What are the factors that affect the deterioration of frying oil?

My friend bought it at a company called Rice Field Machinery, and he said it was good.

Here's why:1. According to different food agitation materials, the oil temperature also changes. The ingredients are larger and can be used at medium and high oil temperatures, and the ingredients are smaller in taste, and the taste is fresh and tender, and the branches can be warmed with low oil and lead.

2. When the ingredients are put into the oil pot, you can cover the pot slightly with a lid to avoid being scalded by the splashed oil and reduce the oxidation of hot oil and air.

3. Note that you can't add too many ingredients at one time, and the high-temperature oil pot is more dangerous and difficult to control the ingredients, and the ingredients will be half-cooked due to uneven heating.

The influence of frying time on frying effect: the frying time is too short, the dehydration of the dough is not complete, and it is not easy to store; If the time is too long, the dough will bubble and scorch, which will affect the quality of the dough and increase the cost.

It affects the oil temperature interactingly, the moisture content in the dough is determined, and the oil temperature is low, the frying time is long; The oil temperature is high and the frying time is short.

The oil temperature is too low, and the dough pieces cannot be fried thoroughly; If the temperature is too high, the dough will be scorched. Frying is divided into three stages: in the low temperature zone, the dough blocks absorb heat, the temperature rises, and dehydration begins; Entering the medium temperature zone, the noodles begin to dehydrate a lot, and the oil seeps into the noodles; The water content of the surface block in the high-temperature area has been basically stabilized, and it is no longer dehydrated, and the temperature is similar to the oil temperature.

This increases the gelatinization of the starch and deepens the protein.

Frying principle. When frying products are processed, the oil can provide rapid and uniform conduction heat energy, the surface temperature of the food rises rapidly, the moisture is vaporized, and a dry layer appears on the surface, forming a hard shell. The vaporization layer of water then migrates to the inside of the food, and as the surface temperature of the food rises to the temperature of hot oil, the internal temperature gradually increases.

At the same time, caramelization reaction occurs on the surface of the food, and some substances decompose, resulting in the unique color and flavor of fried food. Food can be divided into five stages when it is fried.

1. In the initial stage, the food is put into the oil until the surface temperature of the food reaches the boiling point of water. There is no significant evaporation of water at this stage, and the heat transfer is mainly natural convection heat transfer. The surface of the fried food remains white, no brittleness, the amount of oil absorption is low, the starch in the center of the food is not gelatinized, and the protein is not denatured.

2. Fresh stage: At this stage, a large amount of moisture on the surface of the food is suddenly lost, and the outer skin shell begins to form, and the heat transfer is mainly heat conduction and forced convection heat exchange, and the heat transfer increases. The periphery of the surface of the fried food is somewhat browned, the starch in the center is partially gelatinized, the protein is partially denatured, and the surface of the food is brittle and slightly absorbs oil. This stage consumes the most energy and takes the longest time, and is the main stage for the formation of texture and flavor of fried food.

3. In the optimal stage, the outer shell is thickened, and the amount of water damage and heat transfer is reduced. Heat transfer is mainly heat conduction, and the air bubbles escaping from the food gradually decrease until they stop. The fried food is golden brown, with good crispness and good flavor.

4. In the deterioration stage, the color of the fried food becomes darker, the oil absorption is excessive, the product becomes loose, and the surface becomes stiff.

5. Discarding stage: The color of the fried food becomes dark black, the surface is stiff, and there is charring.

The above content reference: Encyclopedia - fried.

Categories: Life >> Food Cooking.

Problem description: The reason why the oil temperature should not be too high when frying food is: (

A The oil temperature is too high, which can easily cause the oil to produce a "hala smell".

b. The oil temperature is too high, so that the oil produces substances that are harmful to the human body.

c It is easy to make the taste of fried food unpleasant.

d All of the above statements are correct. Analysis: b

a.If the oil temperature is too high, it is easy to produce a "hala smell".

b.Too high oil temperature makes the oil produce substances that are harmful to the human body (correct answer) CIt is easy to make the taste of fried food bad.

When frying food, it is advisable to control the temperature at 160 and 180, as high oil temperature is not only easy to over-fried, but also easy to produce carcinogens in the spring. If there is a lot of smoke on the oil surface, or if the food changes color too quickly, the temperature is too high.

Do not use the oil for frying food repeatedly, the oil that has been used again and again, the oil used for frying for a long time will produce a lot of harmful substances, it is recommended to change the oil frequently, and remove the impurities in the oil in time no matter how bad it is.

Extended Information: Precautions for frying food:

1. Hanging a layer of starch paste on the outside of fried fish and meat and then frying can also effectively prevent the formation of heterocyclic amines and mutation sources.

2. Fried food and oil residue should not be eaten too much at a time, nor should it be eaten too often. Do not eat fried foods that are dark in color, too greasy, have a bad taste, and have gone moldy and spoiled.

3. The edible oil after frying food should be filtered immediately to remove the decomposition substance, so as to prolong the service life of oil and fat preparation.

4. The edible oil used after repeated frying contains a large number of mutation sources and lipid peroxide, and is inedible.

5. Fried food, it is best to fry and eat it freshly.

6. It is best to use an iron pan to fry food.