Thereafter, the same sample was reheated, and the entire process
was repeated (frying in reheated/reused fat/oil maintained at
180 C and 220 C, respectively, as described above). Thus, in fat/
oil samples subjected to frying, pre-frozen French fries were fried,
while in the case of heating, the fat/oil samples were subjected to
heating only. For each of the selected fat/oil samples, a total of 4
heating/frying cycles was carried out over approximately 7 h and
at the end of each cycle 30 mL of fat/oil were withdrawn for
analysis.