A method of degrading mycotoxins in wheat bran or wholemeal flour

Abstract

The present application relates to a kind of methods for degrading mycotoxin in wheat bran or wholemeal, belong to the field of wheat bran processing.The method includes the following steps: the wheat bran is treated by low-frequency electromagnetic wave at 170-230 DEG C, and low mycotoxin wheat bran is obtained;Or the wheat bran is treated by low-frequency electromagnetic wave at 170-230 DEG C, and low mycotoxin wheat bran is obtained, the low mycotoxin wheat bran is crushed, and is added to the wheat flour, and low mycotoxin wholemeal is obtained.The present application is treated by low-frequency electromagnetic wave at 170-230 DEG C to the wheat bran, when low-frequency electromagnetic wave carries energy and acts on the wheat bran, polar molecules rub and collide to generate heat, finally the temperature of the wheat bran is increased, and high temperature can cause the degradation of mycotoxin, and low mycotoxin wheat bran is obtained.The method is simple in operation, high in processing efficiency, green and energy-saving, more practical, and can improve the safety quality of wheat bran.

Description

TECHNICAL FIELD

[0001] The application relates to a method for degrading mycotoxins in wheat bran or whole wheat flour, and belongs to the field of wheat bran processing. BACKGROUND

[0002] Wheat bran is a by-product in the process of processing flour from wheat, and accounts for about 22-25% of wheat kernels. The wheat bran is rich in vitamin B, dietary fiber, vitamin E and trace elements necessary for the human body, and has extremely high nutritional value.

[0003] Wheat and other grains and products are prone to produce secondary metabolites of fungi under certain temperature and humidity conditions. For example, Fusarium graminearum can produce deoxynivalenol (DON, commonly known as vomitoxin). The vomitoxin has extensive reproductive toxicity, cytotoxicity, immunotoxicity and neurotoxicity, and seriously threatens human and animal health. Fusarium generally grows from the surface of grain kernels to the inside, and the toxin content of the grain cortex is more accumulated than that of the kernel inside. A large number of studies have found that the content of DON in wheat bran obtained after grinding is high, resulting in a decrease in the safety quality of the wheat bran and whole wheat flour processed therefrom.

[0004] Generally, the degradation of DON in wheat bran mainly includes physical methods (physical sorting, heat treatment, irradiation treatment, etc.), chemical methods (ozone fumigation, alkali treatment, etc.), and biological methods (microbial adsorption, transformation, etc.). However, physical sorting can only achieve the redistribution of vomitoxin, and cannot completely degrade it; traditional heat treatment requires a high temperature, has low heat efficiency, and has a long processing time, which causes damage to the quality of the wheat bran; irradiation technology is expensive and requires strict operation techniques, and can easily cause loss of nutrients in the processed sample. The chemical method has a complex reaction, and the use amount and residual amount of the chemical agent are large, which can damage the nutritional value of the grain and cause secondary pollution; the biological method has strict requirements for reaction conditions, and has high cost, which has certain limitations in actual application. SUMMARY

[0005] The application aims to provide a method for degrading mycotoxins in wheat bran or whole wheat flour, so as to solve the problems of complex processing method for degrading mycotoxins in wheat bran in the prior art, limitations, and damaged quality of the obtained wheat bran.

[0006] In order to achieve the above purpose, the technical scheme of the application is as follows:

[0007] The application discloses a method for degrading mycotoxin in wheat bran or whole wheat flour, and comprises the following steps: subjecting the wheat bran to medium-low frequency electromagnetic wave treatment at 170-230 DEG C to obtain low mycotoxin wheat bran; or subjecting the wheat bran to medium-low frequency electromagnetic wave treatment at 170-230 DEG C to obtain low mycotoxin wheat bran, crushing the low mycotoxin wheat bran, and adding the low mycotoxin wheat bran into the wheat flour to obtain low mycotoxin whole wheat flour.

[0008] The application subjects the wheat bran to medium-low frequency electromagnetic wave treatment at 170-230 DEG C, when the medium-low frequency electromagnetic wave carries energy and acts on the wheat bran, the polar molecules rub and collide to generate heat, and finally the temperature of the wheat bran is increased, and the high temperature can cause degradation of the mycotoxin, and the low mycotoxin wheat bran is obtained. The method is simple in operation, high in processing efficiency, green in energy saving, and stronger in practicability, and can improve the safety quality of the wheat bran. The degradation rate of the mycotoxin of the wheat bran subjected to the medium-low frequency electromagnetic wave treatment at 170-230 DEG C is higher.

[0009] The application mixes the treated wheat bran with wheat bran, so that the mycotoxin in the whole wheat flour is reduced, and the safety quality of the whole wheat flour is improved. Moreover, the treatment is higher in efficiency, better in treatment effect and lower in cost than the treatment of the whole wheat flour by the medium-low frequency electromagnetic wave.

[0010] In order to improve the degradation efficiency and effect of the mycotoxin, preferably, the frequency of the medium-low frequency electromagnetic wave treatment is 11 KHz-28 KHz. In order to degrade the mycotoxin in the wheat bran more thoroughly, preferably, the time of the medium-low frequency electromagnetic wave treatment is 5-30 min.

[0011] Preferably, the medium-low frequency electromagnetic wave treatment temperature is 190-230 DEG C, and the time is 20-30 min. Under the medium-low frequency electromagnetic wave treatment at the temperature and the time, the degradation rate of the mycotoxin in the wheat bran is higher. Preferably, the mycotoxin is a secondary metabolite of fusarium graminearum, and the degradation effect of the secondary metabolite of fusarium graminearum is better by the medium-low frequency electromagnetic wave treatment. Further preferably, the secondary metabolite is deoxynivalenol. The method of the application is best in the degradation effect of deoxynivalenol in the wheat bran.

[0012] Preferably, the content of the deoxynivalenol in the wheat bran is not less than 8 mg / kg before the medium-low frequency electromagnetic wave treatment. When the content of the deoxynivalenol in the wheat bran is more than 8 mg / kg, the degradation rate of the DON reaches more than 25% by the medium-low frequency electromagnetic wave treatment of the application. BRIEF DESCRIPTION OF DRAWINGS

[0013] Figure 1 A flow chart for degrading mycotoxin in wheat bran or whole wheat flour of the application. DETAILED DESCRIPTION

[0014] The present application obtains low-fungus-toxin bran by treating the bran obtained after grinding wheat with medium-low frequency electromagnetic wave. When the medium-low frequency electromagnetic wave carries energy to act on the bran, the polar molecules rub and collide to generate heat, and finally the temperature of the bran is increased. High temperature can cause degradation of mycotoxins, and low-fungus-toxin bran is obtained. The bran with a water content of 10-21%, preferably 12-16%, is generally selected for medium-low frequency electromagnetic wave treatment.

[0015] The medium-low frequency electromagnetic wave is an electromagnetic field in which the electric field and the magnetic field oscillate in phase and are perpendicular to each other, and can effectively transfer energy and momentum. The heating mode is from inside to outside, and the heating efficiency is higher than that of traditional heating methods.

[0016] The present application performs hair and chaff cleaning, wheat moistening, and light wheat cleaning to obtain bran and flour (i.e., wheat flour) by milling. The bran is transported by a conveyor belt through a medium-low frequency electromagnetic wave treatment area for medium-low frequency electromagnetic wave treatment and crushing, and then the crushed bran is mixed with the flour to obtain whole wheat flour. The specific flow chart is shown in Figure 1 .

[0017] The wheat of Examples 1-6 and Comparative Example 1 is the same batch of wheat, and the content of DON in the untreated bran is about 8.31 mg / kg.

[0018] The technical solutions of the present application are further described in combination with the specific embodiments.

[0019] I. The specific implementation of the method for degrading mycotoxins in bran or whole wheat flour of the present application is as follows:

[0020] Example 1

[0021] The method for degrading mycotoxins in whole wheat flour of this embodiment adopts the following steps:

[0022] (1) The wheat with excessive mycotoxins is treated, and the bran with a water content of 12% obtained by the wheat milling process is transported by a conveyor belt through a medium-low frequency electromagnetic wave treatment area;

[0023] (2) The temperature of the medium-low frequency electromagnetic wave generator is set to 170°C, and the conveyor belt speed is controlled so that the bran passes through the medium-low frequency electromagnetic wave treatment area for 20 minutes. The medium-low frequency electromagnetic wave generator automatically adjusts the working frequency through the set temperature, and the working frequency range is 11 KHz-28 KHz. The bran is treated, the polar molecules rub and collide to generate heat, the bran is heated to 170°C, and when the temperature reaches 170°C, the medium-low frequency electromagnetic wave generator keeps the temperature constant through frequency conversion;

[0024] (3) The bran treated by the medium-low frequency electromagnetic wave is crushed and uniformly mixed with the wheat flour to obtain whole wheat flour.

[0025] Example 2

[0026] The method for degrading the mycotoxin in the whole wheat flour in this example adopts the following steps:

[0027] (1) The wheat with excessive mycotoxin is treated, and the bran with a moisture content of 14.5% obtained in the wheat flour processing is transported by a conveying belt through a low-frequency electromagnetic wave treatment area;

[0028] (2) The temperature of the low-frequency electromagnetic wave generator is set to 190°C, the conveying belt speed is controlled, and the bran is allowed to pass through the low-frequency electromagnetic wave treatment area for 20 min; the low-frequency electromagnetic wave generator automatically adjusts the working frequency through the set temperature, and the working frequency range is 11 KHz-28 KHz, so as to treat the bran, generate heat through the friction and collision of polar molecules, and heat the bran to 190°C; when the temperature reaches 190°C, the low-frequency electromagnetic wave generator keeps the temperature constant through frequency conversion;

[0029] (3) The bran treated by the low-frequency electromagnetic wave is crushed and uniformly mixed with the wheat flour to obtain the whole wheat flour.

[0030] Example 3

[0031] The method for degrading the mycotoxin in the whole wheat flour in this example adopts the following steps:

[0032] (1) The wheat with excessive mycotoxin is treated, and the bran with a moisture content of 14% obtained in the wheat flour processing is transported by a conveying belt through a low-frequency electromagnetic wave treatment area;

[0033] (2) The temperature of the low-frequency electromagnetic wave generator is set to 210°C, the conveying belt speed is controlled, and the bran is allowed to pass through the low-frequency electromagnetic wave treatment area for 20 min; the low-frequency electromagnetic wave generator automatically adjusts the working frequency through the set temperature, and the working frequency range is 11 KHz-28 KHz, so as to treat the bran, generate heat through the friction and collision of polar molecules, and heat the bran to 210°C; when the temperature reaches 190°C, the low-frequency electromagnetic wave generator keeps the temperature constant through frequency conversion;

[0034] (3) The bran treated by the low-frequency electromagnetic wave is crushed and uniformly mixed with the wheat flour to obtain the whole wheat flour.

[0035] Example 4

[0036] The method for degrading the mycotoxin in the whole wheat flour in this example adopts the following steps:

[0037] (1) The wheat with excessive mycotoxins is treated, and the bran with a water content of 15.5% obtained by a wheat milling process is transported by a conveyor through a low-frequency electromagnetic wave treatment area;

[0038] (2) The temperature of the low-frequency electromagnetic wave generator is set to 230°C, the conveyor speed is controlled, and the bran passes through the low-frequency electromagnetic wave treatment area for 20 min; the low-frequency electromagnetic wave generator automatically adjusts the working frequency through the set temperature, and the working frequency range is 11 KHz-28 KHz, the bran is treated, the polar molecules rub and collide to generate heat, the bran is heated to 230°C, and when the temperature reaches 230°C, the low-frequency electromagnetic wave generator keeps the temperature constant through frequency conversion;

[0039] (3) The low-frequency electromagnetic wave treated bran is crushed and uniformly mixed with wheat flour to obtain whole wheat flour.

[0040] Example 5

[0041] The method for degrading mycotoxins in whole wheat flour in this embodiment adopts the following steps:

[0042] (1) The wheat with excessive mycotoxins is treated, and the bran with a water content of 13% obtained by a wheat milling process is transported by a conveyor through a low-frequency electromagnetic wave treatment area;

[0043] (2) The temperature of the low-frequency electromagnetic wave generator is set to 190°C, the conveyor speed is controlled, and the bran passes through the low-frequency electromagnetic wave treatment area for 5 min; the low-frequency electromagnetic wave generator automatically adjusts the working frequency through the set temperature, and the working frequency range is 11 KHz-28 KHz, the bran is treated, the polar molecules rub and collide to generate heat, the bran is heated to 190°C, and when the temperature reaches 190°C, the low-frequency electromagnetic wave generator keeps the temperature constant through frequency conversion;

[0044] (3) The low-frequency electromagnetic wave treated bran is crushed and uniformly mixed with wheat flour to obtain whole wheat flour.

[0045] Example 6

[0046] The method for degrading mycotoxins in whole wheat flour in this embodiment adopts the following steps:

[0047] (1) The wheat with excessive mycotoxins is treated, and the bran with a water content of 13.5% obtained by a wheat milling process is transported by a conveyor through a low-frequency electromagnetic wave treatment area;

[0048] (2) Set the temperature of the medium-low frequency electromagnetic wave generator to 190℃, control the speed of the conveying belt, and make the bran pass through the medium-low frequency electromagnetic wave treatment area for 30 min; the medium-low frequency electromagnetic wave generator automatically adjusts the working frequency through the set temperature, and the working frequency range is 11 KHz-28 KHz, to treat the bran. The polar molecules rub and collide to generate heat, so that the bran is heated to 190℃. When it reaches 190℃, the medium-low frequency electromagnetic wave generator will keep the temperature constant through frequency conversion;

[0049] (3) Crush the bran treated by the medium-low frequency electromagnetic wave, mix it evenly with the wheat flour, and obtain whole wheat flour.

[0050] II. Comparative Example

[0051] Comparative Example 1

[0052] The method for degrading mycotoxins in whole wheat flour in this comparative example adopts the following steps:

[0053] (1) Treat the wheat with excessive mycotoxins, and transport the bran with a water content of 12% obtained by wheat flour processing through the medium-low frequency electromagnetic wave treatment area by the conveying belt;

[0054] (2) Set the temperature of the medium-low frequency electromagnetic wave generator to 150℃, control the speed of the conveying belt, and make the bran pass through the medium-low frequency electromagnetic wave treatment area for 20 min; the medium-low frequency electromagnetic wave generator automatically adjusts the working frequency through the set temperature, and the working frequency range is 11 KHz-28 KHz, to treat the bran. The polar molecules rub and collide to generate heat, so that the bran is heated to 150℃. When it reaches 150℃, the medium-low frequency electromagnetic wave generator will keep the temperature constant through frequency conversion;

[0055] (3) Crush the bran treated by the medium-low frequency electromagnetic wave, mix it evenly with the wheat flour, and obtain whole wheat flour.

[0056] III. Experimental Example

[0057] This experimental example determines the content of deoxynivalenol in the bran treated by the medium-low frequency electromagnetic wave in Examples 1-6 and Comparative Example 1, and the untreated bran is used as a control group, wherein the bran is scab bran. The results are shown in Table 1.

[0058] The test method is:

[0059] DON extraction: refer to the first method in GB 5009.111-2016 "Determination of Deoxynivalenol and Its Acetylated Derivatives in Food" with slight optimization. Weigh 10 g (accurate to 0.1 g) of bran sample crushed and passed through a 40 mesh sieve into a 300 mL glass beaker, add 100 mL extraction solution (V 乙腈 : V水 = 84:16), placed on a magnetic stirrer for stirring for 20 min, and after the stirring was completed, standing for 5 min. The supernatant after standing was taken and placed in a high-speed centrifuge, centrifuged at 4000 r / min for 5 min, and the supernatant after centrifugation was collected and reserved.

[0060] Purification: 5 ml of the supernatant after centrifugation was taken and passed through a mycotoxin multifunctional purification column, 4 ml of filtrate was accurately taken in a test tube, and nitrogen was blown under a water bath at 50 ℃. 1 ml of mobile phase (V 甲醇 :V 水 = 10:90) was used for redissolution, and after mixing, the mixture was placed in a high-speed centrifuge and centrifuged at 12000 r / min for 5 min. The supernatant was filtered through a 0.22 μm organic filter membrane, and the filtrate was reserved for use at 4 ℃ in the dark.

[0061] Preparation of a DON standard solution: 1 mg of a DON standard was dissolved in 10 mL of an acetonitrile solution to prepare a DON standard stock solution with a mass concentration of 100 μg / mL, which was stored at 4 ℃ for use. Before use, the standard stock solution was first restored to room temperature, and then 0.5 mL of the standard stock solution was blown dry with nitrogen, and the DON standard working solution was diluted to 0.1, 0.2, 0.5, 1, 2, 5, and 10 μg / mL with a mobile phase, which was stored at 4 ℃ in the dark.

[0062] DON detection: an ultra-high performance liquid chromatograph-mass spectrometer was used for quantitative detection of DON. The chromatographic parameters were as follows: a C18 chromatographic column (100 x 2.1 mm, 1.7 μm), a column temperature of 35 ℃, a mobile phase of A (containing 5 mmol / L ammonium acetate and 0.1% formic acid water) and B (methanol), an injection amount of 10 μL, and a flow rate of 0.30 mL / min. The mass spectrometry parameters were as follows: DON was selected in a positive ion mode, and the scanning mode was a first-order full scan (Full Ms).

[0063] As shown in Table 1, after the wheat bran with scab was treated by the method of the present application, the degradation rate of deoxynivalenol in the wheat bran was obviously improved. When the temperature of the medium-low frequency electromagnetic wave was 150 ℃, the degradation rate of DON was only 9.62%, and the degradation effect was almost negligible. Therefore, the treatment of the medium-low frequency electromagnetic wave at the temperature of the present application can significantly degrade deoxynivalenol in the wheat bran. When the treatment temperature is higher than 230 ℃, the quality of the bran will be seriously damaged, and the bran has no application value.

[0064] Table 1: Influence of medium-low frequency electromagnetic wave treatment on the content of deoxynivalenol in wheat bran

[0065] Sample Temperature (°C) Time (min) DON content (mg / kg) DON degradation rate (%) Control -- -- 8.31±0.34 0 Example 1 170 20 5.11±0.05 38.51 Example 5 190 5 6.13±0.07 26.23 Example 2 190 20 3.19±0.09 61.61 Example 6 190 30 2.61±0.08 68.59 Example 5 210 20 2.44±0.06 70.64 Example 4 230 20 0.57±0.04 93.14 Comparative Example 1 150 20 7.51±0.13 9.62

Claims

1. A method for degrading mycotoxins in wheat bran or whole wheat flour, characterized in that, The process includes the following steps: treating wheat bran with low-frequency electromagnetic waves at 170~230 ℃ to obtain wheat bran with low mycotoxin levels; or treating wheat bran with low-frequency electromagnetic waves at 170~230 ℃ to obtain wheat bran with low mycotoxin levels, pulverizing the wheat bran with low mycotoxin levels, and adding it back to wheat flour to obtain whole wheat flour with low mycotoxin levels; the frequency of the low-frequency electromagnetic wave treatment is 11 kHz ~ 28 kHz; the mycotoxin is deoxynivalenol; and the treatment time is 5~30 min.

2. The method for degrading mycotoxins in wheat bran or whole wheat flour according to claim 1, characterized in that, The medium- and low-frequency electromagnetic wave processing temperature is 190-230 ℃, and the time is 20-30 min.

3. The method for degrading mycotoxins in wheat bran or whole wheat flour according to claim 1 or 2, characterized in that, The moisture content of the wheat bran is 10-21%.

4. The method for degrading mycotoxins in wheat bran or whole wheat flour according to claim 3, characterized in that, The moisture content of the wheat bran is 12-16%.

5. The method for degrading mycotoxins in wheat bran or whole wheat flour according to claim 1 or 2, characterized in that, Before treatment with low- and medium-frequency electromagnetic waves, the content of deoxynivalenol in the wheat bran is not less than 8 mg / kg.

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