Influence of frying conditions on acrylamide content and other quality characteristics of French fries

The objective of this work was to investigate the effect of processing frying conditions, simulating possible home and catering practices, in order to optimize the process to obtain a good final product limiting the acrylamide (AA) formation. Experiments were performed using commercially frozen pre-fried potato strips, a fixed initial frying temperature of 180 °C, two different fryers for domestic (A) and catering (B) use, and two potato-to-oil ratios (1/4 and 1/8 w/v). Several batches were fried at different fixed times, and for each batch the temperature of oil and stick surface were acquired by thermocouples. Analysis of AA and other quality characteristics (water and oil content, color, texture) of French fries were carried out. In all adopted frying conditions the increase of oil and potato surface temperature was faster in fryer A than in fryer B due to its peculiar manufacturing characteristics and employment mode. As a consequence, higher AA levels and a more cooked product were obtained using fryer A. With the immersion of a lower potato quantity (1/8 w/v), higher oil temperatures and AA levels and a more cooked product were obtained in shorter time in both fryers. Considering quality parameter results, the best quality characteristics were obtained in potatoes from fryer B between 10 and 13 min of frying with a product-to-oil ratio of 1/4 (around 250 ± 20 μg kg−1 of AA), and after about 7 min of processing with a product-to-oil ratio of 1/8 (around 260 ± 50 μg kg−1 of AA).