There is a saying on the Internet that radishes turn blue because they are placed in a low-temperature environment for too long, and the water evaporates and turns blue. Through experimental observation, white radish slices in low-temperature refrigeration for more than 24 hours, and water evaporation is obvious, did not occur when the phenomenon of blue; water evaporation at room temperature for about 5 hours, but also did not turn blue.
Fan Zhihong, an associate professor at the Department of Nutrition and Food Safety in the College of Food Science at China Agricultural University, said radish blue is a very rare situation. This is actually a natural change in the plant itself.
In fact, radish discoloration is related to the storage conditions and environment, sometimes in the case of cold, the phenolic substances in the radish may be converted into anthocyanins, and anthocyanins encounter alkaline substances will become blue; encounter acidic substances will become purplish red. Therefore radish containing anthocyanins may turn blue if put together with other alkaline foods.
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Tips for picking radish:
1, the skin of a good radish should be smooth and glossy, so that the radish has more water and delicate flesh.
2, buy radish can not be greedy, because too big radish is easy to lose water. Choose medium-sized small is better, this kind of radish flesh is compact, taste better.
3, cracked, forked radish do not buy. Because this is often caused by poor growth and development or overwatering, such radish not only looks bad, poor taste, but also not resistant to storage.