Sweet potato will not produce harmful components like potatoes after germination, as long as the long buds on sweet potatoes are removed, it can be eaten. However, it should be noted that the sweet potato will not only taste bad, but also lose its edible value because of the massive loss of nutrition and water after it has sprouted.

However, although sweet potatoes can be eaten after germination, if the skin is brown or black spots, it can't be eaten, because it is polluted by black spot bacteria. The toxin released by Alternaria alternata contains sweet potato ketone and sweet potato ketone alcohol, which makes sweet potato hard and bitter. Although this toxin is boiled and roasted, its biological activity will not be destroyed.

Buy sweet potatoes, generally choose sweet potatoes with clean, smooth, good shape, hard and shiny appearance; Don't buy sweet potatoes with sprouted and uneven surfaces, which means they are not fresh; If there is a small black hole on the surface of sweet potato, it means that the inside of sweet potato has rotted.

Sweet potato storage method

1, indoor storage: sweet potatoes are afraid of cold, and when the temperature is too low, they will be frozen, forming a hard core, which is not cooked and boiled; If the temperature is too high, it will sprout again. It is best to control the room temperature at around 15℃. Sweet potatoes are wet, which can easily cause germs to invade and rot. It is best to keep them in a breathable wooden box.

If there are no wooden cases, wooden boards should be put on the place where sweet potatoes are stacked and against the wall, and something should be covered on the potato pile to prevent them from getting wet. In warm days, it is necessary to properly open the window for air exchange to keep the indoor air fresh and prevent cold air from blowing in. The sweet potato bought from the market had better be put in the sun for several hours to reduce the moisture in the wound and promote healing. When taking it, handle it with care to avoid being bruised.

2. Pit storage: Select a place with high terrain, solid soil and low groundwater level, and dig a shaft downwards, with a general diameter of about 1 m and a shaft depth of 5 ~ 6m. The size of the storage room can be determined according to the storage capacity. The storage room should be padded with10 ~15 cm thick dry sand, and sweet potatoes should be placed on it. Sweet potato can only be filled to 70% full, so as to leave room for air exchange, otherwise it will be aggravated by dampness and heat.

3, slice drying preservation method: slice the sweet potato and put it in the room or in the sunny, dry and ventilated place to dry. Be careful not to get caught in rain and snow. After drying in the sun, store it in a dry place indoors and soak it in water before eating.