Because the cooked yam has been peeled and completely exposed to the air, an enzyme contained in the yam will react with oxygen in the air to generate brown pigment and melanin, even if the cooked yam is placed in the freezer, it will turn black or even deteriorate.

If you don't eat yam immediately after you buy it, you should handle it properly immediately to ensure the quality and taste of yam remain unchanged. Raw yam should be peeled and cut into pieces, and then packed in plastic bags according to each consumption. After packaging, put it on the top of the refrigerator for quick freezing. You don't need to thaw when eating, just boil the water, which is convenient and can ensure the quality of yam.

The benefits of eating yam include:

1, lose weight. Yam contains less calories, more nutrients and rich crude fiber, which is easy to increase people's satiety and control their desire to eat. Moreover, the fat content of yam is very low, with only 0.2g fat per100g yam, thus achieving the purpose of slimming.

2, improve cold hands and feet: Chinese medicine believes that cold hands and feet are closely related to physical weakness, while yam black chicken soup and longan yam soup have good nourishing, invigorating qi and nourishing blood, especially suitable for patients with cold hands and feet.

3. Prevention and treatment of ulcer disease. Autumn and winter are the seasons when canker easily occurs or recurs. Modern pharmacological studies have confirmed that allantoin contained in yam is helpful to the repair of gastric mucosa. Fresh yam can be made into yam lentil cake or millet yam cake and eaten after steaming.

People's Network-What should I do if yam turns black? How can we keep yam from discoloring?