Quantificação e remoção de íons cobre em cachaças

Abstract

Cachaça is a destilled beverage made from sugar cane, which in Brazil it is produced about 1,6 billions of liters, being about 300 millions considered handmade product and most part of it is produced in copper alembic. Despite the tradition of the beverage, the production chain aims to improve and standardize the quality of cachaça to attend export market demands. One of the production issues is copper (Cu) contamination, coming from the distiller. The Cu presence is assigned to organoleptic characteristics of cachaça, that they are not found in stainless steel distillers. However, copper overload can be toxic due metal affinity to sulfhydryl groups (S-H) from many proteins and enzymes, being associated to several diseases. In this way, this work has as main objective verify the efficience of the following adsorptives: Luffa Cylindrica, polyurethane and barley malt, to remove Cu from handmade cachaça. The main goal is a partial metal removal from the beverage, helding sensorial characteristics and fulfilling the Cu levels required by law. Five samples of handmade cachaça, produced in the missionary region sited northwest of Rio Grande do Sul, were obtained through donation. To determine Cu concentration it was used Flame Atomic Absorption Spectrometry (FAAS). From the five samples of handmade cachaça analyzed by FAAS it was verified that just one did not respect Brazilian law, which establishes a maximum limit of 5 mg.L -1 of Cu in alcoholic distillated. It was also verified that just one presents the allowed regarding exportation that is 2 mg.L -1 of Cu. The absorbent that presented most satisfactory results was Luffa Cylindrica, called bioadsorvent because it is a natural adsorbent. Adsorption tests were performed under agitation time and bioadsorbent mass parameters. Thus, it was observed that time has influence only in smaller masses (0.125 g and 0.250 g). It was found that the amount of 0.750 g of bioadsorbent had higher removal efficiency than the 1.000 g, and it had lower standard deviation. The results obtained have been showed that the study with Luffa Cylindrica allowed partial removal of ion Cu 2+ from handmade cachaça produced in copper alembic. This way of removal can be considered a viable option to obtain a better quality beverage, keeping its sensorial properties and with Cu concentration under the law. A future perspective is to develop a device with Luffa Cylindrica, to be inserted in the alembic improving the quality of local cachaça and making it competitive against others.