Enzymatic production of DFA III from fresh dahlia tubers as raw material

Abstract

Dahlia is an annual ornamental plants and tubers that have not been widely used in Indonesia. Dahlia tubers contain nearly 70 per cent of the starch in the form of inulin. Inulin addition can be used as a food ingredient can also be used as a raw material for making DFA III (ie functional oligosaccharides), using inulin fructotransferase (IFTase) Nonomuraea sp. In this study conducted production of DFA III through enzymatic reactions and yeast fermentation, using inulin from fresh dahlia tubers and fresh dahlia tuber extract. Dahlia tubers which is one source of inulin, do blanching before extracted. Most dahlia tuber extract used directly for enzymatic reactions in the production of DFA III and some extracts are processed to produce inulin by precipitation using ethanol and then inulin is used for the enzymatic reaction. Syrup DFA III was measured volume and viscosity, and then do decolorization and then crystallization. The analysis was done of Thin Layer Chromatography (to see DFA III formed) and HPLC to see the purity of the product. The results showed that the average of inulin from precipitation with ethanol in the two batch of 113,5 g with an average water content of 7.41%, average whiteness degree 62.29% and an average yield 7.345% (w/w, wb dahlia tuber). From the average of DFA III liquid of 480 mL with density of 14.15%, the result of the average of DFA III crystal from enzyme reaction in the two reactor using inulin dahlia tubers as a substrate, was obtained of 55.4 g with an average whiteness degree of 93.8%, and the average of yield 3.56% w/w (wb dahlia tuber) or 48.89% w/w (db inulin). And then from the average of 475 mL with density of 16.85% was obtained an average DFA III crystals of 29 g from the enzyme reaction in the two reactor using fresh dahlia tuber extract as a substrate, with an average whiteness degree o 80.75% and the average of the yield of 1.86% w/w (wb dahlia tuber).