05 Jul Olive Oil better for frying
Frying is a simple cooking method used in home and restaurant meal preparation worldwide. There are two types of frying, shallow frying and deep frying. Deep frying results in complete food immersion in fat. While shallow frying is a partial immersion of foods in a selected fat. Shallow frying is generally seen as the healthier option.
Olive oil is a healthier choice of cooking oil for use in either of these frying methods. A recent study, published in Food Research International, aimed to establish how frying fish not only affected the lipids (fats) in the fish but also how the cooking oil changed during the shallow-frying process.
The study looked at two different types of supermarket-bought oils, Olive Oil and sunflower oil. Both oils and fish samples were submitted to two different shallow-frying conditions, a household microwave in a domestic ceramic baking dish operating at 900W; and in a domestic pan.
The oils were first fried in the absence of food and the lipid results extracted. New oil samples were then used to fry fish fillets under the conditions outlined above, in the microwave and in a pan. Domestic temperatures were mimicked for the experiments with an oil temperature of 170°C (340°F) and a cooking time of 2.5 minutes for each fillet side.
The fish were prepared, gutted, cleaned and filleted into roughly 300 g pieces and were of similar dimensions. Lipid extracts were taken from each fried fish sample. There was also fat extracted from one raw sample, acting as the control sample.
The results of the study showed that overall Olive Oil is a more stable cooking oil than sunflower oil for frying fish.
Regardless of the oil used, there is a lipid migration that occurs between the fish and the culinary oil selected for cooking. For instance, Olive oil samples were richer in omega 3 and saturated fats after frying, and lower in oleic groups. The results showed there was a 19 to 28 percent migration of fish lipids across to the fried oils.
As expected, the sunflower oil had a smaller resistance to oxidation and degradation than Olive Oil. Frying or heating in the microwave causes less oil oxidation and degradation than pan frying. However, according to the study, no thermo-oxidation was found in Olive Oil.
The highest oxidation compounds were found in the sunflower pan-fried fish.
The authors concluded that, “the selection of the cooking oil is of paramount importance due to its impact on the fish lipid profile and on the possible generation of toxic compounds in the oil during frying, which can have a great influence on food safety and human health.”
And it appears from their results, OLIVE OIL is the better option of the two.