Caracterização do glicosídeo cianogênico em variedades de cana-de-açúcar, identificação e quantificação de carbamato de etila em cachaças

Abstract

The beverage obtained through the fermentation process, followed by distillation, which is called Cachaça or Sugarcane Spirits, is produced from sugar cane. The sugarcane (Saccharum spp.) belt is tropical cyanogenic, meaning that it could contain cyanogenic glycosides such as dhurrin and linamarin. These compounds could be associated with the formation of ethyl carbamate (EC), a contaminant that is carcinogenic for humans, classified as a 2A group by the International Agency for Research on Cancer (IARC). The goals of this work were to identify and quantify dhurrin and linamarin in different varieties of sugarcane and in different parts of the plant (points and stems) to correlate the glycosides with the formation of ethyl carbamate during the cachaça production process. Fifteen varieties of sugarcane (points and stems) were collected, and cachaças obtained from those sugarcane varieties were acquired in the local commerce. Twenty-five methanolic extracts were obtained from the sugarcane varieties most widely used for cachaça production. Physical-chemical and chromatographic analyses were performed on the cachaça samples for the identification of the Quality and Identity Standards (PIQ’s) and for the determination of the influence of cyanogenic glycosides on the formation of ethyl carbamate in the beverage. The glycoside linamarin was not detected in any of the samples studied. The glycoside dhurrin was identified in concentrations that varied from non-detected (ND) to 0,0731 mg mL-1 for the sugarcane points and ND to 0,0295 mg mL-1 for the sugarcane stems. Three cachaça samples did not meet the standards for alcoholic content (37.06; 37.38 and 37.51%). Four samples were not in accordance with the legislation for sec-butyl alcohol and ten were not in accordance with the legal limit for acrolein. All the samples were within the legal limit for EC, with values that varied from 7.10 μg L-1 to 21,81 μg L-1. Dhurrin was found in low concentrations in the extracts of the ends and stems of some sugarcane varieties, and its presence can lead to the formation of ethyl carbamate. It is recommended that producers choose the correct sugarcane variety, and they should be cautious in every step in the production chain to avoid the formation of ethyl carbamate.