A Direct Process for the Production of High Fructose Syrups from Dates Extracts

Abstract

A process comprising of extraction, fermentation, separation and decolorization for the production of high fructose syrups and/or ethanol from dates' extract was developed. In this paper, selective fermentation of the glucose component in dates' extract by Saccharomyces cerevisiae was employed to tailor the composition of the final product (fructose- or ethanol-rich). Over 90% of dates’ sugar was extracted by water. The fermentation experiments were conducted at 30 °C and 120 rpm. The commonly marketed 55% fructose syrup was obtained at two operating conditions, i.e., low (<50%) and high (>92%) sugar conversions. Maximum fructose concentrations (77.2-78.2%) were obtained at moderately high sugar conversions (74-82%). Decolorization by activated carbon for the fructose-rich syrup resulted in 87% of color removal. Preliminary economic analysis revealed the viability of this process.