Acrylamide in espresso coffee: Influence of species, roast degree and brew length

Espresso coffees were analysed for acrylamide contents by matrix solid-phase dispersion and GC-MS. The influence of coffee species, roast degree, and brew length were ascertained. Mean acrylamide contents of medium roasted espressos (30 mL) were 1.16 +/- 0.25 and 2.31 +/- 0.43 mu g for pure arabica and robusta samples, respectively. Espressos prepared from commercial blends contained an average acrylamide level of 1.26 +/- 0.28 mu g. A 25% decrease was observed when comparing espressos prepared with medium and dark roasted coffee. The extraction efficacy of acrylamide for standard espressos of 30 mL was near 80%, being only affected by brew volume, with long espressos (70 mL) containing practically all acrylamide of the coffee cake (99%), almost double that of short ones (20 mL). When compared with other common coffee beverages, espresso acrylamide concentration (mu g/L) was higher. However, due to the small volume per cup, it may contribute less to acrylamide ingestion. (C) 2009 Elsevier Ltd. All rights reserved.