Note that the direct contact area between chopped vegetables and water increases many times, which will increase the water-soluble vitamins in the vegetables, such as vitamin B, vitamin C, some minerals, and some water-soluble sugars. The species will dissolve in water and be lost. At the same time, chopping vegetables will increase the chance of being contaminated by bacteria on the vegetable surface, leaving health risks. Therefore, vegetables should not be cut first and then washed, but should be washed first and then cut.

1. Soaking in light salt water: Generally, vegetables are washed with water at least 3 to 6 times, then soaked in light salt water, and then rinsed once with water. For stuffed vegetables, you can cut them first, soak them in clean water for 1 to 2 hours, and then rinse them with clean water to remove residual pesticides.

2. Alkali washing: To wash vegetables with alkali, first put a pinch of alkali powder, anhydrous calcium carbonate or icy alkali, and crystalline sodium carbonate in the water, stir well, then add the vegetables and soak for 5 ~6 minutes, pour out the alkaline water, and then rinse with clean water. Baking soda can also be used instead, but the soaking time should be extended appropriately, usually about 15 minutes.

3. Wash with dish soap: Dilute the dish soap to 300 times and wash once, then rinse with water 1 to 2 times. This can remove bacteria, insect eggs and residual pesticides on the vegetables. .

4. Soak in boiling water: The best way to remove some residual pesticides is to scald them, such as green peppers, cauliflower, beans, celery, etc. It is best to blanch them in boiling water before putting them in the pot. According to tests, this method can remove 90% of residual pesticides.

5. Disinfection with sunlight: Using the multi-spectral effect of sunlight to illuminate vegetables will cause some residual pesticides in the vegetables to be decomposed and destroyed. It has been determined that when vegetables and fruits are exposed to sunlight for 5 minutes, 60% of the residual amounts of organochlorine and organomercury pesticides are lost. For vegetables that are easy to store, it is best to leave them for a period of time. The oxygen in the air and the color enzymes in the vegetables have a certain decomposition effect on residual pesticides. Therefore, after purchasing vegetables, you should store them at room temperature for about 24 hours, so that the average disappearance rate of residual chemical pesticides is 5%.

6. Wash vegetables with rice washing water: Washing vegetables with rice washing water can remove some pesticides remaining in vegetables. Because most of our country currently uses methamidophos, phoxim, dichlorvos, dimethoate and other organophosphorus pesticides to kill insects, these pesticides will lose their toxicity when exposed to acidic substances. Soaking in rice washing water for about 10 minutes and washing with clean water can reduce pesticide residues in vegetables.