What is the use of sulfur dioxide?

As for sulfur dioxide, the National Standard for the Use of Food Additives for Food Safety (GB 2760-2014) clearly stipulates that it can be used as an "antioxidant, bleach, and preservative". In other words, sulfur dioxide is a legal food additive, not an illegal additive.

As a food additive, what is the use of sulfur dioxide? Yun Xinxin, a senior member of the American Food Technology Association and a popular science writer, said in the article that sulfur dioxide, a food additive, has a variety of functions, the most important is reducibility. Through the action of sulfur dioxide, some pigments can be bleached, and the oxidation of polyphenols can be inhibited to avoid Browning. For example, wine, without antioxidants, the color will gradually become darker, and bamboo shoots, mushrooms, etc., do not carry out "color protection" will soon turn black.

It is understood that in the process of natural fermentation of wine or fruit wine, yeast will produce a certain amount of sulfur dioxide, but the amount is small, can not achieve anti-corrosion, preservation, antioxidant effects, so it is necessary to add some additional sulfur dioxide or salt.

What foods contain sulfur dioxide?

Sulfur dioxide is widespread around the world, and foods containing sulfur dioxide are more common than many people think. In addition to sulfur dioxide itself, food production uses more of various compounds that can produce sulfur dioxide, such as potassium metabisulfite, sodium metabisulfite, sodium sulfite, sodium bisulfite, and sodium hyposulfite.

Yun Xinxin said there are 25 types of food in the national standard that can use these additives to produce sulfur dioxide, such as dried vegetables and fruits, nuts, flour, vegetable juice, fruit juice, fruit wine and so on. Some food fumigation with sulfur is also the effect of sulfur dioxide generated by the process, such as dried fruits, candied cold fruits, dried vegetables, fresh mushrooms and so on. Some sulfur dioxide sticks to the food during fumigation. In addition, some plants will produce a certain amount of sulfur dioxide during the growth and metabolism process.

Take wine as an example, in the development process of wine brewing, no additive has been found to be able to complete the preservation, anti-corrosion and anti-oxidation effects as sulfur dioxide. Therefore, sulfur dioxide can often be seen in the composition list on the wine bottle, but this does not mean that it is toxic and harmful.

Can't talk about toxicity without dose !

Why does the State allow the use of sulphur dioxide? Because after strict toxicological tests, in the limited content range, there is no need to worry about its poisoning and health hazards.

After sulfur dioxide enters the body, sulfite is generated, and it is oxidized to sulfate by sulfite oxidase in tissue cells, and finally excreted by urine after normal detoxification, so a small amount of sulfur dioxide enters the body can be considered safe and harmless.

The International Joint Expert Committee on Food Additives (JECFA) has set a relatively strict intake standard for sulfur dioxide - 0.7 mg per kilogram of body weight per day, if the weight is 60 kg of adults, the daily intake should not exceed 42 mg. In other words, as long as sulfur dioxide intake does not exceed the limit, it will not harm health.

A few days ago, the Beijing Municipal Bureau of Market Supervision released sampling information showing that the small and fragrant creamy watermelon seed (240g/bag, 2019/4/8) produced by Qiaqiaa Food Co., Ltd. was detected with a residual amount of sulfur dioxide of 0.022g/kg. According to this calculation, an adult weighing 60 kilograms has to eat close to 4 pounds of melon seeds a day to cause harm to the body.

For sulfur dioxide, although we should be vigilant, but do not panic and "biased", "put aside the dose to talk about toxicity, are playing rogue", can not smell the "additive" color change, see "exceeded" panic, but also need to distinguish between.