 2 This embodiment provides the identification of degradation products of ZEN by chlorine dioxide, including: 1. Sample Preparation: Degradation samples with chlorine dioxide concentrations of 3 mg / L and 5 mg / L from Example 1 were selected, along with negative and positive controls. The samples were passed through a 0.22 µm filter and placed into liquid chromatography vials for analysis.

[0035] 2. ZEN degradation products were determined using an Agilent 1290 Infinity II ultra-high performance liquid chromatography (UHPLC) system and a Q ExactiveFocus Orbitrap LC-MS / MS system (Thermo Scientific). The detection conditions were as follows: the mobile phase was (A) 0.1% formic acid aqueous solution (v / v) and (B) acetonitrile. The gradient elution conditions were as follows: 0–0.1 min 95% A and 5% B, 0.1–12 min 5% B, 12–15 min 55% B, and 15–17 min 100% B. The flow rate was 0.3 mL / min. The column temperature was 30 °C. The injection volume was 10 μL. Electrospray ionization (ESI) was used for mass spectrometry detection. Mass spectra were acquired in a full scan analysis at m / z 200–1000. All spectral data were processed using Xcalibur software.

[0036] The results are as follows Figure 2As shown, the mass spectrometry results indicate that the main differentially expressed compounds have m / z values ​​of 279.1242, 319.1199, 215.0100, 337.1306, and 381.0759. Based on the oxidation mechanism, this invention proposes for the first time a ClO2 degradation pathway for ZEN. The degradation pathway begins with ClO2 attacking the most reactive olefin double bond in ZEN, leading to oxidative cleavage, subsequently forming carbonyl oxides and carbonyl compounds. The main toxicity of ZEN can be attributed to its intact molecular structure; the phenolic hydroxyl group and the intact macrocyclic lactone structure are key components maintaining its toxicity. When the C8-C9 double bond is oxidized and the lactone ring is cleaved, the spatial conformation of ZEN changes significantly, and its toxicity decreases or is even lost.

[0037] Example 3 This embodiment provides information on the effects of chlorine dioxide on the total bacterial count and mold count in corn germ, including: 1. Chlorine dioxide treatment: Take 100 g of corn germ (ZEN content 4199.45 μg / kg), add chlorine dioxide solutions of different concentrations (0, 1000, 2000 and 3000 mg / L) at a solid-liquid ratio of 1:10, seal, and let stand at room temperature for 1 h. After the reaction is complete, wash the corn germ and dry it.

[0038] 2. Total bacterial count: Weigh 10 g of the above corn germ sample and place it in 100 mL of sterile phosphate buffer. Homogenize for 1 min. Perform serial dilutions on the sample, and spread 100 μL of the diluted sample solution evenly on LB medium. Incubate at 37°C and count the bacteria.

[0039] 3. Mold Count: Weigh 10 g of the above corn germ sample and place it in 100 mL of sterile phosphate buffer. Homogenize for 1 min. Perform serial dilutions on the sample, and evenly spread 100 μL of the diluted sample solution onto PDA medium. Incubate at 28°C and count the fungi.

[0040] The results are shown in Table 1. The total bacterial count and mold count of corn germ without chlorine dioxide treatment were 1.7 × 10⁻⁶. 3 and 2.3×10 2 CFU / g. No bacteria or fungi were detected after treating corn germ with three concentrations of chlorine dioxide, indicating that chlorine dioxide has a significant sterilization effect.

[0041] Table 1. Effects of different concentrations of chlorine dioxide on total bacterial count and mold count in maize germ.

[0042] Example 4 This embodiment provides the removal effect of chlorine dioxide on ZEN-spiked corn germ, including: 1. Preparation of ZEN standard: Weigh 5 mg of ZEN standard dry powder, add 1 mL of methanol to dissolve it completely, and prepare a 5 mg / mL ZEN standard stock solution. Store at -20℃. Take out the ZEN standard stock solution and dilute it serially with methanol to prepare a 100 μg / mL ZEN standard working solution. Store it at 4℃ for later use.

[0043] 2. Preparation of spiked samples: Weigh 50 g of corn germ, add ZEN standard working solution diluted with water, mix thoroughly, so that the ZEN toxin content in the final corn germ is 5 μg / g.

[0044] 3. Chlorine dioxide treatment: Take the above-mentioned spiked corn germ and add chlorine dioxide solutions of different concentrations (0, 1000, 2000, and 3000 mg / L) at a solid-liquid ratio of 1:10. Seal the solution and let it stand at room temperature for 1 hour. After the reaction is complete, wash the corn germ and dry it. Grind the corn germ into powder using a grinder and pass it through a 20-mesh sieve.

[0045] 4. Determination of ZEN content: Weigh 10 g of treated corn germ powder, add 10 times the volume of 70% acetonitrile, and shake at 200 rpm for 30 min. Then centrifuge and filter with rapid qualitative filter paper. Then, add 10 mL of the filtrate to 40 mL of 0.01 mol / L PBST solution, mix well, and filter again with glass fiber filter paper. Take 25 mL of the filtrate and pass it through a ZEN immunoaffinity column, adjusting the flow rate to 1-2 drops / s until the liquid completely passes through the immunoaffinity column; wash the affinity column with 10 mL of pure water at a flow rate of 1-2 drops / s; finally, rinse the affinity column with 1 mL of anhydrous methanol at a flow rate of 1-2 drops / s, collect this eluent in a 1.5 mL centrifuge tube, filter through a 0.22 µm organic phase nylon membrane, and transfer to a 2 mL chromatographic vial to obtain the sample solution. Then, detect ZEN using the method in Example 1.

[0046] The results are as follows Figure 3 As shown, chlorine dioxide has a significant effect on the degradation of ZEN in corn germ with added toxins. At a concentration of 1000 mg / L, the degradation rate reached 91.83%, and the ZEN degradation rate increased with increasing chlorine dioxide concentration.

[0047] Example 5 This embodiment provides a method for removing ZEN from corn germ by chlorine dioxide degradation, including: 1. Solid-liquid ratio optimization: Take 100 g of corn germ (ZEN content 4199.45 μg / kg), add 1000 mg / L chlorine dioxide solution at a certain solid-liquid ratio (1:5, 1:10, 1:15, and 1:20), seal, and let stand at room temperature for 1 h. After the reaction is complete, wash the corn germ and dry it. Grind the corn germ into powder using a pulverizer and pass it through a 20-mesh sieve.

[0048] The results are as follows Figure 4 As shown in Figure A, increasing the solid-liquid ratio can improve the degradation efficiency of ZEN. However, when the ratio exceeds 1:10, no further enhancement of degradation was observed, thus determining this to be the optimal ratio.

[0049] 2. Optimization of reaction concentration: Take 100 g of corn germ (ZEN content 4199.45 μg / kg), add different concentrations of chlorine dioxide solution (0, 1000, 2000, and 3000 mg / L) at a solid-liquid ratio of 1:10, seal, and let stand at room temperature for 1 h. After the reaction is complete, wash the corn germ and dry it. Grind the corn germ into powder using a grinder and pass it through a 20-mesh sieve.

[0050] The results are as follows Figure 4 As shown in Figure B, concentration has the most significant impact on the degradation of ZEN. The degradation rate increases significantly with increasing chlorine dioxide solution concentration. However, the increase in degradation rate slows down when the concentration exceeds 2000 mg / L. At a concentration of 2000 mg / L, the degradation rate reaches 65.47%. Therefore, a concentration of 2000 mg / L is selected as the optimal condition. The difference between these results and those in Example 4 indicates that there are still certain differences between the spiked toxin sample and the natural sample. The toxin in the natural sample is more difficult to remove.

[0051] 3. Soaking Time Optimization: Take 100 g of corn germ (ZEN content 4199.45 μg / kg), add 1000 mg / L chlorine dioxide solution at a solid-liquid ratio of 1:10, seal, and let stand at room temperature for different times (0.5, 1, 1.5, and 2 h). After the reaction is complete, wash the corn germ and dry it. Grind the corn germ into powder using a grinder and pass it through a 20-mesh sieve.

[0052] The results are as follows Figure 4 As shown in Figure C, soaking time affects the ZEN degradation rate. Extending the soaking time increases the ZEN degradation rate. However, when the time exceeds 1 hour, the degradation rate is not significantly affected. Therefore, 1 hour is selected as the optimal condition.

[0053] 4. Optimization of soaking temperature: Take 100 g of corn germ (ZEN content 4199.45 μg / kg), add 1000 mg / L chlorine dioxide solution at a solid-liquid ratio of 1:10, seal, and let stand for 1 h at different temperatures (4℃, 20℃, 40℃, and 60℃). After the reaction is complete, wash the corn germ and dry it. Grind the corn germ into powder using a pulverizer and pass it through a 20-mesh sieve.

[0054] The results are as follows Figure 4 As shown in Figure D, the effect of different temperatures on the degradation of ZEN in corn germ by chlorine dioxide initially increases and then decreases. The degradation rate decreases above 40℃. Meanwhile, the degradation rates at 20℃ and 40℃ show no significant difference. Therefore, room temperature (20℃) was selected as the optimal condition.

[0055] 5. pH Optimization of the Reaction: Take 100 g of corn germ (ZEN content 4199.45 μg / kg), add 1000 mg / L chlorine dioxide solution at a solid-liquid ratio of 1:10, and adjust the pH to (1, 3, 5, 7, 9, and 11) with 0.1 mol / L sodium hydroxide solution or 0.1 mol / L hydrochloric acid solution. Seal and let stand at room temperature for 1 h. After the reaction is complete, wash the corn germ and dry it. Grind the corn germ into powder using a grinder and pass it through a 20-mesh sieve.

[0056] The results are as follows Figure 4 As shown in Figure E, pH significantly affects the degradation rate of ZEN. Lower pH significantly improves the degradation effect of chlorine dioxide. When the pH is greater than 5, the degradation effect decreases significantly. Since the pH of the chlorine dioxide solution itself is low, pH 1 was chosen as the optimal condition.

[0057] 6. Determination of ZEN content: Weigh 10 g of treated corn germ powder, add 10 times the volume of 70% acetonitrile, and shake at 200 rpm for 30 min. Then centrifuge and filter with rapid qualitative filter paper. Then, add 10 mL of the filtrate to 40 mL of 0.01 mol / L PBST solution, mix well, and filter again with glass fiber filter paper. Take 25 mL of the filtrate and pass it through a ZEN immunoaffinity column, adjusting the flow rate to 1-2 drops / s until the liquid completely passes through the immunoaffinity column; wash the affinity column with 10 mL of pure water at a flow rate of 1-2 drops / s; finally, rinse the affinity column with 1 mL of anhydrous methanol at a flow rate of 1-2 drops / s, collect this eluent in a 1.5 mL centrifuge tube, filter through a 0.22 µm organic phase nylon membrane, and transfer to a 2 mL chromatographic vial to obtain the sample solution. Then, detect ZEN using the method in Example 1.

[0058] Example 6 This embodiment describes the effect of chlorine dioxide degradation of ZEN in corn oil on the quality of corn oil. Crude corn oil and refined corn oil were selected as experimental subjects. 45 g of oil sample was weighed, and 1000 mg / L of chlorine dioxide solution was added at a ratio of 9:1 (corn oil: chlorine dioxide solution). The mixture was stirred at 400 r / min for 1 h. After stirring, the mixture was centrifuged at 8000 r / min for 20 min at 4℃, and the samples were observed visually and smelled.

[0059] The results are as follows Figure 5 As shown, chlorine dioxide significantly alters the color of crude and refined corn oil, reducing its depth and increasing its brightness. Furthermore, in terms of odor, chlorine dioxide-treated oil samples exhibit not only the characteristic smell of corn oil but also a pungent odor, imparting an unpleasant flavor. Directly treating ZEN in corn oil with chlorine dioxide has a significant impact on its quality.

[0060] Example 7 The effects of different chlorine dioxide concentrations on the quality of corn germ oil were investigated, including: 1. Extraction of corn germ oil: Weigh 100 g of corn germ treated in Example 4 (crushed and passed through a 20-mesh sieve), and add petroleum ether at a certain ratio (8:1, v / w). Shake and extract for 2 h, repeat three times, combine the three extraction solutions, and then filter through filter paper. Evaporate all petroleum ether to obtain corn germ oil.

[0061] 2. Effect on the color of corn germ oil: 20 mL of extracted corn germ oil was poured into a 9 cm petri dish, and the color of the oil was measured using an electronic eye. Each sample was fixed at the same location against a white background, and the color of five representative areas or points was measured and recorded. L , a and b .

[0062] The results are as follows Figure 6 Table 2 shows that high concentrations of chlorine dioxide have a significant impact on the color of corn germ oil. Chlorine dioxide has a noticeable bleaching effect on corn germ oil. Furthermore, in terms of color value, as the concentration of chlorine dioxide increases, the color of corn germ oil decreases. L A significant increase in (brightness) and a (Red and green) and b The decrease in the (yellow-blue) value also indicates that the color of corn germ oil has become brighter. Compared with direct treatment of corn oil with the same concentration of chlorine dioxide, the color change caused by germ treatment is significantly reduced and no unpleasant flavor is produced, indicating that it has little impact on the quality of corn oil.

[0063] Table 2. Effects of different concentrations of chlorine dioxide on the color value of corn germ oil.

[0064] 3. Effect on the antioxidant capacity of corn germ oil: The antioxidant capacity was determined using DPPH. 1 g of corn germ oil was mixed with 5 mL of methanol in a test tube, vortexed for 2 min at room temperature, and allowed to stand for 5 min. Then, it was centrifuged at 6000 r / min for 10 min. After separation, the supernatant was transferred to another test tube and stored in a refrigerator for analysis. 1 mL of the extract was mixed with 1 mL of methanol DPPH (0.8 mmol / L), shaken, and reacted in the dark at room temperature for 30 min. The absorbance was measured at 517 nm using a spectrophotometer. The results are expressed as the percentage of free radicals scavenged by the extract.

[0065] Antioxidant capacity was determined using ABTS. An ABTS solution (25 mL, 7 mmol / L) was mixed with an equal volume of potassium persulfate solution (2.45 mmol / L) and incubated overnight at room temperature. The mixture was then combined with 9 times its volume of methanol to prepare an ABTS radical working solution. 100 μL of the extract and 100 μL of the ABTS radical working solution were mixed thoroughly and reacted for 6 min. The absorbance was measured at 734 nm using a spectrophotometer. Results are expressed as the percentage of free radicals scavenged by the extract.

[0066] The results, shown in Table 3, indicate that chlorine dioxide has a biphasic effect on the antioxidant capacity of corn germ oil. Except for carotenoids, the three antioxidant capacity indicators and total phenol content all increased first and then decreased with increasing chlorine dioxide concentration. In the 1000 mg / L treatment group, only the ABTS antioxidant activity was significantly lower than that in the control group; the other indicators showed no significant differences. However, at 2000 mg / L, chlorine dioxide treatment increased the antioxidant capacity of corn oil against DPPH, ABTS, and FRAP by 58.96%, 23.10%, and 48.39%, respectively. Meanwhile, the carotenoid and total phenol content did not change significantly.

[0067] Table 3. Effects of different concentrations of chlorine dioxide on the antioxidant capacity of corn germ oil.

[0068] 4. Effect on fatty acid content of corn germ oil: The method for determining fatty acid content refers to GB 5009.168-2016 Determination of fatty acids in food.

[0069] The results, as shown in Table 4, indicate that the fatty acid composition of corn oil was dominated by linoleic acid (59.08%), followed by oleic acid (26.50%), palmitic acid (11.21%), and stearic acid (1.67%), with small amounts of linolenic acid and arachidic acid. Compared with the untreated sample, chlorine dioxide significantly altered the fatty acid composition. Except for stearic acid, the concentrations of all fatty acids in the blank group were higher than those in the treated group. The 1000 mg / L treated group retained 81.81% of the fatty acids, higher than other treatment groups.

[0070] Table 4. Effects of different concentrations of chlorine dioxide on the fatty acid content of corn germ oil.

[0071] 5. Effect on the phytosterol content of corn germ oil: The method for determining the phytosterol content refers to GB / T25223-2024 Determination of sterol composition and total sterol content in animal and vegetable oils.

[0072] The results, as shown in Table 5, indicate that the main phytosterols in corn germ oil include campesterol, stigmasterol, and β-sitosterol. However, chlorine dioxide treatment destroys phytosterols and reduces their content; the 1000 mg / L treatment group retained only 90.86%, 89.15%, and 92.95% of the original campesterol, stigmasterol, and β-sitosterol levels, respectively.

[0073] Table 5. Effects of different concentrations of chlorine dioxide on the phytosterol content of corn germ oil.

[0074] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method of reducing zearalenone in corn germ, characterized by, include: Corn germ was soaked in a chlorine dioxide aqueous solution; the concentration of the chlorine dioxide aqueous solution was 1000~2000 mg / L, and the solid-liquid ratio of the corn germ to the chlorine dioxide aqueous solution was 1:10~1:20 g / mL.

2. The method of claim 1, wherein, The concentration of the chlorine dioxide aqueous solution is 1000~1500 mg / L.

3. The method according to claim 1 or 2, characterized in that, The solid-liquid ratio of the corn germ to the chlorine dioxide aqueous solution is 1:10~15 g / mL.

4. The method according to any one of claims 1 to 3, characterized in that, The pH value of the soaking is 1 to 3.

5. The method of claim 4, wherein, The pH value of the soaking is 1~2.

6. The method according to any one of claims 1-5, characterized in that, The soaking temperature is 4~60℃, and the soaking time is 0.5~2 h.

7. The method of claim 6, wherein, The soaking temperature is 20~40℃, and the soaking time is 1~1.5 h.

8. The method according to any one of claims 1-7, characterized in that, The soaking was carried out under sealed conditions.

9. The method according to any one of claims 1-8, characterized in that, The soaking process also includes washing and drying steps.

10. The application of the method for reducing zearalenone in corn germ according to any one of claims 1-9 in the preparation of corn oil.

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