Method for reducing pesticide residues on fruits and vegetables

Abstract

The invention relates to the technical field of pesticide residue degradation, and discloses a method for reducing pesticide residues of fruits and vegetables, which comprises the following steps: placing the fruits and vegetables in a mixed gas atmosphere for sealed storage; the mixed gas comprises methane and auxiliary gas; the volume percent of methane in the mixed gas is 0.1%-4%; the auxiliary gas comprises at least one of air, nitrogen and carbon dioxide; the storage means that the temperature is not higher than 35 DEG C and the humidity is not higher than 70%. The method can reduce pesticide residues in fruits and vegetables, has the characteristics of no residues, low cost and simplicity and convenience in operation, has the characteristic of safety due to the fact that the concentration of gas fumigation methane is lower than the explosion limit by 4.9%, and can be widely applied to reduction of pesticide residues in various fruits and vegetables, such as tomatoes, strawberries, pears and hot peppers.

Description

Technical Field

[0001] The invention belongs to the technical field of pesticide residue degradation, and in particular relates to a method for reducing pesticide residues in fruits and vegetables. Background Art

[0002] Pesticide residues refer to the undecomposed pesticide precursors, intermediates, metabolites, etc. that remain on the surface of fruits and vegetables or penetrate into the interior after they are sprayed with pesticides to increase yields during their growth. If agricultural products with excessive pesticide residues are consumed for a long time, harmful substances will accumulate in the body, causing chronic poisoning or even death.

[0003] Therefore, it is imperative to find a suitable and safe method to reduce the risk of pesticide residues while maintaining pest control. Today, there are biological, chemical and physical methods to reduce pesticide residues, among which biological methods include microorganisms, genetically engineered bacteria and enzyme catalysis; chemical methods include oxidation and photochemical degradation; physical methods include cleaning, adsorption, ultrasonic and the like. Biological methods are safe and non-toxic, but time-consuming and costly; although chemical methods have good degradation effects, they may cause secondary pollution to the environment, and some strong oxidizing substances may destroy the surface morphology of fruits and vegetables, causing loss of nutritional quality; physical methods are simple and easy to operate, and cleaning methods are the most convenient, low-cost, and will not pollute the environment, and can be used in daily life. However, the traditional gas conditioning degradation efficiency is low, and there may be a risk of pesticide residues. Therefore, developing a safe, efficient, green and pollution-free gas conditioning method is a research hotspot in this field. The present invention utilizes methane, which has a certain permeability, is non-toxic, harmless and tasteless, and places fruits and vegetables in a closed container containing methane for treatment to achieve the effect of degrading pesticide residues.

[0004] In view of this, the present invention is proposed. Summary of the invention

[0005] In order to solve the above technical problems, the basic concept of the technical solution adopted by the present invention is:

[0006] A method for reducing pesticide residues in fruits and vegetables comprises placing the fruits and vegetables in a mixed gas atmosphere for sealed storage; the mixed gas comprises methane and auxiliary gas.

[0007] As a preferred embodiment of the present invention, the volume percentage of methane in the mixed gas is 0.1% to 4%.

[0008] As a preferred embodiment of the present invention, the auxiliary gas includes at least one of air, nitrogen and carbon dioxide.

[0009] As a preferred embodiment of the present invention, the storage refers to storage at a temperature not higher than 35° C. (including 35° C.) and a humidity not higher than 70% (including 70%).

[0010] Compared with the prior art, the present invention has the following beneficial effects:

[0011] 1. Clean and green: It is colorless and odorless, and will not discolor the shells of fruits and vegetables. Low concentrations of methane have stable chemical properties, will not burn or explode, and will not have adverse effects on the human body or the environment.

[0012] 2. Convenient transportation: Methane has a high liquefaction temperature and is easy to liquefy, store and transport.

[0013] 3. Convenient and low-cost: The preparation of methane is simple and low-cost. Methane can be synthesized from gas or through biological methods.

[0014] 4. Wide range of applications: applicable to most fruits and vegetables on the market. DETAILED DESCRIPTION

[0015] The following is a detailed description of the preferred embodiments of the present invention so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby making a clearer and more definite definition of the protection scope of the present invention.

[0016] The pesticide residues in each treatment group and control group in this specific example were determined by the following method. The methane, nitrogen and carbon dioxide used in the example were purchased from Bengbu Lianhua Industrial Gas Co., Ltd. with a purity of 99.99%;

[0017] The determination of pesticide residues refers to "Guo Zheng, Li Yufei, Wu Xiaming, et al. Study on the attenuation of pesticide residues in fruits and vegetables under different storage conditions. Food Safety Guide, 2023(28): 98-104."

[0018] A method for reducing pesticide residues in fruits and vegetables, comprising methane with a concentration of 0.01% to 4% (v / v), and the rest being auxiliary gas. The concentration of the methane is 0.01% to 4%. The auxiliary gas comprises at least one of air, nitrogen, and carbon dioxide. The humidity of the environment in which the fruits and vegetables are stored is not higher than 70% (including 70%). The temperature at which the fruits and vegetables are stored is not higher than 35°C (including 35°C).

[0019] Example 1: Reducing the accumulation of pesticide residues in tomatoes

[0020] Fresh tomatoes purchased from Fengyang Vegetable Market were used as materials. 120 tomatoes were randomly divided into 4 groups and sprayed with several pesticides commonly used in tomatoes. After the sprayed pesticides were completely volatilized, they were placed in sealed containers. The control group was fumigated with air, and the treatment group was fumigated with methane gas of different concentrations at room temperature of 20°C and humidity of 60%. The pesticide residues were tested after 5 days:

[0021] Control group: air;

[0022] Treatment group 1: a mixture of air and methane, with a methane concentration of 1%;

[0023] Treatment group 2: a mixture of air and methane, with a methane concentration of 2%;

[0024] Treatment group 3: a mixture of air and methane, with a methane concentration of 3%;

[0025] Table 1. Effects of different methane concentrations on pesticide residues in tomatoes

[0026]

[0027] The experimental results showed that the pesticide residue removal rate of the treatment group was higher than that of the control group, indicating that methane fumigation has a good degradation effect on tomato pesticide residues.

[0028] Example 2: Reducing the accumulation of pesticide residues in strawberries

[0029] Fresh strawberries purchased from Fengyang Fresh Fruit Garden were used as materials. 240 strawberries were randomly divided into 4 groups and sprayed with several commonly used pesticides in strawberries. After the sprayed pesticides were completely volatilized, they were placed in sealed containers. The control group was fumigated with air, and the treatment group was fumigated with methane gas of different concentrations at room temperature of 4°C and humidity of 50%. The pesticide residues were tested after 7 days:

[0030] Control group: air;

[0031] Treatment group 1: a mixture of air and methane, with a methane concentration of 0.1%;

[0032] Treatment group 2: a mixture of air and methane, with a methane concentration of 0.5%;

[0033] Treatment group 3: a mixture of air and methane, with a methane concentration of 1%;

[0034] Table 2. Effects of different methane concentrations on pesticide residues in strawberries

[0035]

[0036] The experimental results showed that the pesticide residue removal rate of the treatment group was higher than that of the control group, indicating that methane fumigation promoted the degradation of strawberry pesticide residues.

[0037] Example 3: Reducing the accumulation of pesticide residues in snow pear

[0038] Fresh snow pears purchased from Fengyang Fresh Orchard were used as materials. 120 snow pears were randomly divided into 4 groups and sprayed with several commonly used pesticides in snow pears. After the sprayed pesticides were completely volatilized, they were placed in sealed containers. The control group was fumigated with air, and the treatment group was fumigated with methane gas of different concentrations at room temperature of 35°C and humidity of 30%. The pesticide residues were tested after 4 days:

[0039] Control group: nitrogen;

[0040] Treatment group 1: a mixture of nitrogen and methane, with a methane concentration of 0.01%;

[0041] Treatment group 2: a mixture of nitrogen and methane, with a methane concentration of 0.1%;

[0042] Treatment group 3: a mixture of nitrogen and methane, with a methane concentration of 1%;

[0043] Table 3. Effects of different methane concentrations on pesticide residues in snow pear

[0044]

[0045] The above results show that after methane gas fumigation, the pesticide residue removal rate in the treatment group was higher than that in the control group, indicating that methane fumigation can promote the degradation of pesticide residues in snow pear.

[0046] Example 4: Reducing the accumulation of pesticide residues in chili peppers

[0047] Fresh chili peppers purchased from Fengyang Vegetable Market were used as materials. 360 chili peppers were randomly divided into 4 groups and sprayed with several commonly used pesticides in chili peppers. After the sprayed pesticides were completely volatilized, they were placed in sealed containers. The control group was fumigated with air, and the treatment group was fumigated with methane gas of different concentrations at room temperature of 35°C and humidity of 70%. The pesticide residues were tested after 1 day:

[0048] Control group: carbon dioxide;

[0049] Treatment group 1: a mixture of carbon dioxide and methane, with a methane concentration of 3%;

[0050] Treatment group 2: a mixture of carbon dioxide and methane, with a methane concentration of 3.5%;

[0051] Treatment group 3: a mixture of carbon dioxide and methane, with a methane concentration of 4%;

[0052] Table 4. Effects of different methane concentrations on pesticide residues in chili peppers

[0053]

[0054] The experimental results showed that the pesticide residue removal rate in the treatment group was significantly higher than that in the control group, indicating that methane has a certain effect on the degradation of pesticide residues in chili peppers.

[0055] In summary, the method of reducing pesticide residues in fruits and vegetables of the present invention is not only clean, but also more environmentally friendly, colorless and odorless, and will not fade the shells of fruits and vegetables. Low-concentration methane has stable chemical properties, will not burn or explode, and will not have adverse effects on the human body or the environment.

[0056] The method for reducing pesticide residues in fruits and vegetables is convenient for transportation: methane has a high liquefaction temperature, is easy to liquefy, and is easy to store and transport.

[0057] The method for reducing pesticide residues in fruits and vegetables is convenient and low-cost: the methane preparation operation is simple and low-cost, and methane can be synthesized through gas or through biological methods.

[0058] The method for reducing pesticide residues in fruits and vegetables of the present invention has a wide range of applications: it can be applied to most fruits and vegetables on the market. It can be understood that the present invention is described through some embodiments, and those skilled in the art are aware that various changes or equivalent substitutions can be made to these features and embodiments without departing from the spirit and scope of the present invention. In addition, under the teachings of the present invention, these features and embodiments can be modified to adapt to specific circumstances and materials without departing from the spirit and scope of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed herein, and all embodiments that fall within the scope of the claims of this application belong to the scope protected by the present invention.

Claims

1. A method for reducing pesticide residues in fruits and vegetables, characterized in that: The fruits and vegetables are placed in a mixed gas atmosphere for sealed storage; the mixed gas includes methane and auxiliary gas.

2. The method for reducing pesticide residues in fruits and vegetables according to claim 1, characterized in that: The volume percentage of methane in the mixed gas is 0.1% to 4%.

3. The method for reducing pesticide residues in fruits and vegetables according to claim 1, characterized in that: The auxiliary gas includes at least one of air, nitrogen and carbon dioxide.

4. The method for reducing pesticide residues in fruits and vegetables according to claim 1, characterized in that: The storage refers to storage at a temperature not higher than 35° C. (including 35° C.) and a humidity not higher than 70% (including 70%).

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