Study on coffee fermentation by penicillium citrinum and saccharomyces cerevislae

Abstract

In coffee processing today, increasing the dissolved substances from the coffee bean has been studied a lot by many manufacturers who are interested in. However, the total soluble solids extraction is difficult by the two major components in the coffee bean: pectin and cellulose. Pectin and cellulose that respectively makes up 55%, 17% in silk layer. They lead to low quality of coffee beans. It is hard to remove them by physical and chemical methods. For this reason, the biocoffee 23 that is bioproduct from Penicillium citrinum has been used for coffee fermentation. It is high pectinase and cellulase activities hydrolyzed the cellulose and pectin layers so that the soluble solids extraction has increased. However, the fermented coffee from biocoffee 23 has musty flavor that is cause by the fermentation of fungi. In this study, the biocoffee 25 from Saccharomyces cerevisiae is used to ferment coffee that has already fermented with biocoffee 23. Biocoffee 25 is study for removing musty flavor and increasing soluble solid because of the ethanol production ability. By using biocoffee 23, 25, the total soluble solids extraction and caffeine respectively increases 27%, increase 2.3% in the comparison with control fermentation. The coffee bean products have been tested to ensure that they are safety. Keywords: coffee beans, fermentation, Penicillium citrinum,Saccharomyces cerevisiae, total soluble solids.