Important factors to consider for acrylamide mitigation in potato crisps using PEF

The EU Regulation (2017/2158) has recently established new “mitigation measures and benchmark levels for the reduction of the presence of acrylamide in foods”. One of the conventional pre-treatment methods for acrylamide reduction is blanching of potato slices, that have the drawback of being time-consuming and of promoting sensorial modifications of the final product. The PEF application has been proposed as an alternative pre-treatment method for the removal of Maillard reaction substrates in food raw materials. The aim of this study was to evaluate the effect of potato crisps manufacturing processes parameters and the application of PEF on the final acrylamide content and quality of the fried product. Raw potatoes (Solanum tuberosum, var. Lady Claire) were manually peeled and sliced and immersed in cold tap water prior to PEF processing. A lab scale PEF unit (Alintel, Italy) delivering rectangular-shape pulses and with a maximum output voltage of 8 kV was used. Different dipping times of PEF treated samples were evaluated. A commercial deep-fat fryer was used for the frying tests (175 °C for 3 mins). The samples were analysed for cell disintegration index (impedance measurement), moisture content, colour, hardness and crispness, oil absorption and acrylamide content. The effect of PEF on raw potato slices was initially studied considering the influence of total number of pulses on the cell disintegration index, as well as the electroporation efficiency considering different sample shapes (tuber/slice) submitted to the same energy treatment. Results showed a significant reduction of acrylamide content in PEF treated samples. Furthermore, the quality of the final fried product was well maintained, resulting in moderate changes, not affecting the overall acceptability. The study showed that PEF application for the mitigation of acrylamide on potato crisps has to be optimised considering the complete manufacturing procedure, particularly the steps affecting the rate of mass transfer.