Using dynamic high pressure microfluidization, we prepared starch-lipid complexes from lotus seed starch (IS) and six saturated fatty acids (FM) of different carbon chain length and analyzed their semi-crystalline structure and digestibility. Iodine blue value analysis showed the highest complex index (86.3%) was observed between LS and octanoic acid (C8). X-ray diffraction analysis showed crystal structure changed from V6(II) to V-6I type with decreasing FA chain length. Small angle x-ray scattering and differential scanning calorimetry analyses confirmed the presence of a strong V-6I-type mass fractal structure with a Bragg distance of 12.3 nm in LS-C8, which can be considered to be a type-II complex with high melting temperature (T-p = 123.98 degrees C), Scanning electron microscopy results showed the complexes had more spherocrystals with decreasing FA chain length. Compared to other FM, C8 significantly reduced the IS susceptibility to digestive enzymes, increased slowly digestion starch content (26.06%) and decreased digestion rate (3.59 x 10(-2)).