Observations on the rheological and functional properties of model cheeses made using milk protein concentrate solutions with different ratios of α_s1-: β-casein

The effects of varying the ratio of α_s1-:β-casein of milk on the Theological and functional properties of cheese were investigated. Directly acidified, fat-free cheeses were manufactured from milk protein concentrate (MPC) solutions with identical concentrations of casein (2.5%), but different α_s1-:β-casein ratios. One MPC solution (LBCN) had an α_s1-:β-casein ratio of 1.00:1.08, while the other (LBCN) had an α_s1-:β-casein ratio of 1.00:1.00, i.e., partially depleted of β-casein by cold microfiltration. Cheese made from the LBCN solution had lower values for firmness, storage modulus at 70°C (index of elastic-like character) and higher values for the maximum in loss tangent (index of melt/flow) compared with cheese made with HBCN solution. The degree of flow of the cheeses, as measured by melt profile analysis, increased significantly with a reduction in the proportion of β-casein. In conclusion, partial depletion of β-casein strongly influenced the rheological and functional properties, especially meltability, of cheese.