INTRODUCTION
As a food product fries, the internal cells become dehydrated and the evaporated water is partially replaced by the frying oil. The mechanism of oil infiltration is still not fully understood.
Gamble et al. (1987a) indicated that as the product fries, the inner moisture is converted to steam, creating a pressure gradient as the surface dries out and causing the oil to adhere to the product’s surface and enter the surface at damaged areas. They suggested that most of the oil enters the chip from the adhering oil being pulled into the chip when it is removed from the fryer due to a condensation of water vapor in the pores creating a vacuum. Saguy & Pinthus (1995) suggested that as the water is evaporated from the product during frying, the rate of oil absorption increases due to a reduction in the pore internal pressure.