Food borne toxicants in coffee: Acrylamide and furan derivative content in Arabica and Robusta coffees with different roasting profiles and varying degrees of roast

Abstract

To evaluate mitigation options for both acrylamide and furan and methylfurans a Vietnam Robusta grade 2 and a Brazil Arabica (unwashed) coffee were roasted by tangential, drum and hot air roasting. Three different roasting profiles were followed and three samples (light, medium and dark roast) were obtained per profile. Decaffeinated and steam treated batches of the two coffees were roasted. Special roasts, such as double roast (on 2 days with cooling down in between) or roasting with a sudden temperature change were studied. The contaminants were analyzed by GC-MS – in case of the furans headspace GC-MS – using deuterated standards. The acrylamide contents were highest in light roasts, and decreased after that with longer roasting time. This was true for both the Robusta and Arabica samples. The content of furan and 2-, 3-and 2, 5-methylfurans were low in light roasts and had a maximum in dark roasts. It is possible to minimize the content of either acrylamide and furans, however, a mitigation of both could not be established by changing the roasting parameters or using pretreatments. Among the furans determined, 2-methylfuran was most abundant (average around 70%), followed by furan (average around 20%). The special roasts showed no options to minimize both contaminants as did the pretreatments. In Vietnam Robusta, furan related compounds were measured. 5-hydroxymethylfurfural and 5-hydroxymethylfurfuryl-2-carboxylic acid decreased with the degree of roast and time, while furfuryl alcohol and 2-furoic acid content increased.