Abstract:

Interactive effects among pH, concentrations of NaCl and MgC12 and mixed phosphates (MP) amount on extraction yield and water holding capacity (WHC) and bloom strength of heat-induced gel of salt-soluble protein from pork hind leg muscle were studied using response surface methodology based on a five-level central composite design involving 31 experiments, data from which were fitted to establish multi-regression quadratic models for predicting the above three indexes. The optimum levels of pH, concentrations of NaCl and MgC12 and MP amount were determined to be 6.7, 0.7 mol/L, 0.006 mol/L and 2.5 g/kg, respectively, which yielded an extraction yield of 9.41%, a WHC of 86.13% and a bloom strength of 86.50 g. The interaction between MgCl2 concentration and MP amount could significantly enhance extraction yield of salt-soluble protein from pork hind leg muscle, and the interactions among various factors had significant effects on WHC and bloom strength of heat-induced gel of pork salt-soluble protein.

Key words: pork hind leg muscle, heat-induced gel, response surface methodology, water holding capacity (WHC), bloom strength (BS)