Which foods shouldn't be eaten too fresh?

The bottled water sold on the market, whether it's distilled water, reverse osmosis water, mineral water, or other purified water, is mostly disinfected with ozone as a final treatment before being bottled. Therefore, freshly filled bottled water will contain a relatively high concentration of ozone. Ozone is a toxic substance to humans, and if you drink it while it's fresh, you will undoubtedly ingest this toxin along with the water. If you let the bottled water sit for another 1 to 2 days, the ozone will naturally dissipate. At that point, drinking it will not pose a risk of poisoning. According to regulations, bottled water must pass inspection before it can leave the factory, and this process takes 48 hours. Therefore, drinking bottled water that has been inspected and released according to regulations is safe.

Fresh jellyfish contains a lot of water, has a thick body, and also contains toxins. Only after being salted with alum three times (commonly known as "three alum" processing) to dehydrate it three times can the toxins be completely removed with the water. After this process, the jellyfish will be light red or light yellow, have uniform thickness and a firm texture, and no water can be squeezed out even when pressed firmly. Only this kind of jellyfish is edible. When traveling to jellyfish-producing areas, you may encounter vendors selling jellyfish that has not been treated or has only been salted once or twice. You must absolutely not taste or buy it.

Also known as golden needles, unprocessed fresh daylilies contain colchicine. Colchicine itself is non-toxic, but after being eaten, it is converted in the body into a highly toxic substance called colchicine dioxide. According to experimental estimates, as little as 3 milligrams of colchicine is enough to cause nausea, vomiting, headaches, and abdominal pain. A larger dose can lead to blood in the urine or stool, and 20 milligrams can be fatal. Dried daylilies are steamed and processed, which dissolves the colchicine, making them non-toxic.

They contain a photosensitive substance called porphyrin. After consumption, if exposed to sunlight, it can cause skin itching and edema. In severe cases, it can lead to skin necrosis. If the edema occurs in the throat mucosa, it can cause difficulty breathing. Dried wood ear mushrooms are a product that has been sun-dried. During the sun-drying process, most of the porphyrin is decomposed. Furthermore, before being eaten, the dried mushrooms are soaked in water, which dissolves any remaining toxins, making the rehydrated dried wood ear mushrooms non-toxic.

Fresh vegetables all contain a certain amount of non-toxic nitrate. During the pickling process, it is reduced into toxic nitrite. Generally, nitrite levels begin to increase significantly 4 hours after pickling, peak between 14 to 20 days, and then gradually decrease. Therefore, you should either eat pickled vegetables within 4 hours or wait until they have been pickled for more than 30 days. Nitrite can cause cyanosis and other hypoxia symptoms, and it can also combine with secondary amines in food to form carcinogenic nitrosamines.