The main reason for the soup white elements: fat, in practice, with the continuous heating, water convection effect of the soup tumbling boiling, ingredients in the fat by the water molecules into countless small oil droplets dispersed in the soup, the formation of a soup turbid state, the scientific name is called emulsion. Therefore, the selection of carp should be rich in fat, soluble protein, such as pork ribs, pig's trotters, duck, etc. are rich in fat, generally do milk soup will choose these materials. The fish is low in fat, so it has to be fried in oil first to artificially add some fat. At the same time, all of these materials are also rich in protein, and protein plays an emulsifying role in the process of cooking soup.

The key step is to fry the fish thoroughly! Ensure the integrity of the fish body, in order to ensure that the fish soup is white without scum, we must ensure the integrity of the fish body, when dealing with the fish, from the gills of the gills of the fish to take out the internal organs together, and then the gills of the fish, the fish belly above the small scales removed and washed. It is best not to cut open the belly of the fish, so that the simmered fish soup, pure soup, fish meat intact. Heat the pan over high heat, to the high temperature of the oil temperature ignition point under the pan, using the lid to prevent fire and splash oil. Fry until golden brown on both sides, fish head and tail should also be fried through, usually more than ten minutes. If the heat is too high, change the heat to medium-high. After frying, add boiling water, make sure it's freshly boiled, and the creamy fish soup will come out within five seconds.

Many people boil out the carp soup is not white enough, is to add salt "masterpiece", and salt in the high temperature is easy to change into nitrite, is not conducive to health. The best thing is to put a little bit in the final pot.

Tracking down the reason, I think the milky white color is the credit of the fish skin. When I was a kid, I used to make jelly with fish gelatin powder, which is white in color, and the fish skin does contain a lot of fish gelatin, so the milky white color of the soup is due to the fish gelatin. I guess the fish skin is easier to dissolve after frying. Therefore, if the fish is not fried, the soup is not white; if the small fry, fish glue dissolved need to cook a long time; if the fire fry, fish glue is easy to dissolve, a little cooking that is white.