Supercritical Technology-Based Date Sugar Powder Production: Process Modeling and Simulation

Abstract

Date palm fruits (Phoenix dactylifera) contain high levels of fructose and glucose sugars. These natural sugar forms are healthy, nutritional and easily assimilate into human metabolism. The successful production of soluble date sugar powder from nutritious date fruits would result in a new food product that could replace the commercial refined sugar. In this work, a novel process technology based on the supercritical extraction of sugar components from date pulp was modeled and simulated using Aspen Plus software. The process model consisted of three main steps that were individually simulated for their optimal working conditions as follows: (a) freeze-drying of the date pulp at −42 °C and 0.0001 bar; (b) supercritical extraction of the sugar components using a 6.77 wt.% water mixed CO2 solvent system at a pressure of 308 bar, temperature of 65 °C, and CO2 flow rate of 31,000 kg/h; and (c) spray-drying of the extract using 40 wt.% Gum Arabic as the carrier agent and air as drying medium at 150 °C. The overall production yield of the process showed an extraction efficiency of 99.1% for the recovery of total reducing sugars from the date fruit. The solubility of the as-produced date sugar powder was improved by the process selectivity, elimination of insoluble fiber contents, and the addition of Gum Arabic. The solubility of the final date sugar product was estimated as 0.89 g/g water.