Purple cabbage soup is green normal, purple cabbage after cooking, purple cabbage is purple, because purple cabbage contains a special pigment protein called "phycoerythrin". Alginin can be dissolved into water. And, this pigment protein is not stable, especially when heat is easy to decompose.

So, in the soup, the loss of phycocyanin of the purple seaweed faded their original purple color, turned green. This is because, in addition to phycocyanin, nori also contains pigments such as chlorophyll, carotene and lutein. Among them, chlorophyll has the highest content. It takes the place of phycoerythrin, which "turns" the leaves green.

Expanded Information

Nutritional value of seaweed soup:

1, prevention of goiter. Can be used for the treatment of iodine deficiency caused by "goiter", nori has a soft knot function, on other stagnant blocks also have a use.

2, promote growth and development. Rich in choline and calcium, iron, can enhance memory, treatment of anemia in women and children, to promote the growth of bones, teeth and health; contains a certain amount of mannitol, can be used as an auxiliary food for the treatment of edema.

3, improve immune function. The polysaccharide contained in purple cabbage has significantly enhance cellular immunity and humoral immune function, can promote the transformation of lymphocytes, improve the body's immunity.

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