Level of acrylamide precursors asparagine, fructose, glucose, and sucrose in potatoes sold at retail in Italy and in the United States

The free amino acid asparagine and the reducing sugars glucose and fructose has been reported to serve as precursors for the heat-induced formation of potentially toxic acrylamide in a variety of plant-based food. To contribute to our knowledge about the levels of these precursors, we used ion-exchange chromatography to measure free asparagine and high-performance liquid chromatography (HPLC) to measure free glucose, fructose, and sucrose in 9 potato varieties sold at retail in Italy and in 22 varieties sold in the United States. Asparagine levels (in mmol/kg of fresh wt) ranged from 1.17 for the Agata potatoes to 57.65 Russet potatoes, a 49.3-fold variation from lowest to highest value. The corresponding levels for fructose ranged from 1.73 (Fingerling Ozette) to 33.63 (Red), a 19.4-fold variation from the lowest to the highest value. For glucose, the concentration ranged from 1.11 (Jelli) to 34.73 (Yukon Gold B) potatoes, a 31.3-fold variation from lowest to highest value. The corresponding values for sucrose ranged from 1.16 (Fingerling Ozette) to 40.61 (Marabel) potatoes, a 35-fold variation. The American potato varieties Kennebec, White, and Fingerling Ozette and the Italian potato varieties Agria, Merit, and Marabel had very low levels of both asparagine and reducing sugars. The results may enable consumers, restaurants, and processors to select commercial potatoes with low levels of acrylamide precursors for baking or frying.