Who knows why dumplings float up when cooked?

Then there is a large number of bubbles after the water is boiled, and the bubbles are lighter than the water and float upwards from the bottom, and the buoyancy of many bubbles pushes the dumplings up, and we look like the dumplings floating.

It turns out that the reason why the dumplings float up after cooking is that the water in the pot and the dumplings slowly heat up as the stove heats up. We know that hot objects swell, and dumplings are no exception.

After the dumpling filling and dumpling skin absorb the heat, they gradually expand, and the volume naturally increases a lot, but the mass of the dumpling does not increase, and when the volume increases, the mass per unit volume decreases. When the dumplings are cooked and the dumpling filling and wrappers are fully expanded, their density is less than that of water, so they float on the surface of the water.

Why do dumplings float when cooked, and only those that float are cooked? This is the second question.

It turned out that as the stove heated, the water and dumplings in the pot slowly warmed up. We know that hot objects are meant to expand. Dumplings and water are no exception.

However, the degree of expansion of objects by heat is different, some things expand quickly, and some things expand slowly. Dumpling fillings and wrappers expand faster than water, and their volume easily increases considerably. At this point, you must be very clear that cooked dumplings are indeed swollen and filling, much larger than raw dumplings.

However, because the weight of the dumplings did not increase, and when the volume increased, the weight per unit volume decreased. According to Archimedes' principle, a dumpling immersed in water loses the weight of water of the same size as it, and this lost weight is the buoyancy of the water on the dumpling. Since the dumplings are larger, the weight lost in the water is also larger, that is, the buoyancy of the water on the dumplings is greater than that of raw dumplings.

It is of course not a problem to use a larger buoyancy than the original to float a dumpling with a smaller unit volume and weight than the original. Therefore, only after the dumplings are cooked, that is, the dumpling filling and dumpling skin are fully expanded, can they float. Eating floating dumplings, of course, there will be no worries about sandwiching.

After the dumplings are cooked and float, why do they sink again when they are a little cold? What used to expand quickly must also shrink quickly. When the water cools down, the shrinkage of the dumplings is much greater than that of the water.

After shrinking, the weight per unit volume of dumplings increases again, and the buoyancy of the water also decreases. After the reduction, the buoyancy is no longer enough to float the dumplings with the increased weight per unit volume, and the dumplings sink to the bottom of the pot.

Therefore, in such a small matter as the ups and downs of dumplings, there are so many big truths.

Dumplings or meatballs contain trace amounts of air and carbon dioxide inside during the preparation process. When it is just thrown into the water, because the density of the dumplings or meat nine is greater than that of water, the buoyancy is less than the weight, and it sinks to the bottom of the pot. When heated to cooking, the internal gas and meat mass expand at the same time, and the volume of the whole dumpling or meat nine increases a lot, which also increases its water displacement.

According to Archimedes' principle, the buoyancy of a dumpling or meatball increases, and the buoyancy is greater than the weight, and it floats. ]

Raw dumplings are denser than water, and they will naturally sink when placed in water. With the increase of water temperature, the dumplings and the skin will gradually expand after absorbing the hot water, and the volume will increase, especially the air in the filling will expand greater, the volume of the whole dumpling will increase, the density will become smaller, and the dumplings will begin to float. ]

When the dumpling is fully expanded, the buoyancy is greater than the gravitational force, and the dumpling will float up

1. Density: When the dumplings are not cooked, the average density of the dumplings is greater than the density of water, so the dumplings are sinking; When the dumplings are cooked, the volume of the dumplings increases due to the water vapor inside, and the average density of the dumplings decreases.

2. Buoyancy: After the dumplings are cooked, the volume becomes larger, and the volume of the drained water becomes larger, according to Archimedes' principle, the volume of the drained water becomes larger, and the buoyancy is greater than the gravity, so the dumplings float.

First, it is coarse and dense.

When the dumplings are not cooked, the average density of the dumplings is greater than the density of water, so the dumplings are sinking; When the dumplings are cooked, the volume of the dumplings increases due to the water vapor inside, and the average density of the dumplings decreases at this time, and when the average density of the dumplings is less than the density of the water, the dumplings are in a floating state, so the cooked dumplings will float.

2. Buoyancy. After the dumplings are cooked, the volume becomes larger, and the volume of the drained water increases, and according to the Archimedes principle, the volume of the drained water becomes larger, and the buoyancy is greater than the gravity, so the dumplings float.

Boiled dumplings float mainly because of the change in density and buoyancy.

1. Density: When the dumplings are not cooked, the average density of the dumplings is greater than the density of water, so the dumplings are sinking; When the dumplings are cooked, the volume of the dumplings increases due to the water vapor inside, and the average density of the dumplings decreases at this time, and when the average density of the dumplings is less than the density of the water, the dumplings are in a floating state, and the cooked dumplings will float.

2. Buoyancy: After the dumplings are cooked, the volume becomes larger, and the volume of the water discharged in the branch posture becomes larger, according to the principle of Archimedes, the water volume becomes larger, and the buoyancy is greater than the gravity, so the dumplings float.

1. Density. When the dumplings are not cooked, the average density of the dumplings is greater than the density of water, so the dumplings are sinking; When the dumplings are cooked, the volume of the dumplings increases due to the water vapor inside, and the average density of the dumplings decreases at this time, and when the average density of the dumplings is less than the density of the water, the dumplings are in a floating state, so the cooked dumplings will float.

2. Buoyancy. After the dumplings are cooked, the volume becomes larger, and the volume of the drained water increases, according to the Archimedes' principle, the volume of the drained water becomes larger, and the buoyancy is greater than the gravity, so the dumplings float.

The cooked dumplings will float because the volume has become larger, and the average density of the dumplings is greater than the density of water before the dumplings are cooked, so the dumplings are sinking.

When the dumplings are cooked, due to the lack of water vapor inside, the volume of the dumplings increases, and the volume of the discharged water becomes larger, according to the Archimedes' principle, the volume of the drained water becomes larger, and the buoyancy is greater than the gravity, so the dumplings float.

Boiled dumplings float mainly because of the change in density and buoyancy.

1. Density: When the dumplings are not cooked, the average density of the dumplings is greater than the density of water, so the dumplings are sinking; When the dumplings are cooked, the volume of the dumplings increases due to the water vapor inside, and the average density of the dumplings decreases at this time, and when the average density of the dumplings is less than the density of the water, the dumplings are in a floating state, and the cooked dumplings will float.

2. Buoyancy: After the dumplings are cooked, the volume becomes larger, and the volume of the drained water increases, according to the Archimedes' principle, the volume of drained water becomes larger, and the buoyancy is greater than the gravity, so the dumplings float.

In the process of boiling dumplings, because there is gas in the dumplings, they will slowly expand after being heated to make the dumplings larger, and the mass basically does not change at this time, so the dumplings will slowly increase and eventually float due to buoyancy.

However, floating is not the same as cooking, and cooked does not necessarily float.

After the dumplings are cooked, they will float up and roll the slag, because of the density, the density of the uncooked dumplings is greater than the density of the water, so they will sink, and when they are cooked, they will be filled with water vapor, and the dumplings will become larger in volume and less dense than water, so they will float on the water. When cooking dumplings, wait for the dumplings to float on the surface of the water, indicating that they are cooked.

The reason why the dumplings are cooked and float up.

Dumplings are a kind of food that people like to eat very much in daily life, some people will also buy quick-frozen dumplings and continue to cook and eat by themselves, when cooking dumplings to see dumplings floating on the water, they know that they have been cooked, what is the principle at this time?

The reason why dumplings will float up after being cooked is actually because of the stupidity of the density, when the dumplings are not cooked, the average density is greater than the density of water, and the dumplings will sink at this time, and when the dumplings are cooked, the inside is filled with water vapor, and the volume of the dumplings will also become larger, at this time the average density of the dumplings is smaller than the water, so it will float on the water.

Boil dumplings in a pot under cold water or hot water

If it is a quick-frozen dumpling, the pot under cold water will be better, so that you don't have to worry about the dumpling skin pig, this cooking time is shorter, if you use hot water, it will cause the skin to be cooked, but the meat inside is not cooked, the cooking time is longer, and it is easy to break the skin.

If you cook under cold water, the dumplings are easy to paste off, revealing the filling inside, which not only affects the appearance, but also the taste is not very good.