Formation of crystalline complexes between amylomaize dextrin and ceramide

Complexes between amylomaize dextrin (average DP 311) and ceramide were prepared by using two different blending systems: an aqueous batch system containing ethanol and a two-phase system of isopropyl ether and water. The organic solvents and complex formation temperature (50-90 C) were important in determining the level of complex formation and its crystalline structure. Under X-ray diffraction analysis, the solvents as well as ceramide could form complexes with dextrin as weak V_6I type crystals. However, the crystallinity of complexes was much higher in the presence of ceramide, which would enhance complex formation by forming ternary co-inclusion complexes of dextrin-solvent-ceramide. Compared to the two-phase system, the batch system yielded much higher crystallinity of complexes. With a minor use of ethanol (0.5 mL) in the batch system, aqueous blending of dextrin and ceramide at 50 C for 2 days followed by a storage at 25 C for 1 day produced well-defined V _6I crystal particles as precipitates. The isolated particles had rectangular shapes with a size of 1 μm or less, and contained about half of the ceramide initially added. The ceramide-dextrin complex exhibited enhanced water dispersibility, up to 45% based on the ceramide content in complex.