Why does purple sweet potato turn green

Many people have found that the color of purple sweet potatoes changed after being used to make porridge. People wonder whether the purple sweet potatoes that have changed color can be eaten, because more and more foods are being added with substances that are harmful to the body by unscrupulous merchants. Why do purple sweet potatoes turn green? Because purple sweet potatoes contain a lot of anthocyanins, which are water-soluble pigments that can change color due to acidity and alkalinity, it is normal for purple sweet potatoes to turn green when making porridge.

1. Why does purple sweet potato porridge turn green?

Purple sweet potatoes contain a large amount of anthocyanins, which are water-soluble pigments that can change color with the acidity and alkali of the cell fluid. If the cell fluid is acidic, it will be reddish; if the cell fluid is alkaline, it will be blue. It is normal for it to fade and turn blue when exposed to water. For some people, it may turn purple or blue when eaten. This is because the saliva dissolves the purple pigment. This natural water-soluble pigment is not harmful to the human body. Anthocyanin is extremely unstable. It turns red when exposed to acid, blue when exposed to alkali, and purple when neutral.

Purple sweet potato is a crop with high nutritional value. It contains a large amount of anthocyanin, which is an extremely unstable water-soluble pigment that changes color with acid and alkali. It turns red when it encounters acid, blue when it encounters alkali, and purple when it is neutral. If the skin and flesh of the purple sweet potato look purple and not green after being cut, it is normal for the water to turn blue-green after boiling. Don't worry and you can eat it normally. Add some vinegar or lemon juice to turn it back to purple. Generally, alkali is added when cooking porridge at home, so the anthocyanins in purple sweet potatoes appear blue-green in this environment. When some people eat purple sweet potatoes, they will turn purple or blue after chewing. This is because the saliva dissolves the purple pigment. This natural water-soluble pigment is harmless to the human body. Experts from the food website also suggest that purple sweet potatoes can also be cooked in other ways to avoid color changes, such as steaming them, or cutting them into pieces and microwaving them in a microwave. If they are to be boiled, the cooking time should be between 5 and 10 minutes.

2. The efficacy of anthocyanins in purple sweet potatoes

1. Anthocyanins have anti-inflammatory effects and can prevent inflammation including arthritis;

2. Reduce the occurrence of heart disease and stroke by preventing platelet aggregation caused by stress response and smoking;

3. Enhance the immune system to resist carcinogens;

4. Anthocyanins can reduce the frequency of colds and shorten their duration;

5. Anthocyanins can reduce the formation of carcinogenic factors;

6. Helps prevent a variety of diseases related to free radicals: cancer, heart disease, premature aging and arthritis;

7. Anthocyanins also have anti-radiation effects, and most anthocyanins have good light, heat and pH stability;

8. Enhance the elasticity of arteries, veins and capillaries;

9. Protect the inner wall of arteries;

10. Maintaining the normal flexibility of blood cells helps red blood cells pass through tiny capillaries, thereby enhancing blood circulation throughout the body, bringing direct benefits to organs and systems in all parts of the body, and enhancing cell vitality;

11. Relax blood vessels to promote blood flow and prevent high blood pressure (blood pressure lowering effect);

13. Prevent the increase in blood pressure caused by angiotensin-converting enzyme released by the kidneys;

14. Anthocyanins prevent the formation of amyloid beta protein and the attack of free radicals, thus preventing Alzheimer's disease;

15. Inhibit elastase and collagenase, making the skin smooth and elastic.