The oil used to fry food should not be reused because its reuse increases the formation of acrolein, a substance that increases the risk of diseases such as irritation of the intestine and cancer. In case of repeated frying, special care should be taken to reduce the production of acrolein.
The formation of acrolein occurs when the oil is subjected to very high temperatures, as the fat undergoes changes and loses quality. This degradation happens even with the most beneficial oils for health, such as olive oil and fish oils.
Care to be taken while frying
The following are some of the care you should take during the frying process to reduce oil breakdown, increase oil life, and reduce the formation of toxic substances:
- The maximum temperature that the oil should reach is 180ºC. A sign that the temperature is too high is when the oil emits smoke;
- It is better to fry for long periods of time than to make several small fries;
- At times of frying, the fryer / skillet / pan should be capped so the oil does not come in contact with the air;
- You should avoid mixing old oil with new oil;
- The oil should be filtered at the end of each fry to remove loose pieces of food. To filter the oil, coffee filter or gauze may be used, for example;
- Between one fry and another, the oil should be stored in covered containers protected from light, and if the interval between uses is long, the oil should be placed in the refrigerator;
Fryers / pans / pans should have rounded corners as this facilitates cleaning and prevents the accumulation of old food and oil debris.
Signs that the oil should be replaced
How long the oil can be used depends on the amount of frying that has been done, the temperature the oil has reached, and the time it has been heated. The signs that the oil needs to be discarded are:
- Formation of foam or smoke during frying;
- Intense browning of oil or food coloring;
- Strange smell and flavor of oil or fried food.
Even when you take care during frying, this process adds fat to foods and forms health-damaging substances, avoiding fried foods and giving preference to grilled or baked foods.
Olive oil is the ideal fat to put in salads and finalize culinary preparations, so see how to choose a good olive oil.
