How many times can you use the same olive oil for frying?

How many times can you fry with the same olive oil? Researchers at the University of Jaén have implemented an innovative artificial intelligence system to answer such questions. They created a model that determines the maximum number of frying times before the undesirable substances generated in the cooking process reach a limit. Current legislation only dissuades the use of oils with more than 25% of compounds that make vegetable fat unusable.

“What we do first is analyze variables that have to do with the quality of the olive oil used, including acidity, peroxides and polyphenols, with the food to be fried and its frying process, including temperature, time and quantity,” explains Antonio Jesús Rivera, one of the directors of the Intelligent Systems and Data Mining (SIMIAT) research group at the university.

The second step is to model the usable life of olive oil according to its storage conditions. The model predicts the oil’s evolution using variables such as the type of oil and the characteristics of the container. “We take into account the existing models, determining the importance of the variables and predictors on the oil’s quality,” says Dolores Pérez, one of the other coordinators of the study.

The study will continue until October 2024. It began from a standard model that it seeks to confirm: “Experts say that a refined sunflower oil can be used to fry up to 20 times, but with extra-virgin olive oil, it can be up to twice as much,” says Rivera, who adds that the uses also depend on the foods being fried.

Cooks who use high-quality extra-virgin olive oil tend to reduce that number. They typically use the same oil four or five times, eliminating the residue after each use, as long as the oil has not burned. Regulators note that the oil will get dirty more quickly when frying loose foods, such as fritters, than when frying potatoes.

There are other recommendations to consider, including not mixing extra-virgin olive oil with other fats that have a lower tolerance for heat. Experts also recommend avoiding sudden changes in temperature and to fry slowly, especially if the food is frozen or very cold. Oil that is not burnt or altered can be reused after the sediment from the previous usage is filtered with a strainer.

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