Bioprocess applied to the treatment of residual waters of coffee wet processing for the incorporation of selected yeast strains / Desenvolvimento de bioprocesso aplicado ao tratamento de águas residuais do beneficiamento úmido do café pela incorporaçäo de linhagenm selecionada de leveduras

RESUMO

The aim of the present work was to isolated yeast strains able to degrade the degomming water originated from the wet processing of coffee, characterizing the formed metabolities, The drink prepared from the treated grains by wet processing is considered of better quality when compared with the grains treated by dry process. However, the great polluent potential of the residual water from this processing represents serious concern for the environment. The degumming water essentially presents organic contamination, with Oxygen Biochemical Demand (OBD) and Oxygen Chemical Demand (OCD) rates supeior to 20.000 mg O2/L. Candida tropicalis, C. lypolitica, C. guillermondii, C. parapsilopsis, Kloeckera apiculata e Rhodotorula rubra, isolated from coffee cheeries wew inoculated in flasks containing the degumming water and then submitted to constant agitation (120 rpm) for 48 hours at 28§C. The isolated species revealed capacity to degrade the substrate, however C. parapsilopsia showed reduction percentages of OBD and OCD rates of 50.14 ppor cento e 29.81 por cento, respectivelly, showing the viability of the use of those microorganisme as biological depollutants.