Cold Storage Increases Acrylamide Concentrations

Researchers from the University of Ioannina, Ioannina, Greece, found high concentrations of acrylamide in precooked, battered protein foods, and determined that concentrations rise considerably during storage. The study, published in Journal of Food Protection (Feb. 2007; 70:466-470(5)), found that existing acrylamide amounts almost doubled when air was present in the package.

Over a 23-day period, the scientists studied the effect of refrigeration storage on acrylamide levels in 28 commercial, precooked breaded chicken products. Before cold storage, acrylamide concentrations ranged between 0.91 and 0.97 mg kg-1, and were attributed to the combined effect of batter and meat. For all samples, acrylamide concentrations increased during storage, attaining a maximum (1.36 to 1.80 mg kg-1) between day 15 and day 19. The maximum value was observed in samples packaged under air, and the minimum value was observed under a modified-atmosphere mixture of 60% carbon dioxide and 40% nitrogen gas. In this latter group, the maximum acrylamide concentration was reached after 19 days of storage.

According to the study, acrylamide was analyzed by using normal phase high-performance liquid chromatography according to a previously developed methodology that allows for dual identity verification as acrylamide and acrylic acid and determination of concentrations as low as 10 µg liter-1, which corresponds to 20 µg kg-1 of solid sample.