Addition of commercial lactic acid bacteria as starter cultures in anaerobic fermentations of Coffea arabica L., in cherry or raisin stages

The objective of this research was to verify the efficiency of adding commercial lactic acid bacteria (LAB) on anaerobic fermentation of (cherry and raisin) arabica Yellow Catuaí coffees, studying the microbiological succession and its influence in modulating sensorial characteristics on their beverages. The study took place in a rural property in Marília region, Sao Paulo State, Brasil, and was performed according to three different treatments: 1) FNC = spontaneous fermentation of cherry coffees; 2) FCBAL = cherry coffee fermentation using Sacco Lyofast SYAB1 BAL; 3) FPBAL = raisin coffee fermentation using Sacco Lyofast SYAB1 BAL. Fermentations occurred in individual (60 liters) high density polyethylene containers, properly sealed to guarantee anaerobic conditions. After a 48-hour fermentation, all the coffee fruits were washed, beans were depulped and dried on suspended terrace until a 12% humidity was observed. Physical, chemical, microbiological and sensory analysis were performed in samples collected from each fermented batch. Fermentation processes of raisin coffees occurred more slowly than fermentations using cherry coffees and resulted in a lesser consumption of soluble solids and in a slower acidification. Fermentation treatments FNC, FCBAL and FPBAL reached the necessary reduction of Enterobateriaceae and molds. The addition of BAL stimulated the growth of yeasts, which are responsible for the inclusion of the most desired flavor. The fermentations conducted in this experiment resulted in coffee beverages that reached notes of specialty coffees (> 80 points). Even though the raisin coffee achieved a lower note than cherry, the LAB inclusion raised it from 77 (non-fermented raisins) to 80 (FPBAL) points. In cherry fruits, FCBAL got 2 points on final comparation to non-fermented cherries. Thus, the inclusion of LAB presented itself beneficial to anaerobic fermentations of cherry or raisin coffees.