Abstract
To elucidate the influence of a conveyer attached to an auto-fryer on the deterioration of frying oil, the folowing experiments were carried out.
1. As a conveyer model, rotors were constructed to rotate slowly over the frying oil surface. A comparison was made of the degree of deterioration of soy bean oil heated for 8hrs at 180°C with and without the use of the rotors. Observation of the changes in viscosity, acid value and color of the oils showed that the rotors accelarated remarkably the deterioration of soybean oil. Coating of the rotors with Teflon or the use of net rotors in place of plate rotors significantly reduced the thermal deterioration of the soybean oil.
2. The influence of the vessel materials (aluminium and iron) coated with and without Teflon on the deterioration of soybean oil heated at 180°C was investigated. Deterioration was found to be less for vessels coated with Teflon.
