China is a veritable "chopsticks country". Recently, a news that "chopsticks have been used for more than three months or may induce liver cancer" spread widely on the Internet and immediately attracted public attention. The reporter of the Yangtze Evening News found that a pair of chopsticks has been used for several years in many citizens' homes. However, experts found through experiments that the bacterial content of wooden chopsticks is exaggerated after long use, so it is recommended to always replace them with good ones.
How long have you used your chopsticks This is very clear!
Chopsticks change color quickly
After using chopsticks for a long time, their color will become darker or lighter with time and frequency of use. It is recommended to replace chopsticks at this time. The color of chopsticks changes, indicating that the nature of the material itself must change. The long-term accumulation of bacteria is the main factor of color change. When using chopsticks, we should observe every day whether there are spots, especially mold spots, on the surface of chopsticks. If there are spots on the chopsticks that are not of the natural color of bamboo or wood, it means that the chopsticks are likely to have become mouldy and deteriorated and cannot be used any more.
Four Questions about Chopsticks
1 Can it cause cancer if used for more than three months?
A kind of carcinogen "aflatoxin" may grow after a long time of use
Chopsticks can cause cancer? The reporter found that the source of the microblog came from an investigation report of CCTV. CCTV reported on August 1 that ordinary chopsticks will become darker or lighter with the frequency of use when they are used for 3-6 months. Overused disposable chopsticks will breed various molds, which may lead to infection diarrhea , vomiting and other diseases. Severe mildewed chopsticks will breed "aflatoxin". The reporter of the Yangtze Evening News learned that the substance is classified as a carcinogen by the World Health Organization, which will damage human and animal liver tissue and has been widely recognized as inducing liver cancer.
The reporter learned that in order to prolong the service life, the surface of wooden chopsticks sold on the market has been painted with a layer of edible paint - raw paint, so that the surface of chopsticks is not easy to be attached by bacteria. However, after the wooden chopsticks are used for a long time, the surface lacquer is easy to fall off or be damaged, and the wood chips become loose, which provides a living space for bacteria to breed. At the same time, household chopsticks are washed with water for a long time and placed in the cabinet, which results in high water content of chopsticks and provides a very good growth environment for bacteria reproduction.
Although Aspergillus flavus mostly exists in moldy grains, Du, Chief of the Microbial Inspection and Quarantine Section of Nanjing Center for Disease Control and Prevention, believes that "it is possible to breed Aspergillus flavus on chopsticks." In a humid and sunless environment, fungi are easy to grow, and Aspergillus flavus is no exception.
Can't the carcinogen be washed away?
It is recommended to put chopsticks into boiling water for half an hour every week and then dry them
"I never knew it before". After the theory that chopsticks cause cancer became popular on the Internet, many netizens found it hard to believe, and even felt "unreliable". Yesterday, the reporter consulted 20 people around him, and only two of them proposed that they would change the chopsticks used at home once every six months or so.
Dampness will cause mildew. Will thorough drying improve the situation? The reporter consulted Zhejiang Tianzhu, the manufacturer of chopsticks for many years. Miss Liu of the company told the reporter that the production of chopsticks "cannot be too dry or too wet, there is a certain moisture standard." If it is too dry, it will cause the bamboo and wood chopsticks to be distorted. For ordinary people, the most common method is to wash the chopsticks and put them into the chopsticks box to drain naturally, but water will inevitably accumulate. At the same time, the reporter also learned that aflatoxin is heat-resistant, and it is difficult to achieve complete sterilization at the cooking temperature in daily life.
However, Du Section Chief of Nanjing CDC suggested that chopsticks should be boiled in boiling water for half an hour every week, and then put in the air to dry before use, which can still achieve a good disinfection effect.
3. Chopsticks also have a shelf life?
Experiments show that it is appropriate to replace chopsticks every six months
The reporter visited the Wal Mart supermarket located in Xinjiekou, Nanjing, and found that more than half of the chopsticks are made of bamboo or wood, with a small number of stainless steel or alloy chopsticks. Among the eight brands of chopsticks sold, four brands of chopsticks are marked with the words "It is better to use them for 3-6 months" or "Please replace them in time" on some hardbound products. As for the "shelf life" of chopsticks, Miss Liu of Zhejiang Tianzhu Company believes that this statement is "also inaccurate". Not that chopsticks will deteriorate immediately after the "shelf life", but that "long-term use of chopsticks will cause deformation and blackening". However, there is no accurate data standard for this half year or three to five month period.
Dong Jinshi, secretary-general of the International Food Packaging Association, said that he had obtained through experimental comparison that under the same conditions, the longer the chopsticks were used, the more bacteria were detected on their cross sections; Half yearly replacement is the "appropriate" time node. However, through inquiry, the reporter did not obtain any other accurate basis or measurement standard for the replacement time of chopsticks.
Prior to that, the state has issued mandatory standards on disposable bamboo chopsticks and wooden chopsticks, which clearly stipulate the product type, inspection rules, packaging, marking, storage and transportation of disposable chopsticks. But until today, there is still no unified national standard for reusable chopsticks commonly used in families. Dong Jinshi introduced that the International Food Packaging Association had proposed to draft the Hygienic Standard for Reusable Chopsticks in 2010, but this standard has not been accurately responded to at present.
4 How to choose chopsticks?
The best choice for household chopsticks is bamboo chopsticks or wooden chopsticks coated with lacquer
In addition to ordinary bamboo chopsticks, there are more and more kinds of wooden chopsticks on the market. In the supermarket, the reporter saw chopsticks made of different wood, such as sandalwood, incense wood, clematis, kale bean wood, as well as metal chopsticks, melamine chopsticks, etc. The reporter learned from Zhejiang Tianzhu that wooden chopsticks still occupy most of the market, with more bamboo chopsticks.
Dong Jinshi, secretary-general of the International Food Packaging Association, believes that bamboo chopsticks or wooden chopsticks coated with lacquer are the best choice for family chopsticks. At present, many units use chopsticks similar to plastic materials in their canteens. Dong Jinshi introduced that this is a melamine material. If it is cleaned, there is less chance of bacteria breeding. However, we should pay attention to the QS quality mark and guard against fake and inferior products. At the same time, these chopsticks are not suitable for high temperature conditions to prevent the secretion of harmful substances. Intern Zhou Jing, reporter Zhang Jun
