Everyone knows that food should be eaten fresh; otherwise, its color, aroma, and flavor will deteriorate. In severe cases, it can spoil and lose its edibility, or even cause food poisoning. However, everything has two sides. Some foods, if eaten too fresh, can be detrimental to health or even cause illness. Examples are as follows: Milk
Recently, some newspapers have reported that farmers in a certain city lead their cows to the street to milk and sell on the spot, allowing citizens to drink the freshest milk, save money, and prevent adulteration. This has become quite popular. In fact, this is a foolish regression to primitive times. With this most原始的销售方式, the hygiene of the milking environment, the cleanliness and disinfection of containers, the health of the milker, and the disinfection of their hands cannot be guaranteed, which is why it has long been eliminated. Moreover, who knows if the cows being milked on the spot are sick? If a cow is infected with pathogenic microorganisms such as Brucella, tuberculosis bacillus, Staphylococcus aureus, or foot-and-mouth disease virus, those who drink the "fresh" milk will undoubtedly be infected or fall ill. The resulting health damage is imaginable, and the additional financial burden could be thousands of times the price of the fresh milk or more. Therefore, one must absolutely not try this "fresh" milk. Formal dairy farms have certain requirements for the health of the cows and the hygiene of the milking process, and the milk must be pasteurized before leaving the factory. If the raw material is contaminated by any microorganisms, it can be effectively disinfected. Of course, pasteurized milk must be refrigerated and consumed as soon as possible. Bottled Water
Commercially available bottled water, whether distilled, reverse osmosis, mineral, or other purified water, is mostly treated with ozone as a final disinfection before being bottled. Therefore, newly filled bottled water will contain a relatively high concentration of ozone. Ozone is a toxic substance to humans. If you drink it "fresh," you will undoubtedly ingest this toxin along with the water. If the bottled water is left for another 1-2 days, the ozone will naturally dissipate, and then there is no risk of "drinking poison." According to regulations, produced bottled water must pass inspection before it can be released for sale, a process that takes 48 hours. Therefore, drinking bottled water that has been inspected and released according to regulations is the safest option. Fresh Jellyfish
Fresh jellyfish contains a lot of water, has a thicker body, and also contains toxins. It must be salted and alum-pickled three times (commonly known as "three-alum") to dehydrate the fresh jellyfish three times, allowing the toxins to be completely expelled with the water. "Three-alum" jellyfish is light red or light yellow, has uniform thickness and is resilient, and no water can be squeezed out even with force. Only this kind of jellyfish is edible. When traveling to jellyfish-producing areas, you may encounter vendors selling untreated jellyfish or jellyfish that has only been pickled once or twice. You must absolutely not taste or buy it. Fresh Daylilies
Also known as golden needles, unprocessed fresh daylilies contain colchicine. Colchicine itself is non-toxic, but after being eaten, it is oxidized in the body into highly toxic colchicine dioxide. According to experimental calculations, just 3 milligrams of colchicine is enough to cause nausea, vomiting, headache, and abdominal pain. A larger dose can lead to hematuria or bloody stools, and 20 milligrams can be fatal. Dried daylilies are steamed and processed, during which the colchicine is dissolved, making them non-toxic. Fresh Wood Ear Mushrooms
Fresh wood ear mushrooms contain a porphyrin photosensitive substance. After consumption, exposure to sunlight can cause skin itching and edema. In severe cases, it can lead to skin necrosis. If edema occurs in the pharyngeal mucosa, it can cause difficulty in breathing. Dried wood ear mushrooms are finished products that have been sun-dried. During the sun-drying process, most of the porphyrin is decomposed. Before consumption, dried wood ear mushrooms are soaked in water, and any remaining toxins are dissolved into the water, making the rehydrated dried wood ear mushrooms non-toxic. Fresh Pickles
Fresh vegetables all contain a certain amount of non-toxic nitrates. During the salting process, they are reduced into toxic nitrites. Generally, nitrites begin to increase significantly 4 hours after salting, peak at 14-20 days, and then gradually decrease. Therefore, either eat the heavily pickled vegetables within 4 hours, or it is better to eat those pickled for more than 30 days. Nitrites can cause cyanosis and other hypoxia symptoms, and can also combine with secondary amines in food to form carcinogenic nitrosamines.