Generally, cooking doesn't put too much oil. As long as you watch the pot smoke, you can fry the dishes in the pot. When cooking, there is a lot of oil in the pot, so it is not easy to measure the temperature of the oil with a thermometer. You can only judge by feeling.
After the oil in the pot is heated, put the food to be fried into the oil. When it sinks to the bottom of the pot and then floats to the oil surface, the oil temperature is about 160℃. If you are cooking shredded vegetables, such as shredded yam, shredded sweet potato and shredded potato, it is more appropriate to fry with this oil temperature. At this time, it is necessary to control the fire under the pot and keep the oil temperature.
After the oil is heated, put the food into the oil, sink into the oil and float to the oil surface. The temperature of this oil is about170 C, which is more suitable for frying crispy chicken and crispy duck. The fried chicken and duck are tender outside. When frying, the fire at the bottom of the pot should also be controlled.
If the food to be fried does not sink oil, the temperature of this oil is about 190℃, which is more suitable for frying various dishes with less water, such as dry frying hairtail, dry frying yellow croaker and dry frying tenderloin.
About 100% oil temperature
Cookies usually describe the oil temperature as "a few percent" hot. I have a material that makes a detailed textual research and discussion on it. Here, I only give you the mathematical relationship between 100% oil temperature Fahrenheit scale and centigrade scale for your reference.
(Fahrenheit = ℃× 9/5+32))
Because the temperature scale of 100% oil temperature belongs to the temperature scale method of chef's experience estimation, its estimation error often varies from person to person, and generally half (10- 15℃) error is allowed. And because of the different flash points of various oils, the temperature of the same oil is different for different oils.
Here is just a reference for you. There are many times of cooking. After you have some experience, you can roughly estimate it. But don't treat cooking as an experiment. Once you use a thermometer every time you cook, it will be too hard and you will lose the fun of cooking.