Abstract
The effects of the concentration and heating temperature of collagen-peptide from pig skin (CP) on the mechanical and thermal properties of agar gel (AG) were studied by measuring the rupture properties, dynamic viscoelasticity, and differential scanning calorimetry (DSC). The frequency dependence of G′ and G″ of a 50 w/w% CP solution showed that it behaved as a liquid even when cooled to 10°C. The rupture strain, stress and storage modulus of the AG-CP gel decreased with increasing CP concentration >20 w/w%. AG (5 w/w%) showed an endothermic peak at 78.8°C by heating DSC, and an exothermic peak at 32.5°C by cooling DSC. A solution of CP (30 w/w%) showed an endothermic peak at 20.2°C and an exothermic peak at 10.0°C. Mixtures of AG (5 w/w%) and CP (10~40 w/w%) showed two endothermic peaks, while AG (5 w/w%) and CP (50 w/w%) showed one endothermic peak. It is suggested that CP inhibited the gelation of AG. The molecular weight of CP was unchanged by heating at 60°C and 90°C, although the storage modulus and rupture strain of the AG-CP gel at 90°C were a little larger than the values 60°C.
