A method for removing aflatoxin from vegetable oil

Abstract

The present invention provides a method for removing aflatoxin from vegetable oil, the method comprising using a pulsed strong light with a minimum wavelength between 280nm and 320nm at a speed of ≥11J / cm 2 The invention also relates to a step of irradiating aflatoxin-containing vegetable oil with a radiation dose of 100 nm. The invention also relates to a vegetable oil free of aflatoxin obtained by the method of the invention, and the use of a pulsed strong light with a minimum wavelength between 280 nm and 320 nm in removing aflatoxin from vegetable oil. The method of the invention can reduce the aflatoxin content in vegetable oil by more than 90% without affecting the quality of the oil.

Description

Technical Field

[0001] The invention belongs to the technical field of edible oil processing, and particularly relates to a method for removing aflatoxin from vegetable oil. Background Art

[0002] Aflatoxin is a highly toxic compound, often produced by Aspergillus flavus and several other molds such as Aspergillus parasiticus in moldy grains, such as rice, beans, peanuts, etc. It is the strongest carcinogen so far. At least 2% of agricultural products in the world are scrapped every year due to aflatoxin contamination. Currently, about 100 countries have set strict limits on the content of aflatoxin in food. Aflatoxin contamination is relatively serious in some oil crops in my country, especially in peanuts and corn, resulting in frequent excess of aflatoxin content in vegetable oils. This has also caused a higher incidence of cancer in some areas. Therefore, taking effective measures to reduce the content of aflatoxin in vegetable oils has high social and economic value.

[0003] For the removal of aflatoxins from vegetable oils, the adsorption method is currently widely used. Adsorbents such as activated carbon, activated clay, and diatomaceous earth are added to vegetable oils to decolorize the crude oil while adsorbing some aflatoxins. This method is low-cost, but excessive addition of adsorbents will affect the flavor of the oil. In addition, other removal methods, such as chemical oxidation and microbial degradation, all have the defects of high cost and damage to oil quality to varying degrees. Summary of the invention

[0004] In view of the shortcomings of the above-mentioned technologies, the present invention proposes a method for removing aflatoxin from vegetable oil. The method of the present invention can achieve rapid and effective removal of aflatoxin from vegetable oil while keeping the oil quality substantially unaffected.

[0005] Specifically, the present invention provides a method for removing aflatoxin from vegetable oil, the method comprising using a pulsed intense light with a minimum wavelength between 280nm and 320nm at a power of ≥11J / cm 2 Steps for irradiating vegetable oil containing aflatoxin with an irradiation dose of

[0006] In one or more embodiments, the irradiation time is from 6 seconds to 30 seconds, preferably from 6 seconds to 20 seconds.

[0007] In one or more embodiments, the vegetable oil is exposed to 30-60 pulses of intense pulsed light.

[0008] In one or more embodiments, the irradiation dose is 11 J / cm 2 -40J / cm 2 .

[0009] In one or more embodiments, the pulse width of the intense pulse light is between 340 μs and 380 μs, and / or the pulse frequency of the intense pulse light is 2-5 pulses / second.

[0010] In one or more embodiments, the thickness of the vegetable oil on one side in the direction irradiated with the intense pulse light is 0.5 cm to 1 cm.

[0011] In one or more embodiments, the vegetable oil is selected from the group consisting of rice oil, sunflower oil, rapeseed oil, palm oil, palm kernel oil, peanut oil, rapeseed oil, soybean oil, cottonseed oil, safflower seed oil, perilla seed oil, tea seed oil, olive oil, cocoa bean oil, Chinese tallow seed oil, almond oil, apricot kernel oil, tung seed oil, rubber seed oil, corn oil, wheat germ oil, sesame seed oil, castor seed oil, evening primrose seed oil, hazelnut oil, pumpkin seed oil, walnut oil, grape seed oil, borage seed oil, sea buckthorn seed oil, tomato seed oil, macadamia nut oil, coconut oil, cocoa butter and algae oil; preferably peanut oil and / or corn oil.

[0012] In one or more embodiments, a cutoff optical glass with a transmission limit wavelength between 280nm-320nm is arranged between the pulsed strong light source and the vegetable oil, so that the vegetable oil is irradiated by the pulsed strong light with a minimum wavelength between 280nm-320nm.

[0013] In one or more embodiments, the distance between the light source and the vegetable oil is selected according to the transmittance of the cut-off optical glass, the pulse width and the pulse frequency of the pulsed strong light, so that the vegetable oil receives 11 J / cm within 6 seconds to 30 seconds. 2 -40J / cm 2 of radiation dose.

[0014] The present invention also provides aflatoxin-free vegetable oil prepared by the method described in any embodiment of the present invention; preferably, the vegetable oil is corn oil and / or peanut oil.

[0015] The present invention also provides the use of strong pulse light with a minimum wavelength between 280nm and 320nm in removing aflatoxin from vegetable oil.

[0016] In one or more embodiments, in the use, the irradiation time of the pulsed intense light is 6 seconds to 30 seconds, preferably 6 seconds to 20 seconds.

[0017] In one or more embodiments, in the use, the number of pulses of intense pulsed light received by the vegetable oil is 30-60.

[0018] In one or more embodiments, the irradiation dose of the pulsed intense light is 11 J / cm 2 -40J / cm2 .

[0019] In one or more embodiments, in the use, the pulse width of the pulsed intense light is between 340 μs and 380 μs, and / or the pulse frequency of the pulsed intense light is 2-5 pulses / second.

[0020] In one or more embodiments, in the use, the single-side thickness of the vegetable oil in the direction irradiated with the pulsed intense light is 0.5 cm to 1 cm.

[0021] In one or more embodiments, in the use, the vegetable oil is selected from: rice oil, sunflower oil, rapeseed oil, palm oil, palm kernel oil, peanut oil, rapeseed oil, soybean oil, cottonseed oil, safflower seed oil, perilla seed oil, tea seed oil, olive oil, cocoa bean oil, Chinese tallow seed oil, almond oil, apricot kernel oil, tung seed oil, rubber seed oil, corn oil, wheat germ oil, sesame seed oil, castor seed oil, evening primrose seed oil, hazelnut oil, pumpkin seed oil, walnut oil, grape seed oil, borage seed oil, sea buckthorn seed oil, tomato seed oil, macadamia oil, coconut oil, cocoa butter and algae oil; preferably peanut oil and / or corn oil.

[0022] In one or more embodiments, in the use, a cutoff optical glass with a transmission limit wavelength between 280nm-320nm is arranged between the pulsed strong light source and the vegetable oil, so that the vegetable oil is irradiated by the pulsed strong light with a minimum wavelength between 280nm-320nm.

[0023] In one or more embodiments, in the use, the distance between the light source and the vegetable oil is selected according to the transmittance of the cut-off optical glass, the pulse width and the pulse frequency of the pulsed strong light, so that the vegetable oil receives 11J / cm within 6 seconds to 30 seconds. 2 -40J / cm 2 of radiation dose. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 is the spectral transmission curve, where λ is the wavelength, tj is the transmission limit wavelength, T is the transmittance, T M is the maximum transmittance, T M / 2 is 50% of the maximum transmittance. DETAILED DESCRIPTION

[0025] In order to enable those skilled in the art to understand the characteristics and effects of the present invention, the following is a general description and definition of the terms and expressions mentioned in the specification and claims. Unless otherwise specified, all technical and scientific terms used in the text are the common meanings understood by those skilled in the art for the present invention. In the event of a conflict, the definition in this specification shall prevail.

[0026] The theories or mechanisms described and disclosed herein, whether correct or incorrect, should not limit the scope of the present invention in any way, that is, the present invention can be implemented without being limited by any specific theory or mechanism.

[0027] Herein, “comprising,” “including,” “containing,” “having” and similar terms encompass the meanings of “consisting essentially of” and “consisting of,” for example, when this document discloses “A comprises B and C,” “A consists of B and C” should be deemed to have been disclosed herein.

[0028] In this article, all features such as values, quantities, contents and concentrations defined in the form of numerical ranges or percentage ranges are only for brevity and convenience. Accordingly, the description of numerical ranges or percentage ranges should be considered to have included and specifically disclosed all possible secondary ranges and individual values ​​within the range (including integers and fractions).

[0029] Herein, when describing embodiments or examples, it should be understood that they are not used to limit the present invention to these embodiments or examples. On the contrary, all substitutes, improvements and equivalents of the methods and materials described in the present invention can be included in the scope limited by the claims.

[0030] In this document, in order to make the description concise, not all possible combinations of various technical features in various embodiments or examples are described. Therefore, as long as there is no contradiction in the combination of these technical features, the various technical features in various embodiments or examples can be combined arbitrarily, and all possible combinations should be considered to be within the scope of this specification.

[0031] Herein, transmittance (T) refers to the ratio of the transmitted light flux to the incident light flux at a certain wavelength.

[0032] In this paper, the transmission limit wavelength (λ tj ) refers to the spectral transmission curve (such as Figure 1 The wavelength at which the transmittance is 50% of the maximum transmittance.

[0033] The present invention found that the use of pulsed intense light with a minimum wavelength between 280nm and 320nm at ≥11J / cm 2Irradiating vegetable oil containing aflatoxin with an irradiation dose of can quickly and effectively reduce the aflatoxin content of the vegetable oil (the aflatoxin removal rate can reach more than 90%), while keeping the oil quality (including acid value, peroxide value and flavor) basically unaffected, thereby completing the present invention.

[0034] Therefore, the present invention provides the use of pulsed strong light with a minimum wavelength between 280nm and 320nm in removing aflatoxins from vegetable oil.

[0035] The present invention also provides a method for removing aflatoxin from vegetable oil, the method comprising using a pulsed strong light with a minimum wavelength between 280nm and 320nm at a power of ≥11J / cm 2 Steps for irradiating vegetable oil containing aflatoxin with an irradiation dose of

[0036] Vegetable oils suitable for the present invention include, but are not limited to, rice oil, sunflower seed oil, rapeseed oil, palm oil, palm kernel oil, peanut oil, rapeseed oil, soybean oil, cottonseed oil, safflower seed oil, perilla seed oil, tea seed oil, olive oil, cocoa bean oil, Chinese tallow seed oil, almond oil, apricot kernel oil, tung oil, rubber seed oil, corn oil, wheat germ oil, sesame seed oil, castor seed oil, evening primrose seed oil, hazelnut oil, pumpkin seed oil, walnut oil, grape seed oil, borage seed oil, sea buckthorn seed oil, tomato seed oil, macadamia nut oil, coconut oil, cocoa butter and algae oil. Preferred vegetable oils are those susceptible to aflatoxin contamination, including but not limited to peanut oil and corn oil.

[0037] In the present invention, pulsed intense light is a broad spectrum light in the form of pulses that release high energy in a very short time. The duration of a single pulse of pulsed intense light (i.e., pulse width) is usually tens to hundreds of microseconds, and the intensity of a single pulse can reach hundreds of joules. The minimum wavelength of the pulsed intense light can reach 90nm, and the maximum wavelength can reach 1200nm. The present invention utilizes pulsed intense light with a minimum wavelength between 280nm and 320nm to remove aflatoxin.

[0038] In the present invention, the irradiation time is usually within 6-30 seconds. Too long irradiation time will seriously affect the quality of vegetable oil. It should be understood that if the irradiation dose is low, the irradiation time can be appropriately extended, and if the irradiation dose is high, the irradiation time can be appropriately shortened. In a preferred embodiment, the irradiation time is 6-20 seconds. In some embodiments, the irradiation time is 6-15 seconds.

[0039] In the present invention, a certain attenuation will occur when the pulsed strong light penetrates the vegetable oil layer. If the thickness of the oil layer is too large, the vegetable oil farther from the light source in the direction of the pulsed strong light irradiation will not receive enough irradiation energy. The unilateral thickness of the vegetable oil in the direction of the pulsed strong light irradiation is 0.5cm-1cm. The unilateral thickness described herein refers to the thickness of the vegetable oil when the pulsed strong light is irradiated from one side. When the pulsed strong light is irradiated from two opposite sides at the same time, the thickness of the vegetable oil can reach 1.0-2.0cm.

[0040] In some embodiments, a section of the vegetable oil delivery pipeline is set as a transparent annular pipeline, the pipeline material is a cut-off optical glass with a transmission limit wavelength between 280nm-320nm, the diameter of the channel through which the vegetable oil flows is 0.5cm-1cm, and a pulsed strong light irradiation device is arranged around this pipeline to complete the irradiation during the vegetable oil delivery process. It should be understood that if a pulsed strong light irradiation device is arranged around the pipeline, the diameter of the passage through which the vegetable oil flows can be 1.0-2.0cm. In other embodiments, a section of the vegetable oil delivery pipeline is set as a transparent square pipeline, the pipeline material is a cut-off optical glass with a transmission limit wavelength between 280nm-320nm, and the pipeline can pass vegetable oil with a thickness of 0.5cm-1cm, and a pulsed strong light irradiation device is arranged in the thickness direction of this pipeline. When the pulsed strong light is irradiated from both sides opposite to each other at the same time, the thickness of the vegetable oil can reach 1.0-2.0cm. In the present invention, the strong pulse light with a minimum wavelength between 280nm and 320nm can be obtained by filtering the strong pulse light using a cut-off optical glass with a transmission limit wavelength between 280nm and 320nm. The transmittance of the cut-off optical glass suitable for the present invention is preferably ≥85%. The cut-off optical glass with a transmission limit wavelength between 280nm and 320nm is commercially available, for example, the ZJB cut-off filter of Nantong Yinxing Optical Co., Ltd. has a transmission limit wavelength between 280nm and 320nm and a transmittance of ≥85%. The maximum wavelength of the strong pulse light suitable for the present invention is preferably between 1000nm and 1200nm, for example, 1100nm±50nm. A known pulsed strong light source can be made to pass through a cutoff optical glass with a transmission limit wavelength between 280nm and 320nm to obtain a pulsed strong light with a minimum wavelength between 280nm and 320nm. For example, using the SteriPule-XL 3000 pulsed strong light sterilization system of Xenon Corporation of the United States, a pulsed strong light with a minimum wavelength of 100±10nm and a maximum wavelength of 1100±100nm can be obtained, and the pulsed strong light can be made to pass through a cutoff optical glass with a transmission limit wavelength between 280nm and 320nm.

[0041] In the present invention, the number of pulses of the pulsed intense light received by the vegetable oil is preferably 30-60. The distance between the light source of the pulsed intense light and the surface of the vegetable oil is preferably ≤10 cm, for example 3-10 cm. Controlling the number of pulses of the pulsed intense light and the distance between the light source and the surface of the vegetable oil within the aforementioned range is beneficial for effectively removing aflatoxin from the vegetable oil while maintaining the quality of the vegetable oil.

[0042] In the present invention, the maximum wavelength of the pulsed strong light received by the vegetable oil can be between 1000nm-1200nm, for example, 1100±50nm. The pulse width of the pulsed strong light received by the vegetable oil can be between 340μs-380μs, for example, 360±10μs. The pulse frequency of the pulsed strong light received by the vegetable oil can be 2-5 pulses / s, for example, 3 pulses / s, 4 pulses / s. The intensity of the pulsed strong light received by the vegetable oil can be 380-550J / pulse, for example, 420-515J / pulse. The irradiation dose received by the vegetable oil can be 11-40J / cm 2 .

[0043] In some embodiments, the pulsed intense light received by the vegetable oil is a pulsed intense light that is filtered using a cutoff optical glass with a transmission limit wavelength between 280nm and 320nm to filter the pulsed intense light emitted by the pulsed intense light source, whose minimum wavelength is less than 280nm. The minimum wavelength of the pulsed intense light emitted by the pulsed intense light source may be between 90nm and 110nm, for example, 100±5nm. The maximum wavelength of the pulsed intense light emitted by the pulsed intense light source may be between 1000nm and 1200nm, for example, 1100±50nm. The pulse width of the pulsed intense light emitted by the pulsed intense light source may be between 340μs and 380μs, for example, 360±10μs. The intensity of the pulsed intense light emitted by the pulsed intense light source may be 450-550J / pulse, for example, 505±10J / pulse. The pulsed intense light source may emit 2-5, for example, 3 or 4 pulses per second.

[0044] The present invention finds that strong pulsed light with a minimum wavelength below 280nm, after being filtered through a cut-off optical glass with a limit wavelength between 280nm and 320nm, can quickly and effectively reduce the aflatoxin content of the vegetable oil, as shown in that the aflatoxin removal rate can reach more than 90% within one minute, while keeping the oil quality (including acid value, peroxide value and flavor) basically unaffected.

[0045] The present invention also provides a method for removing aflatoxin from vegetable oil, which comprises using a cut-off optical glass with a transmission limit wavelength between 280nm and 320nm to filter pulsed strong light with a minimum wavelength below 280nm and then irradiate the vegetable oil containing aflatoxin.

[0046] The present invention finds that when the transmission limit wavelength of the cut-off optical glass is lower than 280nm, it is not conducive to maintaining the quality of the vegetable oil; when the transmission limit wavelength of the cut-off optical glass is higher than 320nm, aflatoxin in the vegetable oil cannot be effectively removed, and the removal rate is difficult to reach more than 90%; when the transmission limit wavelength of the cut-off optical glass is between 280nm-32nm, aflatoxin in the vegetable oil can be effectively removed, and the removal rate can reach more than 90%, while maintaining the quality of the vegetable oil.

[0047] In an embodiment in which a cutoff optical glass with a transmission limit wavelength between 280nm and 320nm is used to filter pulsed intense light with a minimum wavelength below 280nm and then irradiate vegetable oil containing aflatoxin, the cutoff optical glass with a transmission limit wavelength between 280nm and 320nm can be as described in any of the preceding embodiments; the pulsed intense light with a minimum wavelength below 280nm can be as described in any of the preceding embodiments, for example, it can be the pulsed intense light emitted by the pulsed intense light light source described in any of the preceding embodiments; the variety, quality, thickness in the direction of receiving the pulsed intense light irradiation, the received pulsed intense light and irradiation dose of the vegetable oil can be as described in any of the preceding embodiments.

[0048] The present invention achieves the removal of aflatoxin in vegetable oil in a very short time. In the present invention, the vegetable oil may be irradiated with pulsed strong light for 6-30 seconds, such as 10-20 seconds.

[0049] The vegetable oil can be placed in a flat container or a tubular container, and a cut-off optical glass with a transmission limit wavelength between 280nm and 320nm is set between the pulsed strong light source and the flat container or the tubular container containing the vegetable oil, so that the vegetable oil is irradiated with the pulsed strong light with a minimum wavelength between 280nm and 320nm. The material of the container can be glass. A flat container refers to a container whose size in one direction is significantly smaller than that in other directions. The direction with the smaller size is usually called the thickness direction of the container.

[0050] The present invention has the following beneficial effects: the method for removing aflatoxins from vegetable oils of the present invention can reduce the aflatoxins content in vegetable oils by more than 90% in a very short time, while the oil loss is almost zero, and the oil quality (acid value, peroxide value and flavor) is kept basically unaffected. The "basically unaffected" mentioned herein means that the acid value, peroxide value and flavor change within 6% relative to the untreated state. In a preferred embodiment, the acid value changes within 6% relative to the untreated state, the peroxide value changes within 1% relative to the untreated state, and the flavor changes within 5% relative to the untreated state.

[0051] The present invention will be described below in the form of specific examples. It should be understood that these examples are merely illustrative and are not intended to limit the scope of the present invention. The methods, reagents and materials used in the examples are, unless otherwise stated, conventional methods, reagents and materials in the art. The raw materials in the examples can all be purchased through commercial sources.

[0052] In the following examples and comparative examples, the following detection and evaluation methods were used:

[0053] 1. Acid value: refer to the cold solvent indicator titration method (first method) in GB 5009.229-2016.

[0054] 2. Peroxide value: refer to the titration method (first method) in GB 5009.227-2016.

[0055] 3. Aflatoxin B1: refer to the high performance liquid chromatography-post-column derivatization method (method 3) in GB 5009.22-2016.

[0056] 4. The flavor evaluation method is: 12 sensory evaluators are randomly selected to smell and score the flavor preference (0-10 points). The scoring criteria are: very dislike (1 point), very dislike (2 points), dislike (3 points), not very like (4 points), neither dislike nor dislike (5 points), slightly like (6 points), generally like (7 points), like (8 points), very much like (9 points), very much like (10 points). Finally, the average score of the same oil is taken as the final flavor score of the oil.

[0057] In the following examples and comparative examples, the pulsed light sterilization system is SteriPule-XL3000 from Xenon, USA; the parameters of the pulsed light sterilization system are: the system emits 3 pulses with a wavelength of 100-1100nm per second, the pulse width is 360μs, and the output energy is 505J / pulse; the irradiation dose received by the vegetable oil is measured by a laser energy meter (Gentec QE 12LP, Gentec-EO, Canada). The cut-off optical glass is the ZJB cut-off filter from Nantong Yinxing Optical Co., Ltd.

[0058] Example 1

[0059] Aflatoxin B1 is added to the finished peanut oil to obtain peanut oil with an aflatoxin B1 content of 30 ppb. 50 g of the above peanut oil is put into a glass plate with a diameter of 10 cm, and a cut-off optical glass with a diameter of 12 cm and a thickness of 2 mm is covered on the top, with a transmission limit wavelength of 280 nm and a transmittance of 95%. The glass plate containing the peanut oil is placed in a pulsed strong light sterilization system, and the distance from the lamp to the oil surface is kept at 5 cm. Turn on the pulsed strong light, and after irradiating 30 pulses, the peanut oil is taken out to obtain peanut oil 1.

[0060] Example 2

[0061] Aflatoxin B1 is added to the finished peanut oil to obtain peanut oil with an aflatoxin B1 content of 30 ppb. 50 g of the above peanut oil is placed in a glass plate with a diameter of 10 cm, and a cut-off optical glass with a diameter of 12 cm and a thickness of 2 mm is placed on the top, with a transmission limit wavelength of 300 nm and a transmittance of 89.5%. The glass plate containing the peanut oil is placed in a pulsed strong light sterilization system, and the distance from the lamp to the oil surface is kept at 3 cm. Turn on the pulsed strong light, and after irradiating 50 pulses, the peanut oil is taken out to obtain peanut oil 2.

[0062] Example 3

[0063] Peanut kernels contaminated by Aspergillus flavus were taken, and crude oil was squeezed out with a small oil press. After filtering with qualitative filter paper, clear and transparent self-pressed peanut oil was obtained. 50g of the above peanut oil was put into a glass plate with a diameter of 10cm, and a cut-off optical glass with a diameter of 12cm and a thickness of 2mm was covered on the top, with a limit wavelength of 320nm and a transmittance of 85%. The glass plate containing peanut oil was placed in a pulsed strong light sterilization system, and the distance from the lamp to the oil surface was kept at 10cm. The pulsed strong light was turned on, and after 60 pulses were irradiated, the peanut oil was taken out to obtain peanut oil 3.

[0064] Example 4

[0065] Aflatoxin B1 is added to the finished corn oil to obtain corn oil with an aflatoxin B1 content of 30 ppb. 50 g of the corn oil is placed in a glass dish with a diameter of 10 cm, and a cut-off optical glass with a diameter of 12 cm and a thickness of 2 mm is placed on the top, with a transmission limit wavelength of 320 nm and a transmittance of 85%. The glass dish containing corn oil is placed in a pulsed strong light sterilization system, and the distance from the lamp to the oil surface is kept at 8 cm. Turn on the pulsed strong light, and after irradiating 40 pulses, take out the corn oil to obtain corn oil 1.

[0066] Comparative Example 1

[0067] Add aflatoxin B1 to the finished peanut oil to obtain peanut oil with an aflatoxin B1 content of 30 ppb. Take 50g of the above peanut oil and put it into a glass plate with a diameter of 10cm, and cover it with a cut-off optical glass with a diameter of 12cm and a thickness of 2mm, with a transmission limit wavelength of 200nm and a transmittance of 89.5%. Place the glass plate containing peanut oil in a pulsed strong light sterilization system, and keep the distance from the lamp to the oil surface at 5cm. Turn on the pulsed strong light, and after irradiating 30 pulses, take out the peanut oil to obtain peanut oil 4.

[0068] Comparative Example 2

[0069] Add aflatoxin B1 to the finished peanut oil to obtain peanut oil with an aflatoxin B1 content of 30 ppb. Take 50g of the above peanut oil and put it into a glass plate with a diameter of 10cm, and cover it with a cut-off optical glass with a diameter of 12cm and a thickness of 2mm, with a transmission limit wavelength of 330nm and a transmittance of 85%. Place the glass plate containing peanut oil in a pulsed strong light sterilization system, and keep the distance from the lamp to the oil surface at 10cm. Turn on the pulsed strong light, irradiate 60 pulses, and then take out the peanut oil to obtain peanut oil 5.

[0070] Comparative Example 3

[0071] Add aflatoxin B1 to the finished peanut oil to obtain peanut oil with an aflatoxin B1 content of 30 ppb. Take 50g of the above peanut oil and put it into a glass plate with a diameter of 10cm, and cover it with a cut-off optical glass with a diameter of 12cm and a thickness of 2mm, with a transmission limit wavelength of 340nm and a transmittance of 85%. Place the glass plate containing peanut oil in a pulsed strong light sterilization system, and keep the distance from the lamp to the oil surface at 10cm. Turn on the pulsed strong light, irradiate 60 pulses, and then take out the peanut oil to obtain peanut oil 6.

[0072] Comparative Example 4

[0073] Aflatoxin B1 was added to the finished peanut oil to obtain peanut oil with an aflatoxin B1 content of 30 ppb. 50 g of the above peanut oil was put into a glass plate with a diameter of 10 cm, and a cut-off optical glass with a diameter of 12 cm and a thickness of 2 mm was covered on the top, with a transmission limit wavelength of 380 nm and a transmittance of 86%. The glass plate containing the peanut oil was placed in a pulsed strong light sterilization system, and the distance from the lamp to the oil surface was kept at 5 cm. The pulsed strong light was turned on, and after irradiation for 30 pulses, the peanut oil was taken out to obtain peanut oil 7.

[0074] Comparative Example 5

[0075] Aflatoxin B1 was added to the finished peanut oil to obtain peanut oil with an aflatoxin B1 content of 30 ppb. 50 g of the above peanut oil was put into a glass plate with a diameter of 10 cm, and a cut-off optical glass with a diameter of 12 cm and a thickness of 2 mm was covered on the top, with a transmission limit wavelength of 300 nm and a transmittance of 89.5%. The glass plate containing the peanut oil was placed in a pulsed strong light sterilization system, and the distance from the lamp to the oil surface was kept at 20 cm. The pulsed strong light was turned on, and after 50 pulses were irradiated, the peanut oil was taken out to obtain peanut oil 8.

[0076] Comparative Example 6

[0077] Add aflatoxin B1 to the finished peanut oil to obtain peanut oil with an aflatoxin B1 content of 30 ppb. Take 50g of the above peanut oil and put it into a glass plate with a diameter of 10cm, and cover it with a cut-off optical glass with a diameter of 12cm and a thickness of 2mm, with a transmission limit wavelength of 300nm and a transmittance of 89.5%. Place the glass plate containing peanut oil in a pulsed strong light sterilization system, and keep the distance from the lamp to the oil surface at 8cm. Turn on the pulsed strong light, irradiate 70 pulses, and then take out the peanut oil to obtain peanut oil 9.

[0078] Comparative Example 7

[0079] Aflatoxin B1 was added to the finished peanut oil to obtain peanut oil with an aflatoxin B1 content of 30 ppb. 50 g of the above peanut oil was put into a glass plate with a diameter of 10 cm. The glass plate containing the peanut oil was placed in a pulsed strong light sterilization system with an open surface, and the distance from the lamp to the oil surface was kept at 8 cm. The pulsed strong light was turned on, and after irradiation for 40 pulses, the peanut oil was taken out to obtain peanut oil 10.

[0080] Comparative Example 8

[0081] Aflatoxin B1 is added to the finished peanut oil to obtain peanut oil with an aflatoxin B1 content of 30 ppb. 50 g of the above peanut oil is put into a glass dish with a diameter of 10 cm, and a visible light cutoff glass with a diameter of 12 cm and a thickness of 2 mm is covered on the top to filter the visible light of 400 nm-650 nm in the pulsed light spectrum. The glass dish containing peanut oil is placed in a pulsed light sterilization system, and the distance from the lamp to the oil surface is kept at 5 cm. Turn on the pulsed light, and after irradiating 30 pulses, take out the peanut oil to obtain peanut oil 11.

[0082] Comparative Example 9

[0083] Aflatoxin B1 was added to the finished peanut oil to obtain peanut oil with an aflatoxin B1 content of 30 ppb. 50 g of the above peanut oil was put into a glass dish with a diameter of 10 cm. The glass dish containing the peanut oil was placed in a 365 nm ultraviolet light source, and the distance from the lamp to the oil surface was kept at 5 cm. The ultraviolet lamp was turned on, and after irradiation for 10 seconds, the peanut oil was taken out to obtain peanut oil 12.

[0084] Comparative Example 10

[0085] Aflatoxin B1 was added to the finished peanut oil to obtain peanut oil with an aflatoxin B1 content of 30 ppb. 50 g of the above peanut oil was put into a glass dish with a diameter of 10 cm. The glass dish containing the peanut oil was placed in a 365 nm ultraviolet light source, and the distance from the lamp to the oil surface was kept at 5 cm. The ultraviolet lamp was turned on, and after irradiation for 87 minutes, the peanut oil was taken out to obtain peanut oil 13.

[0086] Comparative Example 11

[0087] Aflatoxin B1 is added to the finished corn oil to obtain corn oil with an aflatoxin B1 content of 30 ppb. 50 g of the corn oil is placed in a glass dish with a diameter of 10 cm, and a cut-off optical glass with a diameter of 12 cm and a thickness of 2 mm is placed on the top, with a transmission limit wavelength of 300 nm and a transmittance of 80%. The glass dish containing corn oil is placed in a pulsed strong light sterilization system, and the distance from the lamp to the oil surface is kept at 5 cm. Turn on the pulsed strong light, and after irradiating 40 pulses, take out the corn oil to obtain corn oil 2.

[0088] The main experimental conditions of Examples 1-4 and Comparative Examples 1-11 are shown in Table 1.

[0089] The irradiation dose, aflatoxin B1 content, aflatoxin B1 reduction rate (compared with before irradiation), acid value, peroxide value and flavor of the vegetable oils in Examples 1-4 and Comparative Examples 1-11 were measured and evaluated. The aflatoxin B1 content, acid value, peroxide value and flavor of the raw material reverse-added finished peanut oil, reverse-added finished corn oil and self-pressed peanut oil were measured and evaluated. The results are shown in Table 2.

[0090] Table 1: Experimental conditions of Examples 1-4 and Comparative Examples 1-11

[0091]

[0092]

[0093] *: The light source used in Comparative Examples 9 and 10 is ultraviolet light, so the irradiation condition is the irradiation duration rather than the number of pulses.

[0094] Table 2: Aflatoxin B1 content, aflatoxin B1 reduction rate, irradiation dose, acid value, peroxide value and flavor grade of vegetable oil in Examples 1-4 and Comparative Examples 1-11

[0095]

[0096]

[0097] As can be seen from Table 1 and Table 2, the method of the present invention can reduce the aflatoxin content in vegetable oil by more than 90%, while keeping the quality of the oil basically unaffected, and the processing time is extremely short, and Examples 1-4 only use 10-20s. The transmission limit wavelength of the cut-off optical glass used in Comparative Example 1 is lower than 280nm, and the quality of the vegetable oil is significantly affected. The transmission limit wavelength of the cut-off optical glass used in Comparative Examples 2-4 is higher than 320nm, and the aflatoxin removal rate is less than 90%. Comparative Example 9 shows that the aflatoxin content of the vegetable oil is almost unchanged after 10s of treatment with 365nm ultraviolet light. Comparative Example 10 shows that the aflatoxin content of the vegetable oil can be reduced to the level of the method of the present invention only after 87min of treatment with 365nm ultraviolet light, and the quality of the oil is significantly affected. Although the transmission limit wavelengths of Comparative Examples 5 and 11 are within the scope of the present invention, due to the low irradiation dose, the reduction in the aflatoxin content does not reach the level required by the present invention.

Claims

1. A method for removing aflatoxin from vegetable oil, characterized in that: The method comprises using a pulsed intense light with a minimum wavelength between 280nm and 320nm at 11J / cm 2 -40J / cm 2 The step of irradiating the vegetable oil containing aflatoxin with a radiation dose of, the irradiation time is 6 seconds to 20 seconds, wherein the vegetable oil is peanut oil and / or corn oil.

2. The method according to claim 1, characterized in that The vegetable oil receives 30-60 pulses of the intense pulse light.

3. The method according to claim 1 or 2, characterized in that The pulse width of the pulsed intense light is between 340 μs and 380 μs, and / or the pulse frequency of the pulsed intense light is 2-5 pulses / second.

4. The method according to claim 1 or 2, characterized in that: The thickness of the vegetable oil on one side in the direction irradiated by the strong pulse light is 0.5 cm to 1 cm.

5. The method according to claim 1, characterized in that A cut-off optical glass with a transmission limit wavelength between 280nm and 320nm is arranged between the pulse strong light source and the vegetable oil, so that the vegetable oil is irradiated by the pulse strong light with a minimum wavelength between 280nm and 320nm.

6. The method according to claim 5, characterized in that The distance between the light source and the vegetable oil is selected according to the transmittance of the cut-off optical glass, the pulse width and the pulse frequency of the pulsed strong light, so that the vegetable oil receives 11 J / cm within 6 seconds to 20 seconds. 2 -40J / cm 2 of radiation dose.

7. Aflatoxin-free vegetable oil prepared by the method according to any one of claims 1 to 6.

8. Use of pulsed intense light with a minimum wavelength between 280nm and 320nm in removing aflatoxin from vegetable oils, with an irradiation dose of 11J / cm 2 -40J / cm 2 The irradiation time is 6 seconds to 20 seconds, and the vegetable oil is peanut oil and / or corn oil.

Images