Why are sweet potatoes hardened or hardened?

When we eat boiled sweet potatoes, sometimes it will be unhappy because the peel of potatoes has to cut away large pieces of potatoes, the remaining one is not much to eat, still has a bitter taste . Sometimes, the boiled sweet potato will not be tender, it will still be hard, peeled away and cannot eat. This sweet potato is the kind of potato we are talking about.

Sweet potato has been crushed.

The first type, sweet potato, is considered to be caused by pests and diseases, called haemophagus from abroad. After the sweet potato is harmed, the small black spots at first gradually develop into big round black spots, without the law of boiling, they have a bitter taste, cannot be eaten, and animals are poisoned. When severe disease spread the whole sweet potato.

The latter type of sweet potato that is waterlogged due to being absorbed by water, creates stagnant water also called 'hard potato' or 'hardened heart'. Sweet potato roots after soaking in water, so as not to let water soak, the insoluble fruit glue of the organization in the sweet potato's body will increase, the cell membrane thicker. Once freed from the threat of water, the insoluble glue does not diminish, and the thickened cell membrane does not thin, eventually becoming a wall of water and water. Boiling also produces resistance to water, resulting in a waterlogged sweet potato.

The two types of sweet potato are both inedible and inability to breed, seriously affecting the product. If when stored, mixed into the sweet potato is really a ' moth- laden soup' , a sweet potato has been used to make the surrounding sweet potatoes also spoil, causing great damage.

So before storing, we strictly select the bad sweet potato tubers away so as not to spread to other tubers.

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