Over the past 5 years growing demands for reducing fat content of fried foods have greatly stimulated the amount of research spent on the issue of fat uptake during deep-fat frying. The results of these efforts are summarized in this review. Most of the increased understanding of the mechanism of fat uptake has been brought about by improved imaging techniques. It turns out that fat uptake is basically determined by two mechanisms: the condensation effect and the capillary effect. Major reductions claimed in literature and patents are found for coating and batter formulations using various types of biopolymers.

Mechanism and reduction of fat uptake in deep-fat fried foods

Integrated approach to deep fat frying: engineering, nutrition, health and consumer aspects

https://moreira.tamu.edu/Deep-fat/Frying_files/sdarticleJagoba.pdf

Vacuum frying of potato chips

Analysis of the oil-absorption process in deep-fat fried potato cylinders (frying temperatures of 155degreesC, 170degreesC, and 185degreesC) allowed to distinguish 3 oil fractions: structural oil (absorbed during frying), penetrated surface oil (suctioned during cooling), and surface oil. Results showed that a small amount of oil penetrates during frying because most of the oil was picked up at the end of the process, suggesting that oil uptake and water removal are not synchronous phenomena. After cooling, oil was located either on the surface of the chip or suctioned into the porous crust microstructure, with an inverse relationship between them for increasing frying times.

Structure Oil‐Absorption Relationships During Deep‐Fat Frying

Modeling heat and mass transfer in immersion frying. I, model development

The fat uptake during deep fat frying of potato strips, French fries, was affected by the pretreatment and the frying time. The highest fat content was observed for blanched, undried potato strips. The surface moisture content seemed to be the limiting factor. The frying time also seemed to influence the fat uptake. During the frying process the drying rate was found to be higher at the beginning of the process. This observation was confirmed by a calculation of the mass transfer coefficients

I. Lamberg

Papers

Fat uptake in a potato drying/frying process