a pile of fries



There are 5 phases of degradation that cooking oil passes through during use and these can be identified by the quality of the food fried:

  1. Break-in Oil: White product; no cooked odours, no crisping of the surface; little oil pickup by the food.
  2. Fresh Oil: Slight browning at the edges of the fry; crisping of the surface; slightly more oil absorption.
  3. Optimum Oil: Golden-brown colour; crisp, rigid surfaces; delicious potato and oil odours; optimal oil absorption.
  4. Degrading Oil: Darkened and/or spotty surfaces; excess oil pickup; product moving toward limpness; casehardened surfaces.
  5. Runaway Oil: Dark, case-hardened surfaces; excessively oily product; surfaces collapsing inward; enters not fully cooked; off-odour and off-flavours (burned).


  1. Choose cooking oil of good quality and consistent stability
  2. Store cooking oil under suitable conditions (not in extremely hot areas)
  3. Ensure that no cooking oil past its expiry date is used for frying food
  4. Ensure equipment used for frying is working and is properly designed for the purpose
  5. Select the lowest possible frying temperature whilst ensuring food is cooked through, not overheating oil will make it last longer
  6. Filter the cooking oil in all fryers once a day to remove excessive food particles.
  7. Do not fry different products in the same deep fryer – only potatoes in the chip fryer, chicken in the chicken fryer and fish in the fish fryer.  This will prevent cross contamination of food & tainting.  It will also assist in prolonging the oil life.
  8. Clean all deep fryers as per the cleaning schedules to ensure no food particles are stuck to the equipment and to remove all traces of old oil
  9. Test cooking oil in all deep fryers at least daily to ensure it complies with the required quality standards (Refer to test strip procedure on wall charts & test using colour test strips provided)
  10. Replace cooking oil when it has degraded below the acceptable level
    1. Never mix old & fresh oil, discard old oil & fill fryers with only fresh oil, no topping up.
    2. Provide on cooking oil quality to all staff in hot foods preparation areas


Management Training




Oil Inspection Register