Spray drying of starch submicron particles prepared by high pressure homogenization and mini-emulsion cross-linking Original Research Article

The suspensions containing starch submicron particles prepared through a novel high pressure homogenization and mini-emulsion cross-linking technology were spray dried to obtain cross-linked starch submicron particles. Dryer inlet temperature and feed flow rate were varied to investigate their effect on moisture content, glass transition temperature (Tg), morphology of the starch submicron particles. The residual moisture content of the particles was below 10% (w/w) and particle had collapsed morphology. The Tg of these submicron particles varied between 54 and 57 °C corresponding to moisture contents of 9.78% and 8.31%, respectively and the cross-linking and the high hydrogen bond density in these submicron particles strongly affected the moisture dependence in their Tg. The X-ray diffraction and FT-IR experiments revealed that these starch submicron particles were in amorphous glassy state, fully cross-linked and had very high extent of hydrogen bonding.