Nitrite in overnight food is fatal

Nowadays, almost every household has a refrigerator. Especially during festivals, there will be leftovers. The uneaten dishes are all put into the refrigerator. But have you realized the safety issues of overnight dishes? Overnight dishes will produce nitrite, which is often fatal.

1. Leftover vegetables produce deadly nitrites

Some overnight vegetables, especially overnight green leafy vegetables, not only have low nutritional value, but also produce pathogenic nitrites. The amount of nitrite produced in stored vegetables increases with the extension of storage time and the increase of temperature. However, if the vegetables are refrigerated in the refrigerator (2-6 degrees Celsius), the increase of nitrite will be less.

Some high-protein and high-fat leftovers are even more inedible. Harmful bacteria in the air will attach to leftovers and begin to multiply within 2 hours. As we all know, most proteins and fats will produce harmful substances under the action of bacteria, such as hydrogen sulfide, amines, phenols, etc. These substances are harmful to the human body.

If it is winter, some families think that the weather is cold and leftovers do not need to be refrigerated. This view is also wrong. Nowadays, the widespread use of refrigerators in cities has reduced the amount of nitrite people ingest from food, but this does not mean that you can put vegetables in the refrigerator without any worries; over time, the nitrite content will still increase.

2. Nitrite in meat is higher than in vegetables

In order to give everyone a more objective understanding of the changes in nitrite content in leftovers, the experimenters specially divided the four dishes into four portions, put them into disposable biodegradable lunch boxes, wrapped them in plastic wrap, and attached labels for half an hour, 6 hours, 18 hours, and 24 hours respectively. The samples were then placed in a laboratory refrigerator and refrigerated at 4°C, which is also the temperature set for ordinary household refrigerators.

The experimenters first ground the food into a slurry, weighed 1g (note: g) of the sample into a conical flask, and diluted it with distilled water. Let it stand in the dark for 15 minutes and read the nitrite content directly using a rapid detector. To ensure the accuracy of the test results, each sample was tested 3 times and the average value was taken.

Half an hour after being taken out of the pot, the test results of the three dishes, stir-fried vegetables, scrambled eggs with leeks, and braised pork, showed that the nitrite content did not exceed the maximum limit of my country's "Standards for Limits of Contaminants in Food", that is, 4 mg/kg for vegetables and 3 mg/kg for meat (Note: mg milligrams, kg kilograms). However, the nitrite content in braised pork is higher than that in scrambled eggs with leeks and stir-fried vegetables. In response to this, the experimenters said that meat dishes generally have more seasonings than vegetable dishes, and the seasonings themselves contain nitrates. These nitrates are converted into nitrites by microorganisms, which leads to a higher nitrite content in braised pork.