Cutting back on chippy chemical

The global fight against possible carcinogen in foods intensifies. 

The furore over acrylamide, a possible carcinogen found in many baked and fried foods, may have died down but researchers are still hard at work trying to find ways to reduce concentrations of the chemical. Researchers from McCain Foods in Canada, best known for its potato chips, are working with a team from Health Canada in Ontario to lower acrylamide levels and in a recent paper suggest that one way to do this might be to use low-sugar potato varieties. Meanwhile, German researchers advise eating protein with fried foods to help soak up the acrylamide.

The acrylamide alarm was first raised in 2002 and it is now widely accepted that the chemical probably forms when asparagine, an amino acid, takes part in a Maillard reaction with a sugar (see Chem. Br., November 2002, p15).

The Canadian researchers made chips using 66 potato samples with different sugar and free amino acid contents. They fried the chips and measured acrylamide levels using liquid chromatography-mass spectrometry (LC-MS/MS). All of the chips contained acrylamide and the team found sugar levels to correlate well with concentrations of acrylamide. However, asparagine levels were not strong predictors of potential levels of acrylamide in fried products.

The researchers suggest that selecting low sugar potatoes can substantially reduce acrylamide content. Whether the low-sugar chips would be marketable is another question. Rachel Burch, from Leatherhead Foods, UK, told Chemistry World that the low-sugar potato chips’ commercial viability would depend greatly on the colour of the chips, because acrylamide levels are closely linked to browning. In the Canadian study, all of the chips were cooked for the same length of time, and Burch thinks that ’it would be useful to know what level of browning was acheived, and whether this had any correlation with the levels of reducing sugar and acrylamide formed’. A spokesperson from McCain said that it was ’premature to comment’ on the work.

Meanwhile, in experiments using a human intestine model, German researchers have discovered that acrylamide monomers are highly bioavailable and cross a cell monolayer via passive diffusion. They also found that acrylamide binds to dietary proteins such as chicken egg albumen, and suggest that a protein-rich diet may help to reduce acrylamide uptake.

Emma Davies