So what is industrial salt? What's the harm? The purpose of industrial salt is for industrial production, and the harm to human body after eating is unimaginable. The content of heavy metals in industrial salt exceeds the standard, and it contains toxic and harmful substances such as barium, lead and nitrite. Long-term intake will lead to mental retardation, slow growth and dementia in infants. Adult consumption will affect growth and development, leading to chronic or acute poisoning, carcinogenesis, and serious death. It may also enter the fetus through the placenta, causing fetal malformation.
Now remind you, pay attention to distinguish the authenticity of edible salt. You can distinguish the authenticity of small package salt by the following methods.
First look at the packaging. Iodized salt that meets the national standards must be packaged in small packages, and the printed patterns and characters on the packaging bags are very clear. The packaging material is double-layer composite film or other higher-end packaging materials. The mechanical packaging is sealed and the sealing strip has the production date. Among them, the product packaging of Zhongyan Company has a watermark, and the words Zhongyan can be seen under the light, while the printing of fake and shoddy salt packaging bags is very rough and fuzzy, and some even use manual packaging, and the sealing strip is simple.
Second, look at the anti-counterfeiting logo. The anti-counterfeiting mark of iodized salt in small package that meets the national standard is sandwiched between double-layer composite films and cannot be uncovered, so it is properly placed. The anti-counterfeiting signs of fake and shoddy salt are generally pasted after packaging, which can be uncovered by hand, and the pasting is obviously irregular.
Three, the implementation standard of industrial salt is GB/T5462, and the implementation standard of edible salt is GB/T546 1.
Fourth, the packaging of industrial salt is generally 50 kilograms in a woven bag, and the price per kilogram is cheap. Edible salt is generally packed in small bags, each bag is 400-500g, and the packaging bag is marked with anti-counterfeiting, product standards, code spraying and other signs.
Fifth, industrial salt is coarse in texture and contains toxic impurities such as nitrite, while edible salt is fine in texture and can be identified.
Extension: Introduction to Salt
Salt refers to sea salt, well salt, mineral salt, lake salt and soil salt from different sources. Their main component is sodium chloride, and the state stipulates that the sodium chloride content of well salt and mineral salt shall not be less than 95%. Salt contains barium salt, chloride, magnesium, lead, arsenic, zinc, sulfate and other impurities. We stipulate that the content of barium should not exceed 20 mg/kg. Too much magnesium and calcium in salt will make the salt bitter, and too high fluorine content will also cause poisoning. In recent years, many experiments have confirmed that there is a certain relationship between salt intake and the incidence of hypertension. Excessive salt intake in the diet can cause high blood pressure. The World Health Organization (WHO) suggests that taking less than 6 grams of salt per person per day can prevent coronary heart disease and hypertension. In China, adults are required to consume 6 grams of salt every day to meet the body's need for sodium.
origin
Salt originated in China. The word "salt" originally meant "salt water boiled in a container". It is recorded in Shuowen that raw food is called brine and cooked food is called salt. Legend has it that there was a warlord named Su Sha in the era of the Yellow Emperor who boiled brine with seawater and fried it into blue, yellow, white, black and purple salt. Around the time of Shennong (Emperor Yan) and Huangdi, people in China began to make salt. In ancient China, salt was boiled in sea water. In 1950s, cultural relics unearthed in Fujian, including salt frying utensils, proved that the ancients had learned to cook sea salt in Yangshao period (5000-3000 BC). According to the above information and physical evidence, in China, the origin of salt was as far back as 5,000 years ago in the Yanhuang period. Su Sha, the inventor, was the originator of making salt from seawater and roasting by fire. Later generations respectfully called him "Salt Sect". Before the Song Dynasty, a temple dedicated to Yanzong was built ten miles southeast of Anyi County, Xiezhou, Hedong. During the Tongzhi period of Qing Dynasty, Qiao Songnian, the messenger of salt transportation, built a "salt temple" in Taizhou. The owner was a person who cooked the sea to get salt. Su Sha, a plastic bottle for transporting brine in the Shang and Zhou Dynasties, and Guan Zhong, who practiced the "salt administration official camp" in Qi in the Spring and Autumn Period, were placed in the position of accompanying sacrifices.
China is also the birthplace of salt wells. Biography of King Shu: "During the Xuan Di Festival (69 BC-66 BC), dozens of salt wells were drilled." Since the Han Dynasty, salt ponds have also been used to extract salt. Wang Xun's Luo Du Fu: "There is a salt pond in the east, which is clean and fresh, natural and not hard to cook." Serina Liu's "Lu Du Fu": "There are salt ponds, which are fried in Yangchun and sprayed with fire. Salt self-sufficiency, no loss, no diligence. "
In the early days, salt was directly put on the stove rack and cooked in an iron pan. This primitive salt cooking is time-consuming and laborious, with low yield and high salt price. Thus, from the birth of salt, the royal family formulated the salt law. In the Zhou Dynasty, officials in charge of salt administration were called "salt people". Li Zhoutian's Yan Guanren describes being in charge of salt administration and managing all kinds of salt affairs. Bitter salt and scattered salt should be used for sacrifice, special-shaped salt should be used for hospitality, and salt should be used for royal meals. Emperor Wu of the Han Dynasty enacted a salt law, monopolized official salt and prohibited private property. According to historical records, anyone who dared to make salt privately at that time would be punished by cutting off his left toe. In the Jin Dynasty, people who cooked salt privately were sentenced to four years' imprisonment, and officials were sentenced to two years' imprisonment. After the establishment of the Salt Law, there are regulations for citizens to eat salt. "Pipe": "In January, the amount of salt is less than five liters for husband, three liters for wife and two liters for baby."
kind
There were many kinds of salt in ancient times, including crimson snow, peach blossom, blue, purple and white. From the source, it can be divided into: sea salt is fried by sea brine, well salt is fried by well brine, alkali salt is fried by scraping alkaline earth, pool salt is dried by pool brine, and cliff salt is born between soil cliffs. Sea salt, well salt and alkali salt come from people, while pool salt and cliff salt come from heaven. "Ming History" records: "Xiezhou salt is made of geomantic omen, Ningxia salt scraped the ground, Huai and Zhejiang salt boiled, Sichuan and Yunnan salt pumped wells, Fujian and Guangdong salt bittern, Huainan salt fried, Huaibei salt dried, Shandong salt fried and dried, with a large scale." Tao Hongjing's Records of Famous Doctors in the Southern Dynasties recorded that East Sea Salt, North Sea Salt, South China Sea Salt, Hedong Salt Pool, Liang Yi Salt Well, Xiqiangshan Salt and Huzhongshu Salt have different colors, and Hedong Salt wins.
use
Salt has a wide range of functions: sterilization, tooth protection, beauty, skin cleaning, decontamination, medical treatment, important chemical raw materials, edible chemical properties;
1. It can react with silver nitrate to generate silver chloride precipitate;
2. The solid salt can be heated with concentrated sulfuric acid to obtain hydrogen chloride gas;
3. Chlorine, hydrogen and sodium hydroxide can be obtained by electrolysis of sodium chloride solution;
4. Sodium and chlorine can be obtained by electrolytic melting of sodium chloride.
Matters needing attention
First, buy less and eat in time.
Buy a small amount, and then buy it after eating to prevent iodine from sublimating. Because potassium iodate will decompose and volatilize under the conditions of heat, light, wind and humidity.
Second, avoid high temperature.
Avoid putting iodized salt at high temperature when cooking soup. The edible rate of iodized salt in cooking and frying is only 10%, and the intermediate edible rate is 60%. The edible rate of iodized salt during cooking is 90%; The edible rate of cold iodized salt can reach 100%.
Third, avoid prolonged exposure to containers.
Iodized salt is easy to volatilize if it is exposed to sunlight and air for a long time. It is best to put it in a colored glass bottle and seal it tightly with the back cover.
Fourth, avoid adding vinegar
The combination of iodine with acidic substance will be destroyed. According to the test, if vinegar is added during cooking, the consumption rate of iodine will decrease by 40% ~ 60%. In addition, when iodized salt meets acidic vegetables (such as sauerkraut), the consumption rate will also drop.
Verb (abbreviation for verb) salt and radiation
On March 20 1 1 year, there was a phenomenon of snapping up salt in supermarkets across the country. It is understood that there are two main reasons for citizens to snap up salt. First, the salt in our country is iodized salt, and iodine is the main component of iodine tablets, potassium iodide. Many citizens may think that eating more salt can prevent radiation at a critical moment. The other is the residents of some coastal cities in Guangdong, who are worried that nuclear radiation pollution in Japan will make seawater unusable, and once the supply of salt is in short supply, the price will rise.
Regarding the first concern, experts from the Guangdong Provincial Center for Disease Control and Prevention said that the iodine content in salt is very low, and even if people eat a lot of salt, it will not have much radiation protection effect. Excessive consumption of iodized salt is harmful to human health, which is said by the head of the health department.
Regarding the second concern, the relevant person in charge of the Salt Industry Corporation said that the relevant state departments have responded, saying that Japanese nuclear radiation has not had any impact on China. "This impact is all-round, including the sea. In addition to sea salt, Guangdong also supplies mineral salt to the market. " The person in charge said that the mineral salt was extracted from 3 meters underground without any pollution. The public need not panic about the quality of salt.