Does frequent replenishment with fresh monoenoic oils permit the frying ofpotatoes indefinitely?

The frying life of two monoenoic oils, extra virgin olive oil (EVOO) and hi gh oleic acid sunflower oil (HOSO), used to fry potatoes following a domest ic frying model, by replenishing the oil in the fryer with fresh oil after each use to maintain the oil volume/fresh potato ratio, was studied by meas uring polar content (PC) and triglyceride oligomer (TO) content; A combinat ion of column and highperformance size-exclusion chromatography was used. C hanges in the PC and TO content of both oils according to the number of fry ing uses were adjusted to linear, logarithmic, and power equations. While a ll three equations reflected the alterations quite accurately(p < 0.001), t he logarithmic and power equations defined them best. Frequent replenishmen t of both frying oils with fresh oil produced a stabilization of PC and TO levels after 20-40 uses. According to the linear adjustment equation, 321 /- 33 frying operations with EVOO and 290 +/- 40 with HOSO would be needed to raise PC to 25%. To reach the 10% TO level set for discarding oil used i n Frying, EVOO and HOSO would have to be used 319 +/- 35 and 241 +/- 37 tim es, respectively. Using the power adjustment, however, the theoretical fryi ng life of both oils would be much higher (at least 4460 frying uses before reaching a 25% PC and 538-1552 uses for the EVOO and 249-1319 uses for the HOSO to reach a 10% TO level). The frying life of EVOO and HOSO would be e xtended almost indefinitely (at least 170 000 uses) when the logarithmic ad justment was applied. These data suggest that frequent replenishment of use d monoenoic oil with fresh oil permits one to fry sets of fresh potatoes a very high number of occasions.