Reducing the acrylamide-forming potential of crop plants

Acrylamide is a food processing contaminant formed from free asparagine and reducing sugars during high-temperature cooking and processing. It is a Group 2A carcinogen, and EFSA’s CONTAM Panel has expressed concern for the potential tumour-inducing effects of dietary exposure. Fried, baked, roasted and toasted potato, coffee and cereal products are the major contributors to dietary acrylamide intake. The European Commission has recently introduced strengthened risk management regulations for acrylamide in food, including compulsory mitigation measures and new Benchmark Levels. Steps taken by manufacturers to reduce acrylamide formation in potato chips in Europe resulted in a 53 % decrease from 2002 to 2011. However, since 2011 there has been a levelling off, suggesting that the easy gains have already been made and further large reductions are unlikely. The acrylamide-forming potential of potatoes is influenced by seasonal and geographical factors, making regulatory compliance for potato products more difficult. In cereals, acrylamide formation is determined by free asparagine concentration: this differs substantially between varieties but is also very responsive to environmental factors and crop management. Ensuring good disease control and sulfur sufficiency are particularly important. The relationship between precursor concentration and acrylamide formation is more complex in potato, with the concentration of reducing sugars the more important parameter in most datasets but free asparagine concentration contributing to the variance. Storage is a key issue for potatoes due to the phenomena of cold and senescent sweetening. Investigations into the genetic control of acrylamide formation in wheat have focussed on asparagine metabolism, in particular asparagine synthetase, while biotech potatoes with reduced expression of asparagine synthetase and vacuolar invertase are already on the market in the USA.