Soaking vegetables in salt water does not remove chemicals but you should still do it

Soaking vegetables in salt water before processing and using is a common habit among many families. This has been passed from generation to generation, with a belief that it will eliminate pesticide residues and preservative chemicals in fruits and vegetables. So how is the story really wrong? Is this simple method so effective?

Is soaking vegetables in salt water effective?

Soak salt water not to remove chemical drugs

In fact, the use of salt to clean and preserve food has appeared thousands of years ago. Tips for washing food with salt have also been passed down for a long time.

Meanwhile, the use of chemicals in agriculture has really exploded in the 1940s. Until the middle of the 20th century, both consumers and policy makers were not too concerned about health risks. latent in the use of pesticides. Farmers know that they have a better crop. On the consumer side, they buy cheaper food.

So it is clear that soaking vegetables in salt water is a folk experience , even before we worry about the harmful effects of agricultural chemicals. Its original purpose is not to eliminate pesticides or preserve food.

So what do salt water do?

Experience of soaking vegetables with salt water starting from the period of agricultural cultivation has not been modernized. At that time, the use of organic fertilizer is very common. It is a condition for many types of bacteria, such as E. coli, Coliforms or Salmonella, which contaminate soil, water and agricultural products.

The result is mild, eating infected vegetables causes diarrhea and severe poisoning and death. Soaking salt water becomes a simple method to solve this problem. Although it may not have been clear in the past, the salt water mechanism could kill bacteria.

Soaking vegetables in salt water helps kill pathogenic bacteria.

Today, science can explain that. All microorganisms have a semi-permeable membrane, which will withstand a osmotic pressure so that water moves into and out of the cell. Water will move from high concentrations to low concentrations.

When bacteria are immersed in salt water, their cell water concentration is higher. Water will be drained to the outside, microorganisms will shrink and die. Spores in this case are not killed, but they cannot grow.

Thus, soaking vegetables in salt water has the effect of removing harmful bacteria . It is a very simple but useful measure, especially when you buy agricultural products in areas where traditional practices are used, using organic fertilizers.

There is no effect on chemicals

In fact, soaking vegetables in salt water can make them safer from bacteria, but it has almost no effect on pesticides or preservatives that remain on it. In an interview on this issue, Associate Prof. Dr. Nguyen Duy Thinh, lecturer of the Department of Food Technology, Hanoi University of Technology said:

" Many people use salt water to kill bacteria in meat, fish for a long time, have a slight odor or soak fruits and vegetables when buying in the market. This work only works to inhibit or kill bacteria to a certain extent. But not all chemicals, but the pesticide and salt water chemicals do not work as many people believe . "

Adding salt to the soaked water does not help eliminate chemical residues in fruits and vegetables.

Master, Dr. Le Thi Hai, Director of the Nutrition Advisory Center, National Institute of Nutrition, also affirmed that salt water cannot help eliminate chemical residues of food protection drugs on vegetables.

Agricultural chemical products such as pesticides are often derived from petroleum. Like these chemical products, they are not soluble in water. So, soaking vegetables and fruits, even in salt water, cannot remove pesticides from food.

Types of specialized vegetable washes

As mentioned, water and even salt water do not help dissolve pesticide residues on fruits and vegetables. On the market, there are also some types of water dedicated to washing fruits and vegetables. However, their effectiveness is very limited, according to a study by Pham Ngoc Thach Medical University, Ho Chi Minh City.

In the same view, the Associate Professor, Dr. Ngo Quoc Quyen, Institute of Chemistry, Vietnam Academy of Science and Technology also affirmed that it is impossible to have any kind of cleansing to ensure absolute clean vegetables . If water used to wash fruits and vegetables using substances such as deionized water . only has antiseptic, antiseptic properties, but is not capable of cleaning, but if using chemical substances for cleaning, it is likely that causing bad effects.

Principles for washing fruits and vegetables

In principle, washing fruits and vegetables before use to disappear all risks to human health. The two most common risks you can see are bacteria and residues of agricultural chemical preparations.

While pesticides cannot be dissolved and stored with either normal or salt water, you can remove them by mechanical means. Specifically, rinse several times under running water , thoroughly clean the cloth outside their shell . Research shows that 75-85% of pesticides can be removed by washing and wiping only with cold water.

More than 80% of pesticide residues can be removed only by thorough washing under running water.

Another measure is to blanch in hot water . The Indian National Institute of Nutrition recommends that this applies to most vegetables. The amount of pesticides can be effectively eliminated in this way. However, the previous washing process is still very important.

For fruits, pesticides are basically covered on their surface. So, after thoroughly washing, peeling is an important step to eliminate this.

Processing at high temperatures will be the last step to destroy the persistent bond of chemicals on food. It not only works with fruits and vegetables, but also works with animal products such as meat, fatty tissue or milk.

Here is the procedure for vegetables and fruits, recommended by Dr. Cao Thi Hau, former Director of National Nutrition Institute:

1. Soak vegetables in clean water for 5-10 minutes to wash or use rice water to soak, aiming to neutralize toxins in pesticides.

2. Use 5% salt water to wash vegetables.

3. Cucumbers, eggplant or fruits with a high concentration of pesticides are best washed, peeled and eaten.

4. Heating at high temperatures also causes pesticide resolution, some heat-resistant vegetables such as cauliflower, beans, vegetables need . after washing, blanching with hot water for 2 minutes makes the amount of medicine 30% reduction in insecticides, then cooking at high temperatures, thus eliminating 90% of pesticides.

5. Sunlight makes the amount of pesticides on vegetables broken, resolved. For vegetables in the sun for 5 minutes, the amount of pesticides left on vegetables such as organic mercury, organic chlorine reduced by about 60%.