Color changes and acrylamide formation in fried potato slices

The objective of this work was to study the kinetics of browning during deep-fat frying of blanched and unblanched potato chips by using the dynamic method and to find a relationship between browning development and acrylamide formation. Prior to frying, potato slices were blanched in hot water at 85degreesC for 3.5 min.

Unblanched slices were used as the control. Control and blanched potato slices (Panda variety, diameter: 37 mm, width: 2.2 mm) were fried at 120, 150 and 180degreesC until reaching moisture contents of similar to1.8% (total basis) and their acrylamide content and final color were measured. Color changes were recorded at different sampling times during frying at the three mentioned temperatures using the chromatic redness parameter a(*).

Experimental data of surface temperature, moisture content and color change in potato chips during frying were fit to empirical relationship with correlation coefficients greater than 90%. A first-order rate equation was used to model the kinetics of color change. In all case the Arrhenius activation energy decreases alongside with decreasing chip moisture content.

Blanching reduced acrylamide formation in potato chips in similar to64% (average value) in comparison with control chips at the three oil temperatures tested. For the two pre-treatments studied, average acrylamide content increased -58 times as the frying temperature increased from 120 to 180degreesC.

There was a linear correlation between acrylamide content of potato chips and their color represented by the redness component a(*) in the range of the temperatures studied.