What needs to be reminded here is that potatoes and peanuts are not edible when germinated, because germinated potatoes are toxic, and once sprouted, they should be discarded. Don't eat yam if it turns black inside, which means it has gone bad.
How long can yam be preserved?
Any food has its shelf life, and yam is no exception. Its shelf life is determined by the temperature and humidity of the air. If you buy yam in summer, it can only be preserved for two months at most, because the air humidity is high and the temperature is very hot in summer, which is not conducive to preservation. In autumn and winter, the preservation time is relatively long, which can be as long as eight months.
The reason why yam turns purple
I wonder if you have noticed that we will find a problem when peeling yam. The pulp of yam is actually purple, which makes many people puzzled. What is the reason?
1, variety
There are many kinds of yam, among which the iron yam is purple, that is, when we peel the yam, a layer of lavender will appear. This is a normal phenomenon, so we don't have to worry about it, and we can eat it with confidence.
2. Temperature
The oxidation of yam is very intense, especially in winter, when the temperature is too low, when the skin of yam is removed, we will see purple pulp, which is not necessary to worry about. When the temperature rises, the color will be normal.
3. Oxidation
The color of yam will definitely change after peeling, and we often find that it will turn black. This is because the polyphenols in yam will be oxidized when they meet with air, which will produce melanin and change color. Therefore, when handling yam, it must be soaked in water to avoid contact with air.