First, fresh pickles Fresh pickles contain a certain amount of non-toxic nitrate, which will be reduced to toxic nitrite during the pickling process. Under normal circumstances, nitrite increased obviously at 4 hours after curing, reached the peak at 14-20 days, and then gradually decreased. Therefore, either eat pickled pickles within 4 hours or eat pickled pickles for more than 30 days. Nitrite can cause anoxic symptoms such as cyanosis, and can also combine with secondary amines in food to form carcinogenic nitrosamines.

Second, fresh day lily is also called golden cabbage. Fresh products contain colchicine, which is non-toxic, but it will be oxidized into highly toxic colchicine in the body after eating. According to the experimental calculation, as long as you eat 3 mg of colchicine, it is enough to make people sick, vomit, have a headache and abdominal pain. Eating too much can cause hematuria or bloody stool, and 20 mg can cause death. After the dried day lily is cooked, colchicine will dissolve out, so it is non-toxic.

Recently, it was reported in a newspaper that farmers in a certain city now take cows to the street to sell them in a crowded way, which not only preserves the freshest milk for the citizens, but also prevents milk from being adulterated, so it is very popular with the citizens. In fact, this primitive way of selling milk can't guarantee the sanitation of milking, the cleaning and disinfection of containers, the health of milkmen and the cleaning and disinfection of hands, so it has long been eliminated. Besides, who knows if the cow selling milk now is sick? Therefore, this particularly fresh milk is absolutely not to be tasted.

Four. Barreled water The bottled water on the market, whether it is distilled water, mineral water, purified water or other purified water, is mostly disinfected with ozone before it is packed, so the bottled water just filled will contain high concentration of ozone. Ozone is a poison to people. If you drink fresh, you will undoubtedly take poison with you. If these bottled waters are left for another 1 to 2 days, the ozone will disappear naturally, so there is no need to drink poison.

5. Fresh jellyfish Fresh jellyfish contain more water, thick skin and contain toxins. Fresh jellyfish can only be cured with salt and alum (commonly known as alum) for three times before the toxin can be discharged with water. The three alum jellyfish is reddish or yellowish, with uniform thickness and toughness, and it can't squeeze water even if it is squeezed hard. This jellyfish can only be eaten.

6. Fresh auricularia contains a porphyrin photosensitive substance. If you are exposed to the sun after eating, it will cause itching and edema of the skin, and in serious cases it will cause skin necrosis. If there is edema in the throat mucosa, it will lead to dyspnea. The dried auricularia auricula is the finished product after exposure. In the process of exposure, most porphyrin will decompose. Soak dried auricularia auricula in water before eating, and the residual toxin contained in it will dissolve in water, making dried auricularia auricula non-toxic.