After eating fried dough sticks for so many years, everyone knows that fried dough sticks are fried together, but do you know why? When I was waiting in line to buy breakfast in the morning, someone asked the breakfast master: Why do you want to stick two noodles together and fry them? The answer I got surprised me: the reason why two sticks are fried together is because the fried fritters can't expand if they are fried alone!

Yu Zi Sangkop, Master of Food Science: When the oil temperature is high, the surface contacting the oil will quickly set to prevent expansion, while the soft and unshaped contact surface between the two fried dough sticks can continuously expand outwards, so the expansion effect of the two noodles together will be better. When the oil temperature is low, a single fried dough stick can fully expand before the outer layer hardens.

There is also an allusion to fried dough sticks. It is recorded in the "Clear Barnyard Notes" that fried dough sticks are called "fried ones" in many places: "Fried ones can be as long as one person, and the two pieces are twisted into one, such as rope frying. At first, they are human-shaped, second-hand and second-footed ... Song people hate Qin Gui. Therefore, at present, it is speculated that fried dough sticks originated in Qin Gui's time, that is, the Southern Song Dynasty. In the historical evolution of fried dough sticks production, fried dough sticks have many names. Some are called "fried fruit" or "fruit", and some are called "tianluojin". During Xianfeng period, Zhang Linxi's Trivial Notes even sorted out the names of fried dough sticks in various places: "Fried noodles are like cold utensils, and all provinces in the north and south eat this snack, or call it fruit, or call it oil embryo, while in Henan, it is called sesame sugar and oil steamed buns, that is, the fried ghosts in the capital." Fried dough sticks were in Beijing at that time, and they were called "fried ghosts".

The reason why the fried dough sticks can expand is that the swelling agent added to the dough blocks will react chemically during frying, and a large amount of carbon dioxide and ammonia will be emitted instantly, which will make the dough blocks expand in just a few seconds and finally set. Although the smell of ammonia will make people uncomfortable, because ammonia is soluble in water, the composition of ammonia in fried dough sticks is relatively small. When gas is generated, the expansion of dough depends on the elasticity and ductility of gluten in it. Gluten is the water-insoluble protein in flour. Making deep-fried dough sticks requires especially malleable flour, because they need to be elongated before being put into the pot to increase the heating area.

⑥ In addition, you should be careful at every step in the process of making fried dough sticks. She said that if you accidentally press the edge of the dough piece when stretching the dough piece before cooking, it will affect the final expansion effect of the fritters. In the frying process, the chef also needs to constantly flip the fried dough sticks to make the dough pieces evenly heated to ensure a good appearance.