Effect of various roasting, extraction and drinking conditions on furan and 5-hydroxymethylfurfural levels in coffee.

Furan and 5-hydroxymethylfurfural (5-HMF) were quantified in 108 coffee models prepared considering the species/origin of the coffee beans, roasting temperature/time, mesh size used to sieve the ground coffee beans, type of extraction water and extraction method. The effect of drinking conditions, such as adding sugar or cream, on furan and 5-HMF levels, was also studied. The range of furan and 5-HMF in coffee samples were 5-362 ppb and 51-1143 ppm, respectively. Furan levels were increased by 198-560% with increasing roasting temperature/time and by 106-399% in cold-brew extracts compared with espresso extracts. Among the mesh sizes used, 500 μm with espresso extraction, and 710 μm with cold-brew extraction led to maximal furan levels. 5-HMF concentration was highest in Robusta coffee and espresso extracts, and decreased by 17-76% with increasing roasting temperature/time. In a drinking condition study, furan level was remained unchanged, even when sugar or cream were added.