Why are some sweet potatoes rotten or hard?

When we eat boiled sweet potatoes, sometimes it will be fun because peeling potatoes have to cut off large pieces of potatoes, one sweet potato is not much to eat, and has a bitter taste. Sometimes the whole boiled sweet potato is not soft, still hard, peeled and can’t be eaten. This sweet potato is the type of potato we are talking about.

Why are some sweet potatoes rotten or hard?
Sweet potatoes are spoiled.

The first type, sweet potato, is considered to be caused by pests and diseases, called foreign-transmitted sweet potato disease . After the sweet potato is damaged, the small black spots at first gradually develop into large round black spots, without the rule of boiling, have a bitter taste, can not be eaten, animals are poisoned. When the disease is severe, it spreads to the sweet potato vine.

The type after the waterlogged sweet potato is caused by being soaked in water, creating stagnant water, also called hard or “hard-hearted” sweet potato. After soaking the roots of sweet potato with water, in order not to let water in, the insoluble colloidal substance of the organization in the sweet potato stem will increase, the cell membrane will be thicker. Once free from the threat of water, that insoluble colloidal substance does not decrease, moreover, the thick cell membrane is not thinned, eventually becoming a “wall” against water and water. Boiling also produces water resistance, resulting in waterlogged sweet potatoes.

The above two types of sweet potatoes are both inedible and cannot be propagated, seriously affecting the product. If, when stored, mixed with sweet potatoes, it is really a “worm that makes the pot of soup” , one tuber has to, but it also makes the delicious sweet potatoes around also spoil, causing great damage.

Therefore, before storing, we strictly select the bad sweet potatoes to discard so as not to affect other tubers.