The effects of single-and multiple-stage extraction procedures were studied on the extraction yield of acrylamide for various cereal- and potato-based thermally processed foods. In the multiple-stage procedure, extraction of ground sample was sequentially performed up to four times using 10 mM formic acid or methanol as the extraction solvents. The extraction yield of acrylamide was determined for cacti stage. Single-stage extraction resulted in lower acrylamide concentrations for all food matrices regardless of the type of extraction solvent, solvent-to-sample ratio, prior defatting, extraction temperature and time. The results revealed that a single-stage procedure underestimated the concentration of acrylamide in foods by a factor of up to 50% depending on the type of solvent applied during the extraction. The extractability was an exponential function which can be used to optimize the multiple extraction conditions during the analysts of foods for acrylamide. In general, the aqueous extraction using 10 mM formic acid was found to be more effective than the methanol extraction, and required lesser number of extraction steps for a complete extraction of acrylamide from food. (C) 2008 Elsevier Inc.. All rights reserved.