Study of the dextrose equivalent of maltodextrins in electrospinning using an ethanol/water mixture as the electrospinning solvent

Maltodextrin (MD) is a natural polymer ideal for electrospinning due to its non-toxicity, water solubility, and low viscosity. In this investigation, MD solutions, each containing a different dextrose equivalent (DE) value of 18, 10, and 4, were studied in an ethanol/water solvent system for the manufacture of fibers, and their rheological properties and electrospinnability were evaluated. The viscosity data from the solutions indicated that the entanglement concentration (Ce) was higher in the MD solution with the highest DE value, with a value of 40.02% (w/v). As the concentration of MD in the electrospinning solutions increased, the transition of the beads to a beads-fibers mixture and finally to fibers was observed, this behavior being more notable in MD18. To obtain well-formed MD fibers, the optimum concentrations of MD18 and MD10 were found to be 1.30 and 1.22 times the Ce, respectively. Smooth, continuous fibers without beads and diameters of 627.52 +/- 146.12 nm and 748.20 +/- 256.48 nm, respectively, were produced, while in the MD solution with DE 4, a cluster of short fibers with a diameter of 620.23 +/- 167.09 nm was observed. The electrical conductivity significantly influenced the diameter of the fibers, and it was apparent that as the concentration of MD increased, the solution's electrical conductivity decreased. Electrospun MD fibers were characterized using scanning electron microscopy, Fourier transform infrared spectroscopy (FTIR), and differential scanning calorimetry. This study provides a means of producing MD fibers for use in food applications as vehicles for bioactive compounds.