Go to the supermarket, the market, the color of the beautiful vegetables will always be able to make you pleasing to the eye, normally, the more brightly colored food the fresher, but not all the food is, let’s take a look at the following five kinds of food. 1, too white portobello mushrooms, lotus root Fresh portobello mushrooms are easy to bump in transportation, generally will not be uniformly pure white, but beige, there are bruises are light brown. When we buy, we see that the color is too white and too bright mushrooms may be soaked with fluorescent whitening agents, it is best to buy with a little bit of soil, the body of the mushroom is not smooth with a little bit of scales, the root of a little bit of browning. In addition, the sale of lotus root may also be bleached, lotus root is also easy to change color affecting the “look”, some vendors will use dilute sulfite solution for bleaching, so do not just focus on the appearance of lotus root is clean and therefore “fooled”. 2, both sides of the black fungus When shopping for fungus, it is best not to choose both sides of the black, one side of the brown side of the gray better. The real black fungus front black-brown, back gray-white, while the ear is yellow-brown, the price is much cheaper than the fungus. Some unscrupulous traders in order to increase the weight of the fungus, will use the chemical reagent magnesium sulfate soaked fungus, was soaked fungus both sides were dark brown, can not see the front and back. The taste of black fungus is very natural, there is a fragrance, and adulterated fungus has the stench of ink. In addition, the real fungus chewing fragrant and delicious, and after the magnesium sulfate soaked fungus and bitter and astringent, difficult to swallow. 3, too green kelp kelp from the sea just fished out when it is indeed green, but after drying it becomes black, many manufacturers or restaurants because of this bad look, will add copper sulfate soaked kelp, the principle lies in the copper ions in the kelp chlorophyll in the magnesium ions instead of so processed, the kelp will become green. Industrial copper sulfate contains heavy metals lead and arsenic, consumption will produce great harm to the human body, although there is food-grade copper sulfate, but for kelp such as direct entrance to the product, it is not allowed to be added. 4, too white pistachios domestic sales of pistachios from California. Many merchants in the import of pistachios in order to extend the shelf life of the product, and make it look better, before the sale of pistachios bleached. Most consumers are unaware of the true appearance of pistachios and mistakenly believe that white is the natural color of pistachios. In reality, unbleached pistachios should have a natural creamy yellow color. When we buy pistachios should have milky yellow shells, purple fruit coat, green kernels three major features belong to the quality of pistachios. And long-term consumption of bleached food, the residual bleaching ingredients will produce gastrointestinal irritation injury. 5, too red cooked food Fresh meat cooked in boiling water is dark in color, a little grayish color. We see in the market some meat cooked food color looks very bright, this meat may be artificially added nitrite. In accordance with domestic food safety standards, ham in the production, in order to achieve the role of antiseptic color, allowed to add a moderate amount of nitrite, however, cooked food is prohibited to add nitrite, so we usually buy, encounter bright color, taste close to the ham meat, we must be careful to choose.