For consumers themselves, they should learn how to identify 'toxic foods' that contain inedible substances or excessive food additives, and protect themselves. Therefore, in daily life, you need to be vigilant when purchasing these foods.
Dried Chili Peppers
Caution: Sulfur-fumigated, the color should not be too bright.
Identification Method: Sulfur-fumigated dried chili peppers are bright and beautiful without spots. Normal dried chili peppers are a bit dark. Touch them with your hand; if your hand turns yellow, it has been processed with sulfur. Smell it carefully; sulfur-processed ones often have a sulfur smell.
Kelp
Caution: Chemically processed, especially bright green ones should not be bought.
Identification Method: Kelp that is plump, has an especially bright green color, and is very shiny is likely to have been chemically processed. The normal color of kelp is brownish-green or dark brownish-green. Normally, fresh kelp is usually scalded in boiling water and then dried, resulting in a grayish-green color.
Mushrooms
Caution: Soaked in bleach, snow-white and transparent to look at, but not good to eat.
Identification Method: Some mushrooms are snow-white and transparent, with no soil on them, and are also cheap. They are likely soaked in bleach—good to look at, but not to eat. Good mushrooms grow in grass ash and inevitably get some ash on them. Moreover, normal mushrooms feel a bit sticky to the touch, while bleached mushrooms feel smooth and not greasy.
Water-Soaked Foods
Caution: Soaked in formaldehyde, they crumble with a squeeze.
Identification Method: Common examples include water-soaked tendons, water-soaked sea cucumbers, and water-soaked sour fish. Unscrupulous people often use formaldehyde or hydrogen peroxide to process water-soaked foods. It is strictly prohibited in our country to use formaldehyde as a food preservative. To identify them, first, look: if the food is very white and unnaturally plump, avoid buying and eating it. Second, smell: foods soaked in formaldehyde may leave a pungent, strange odor. Third, touch: foods soaked in formaldehyde will crumble easily with a squeeze.
Dried Shrimp
Caution: Treated with ammonia, choose those that are dry and not sticky.
Identification Method: Some merchants treat damp dried shrimp with ammonia to make their surface appear the same as normal dried shrimp. Therefore, when choosing dried shrimp, be sure to select those that are dry, not sticky, have a fresh fragrance, and smell carefully for any pungent odors.
Watermelon
Caution: Hormone-ripened, with white seeds.
Identification Method: Watermelons treated with hormones have uneven yellow-green stripes on the rind. When cut open, the flesh is especially vibrant, but the seeds are white and it lacks sweetness. Such melons are prone to being misshapen, such as asymmetrical ends, a depressed middle, or enlarged ends, with color spots or large color differences on the surface. When eating watermelon, if the taste is not good, especially if there is a numbing sensation on the tongue, stop eating it immediately.
Goji Berries (Wolfberries)
Caution: Sulfur-fumigated, be wary if they have a sour or bitter taste.
Identification Method: Those that are especially bright red and shiny may be "toxic goji berries," while natural goji berries are slightly darker and have a bit of a earthy color. "Toxic goji berries" feel sticky to the touch, whereas natural ones are relatively dry. Additionally, natural goji berries are sour with a hint of sweetness, while "toxic goji berries" have a strong sour and bitter taste.
Bean Sprouts
Caution: Soaked in chemical fertilizers, do not choose those that are too thick and sturdy.
Identification Method: Naturally grown bean sprouts are straight-fibered, have firm roots, are shiny, white, and tender, slightly slender, with no rotten roots or tips. Bean sprouts soaked in chemical fertilizers have a grayish-white color, thick stalks, short roots, or no roots, and the beans have a bluish tint. If you break a sprout, water will seep out from the break, and some may still have a chemical fertilizer smell.
Rice
Caution: Polished with industrial paraffin wax and mineral oil, extremely shiny may be toxic.
Identification Method: When the rice you buy is extremely shiny, it is likely that the rice has been polished with mineral oil. When a small amount of this rice is soaked in hot water, it feels greasy when rubbed between the fingers; in severe cases, an oil film may float on the water. Also, look closely; because the oil-polished rice is often uneven in color, careful observation may reveal a slight light yellow tint on the grains.
Silver Ear Fungus (Tremella)
Caution: Sulfur-fumigated, whiter is not necessarily better.
Identification Method: The color of silver ear fungus is not an indicator that the whiter it is, the better quality it is. Silver ear fungus fumigated with sulfur can have its yellow color removed, appearing plump, full, and especially white. However, after a short storage time of about 10-20 days, it will oxidize and revert to its original yellow color and then turn red due to contact with air. When selecting silver ear fungus, take a small amount to taste; if the tongue feels a stinging or spicy sensation, it may have been fumigated with sulfur.
Black Fungus (Wood Ear Mushroom)
Caution: Soaked in alum and alkaline water, a strange smell may indicate adulteration.
Identification Method: After a bit of chewing, real black fungus has a pure taste without any strange odor and has a fresh fragrance. Fake fungus usually has the smell of the adulterant. For example, a bitter taste indicates it was soaked in alum water; a salty taste means it was soaked in salt water; a sweet taste means it was mixed with sugar water; and an alkaline taste means it was soaked in alkaline water.
Tripe (Honeycomb Tripe)
Caution: Soaked in hydrogen peroxide and formaldehyde, do not eat if it is very white and large.
Identification Method: Especially white tripe is soaked in hydrogen peroxide and formaldehyde for three to four days to become white. When buying, if the tripe is very white and unnaturally plump, avoid purchasing it. Tripe soaked in formaldehyde will crumble easily when pinched and will shrink rapidly after heating; it should not be eaten.
Tea
Caution: Dyed with lead-chrome green, beware of colors that are too vibrant.
Identification Method: Lead-chrome green is an industrial pigment that is toxic. Normal "Bilochun" tea has a relatively soft and vibrant color, while "Bilochun" tea with added lead-chrome green looks dark, green, bluish, or dull. After being brewed with hot water, normal "Bilochun" tea looks soft and bright, while dyed tea appears more yellowish and dim. Additionally, normal "Bilochun" tea has fine white hairs on the leaves, whereas the hairs on dyed tea are green.
Dried Tofu Sheets (Yuba)
Caution: Contains "Sodium Sulfite" (a bleaching agent).
Identification Method: "Sodium Sulfite" is an industrial whitening agent. Unscrupulous people illegally add this toxic substance to dried tofu sheets to make them whiter, improve their gloss, and increase their toughness. "Sodium Sulfite" can improve the appearance and taste of food, but it decomposes into highly toxic carcinogenic substances when heated. Qualified dried tofu sheets are light yellow, with protein in a fibrous structure; you can see the fibrous tissues when held against the light. Squeeze it; easily broken tofu sheets are of better quality. Soak a few pieces in warm water; if they become soft and the water is light yellow and not turbid, it is high-quality tofu sheet.
Daylily (Dried Lily Buds)
Caution: Sulfur-fumigated, an enchanting color is abnormal.
Identification Method: To extend storage time, unscrupulous merchants use sulfur to fumigate "old stock," making it appear fresh and dry. Dried daylily with excessive sulfur dioxide is often light yellow or white. Because the color of daylily should become darker through the process from fresh to dried, "enchantingly colored" dried daylily is mostly severely exceeding sulfur dioxide standards. Its light yellow or light white appearance is abnormal, and it has a pungent sour smell. Before eating daylily, it is best to soak it in clean water for more than 30 minutes, then rinse it several times with clean water.