Improvement of soluble solids extraction of Dak Lak coffee by fermentation combined Bio- products from aspergillus carbonarius, pichia guilliermondii and megaterium

Abstract

The soluble solid extraction normally was limited by two major components of coffee those are cellulose and pectin, which were very hard protective layers. The traditional coffee processing is often difficult to break down them. Therefore, there is still a quite large amount of soluble solids left in coffee residue after extraction process. In this research biocoffee-7 used to ferment coffee beans, the bio-product was produced from Asp. Carbonarius, the species had high enzyme activities (cellulase and pectinase). The enzymes hydrolyzed cellulose and pectin layers so that soluble solid content extracted has increased. In addition biocoffee-12 and biocoffee-17 produced from P. guiliermondii and B. megaterium respectively also were used for studying fermentation. The research was only primary study about fermentation in which bio-products were combined to ferment. The coffee fermented process combined biocoffee-7 with biocoffee-12 and the coffee fermented process combined biocoffee-7 and biocoffee-17 have increased soluble solid content from 64.8% to 67.7% in comparison to traditional coffee process. In addition aroma and taste of fermented coffee was also improved. The coffee products have been tested to make sure that they are safe to human by TCVN [AOAC 2007 (991.31) method]. Keywords: Coffee, biocoffee, fermentation, Asp. carbonarius, P. guiliermondii, B. megaterium.