French fries with less than 100 μg/kg acrylamide.: A collaboration between cooks and analysts

In collaboration with cooking experts, the preparation of French fries in oil and in ovens was optimized, aiming at optimum culinary quality combined with a minimum acrylamide content. French fries with 40-70 mug/kg acrylamide were consistently produced, i.e. with 5-10 times less acrylamide than currently normal. The raw potato should contain little reducing sugars, i.e. be of a suitable cultivar, and storage at temperatures below about 10degreesC must be avoided. After cutting and elimination of the fines, the potato is immersed in standing cold or boiler-warm water for some 15 min in order to extract asparagine and sugars from the surface without washing out the starch. Pre-frying in oil (ca. 140degreesC for 2.5 min) improves crispiness. Frying should occur at an initial oil temperature of about 170degreesC, adding some 100 g potato/l oil. Since acrylamide formation increases exponentially towards the end of the process, the most important factor to keep acrylamide contents low is the determination of the proper end point of the frying process. French fries should be crispy with slight browning of the tips to achieve the typical flavor, but without general browning. Preparation in the oven, starting from frozen prefabricates, requires temperatures of around 190degreesC or 220degreesC, depending on whether or not the air is circulated. The proper determination of the end point is again the most critical step.