Blanching is one of the cooking methods commonly used in our family, but in life, some vegetables can be fried directly in the pot without blanching, but some vegetables come with "poisons", if you omit the blanching step, it may bring danger! So which vegetables come with "poisons" that need to be blanched before stir-frying?
Don't worry, the editor will take you to find out
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"Dangerous molecules" in vegetables
4. Saponins: Saponins have strong irritation to the human digestive tract, can cause hemorrhagic inflammation, and have a lytic effect on red blood cells. When ingested in large quantities, saponins can irritate the gastrointestinal tract, causing vomiting, abdominal pain, and diarrhea.
5. Cyanogenic glycosides: Cyanogenic glycosides are also a plant toxin that exists in about 2,000 species of plants. Cyanogenic glycosides themselves are not toxic, but after the rupture of plant cells, cyanogenic glycosides will be partially converted into hydrocyanic acid, which may cause poisoning, resulting in shortness of breath, decreased blood pressure, dizziness, headache, stomach pain, vomiting, abdominal pain, diarrhea and other poisoning reactions, and may even lead to death in severe cases.
6. Colchicine: Colchicine itself is non-toxic, but after entering the human body, it is oxidized to dicolchicine oxide is toxic. Symptoms such as nausea, vomiting, abdominal pain, diarrhea, thirst, etc. may occur, and severe cases may have symptoms such as bloody stool, hematuria or anuria.
7. Pathogenic bacteria: Some vegetables may be easily contaminated by pathogenic bacteria because of their special growth environment, and the more common ones are Listeria, Salmonella and E. coli.
Among them, salmonella and E. coli mainly cause vomiting, abdominal pain, diarrhea, fever and other symptoms; Listeria can harm the health of immunocompromised people such as infants and the elderly. Listeria infection causes symptoms such as fever, headache, nausea, abdominal pain, and diarrhea. Miscarriages and even fetal death may occur after infection in pregnant women.
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These 7 types of vegetables are not blanched and may be harmful to health
1. Cowpeas, beans, red kidney beans and other legumes
These legumes and vegetables contain more plant lectins, and eating too much plant lectins may be poisoned, causing nausea, vomiting, abdominal pain, diarrhea, etc.
【Recommended Consumption Method】Plant lectin is not heat-tolerant, as long as it is thoroughly heated, it can destroy its structure. These legumes and vegetables are usually heated at 100°C for more than 10 minutes to be safe. If the heating is not thorough, the retention of toxins can easily lead to food poisoning.
cowpea
kidney bean
Red kidney beans
2. Yellow cauliflower
Fresh yellow cauliflower contains colchicine and cannot be eaten directly. Colchicine is water-soluble, and must be treated to remove colchicine before eating fresh yellow cauliflower.
【Recommended Consumption Method】If you want to eat fresh yellow cauliflower, remove the stamen of yellow cauliflower before eating, then blanch water, and then soak in cold water for more than 1 hour, which can reduce toxicity.
Yellow cauliflower
3. Toon
Although the nitrite content in most toons (especially fresh toon) is generally not high and will not be harmful, the nitrite in some toons sometimes reaches the order of thousands of milligrams per kilogram, and poisoning may occur if you accidentally eat more.
【Recommended Eating Method】Before eating toon, as long as you blanch it with hot water, you can remove most of the nitrite. Studies have shown that when blanching toon, about 80% of nitrite can be removed in 30 seconds, and 83.86% of nitrite can be removed in 45 seconds. Therefore, when eating toon, be sure to blanch it with boiling water for 30-60 seconds.
Chinese toon
4. Spinach, purslane, cocoon, bamboo shoots and other vegetables with a bitter taste
This type of vegetable has a high content of oxalic acid, and vegetables with high oxalic acid content usually taste more astringent and not very delicious. However, oxalic acid is soluble in water, so it is best to blanch these vegetables with water before eating to get rid of oxalic acid.
【Recommended eating method】Generally speaking, spinach, purslane and other leafy vegetables only need to be blanched for 15-20 seconds after boiling water, the color of the leaves will become darker, and you can scoop them up. Vegetables such as rhizomes such as cocoon white and bamboo shoots should be blanched for 3~5 minutes.
If you use these vegetables to cook soup, you can first blanch them separately and put them away, and finally wait for the soup to be almost cooked, and then add the vegetables to the soup, so that there will not be a lot of oxalic acid in the soup, and you can retain more vitamins.
spinach
Portulaca oleracea
Cocoon
bamboo shoots
5. Bean sprouts
Bean sprouts have a sweet and refreshing taste, and many families still make them at home, but bean sprouts are easily contaminated by microorganisms.
The World Health Organization's assessment of sprouts such as bean sprouts suggests that there may be a risk of contamination with pathogenic bacteria in sprouts. Because the environment in which bean sprouts grow - humid and warm places - is also suitable for microbial growth and reproduction, which makes the chance of bean sprouts being contaminated by pathogenic bacteria, the more common are Listeria, salmonella and E. coli.
【Recommended Consumption Method】These pathogenic bacteria are afraid of heat, and they can be killed by blanching with hot water to ensure the safety of eating. Therefore, eat bean sprouts, especially cold sprouts, be sure to blanch them in hot water before eating.
sprouts
6. Cassava, white fruit
Cassava and white fruit are foods containing more cyanogenic glycosides, which can be dissolved in water and can also be destroyed by heating.
【Recommended Eating Method】It is also edible after removing the seed coat and germ, soaking and then blanching it thoroughly, but do not eat more.
cassava
ginkgo
7. Cauliflower, fungus, kelp and other vegetables that are difficult to clean
Cauliflower, fungus, kelp, etc., because of the structure, may not be easy to clean, at this time can be blanched with water.
cauliflower
agaric
kelp
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When blanching, under cold water or hot water?
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Will the nutrients be lost when vegetables are blanched?
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Precautions for proper blanching
In 2023
China Women's Daily
Source/CCTV Life Circle Pictures/Photogram Network Editor/Pastoral Huang Butterfly Review/Yifan Producer/Zhifei