Authors : Priya Agarwal , Vijay Karadbjane & Sabiha Vali
Page Nos : 362- 370
Description :
Deep fat frying is one of the oldest methods of food preparation. The turnover rate of oil,
frying time and temperature affect the deterioration of oil during deep fat frying. The
present study evaluated the changes in smoking temperature of four commonly used oils
viz: Groundnut oil (GNO), Sunflower oil (SFO), Soybean oil (SBO) and Rice Bran oil (RBO),
heated freshly and repeatedly reheated to fry potato chips. The initial smoking temperature
of SFO was highest (242° C) and GNO the lowest (210°C). A progressive fall in smoke point
was observed in all oils with increase in frying trials up to 11th trial of frying. Replenishing
with fresh oil at the 12th trial reflected a slight increase in smoke point of all oils. A highly
significant difference (p=0.00) between the changes in smoking temperatures of oils
subjected to repeated heating in frying potato chips was observed. Paired sample analysis
showed insignificant changes in smoke point of oils until third frying (p=.061) indicating the
suitability of all oils until temperatures attained at third frying (198°C, 238°,238°,212° of
GNO, SFO, SBO, RBO respectively). The smoke point is therefore an important
characteristic for restaurants and housewives in deciding when to change the frying oil.
