3rd meeting of young researchers at UP 1 - IJUP - Universidade do ...

Fat uptake by fried foods
A. Costa 1,2 , E. Mendes 2 , S. Casal 2 and M. B. P.P. Oliveira 2
1 Requimte, Instituto Superior de Engenharia do Porto, Rua Dr. António Bernardino de Almeida 431,
4200-072 Porto, Portugal.
2 Requimte, Serviço de Bromatologia, Faculdade de Farmácia, Universidade do Porto, Rua Aníbal
Cunha 164, 4099-030 Porto, Portugal.
Fried foods are largely consumed in Portugal and in Western countries. While their
organoleptic characteristics and easy preparation make them so popular, their association to a
high caloric intake and, consequently, to overweight, obesity and other chronic diseases, raises
some concerns.
In Portugal, sunflower oil is the main raw material used in frying, whether at home or in
restaurants and catering, not only pure but also blended with other oils. Based on the less
positive connotation of frying foods in vegetable oil, the aim of this work was to evaluate the
fat incorporation in different food types during the frying process.
Domestic frying was simulated performing two daily frying cycles (lunch and dinner) in a
deep-fryer, at 180 ºC. The frying period of each cycle was 2 hours. For each assay, oil was
previously heated for 1 hour and, then, fresh potatoes (in sticks), patties and fish sticks were
separately fried.
In addition to fried food analyses (by official methodologies) regarding fat content (%) and
moisture (%), the frying bath quality was also evaluated by determination of polar compounds
as regulated in Portugal (up to 25%), being rejected after 5 days of use (18 hours of heating).
The results showed that the fat contents slightly vary during the frying process, but without a
trend. The levels were 10-15%, for french-fried potatoes, 14-18%, for patties, and 10-12%, for
fish sticks.
In conclusion, the life of the oil does not seem to directly affect the fat content of fried foods.
3 rd meeting of young researchers at UP 347