Pesticide residue is a major problem in the fruit and vegetable session, China’s annual consumption of pesticide-contaminated food poisoning caused by the number of people reached about 200,000, accounting for about one-third of the number of food poisoning, and long-term intake of excessive pesticide will cause harm to multiple systems of the human body.
Many people are used to soaking vegetables for a period of time after washing them to remove pesticide residues, and some will extend the soaking time to 3-4 hours or even overnight to achieve better results. But do you know, this seemingly healthy behavior, not only will reduce the nutrient content of vegetables, and may even make the dish more “dirty” soak.
Soaking time the longer the better?
According to the dissolution properties to be divided, pesticides can be divided into water-soluble and fat-soluble two. Water-soluble pesticides are mainly trichlorfon, vinblastine, insecticide double, etc.; fat-soluble pesticides are mostly organophosphorus pesticides, such as lewisite, lewisite oxide, etc..
At present, most of the pesticides used in fruits and vegetables are mainly fat-soluble pesticides, because the permeability of fat-soluble pesticides is much greater than that of water-soluble pesticides, its control effect will be much better than water-soluble pesticides. But at the same time, this phenomenon also causes the residues of fat-soluble pesticides on the surface of fruits and vegetables is much higher than water-soluble pesticides.
The traditional method of soaking with water, can only remove water-soluble pesticides on the surface of fruits and vegetables, but can not remove their main residues – fat-soluble pesticides. And in the soaking process, water-soluble pesticides will dissolve in the water and the formation of a certain concentration of aqueous solution, if soaked for too long, it is likely to lead to the water pesticides are re-absorbed by the fruits and vegetables.
In addition, if the soaking time is too long, it will also cause many water-soluble nutrients in vegetables such as vitamin C, vitamin B, as well as calcium, magnesium, iron, zinc, etc. dissolved in water thus causing the loss of its nutrients. Someone once did a related study found that when the vegetable soaking time more than 15 minutes, the vitamin C content loss rate of more than 90%.
Therefore, this method of soaking fruits and vegetables in water for a long time is not scientific, not only can not improve the removal rate of pesticide residues, and may even cause fruits and vegetables to re-absorb pesticide residues and nutrient loss.
How to remove pesticide residues correctly?
So, the traditional soaking method is not feasible, and how can we properly remove pesticide residues?
1. blanching: blanching vegetables for 1-1.5 minutes after washing can remove most of their fruit and vegetable residues, and will not cause too much loss of nutrients to vegetables. Take vegetable heart for example, rinsing with water can only remove 30% of its residual methamidophos content, while blanching for 1 minute can go more than 90%.
2. Peeling: For some fruits that cannot be blanched and vegetables with thicker skin (such as cucumbers, radishes, etc.), you can remove pesticide residues by peeling. General pesticide residues only on the surface of the fruit, the pesticide removal rate of the peeling method can reach more than 90%.
3. Weak alkaline water rinsing: common weak alkaline water in the kitchen are mainly rice water, flour water and baking soda water. The vast majority of pesticides in alkaline conditions are easy to decompose, so the use of such weak alkaline water rinsing fruits and vegetables, the pesticide residue removal rate is slightly higher than ordinary water.
4. live water rinse: live water rinse fruits and vegetables instead of long time soaking fruits and vegetables, not only can improve the removal rate of pesticide residues, and will not cause a large loss of nutrients. At the same time, we also remind everyone in the cleaning of vegetables must be washed after cutting to ensure the integrity of vegetables, so that not only can prevent the pesticides dissolved in water through the cut surface of vegetables penetrate into the vegetable interior, but also effectively prevent the loss of its water-soluble nutrients dissolved or oxidation loss.
5. clever cleaning with detergent: water washing can remove most of the water-soluble pesticide residues, but for fat-soluble pesticide residues, we need to use the role of detergent. When washing fruits and vegetables, add 1-2 drops of edible detergent in the soaking water and soak for 3-5 minutes, followed by 1-2 rinses with water to remove most of the fat-soluble pesticide residues.
How to select vegetables with low residue amount?
In addition to learning how to wash fruits and vegetables, we should also learn how to select fruits and vegetables with low residue amounts to reduce the intake of pesticides from the source.
1. Choose fruits and vegetables from regular sources
Most of us will choose meat products from regular sources, but often do not have this concept when buying fruits and vegetables. In fact, fruits and vegetables in large supermarkets/farmers’ markets/fruit supermarkets will undergo more stringent pesticide residue testing, and there will be occasional market sampling during the sales process. Generally speaking, their pesticide residues will be lower and more stable than those sold by ordinary vendors.
2. Look at the appearance
We do not recommend that consumers buy too bright-looking fruits and vegetables, such fruits and vegetables may be due to the spraying of excessive pesticides, resulting in a more attractive appearance; but at the same time, we also do not recommend that consumers buy “pesticide-free” vegetables with insect eyes, such vegetables are not necessarily no pesticides, but pests and diseases occur only after the drug, this type of These vegetables not only have pesticide residues, the pesticide is also very likely to penetrate into the vegetable through the insect eye, causing its pesticide residues to seriously exceed the standard. Overall, consumers in the purchase of fruits and vegetables, choose the right degree of maturity, color and appearance of normal fruits and vegetables can be.
3. smell
Before buying, you can smell it, if the vegetable smell is abnormal, slightly pungent smell is not to buy, which may be due to a large number of pesticide residues with a pungent taste caused. For bean sprouts, mushrooms and other food, if the color is white, and has a pungent smell, it is likely to be bleached through sulfur dioxide fumigation, long-term consumption of such bleached food is harmful to the human body, it is recommended that consumers do not buy.
