The person who invented frying is such a genius. Can icicles and beer be fried?

As the weather gets colder, many people fall in love with fried foods . Fried foods can certainly bring satisfaction and warmth in winter, but high calories also bring the risk of weight gain. So is there a food that can be fried but not high in calories?

Someone saw the icicles hanging from the eaves and had an idea: could they be used to cook? (Wouldn't it be a waste of calories and make you "die of weight"?) There really is such a dish, and not only that, there are other strange fried foods...

Fried icicles

I don't know how many people have watched the TV series "Crossing the Guandong". It mainly tells the story of a group of Shandong people who left their hometown and opened a restaurant in the Northeast to make a living. Since they are opening a restaurant, they must cook, but the restaurants in the Northeast are a little different, that is, there will be a sign in front of the door. One sign is called a snack shop, which can only cook simple meals; two signs mean that you can order dishes but only the dishes on the menu; four signs are amazing, indicating that the restaurant is proficient in all cuisines and must be able to cook as long as the customer orders.

In the show, the restaurant has four signs, which lead to some very strange dishes. For example, in one episode, someone went to a Shandong restaurant to make trouble and insisted on making a dish called "deep-fried icicles". You know, ice cubes and hot oil equals to a fried kitchen, which is a dish that goes against common sense. But they actually made it, and it was praised as " cool, fragrant and crispy ".

Hearing this, you may think this is a Shandong dish? No, no, no, this is actually a famous dish from Northeast China. In the cold winter, the snow on the eaves melts and drips under the sun, but because the temperature is still very cold, it will naturally freeze into icicles hanging on the eaves over time. Break it off, coat it with flour paste, and fry it.

It looks simple, but it is not easy to make. First, coat the icicles with flour. Cut the freshly picked icicles into pieces and coat them with flour. However, they are not coated with flour paste directly. Instead, they are frozen in the refrigerator for a while . When the flour coating is formed, put it into the prepared batter to form a second layer of batter coating. As the coating is formed quickly, it can be fried in a pan.

The most difficult step is the fire. After all, the melting point of ice is very low. If the fire is too high, the inside will melt and it will become a lump when you take it out. If the fire is too low, the coating on the outside will not be crispy. When the icicle floats out of the oil pan and the coating is golden, quickly take it out, so that it will be crispy and refreshing on the outside and cool on the inside.

With the control of the heat, how can we ensure that the outer coating is cooked while the icicles inside do not melt during frying? In fact, it is because the temperature of the icicles is very low, and the icicles are coated with a layer of flour or flour paste, which is equivalent to adding a layer of insulation to the ice. In this way, even if the frying is at high temperature, the frying time is "short enough" to reduce the heat directly transferred to the icicles, and directly slow down the melting process from the inside .

The short frying time ensures that the outer insulation layer of the ice cube can be heated and cooked quickly, and at the same time, too much heat will not be transferred into the ice cube. Remember the layer of flour coating that was frozen before coating the flour paste? That is to further prevent the transfer of heat. The flour coating forms a protective layer after freezing, which helps to keep the internal temperature low during frying. Moreover, after frying, the flour paste or egg powder paste will become fluffy and hard, and contain a lot of air inside. Air is a better thermal insulation material (compared to metal!), so it also plays a good role in thermal insulation.
Many of our thermos bottles actually have a similar structure. The thermos bottle mainly achieves heat preservation by reducing heat conduction, heat convection and heat radiation . Its design utilizes a vacuum layer and reflective materials . Two layers of stainless steel are used to construct the vacuum layer in the middle, which can greatly reduce heat conduction and heat convection, and the inner wall is usually coated with reflective materials to reduce heat radiation.

Sometimes phase change materials are used to replace the reflective layer, and their working mode is similar to that of our capacitors. Phase change materials mainly absorb latent heat , which refers to the heat absorbed and released due to the change of intermolecular interaction force when the substance undergoes phase change. And latent heat does not change the temperature of the substance, it can make the substance change state at the same temperature.

When the water temperature is higher than the phase change temperature, the phase change material absorbs a large amount of latent heat and changes from solid to liquid; when the temperature is lower than the phase change temperature, it changes from liquid to solid and releases heat to the water to keep it warm.

Now that we know the secret of deep-fried icicles, it is not surprising that deep-fried ice cream, deep-fried popsicles, and fried popsicles have been derived from them. These seemingly unreasonable foods actually contain the most basic physical principles. However, the icicles nowadays are not picked from the eaves. In order to ensure hygiene, they are basically frozen in molds. If you want a different taste, you can use orange juice, grape juice, or directly use popsicles, which saves the step of freezing.

Fried Ice Cream

Are there any other foods that look weird?

Stir-fried pebbles

In Hubei, the dish made with stones is called Suodiu. As the name suggests, it is thrown away after being chewed. This dish has been passed down for three generations, and the stones remain even after people have passed away . There is basically nothing to eat in this dish except for the seasoning. The only thing that can be mentioned is the pebbles! The main component of pebbles is silicon dioxide, followed by a small amount of iron oxide, trace amounts of manganese, copper, aluminum, magnesium and other elements.

Silicon dioxide is a three-dimensional network structure composed of silicon atoms and oxygen atoms. In the crystal structure, the four valence electrons of the silicon atom and the four oxygen atoms form four covalent bonds. The silicon atom is at the center of the regular tetrahedron. Since one silicon atom is connected to four oxygen atoms, and in the crystal, the regular tetrahedron structure is infinitely extended, one oxygen atom is connected to two silicon atoms, so the ratio of the two in the crystal is 1:2 , hence the name silicon dioxide.
The refractive index of silicon dioxide in the visible light range is between 1.45 and 1.47. This high refractive index can be used to make optical components such as optical lenses and reflectors to achieve control and regulation of light paths. At the same time, its high transparency of more than 98% is also one of its advantages in making high-quality components. Even optical fiber broadband, which is indispensable in modern communications, cannot do without silicon dioxide.

As the raw material of many optical instruments, silicon dioxide has a melting point of 1723℃, which means it does not turn red even when melted in a pot. In addition, silicon dioxide has stable chemical properties and does not react with water. It has high hardness, high fire resistance, high temperature resistance, small thermal expansion coefficient, high insulation, corrosion resistance and unique optical properties.
It can be seen that excellent materials are not only durable and hard to make, but also hard to eat . When the pebbles have lost their flavor, they can be thrown back into the pot and reused, which is a recycling and sustainable development. They are not only used in our daily lives, but also eaten.

Since pebbles are so stable, they basically only physically damage the pot and have little chemical attack on humans, so how do humans make this dish? Stir-fry the onion, ginger, and garlic, add star anise, cinnamon, bay leaves, dried peppers, chili peppers, and rock sugar, and then add the pebbles. Usually, the universal sauce that is said to be fragrant even when stir-frying shoe soles can be used to stir-fry pebbles. It is really amazing.

Now that we have the domestic ones, let's turn our attention to foreign ones. In Texas, the United States, there is a creative food award at the state fair every year. For four consecutive years, fried foods have won the award. They are fried cola (mix the batter with cola, and eat it after frying), fried latte, fried butter and fried beer.

Fried beer

The method of making fried beer is different from that of icicles. It uses salted dough to shape hollow wontons, then adds beer to the wontons, and then throws them into the oil pan and deep-fries them for 20 seconds. However, the taste of this fried beer does change a bit.

The alcohol and some volatile substances in beer will evaporate during the frying process, which will reduce the original flavor of the beer. At the same time, the bubbles in the beer will evaporate after heating, making the maltose and bitter compounds more prominent. The high temperature after frying will cause a chemical reaction between the protein and sugar in the beer, the Maillard reaction. Eventually, brown or even black melanoidins or pseudo-melanins will be generated, giving the beer a unique aroma of frying.

During the frying process, the air in the batter expands due to heat and forms bubbles that float to the surface of the batter. At the same time, the water inside evaporates rapidly under high temperature, and these bubbles push outward from the inside of the batter, making the inside of the fried crispy skin porous, and the oil will flow into the crispy skin along these structures . Friends who love fried food know that the more oil there is in the crispy skin, the more delicious it will be. But did you know that beer can make the fried crispy skin more delicious and crispy?

Studies have shown that adding beer to batter generally increases the oil absorption of the batter by 18% . Researchers prepared and characterized batters with and without beer replacing water in the recipe, and instrumental structural analysis showed that beer batter generally reduced hardness and increased brittleness. The increase in oil absorption results in a slightly softer and crispier texture of the batter, and is more pronounced in rice batter than in wheat batter.

Effect of beer on the hardness (black) and crispness (white) of fried food

In the above figure, RFW represents long-grain rice and water paste, RFB represents long-grain rice and wine paste, MRW represents mixed rice and water paste, MRB represents mixed rice and wine paste, WFW represents wheat and water paste, and WFB represents wheat and wine paste. From the figure, we can see that after adding beer, the hardness of the crispy skin becomes lower, but the crispness increases.

Therefore, the skin of the fried beer wontons will be more crispy, and the beer will also give the beer some of the unique aroma and taste of fried food. It is also common to add alcohol to the batter. For example, fried mushrooms or fried eggplant boxes need to add beer to increase the aroma and flavor of the food. Because the bubbles and alcohol in the beer will make the batter softer and fluffier during the evaporation process, after frying, the outside is crispy and the inside is tender, and the aroma is overflowing. Even for someone like me who doesn't like eggplant, it makes my mouth water.

I wonder if any of my readers have ever eaten any strange dishes. Why not share them in the comments section so that we can all have fun together.

Planning and production

Source: Institute of Physics, Chinese Academy of Sciences (ID: cas-iop)

Editor: He Tong

Proofread by Xu Lai and Lin Lin