Why does kelp fade after soaking in boiling water?

The natural color of black kelp is brown, it belongs to algae plants, it contains chlorophyll and lutein, and when the lutein is destroyed by heating, the chlorophyll is released, and it becomes green.

It is normal for kelp soup to have pale green foam after boiling, because after the kelp is soaked, the blisters will appear because:

1. Kelp grows in the sea and is bitten by sea microorganisms.

2. Kelp contains a large amount of algin, which will produce gas after secondary soaking, causing blisters.

Whatever the reason, bubbles contain gums. Current studies have failed to state that it is harmful to the body, so there is no need to panic.

Kelp is a large marine brown algae plant that grows in low-temperature seawater, which is a seaweed plant, which can be suitable for mixing, burning, stewing, stewing and other cooking methods. Kelp (Laminaria japonica) Brown algae, Kelp family. The sporophyte is large, brown, flattened and band-like, up to 20 m long.

It is divided into blades, stalks and holders, and the holders are pseudoroot-shaped. The leaves are composed of epidermis, cortex, and medullary tissues, and the lower part of the leaves has sporangia. It has a mucus cavity and secretes a slippery substance.

Anchor tree-like branches to attach to seafloor rocks. Grows in the sea with low water temperatures.

It is cultivated in large quantities along the northern coast of China and the coasts of Zhejiang and Fujian, and its output ranks first in the world. Rich in alginate and iodine, it can be eaten and extracted from industrial raw materials such as iodine, alginate, mannitol, etc. Its phyllodes can be used as medicine.

Kelp is a vegetable with high nutritional value and at the same time has certain medicinal properties. It is rich in mineral elements such as iodine. Kelp is low in calories, medium in protein and rich in minerals, and has been found to have a variety of biological functions such as lowering blood lipids, lowering blood sugar, regulating immunity, anticoagulant, anti-tumor, lead detoxification and antioxidant.

Fresh kelp should be dark green, and the flesh is thicker and some are tan. There are two kinds of kelp in the general market, wet and fresh, and some soaked with dried kelp. After soaking for a long time, the kelp will become delayered and the epidermis will fall off, which should cause the so-called fading.

If the kelp is only discoloring on the surface, it may simply be the result of a longer soaking time.

Another possibility is dyed kelp. Dyed kelp is mostly dyed with industrial raw materials, and the main raw material for dyeing is "sodium dithionite."

and "alkaline royal green". "Basic royal green" is a chemical dye for clothing.

"Sodium dithionite" is a stabilizer. Some unscrupulous traders also use sulphur dioxide.

Dye kelp. Regular consumption of dyed kelp can cause precipitation in the body, which may cause cancer.

It may be normal for kelp to fade because it has been soaked for too long.

1.Although kelp grows on the bottom of the sea, it also has chlorophyll, but it also contains lutein, which looks dark yellow only when it looks fresh in lutein.

2.After heating and scalding with water, its lutein is destroyed, and chlorophyll is released, so it will appear green.

Four ways to identify kelp discoloration.

First, the epidermis of the dyed kelp has been rotted by chemical dyes, and it is easy to cut it by hand. However, the skin of fresh kelp is smooth and not easy to break.

Second, the fresh kelp seafood flavor is very strong. The seafood flavor of dyed kelp will be covered by chemical dyes, and the smell of seafood will not be so obvious.

Third, soak the kelp in water and see if it falls green.

Fourth, boil the kelp with vinegar for testing. If the green color is derived from chlorophyll, the chlorophyll will fade to a light olive green color when exposed to acid. If the kelp does not change color, it is clear that the green color is dyed.

There may be two reasons why kelp changes color as soon as it is blanched: one is that chlorophyll is more stable to heat than carotenoids, and in the process of blanching, part of the carotenoids are destroyed, so the green color is revealed; On the other hand, the high temperature has changed the acid-base environment of kelp, and the original yellow-brown demagnesium chlorophyll recaptures metal ions and appears green. It can be seen that it is normal for kelp to turn green when exposed to boiling water, and it is usually a sign of fresh kelp.

This is a normal phenomenon, kelp is mainly high in iodine, but some kelp fades or is green, which may be dyed by unscrupulous traders with stabilizers or dyes.

The reason for the discoloration of kelp: After soaking for a long time, the kelp will stratify and the epidermis will fall off, which should lead to the so-called discoloration.

The reason why the kelp is rotten and broken after being soaked in water is because the kelp has deteriorated, and the spoiled kelp should never be eaten. Excessive water inhalation due to uncontrolled infiltration of kelp cells after rain, mainly floating on the water, or harbor areas where a large amount of fresh water is injected during the rainy season.

Farmed kelp can also be diseased.

When eating kelp, it should be washed and soaked in water according to the actual situation, and the water should be changed continuously, usually soaking for more than 6 hours. If the kelp is not as tough as if it is boiled after being soaked in water, it has gone bad and can no longer be eaten.

Kelp contains alginate and alginic acid. These substances are water-insoluble polymeric compounds with strong water-absorbing swelling properties, and once absorbed, a viscous colloid appears on the surface of the kelp, which prevents further water from leaching. Therefore, kelp is difficult to penetrate, and most of the iodine contained in it is on the surface, and long-term soaking is easy to cause loss.

Because there is sea salt in the kelp to prevent decay, it will rot quickly under the protection of no words, so it is recommended that you wash it before eating it again, wash as much as you eat, and then steam it in the pot for about 30 minutes, and pull it out with cold water after it comes out of the pot.

It was caught from the sea and it was hot, and that kind of kelp was not delicious, and it was sticky in the mouth.

Because dried kelp is processed, not all-natural.

Well, the quality of your kelp is not good.

This should be normal. Because when you are boiling kelp, the kelp will lose a little bit of color. So her water will turn green. He's definitely not the kind of guy who is particularly green, and if it's too green, then there's something wrong with it, and it's normal to cook it and have a normal complexion.

If it was dried before, the pigment will float on the surface after drying, so that when it is cooked, it will appear green under the absorption of water, and I hope it will help you to look forward to it.

Normally, when this kelp dries, its color is a little yellowish, but when it is boiled in water, it turns very green.

Answer: It is normal for dried kelp to soak in water and fade to eat, because there is a layer of viscous liquid on the surface of fresh kelp, even if it is fresh to buy for cleaning, it will fade a little, and there is a layer of white flour on the surface of dried kelp, this is not mold and dried kelp is naturally dried in the physical evidence It is called mannitol, he is a medicinal substance that belongs to organic compounds, which is normal, and the dried kelp will be soaked for a long time, and the kelp will be layered, and some of the epidermis will fall off, which should lead to the so-called discoloration. In one, you have to distinguish whether it is naturally air-dried, some kelp will be chemically treated, and it will fade after many rinsings, so be sure to check whether this kelp has been chemically treated, I will teach you a small trick to buy dried kelp when you first pick it up to see if there is hoarfrost outside, the more hoarfrost proves to be of better quality, and then pick it up and smell it, if there is a pungent sour smell, it is not recommended to eat it if it has been soaked in the potion.

Kelp is a very nutritious food, eat the right ** good, can supplement calcium, can also relieve the stress caused by the exuberant male hormones, etc., but not overeat, should be a small amount of many times the effect is better, this is my understanding, I hope to be, thank you.

Although kelp grows on the bottom of the sea, it has chlorophyll, and it also contains lutein.

After heating and scalding with water, its lutein is destroyed and chlorophyll is released, so it will appear green; On the contrary, if the chlorophyll is destroyed, lutein is released, so it will appear yellow, which is okay and can be eaten.

Expansion: Kelp is a large marine brown algae plant that grows in low-temperature seawater, which is a seaweed plant, which can be suitable for mixing, burning, stewing, stewing and other cooking methods.