In modern life, fruits and vegetables are an important part of our daily diet, and their safety issues are increasingly attracting people's attention. Pesticide residue problem, as a major hidden danger to the safety of fruits and vegetables, is even more worrying. The abuse and overuse of pesticides have led to serious pesticide residues exceeding the standard after-harvest fruits, including organophosphorus pesticides such as aminethion, chlorpyrifos, propyl bromophen and triazophen, which have been explicitly prohibited by the state. Long-term intake of these residual substances may cause potential harm to human health.

The famous independent environmental protection organization EWG (American Environmental Work Organization), every year, sorts out the "Dirty Fruit and Vegetable Ranking" and "Clean Fruit and Vegetable Ranking" based on pesticide residues of vegetables and fruits. In 2023, EWG analyzed the detection data of 46,569 samples from 46 vegetables and fruits, and ranked the annual list. We sorted out the top 12 with the most pesticide residues and the top 15 with the most pesticide residues.

2023 EWG's most dirty fruits and vegetables rankings

2023 EWG's best clean fruits and vegetables rankings

So, how to effectively clean fruits and vegetables and remove pesticide residues? Common and practical fruit and vegetable cleaning methods are as follows: 1. Soaking and cleaning method. Soaking fruit and vegetable cleaning method is a simple and common fruit and vegetable cleaning method. Soaking fruit and vegetable in clean water for 30 minutes to 1 hour will help dissolve some pesticides. 2. Add salt to clean the method. Based on the soaking and cleaning method, we can add an appropriate amount of salt to help dissolve some pesticides. 3. Baking soda cleaning method. When cleaning fruits and vegetables, we can dilute the baking soda and water at a ratio of 1:10, and then soak the fruits and vegetables in the diluted baking soda solution for 5-10 minutes. Some pesticides will fail in alkaline environments. 4. Fruit and Vegetable Cleaning Agents There are many cleaning agents on the market that are specially used for cleaning fruits and vegetables. These cleaning agents contain various ingredients such as surfactants, emulsifiers, flavors and pigments, and usually have multiple effects such as decontamination, sterilization, and removal of pesticide residues. However, it should be noted that the cleaning agent itself is a petrochemical raw material. If the cleaning is not thorough, some cleaning agent will easily remain. The harmful substances that may remain in detergents will directly enter the human body through the digestive tract during the diet, posing safety hazards to people's health. So is there a fruit and vegetable cleaning product that can efficiently remove fruit and vegetable pesticide residues and is safe and harmless to the human body? In recent years, electrolytic functional water has attracted widespread attention at home and abroad as a rising star in the field of cleaning and sterilization. Electrolytic water is divided into two categories: Acidic electrolyzed water (AEW) and alkaline electrolyzed water (BEW). The electrolytic function water has high biosafety. Experts and scholars at home and abroad conducted experiments on skin irritation and cytotoxicity on mice, mammals and human volunteers, and found that there was no obvious change in the various indicators of the experimental subject. In addition, ultra-alkaline/strong alkaline electrolytic water has the characteristics of efficient removal of pesticide residues on the surface of fruits and vegetables, ensuring the quality of fruits and vegetables, and being harmless to the environment.

Liu Lilan from Southwest University of Science and Technology conducted research on the process of removing organic phosphorus pesticide residues on the surface of fruits by electrolyzing water:

The experimentalists used acidic electrolytic water (AEW) stock liquid to be used: pH 2.40±0.16, ORP 1147.33±5.06 mV, effective chlorine concentration 20 mg/L; alkaline electrolytic water (BEW) stock liquid to be used: pH 12.65±0.26, ORP -850±5.89 mV. Experimental design: - Effect of different detergents on the removal of pesticide residues in citrus. Set 6 treatments: purified water, 0.05 mL/L dish soda, 2 g/L baking soda, 1:10 (V/V) alkaline electrolytic water (BEW), 1:10 (V/V) acidic electrolytic water (AEW), etc., and after soaking at room temperature for 3 minutes, the enzyme inhibition rate was compared.     - Single-factor experimental design examined the effects of alkaline electrolytic water dilution ratio (1:1, 1:5, 1:10, 1:20, 1:40), treatment time (1, 2, 4, 8, 10 min) treatment volume (100, 200, 300, 400, 500 mL) on enzyme inhibition rate respectively.     - Response surface design Based on the single-factor experimental results, the response surface was designed by the Box-Behnken method, and the enzyme inhibition rate (Y) was used as the response value. Three factors, namely alkaline electrolytic water dilution ratio (A), treatment time (B) and treatment volume (C), were selected to analyze the response surface (3 factors and 3 levels). The experimental design is shown in Table 1.

Results and analysis: ① Comparison of the removal effects of 6 detergent treatments on citrus pesticide residues: The removal effects of 6 detergent treatments on citrus pesticide residues are shown in Figure 1. Compared with the control, 6 detergent treatments can significantly remove pesticide residues on the surface of citrus (P<0.001). The order of removal effects from strong to weak is 1:10 BEW>2 g/L salt water>pure water>1:10 AEW>0.05 mL/L dish soda water>2 g/L baking soda water. Among them, when August oranges were washed with 0.05 mL/L dishwashing and 2 g/L baking soda water, the average enzyme inhibition rate was 45.78% and 48.63% respectively, and the pesticide residue exceeded the standard, indicating that neither of these two detergent treatments were suitable for the pesticide residue removal of this kind of citrus. 1:10 BEW and 2 g/L saline water can significantly remove pesticide residues on the surface of August orange. Compared with the control group, the enzyme inhibition rate decreased by 72.44% and 67.69%, respectively. It can be seen that 1:10 BEW is the best washing method to remove pesticide residues on the surface of citrus.

② Optimize the process of removing pesticide residues in alkaline electrolytic water surface by alkaline electrolytic water: The three factors and three horizontal response surface optimization experiments were designed using the Box-Behnken design principle. The response surface optimization experiment was optimized using the alkaline electrolytic water dilution ratio (A), treatment time (B) and treatment volume (C) as independent variables, and the enzyme inhibition rate (Y) as the response value. A total of 17 experimental plans were designed, including 5 groups of central experimental points, each group of tests was repeated 3 times, and the average value of the three repetitions was taken. The response surface optimization results were shown in Table 2.

③Response surface interaction analysis Response surface method is a technology that sets statistics and experimental design, used to determine the relationship and influence of selected variables on specific response values. The simulated response surface diagram and corresponding contour diagram were obtained according to the regression equation, and the influence of dilution ratio, processing time and processing volume on enzyme inhibition rate was determined. The response surface diagram and contour diagram were shown in Figures 5~7.

Conclusion: (1) Compared with other detergent treatment methods, alkaline electrolytic water (BEW) can significantly remove pesticide residues on the surface of citrus. (2) The treatment process conditions after model optimization are dilution ratio 1: 8.49, immersion time 1.26 min, immersion volume is 388.45 mL, and enzyme inhibition rate is 40%. After verification, the enzyme inhibition rate was obtained at 40.59%, indicating that alkaline electrolytic water has good ability to remove organic phosphorus pesticide residues on the surface of fruits and vegetables under this treatment process conditions.

Fangxin super alkaline/strong alkaline electrolytic water has good cleaning effect and can be used as a substitute for harmful chemical cleaning agents. The waste liquid after use can be directly discharged after separation of oil and water, which is free of pollution to the environment and is not subject to the restrictions of VOC rules and environmental protection policies. The super alkaline/strong alkaline electrolytic water of Fangxin can not only be used in the cleaning and removal of pesticide residues in fruits and vegetables, but can also be used in industrial cleaning, oil removal and rust prevention, CIP pipeline cleaning, optical lenses, liquid crystal panels and other precision cleaning fields, as well as the extraction of tea, coffee plant protein, etc. (does not destroy the original ingredients and flavor of the extract), replace pesticides and fertilizers, and promote plant growth. Over the years, our customer base has spanned more than 40 countries and regions on six continents around the world. The application scenarios include traditional industry and trade and emerging industries, and have cooperated with many well-known domestic and foreign companies to achieve gratifying results in industries such as metal parts cleaning. Fangxin super alkaline/strong alkaline electrolytic water-lysis equipment has won unanimous recognition from customers for its high intelligence and high quality! Our alkaline water indicators have been tested by 106 items by SGS and merieux NutriSciences, which are non-toxic and harmless, and meet food safety standards. In addition, due to its high pH value, the super alkaline/strong alkaline electrolytic water can hydrolyze the proteins and nucleic acids of pathogenic bacteria, destroy the normal metabolic functions of bacteria, and cause bacteria to die, so as to achieve physical bactericidal effect.

(Customer product of Fangxin Super Alkaline Electrolytic Water Equipment)

(Customer product of Fangxin Super Alkaline Electrolytic Water Equipment)

(Fangxin super alkaline electrolytic water-lysis equipment is used in the field of industrial cleaning)

With the increasing global awareness of environmental protection, the demand for green and environmentally friendly cleaning agents is growing rapidly in all industries. As a leader in the field of industrial cleaning, Fangxin electrolytic water-lysis equipment stands out with its independent core technology that is superior to the industry and its stable and reliable practical performance, providing many customers with green and efficient cleaning solutions.

In the future, Fang Xin will continue to increase R&D investment and continue to launch more innovative and competitive electrolytic water-lysis equipment. At the same time, Fang Xin will also actively expand the international market and work with partners around the world to promote the application and development of green and environmentally friendly cleaning agents. In this process, Fang Xin will work hand in hand with friends from all walks of life with a more open mind and a pragmatic style to jointly promote the greening and sustainable development of the industrial and agricultural cleaning field.     Note: The experimental content of this article is from "China Agricultural Science Bulletin 2022, 38(2):133-140" and "Research on the Process of Removing Organophosphorus Pesticide Residues on Fruits with Alkaline Electrolyzed Water". The content of this article is for the purpose of conveying more information and is for reference only by readers. If there is any infringement of the relevant content, please notify us. Reproduction may not be made without permission.