Abstract:

【Objective】 The objective is to study the effect of pH on the secondary structure, α-helix of pork myofibrillar protein, and the hardness, water holding capacity (WHC) and microstructure of its heat-induced gel. 【Method】 The α-helix of pork myofibrillar protein under different pH were measured by circular dichroism (CD), and the hardness, WHC and microstructure of the heat-induced gel were determined by texture analyzer, centrifugation method and scanning electron microscope (SEM), respectively. 【Result】 The α-helix of pork myofibrillar protein and WHC of its heat-induced gel increased with pH away from pI, the hardness reached its maximum when pH was 6.0, the gel had a uniform and orderly microstructure in neutral, while it had disorderly and uneven microstructure with polymer in the acidic. 【Conclusion】 The α-helix of myofibrillar protein is positive correlated with the WHC of its heat-induced gelation, and the gel has an orderly microstructure with more α-helix, while rough microstructure with less α-helix.

Key words: pork myofibrillar protein, pH, α-helix, hardness, water holding capacity, microstructure