Effects of pH, temperature, enzyme-to-substrate ratio and reaction time on the antigenicity of casein hydrolysates prepared by papain

The effects of pH, temperature, enzyme-to-substrate ratio and reaction time on the antigenicity of casein hydrolysates were investigated. Response surface methodology (RSM) was employed to optimise the reaction conditions. Enzymatic hydrolysis with papain could reduce the antigenicity of α-casein and β-casein effectively and the reduction of antigenicity could be controlled by regulation of the reaction conditions. The model for optimal reaction conditions of a lower antigenicity of α-casein and β-casein was established. Under the range of conditions studied, enzyme-to-substrate ratio had the most significant effects on the antigenicity of α-casein and β-casein. The anti-α-casein IgG binding inhibition and anti-β-casein binding inhibition were both significantly negatively related with the degree of hydrolysis (DH).