A lot of food, as long as it is "overnight", becomes unforgiving.
Overnight water, overnight tea, overnight dishes, overnight watermelon...
This one by one, sigh! Rumors are highly toxic!
Can't they really eat them?! This one-time article makes it clear!
Rumor: Too high nitrite in overnight water can cause cancer.
Truth: Overnight water can be drunk.
Overnight water does contain nitrites, but talking about toxicity without dose is tantamount to playing hooliganism.
In the mainland drinking water sanitation standard, the nitrite content is specified as ≤1 mg/L [1]. The study found that after 3 days of bottled water, purified water, and tap water (many times overnight), nitrite was still within the safe range [2] and could be safely drunk.
Overnight water should really pay attention to: to cover the lid, if not cover the lid and still put it on the old drink, the water may be contaminated, falling into dust, flying insects, and may also exceed the standard of bacteria.
Rumor: Overnight tea is as poisonous as a snake, and drinking it also causes cancer.
Truth: Overnight tea can be drunk.
According to the Beijing Nutrient Source Experimental Test [4], whether it is Pu'er tea or chrysanthemum tea, the nitrite content does not change much after 12 hours and 24 hours, it is less than 0.2 mg/L (in line with the safety limit standard<1 mg/L), and Longjing is slightly higher but not more than 0.3 mg/L, which will not cause cancer.
(Source: soogif)
As for why the overnight tea changes color, this is the oxidation of the tea polyphenols inside, coupled with the increase in tannic acid after a long time, the taste is worse, but it will not endanger health.
Some people are worried about the increase in bacteria in overnight tea, drinking diarrhea. In fact, as long as the tea itself does not have pathogenic bacteria such as Salmonella and Staphylococcus aureus, bacterial food poisoning is unlikely to occur.
Rumor: overnight dishes can not be eaten, eat more will cause cancer.
Truth: You can eat, remember "put the refrigerator in time, leftover meat is not leftover, cold dishes do not stay."
Zhejiang Ningbo Food Inspection Institute specially verified in 2019 that they made 30 home-cooked dishes and stored them at 4 °C and 25 °C for 0, 6, 12, and 24 hours respectively [5].
Experiments have shown that the nitrite content of various dishes stored at 4 °C after 24 hours and when it is just out of the pot has not changed much, less than 1/3 of the limit value of nitrite specified by the state [6], and will not cause cancer.
At 25 ° C, the meat dish is fine overnight, but the nitrite of the leafy vegetable will increase significantly, and it is best to eat it within 6 hours.
Also note: the second meal of the overnight dish must be fully heated (heated at 100 ° C for more than 3 minutes), it is best to add some green onions, ginger and garlic, seasoning and sterilization.
Rumor: Overnight watermelon can not be eaten, wrapped plastic wrap bacteria multiply faster.
Truth: Overnight watermelon can be eaten, wrapped plastic wrap refrigeration is no problem.
Most of the watermelon harm incidents that have occurred in the news are caused by the knife that cuts watermelons and the preservation environment is not clean enough, and pathogenic bacteria are multiplied in watermelons.
Researchers at the Fujian Academy of Agricultural Sciences have done experiments specifically, they selected three varieties of watermelon, cut open and covered with plastic wrap, put in the refrigerator (4 ° C) for 16 hours [7], the results found that the total number of colonies of overnight watermelon and fresh watermelon is similar, which is safe to eat.
In order to ensure safety, before cutting watermelon, you must clean the knife, watermelon, hand, and board. Before refrigerating, cover with breathable plastic wrap.
Rumor: Overnight foam fungus is poisonous.
Truth: It really can't be eaten.
Bubble fungus, white fungus to avoid overnight!
Foam fungus, white fungus and fermented rice noodles and starch products are easily contaminated by Pseudomonas cocos, which produces high-temperature resistant rice yeast acid toxins at room temperature. People who eat it will not only have abdominal pain, bloating, diarrhea, nausea and vomiting, but also excessive intake can lead to multi-organ failure and even death in the human body!
It was initially identified as the culprit of the Heilongjiang sour soup poisoning incident (which led to the death of 9 people).
Soak your own fungus, white fungus, generally cold water soaked for 1 to 2 hours can be processed and eaten, it is too late to do not exceed 4 hours, with hot water to soak the time is shorter, if the mucus, the surface is sticky, smelly, it is best to throw it away.
I really can't ask for this! Long anger hurts!
Finally, I send you four sentences of "Mo Qi":
Others are angry with me,
There is no one to replace the disease.
If I am angry with anyone who wishes,
Moreover, it hurts and is laborious.
Special Author: Huang Yuanyuan | Registered Dietitian
Review expert: Zuo Xiaoxia | Director of the Nutrition Department of the Eighth Medical Center of the PLA General Hospital
bibliography
[1] GB5749-2006, Sanitary Standard for Drinking Water.
Chen Ying,Xiao Yanjie,Liu Xiaolin. Changes in nitrite and nitrate content at different times after drinking water is boiled[J]. Journal of Jinzhou Medical University, 2018, Vol. 39, No. 6.
Qin Pinzhang. Several Opinions on Modifying the Sanitary Standards for the Use of Nitrates and Nitrites for Food Additives[J], Chinese Journal of Preventive Medicine, 2005, 6: 150-151.
[4] Overnight tea is as poisonous as a snake? CCTV Experiments Are Still Innocent[J], China Tea, 2014, 36(06): 23.
[5]http://py.zjol.com.cn/rdgz/201907/t20190724_10651911.shtml
Zhejiang Online "Overnight Vegetables Are Toxic? Ningbo Food Inspection Institute uses 450 data to tell you the answer".
[6] GB 2762-2005, Limits of contaminants in food.
Lü Xin,Chen Lihua,Li Xiaolin,Liu Lanying,Huang Wei,Li Yueren. Evaluation of edible safety of fresh-cut watermelon after overnight refrigeration[J].Fujian Journal of Agricultural Sciences,2018,33(08):865-869.
*The content of this article is a popularization of health knowledge and cannot be used as a specific diagnosis and treatment recommendation, nor is it a substitute for face-to-face consultation by a practicing physician, for reference only.
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