Collagen, especially type I collagen, a major component for connective tissue in meat, determines the background tenderness and affects digestibility of meat. Heating may induce great changes in protein structure and its pepsin-treated digestion. The objective of this study was to investigate how heating affected type I collagen structure and in vitro pepsin-treated digestion. Type I collagen was heated at 60 °C, 70 °C, 80 °C for 0.5 to 2.5 h, and the spectrometric measurements and in vitro pepsin digestion were performed. Increased heating temperature caused the exposure of aromatic residues and an elevation of intensity of synchronous fluorescence spectra, but a reduction in the conformational stability of type I collagen (P < 0.05). Under the in vitro pepsin digestion, the Km value of enzymatic reaction increased as heating temperature rose, but overheating attenuated the affinity of type I collagen to pepsin. Heating at 70 °C for 0.5 h is good for type I collagen to get higher digestion.

胶原蛋白，特别是I型胶原蛋白，是肉中结缔组织的主要成分，它决定了背景的嫩度并影响肉的消化率。加热可能会导致蛋白质结构及其经胃蛋白酶处理的消化发生重大变化。这项研究的目的是研究加热如何影响I型胶原蛋白结构和体外胃蛋白酶处理的消化。将I型胶原蛋白分别在60°C，70°C，80°C加热0.5到2.5 h，然后进行光谱测量和体外胃蛋白酶消化。升高的加热温度导致芳香族残基的暴露和同步荧光光谱强度的提高，但I型胶原的构象稳定性降低（P <0.05）。在体外胃蛋白酶消化下，酶促反应的Km值随着加热温度的升高而增加，但过热会减弱I型胶原蛋白对胃蛋白酶的亲和力。在70°C下加热0.5小时有利于I型胶原蛋白获得更高的消化率。