Acrylamide formation and colour development in low-fat baked potato products as influenced by baking conditions and oil type

The objective of this study was to investigate the effect of oil type and oxidation status on acrylamide (AA) formation and colour development in potato products under domestic baking conditions. Sunflower, soybean and olive oil were used; the first one was thermally oxidized to obtain different oxidation status. A potato dough containing 10 % oil, potato powder, flour and water was shaped into thin discs and baked at 180 °C for different heating times. AA concentration, moisture content and surface colour were determined. Results obtained showed that neither the nature of lipids present, in terms of content of unsaturated fatty acids, nor the degree of fat oxidation influenced AA formation in low-fat baked potato products. Browning ratio higher than 45 % and moisture content lower than 17 % resulted in dark brown, almost burnt, products. Moreover, in those cases, no correlation could be found between those variables and AA content, since formation and degradation simultaneously occur. When the browning ratio ranged between 0 and 45 %, a good linear correlation with AA formation was observed, suggesting that the browning ratio may be considered as a reliable indicator of AA concentration. Finally, AA less than 1000 μg/kg, which is an indicative value that has been recently set for potato crisps by the European Commission, corresponds to a browning ratio of less than 8 % and moisture content more than 23.5 %.