Duck eggs take 8 minutes to cook in boiling water and 15 minutes to cook in cold water. If boiling water is used, cook for about 8 minutes. It is best not to exceed 8 minutes. If it exceeds 8 minutes, the nutrition of eggs will be lost to a certain extent. If it is boiled in cold water, it takes about 15 minutes. Of course, if you want to eat half cooked liquid egg yolk, cook it in boiling water for about 7 minutes and cold water for about 10 minutes.
If you cook salted duck eggs, it is generally appropriate to put them in cold water. Cold water doesn't explode easily. Salted duck eggs will slowly "heat expand" inside and outside with the gradual rise of water temperature. When the water temperature is enough to solidify the protein, the eggshell will expand almost, so as not to expand and break the shell.
Put the salted duck egg into the cold water pot, let the water submerge the egg, at least one knuckle over the surface of the duck egg, boil it over the fire, wait for the water to boil, quickly turn it off to a low fire, and keep the water above 90 degrees for 10 minutes (or cook for 7-8 minutes). When cooking cracked eggs, put some salt in the pot first. Salt has a coagulation effect on the protein and can prevent the protein from flowing out. Adding a little vinegar can also prevent the outflow of protein.