Rapid production of corn starch gels with high mechanical properties through alcohol soaking

The rapid fabrication of starch gels with excellent mechanical properties still presents a challenge. This study aimed to develop a simple alcohol soaking method to fabricate strong starch gels in a short time. The mechanical properties, crystallization behaviors, and structural characteristics of starch gels were investigated by rheological testing, texture profile analysis, differential scanning calorimetry (DSC), X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and low-field nuclear magnetic resonance (LF-NMR). The mechanical strength of the starch gel increased from 170.21 g to 666.16 g. The gelation time of starch gel decreased from 12 h (traditional retrogradation) to 2 h. DSC indicated that the enthalpy of starch gel increased from 0.88 J/g to 2.90 J/g. XRD analysis showed that the crystallinity of starch gel increased from 3.8% to 8.9% after alcohol soaking. Alcohol dehydrated the starch gels system, so that amylopectins were arranged to form more crystals. This new simple approach, alcohol soaking to form strong starch gels, can expand the applications of starch in food, agriculture, and textiles.