Many people can taste the difference between coffee from a drip coffee maker or from an espresso machine or from capsules. But taste isn’t the only difference between them — Javier Santos and colleagues, University of Barcelona, Spain, have shown that each of these preparation methods give rise to different levels of furans in coffee. Furans are listed as possible carcinogens in humans.
Santos’ team found that higher concentrations are found in espresso (43‐146 ng/mL) than in coffee made in drip coffee makers (20‐78 ng/mL). Instant coffee displayed the lowest levels of furans (12‐35 ng/ml). The highest levels were reported in coffee made from capsules (117‐244 ng/ml).
The higher levels are due to the hermetically-sealed capsules preventing furan from evaporating during brewing. From this data, they estimated the amount of furan ingested from coffee is 0.03‐0.38 μg/kg of body weight, well below the maximum acceptable level (2 μg/Kg of body weight). To exceed this amount, a person would have to drink at least 20 cups of capsule coffee or 30 espressos per day.
- Occurrence of furan in coffee from Spanish market: contribution of brewing and roasting
M.S. Altaki, F.J. Santos, M.T. Galceran,
Food Chemistry 2011, 126 (4), 1527.
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