Study on the Cocoa fermentation by using of aspergillus unguis, penicillium citrinum for high soluble solids extraction

Abstract

Fresh cocoa beans have a high amount of polysaccharides and pectin (1.5-3%, 4-7% in pulp and 14-20%, 2% in bean) that are difficult to be hydrolyzed. Traditional fermentation does not consider of this, only focuses on the changes of colour inside the bean to stop fermentation process. However, the polysaccharides and pectin that lead to low quality of fermented beans such as soluble solids extraction because of high amount of unconverted polysaccharides and pectin are not investigated in past. In this research, the enzyme in the bio-products which are high pectinase and cellulase activities hydrolyzed the cellulose and pectin layers so that the soluble solids extraction has increased. In addition Biococoa-25 and Biococoa-23 from Aspergillus unguis and Penicillium citrinum respectively also were used for the cocoa fermentation. This was primary study of combinative fermentation. The cocoa fermented process combined Biococoa-25 and Biococoa-23 have increased soluble solids extraction about 17-20% in comparison to control fermentation. The quality of cocoa beans was also improved by increasing of polyphenol and caffeine contents about 6% and 11-32% compare with control fermentation. The cocoa bean products have been tested to ensure that they are safety.

Keywords: Aspergillus unguis, Penicillium citrinum, cocoa beans, fermentation, TSS extraction.