Effect of porcine plasma protein hydrolysates on long-term retrogradation of corn starch

- 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 28 days (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.