Ethyl carbamate in cachaça (Brazilian sugarcane spirit): Extended survey confirms simple mitigation approaches in pot still distillation

In 2009, we reported an association between low levels of ethyl carbamate (EC) in pot still cachaças from Paraíba State, Brazil, and distillation in copper pot stills equipped with cooled columns. To strengthen these observations, we extended our study to Pernambuco State and assessed 13 pot still and 20 column still cachaça brands. An EC range from <40 to 532 μg/l was found; 18 brands exceeded the Brazilian limit (150 μg/l), 89% of which were column still types. Mean EC concentration of pot still cachaças was very low (64 μg/l), and was well below the Paraíba study (220 μg/l). An on-site investigation of pot still distilleries associated with <40 μg/l brands showed a connection to differences in the distillation apparatus. Maximising distillation reflux ratios in the ascending parts and minimising exposure to copper in the descending parts (through the use of stainless steel) can reduce EC, and also avoid copper contamination.