•Addition of PPPH led to inadequate gelatinization of corn starch.•PPPH facilitated water mobility in the crystalline structure of starch.•Addition of PPPH facilitated the reorganization of crystalline regions.•PPPH interfered with the nucleation of amylopectin and inhibited CS retrogradation. The potential effect of porcine plasma protein hydrolysates (PPPH) on the long-term retrogradation of corn starch (CS) was investigated. The differential scanning calorimetry results showed that PPPH significantly reduced the retrogradation enthalpies (ΔHr) of CS (P<0.05), obviously decreased the crystallization rate constant (k), and enhanced the Avrami exponent (n) (P<0.05). Low-field nuclear magnetic resonance analysis demonstrated that the spin–spin relaxation time (T2) remarkably increased with increasing PPPH concentration during storage at 4°C for 28days (P<0.05). The X-ray diffraction results revealed that the relative crystallinity of retrograded CS decreased from 13.04% to 8.73% with the addition of PPPH. Fourier transform infrared spectroscopy analysis demonstrated that the addition of PPPH led to a decrease in hydrogen bonds within starch. The results demonstrated that the addition of PPPH apparently played a crucial role in retarding the long-term retrogradation of CS.