Abstract
Polyethylene glycol (PEG) was conjugated with milk proteins to determine the changes of the immunoreactive properties of α-lactalbumin (α-la) and β-lactoglobulin (β-lg). The competitive ELISA method was applied to determine the antigenicity of modified protein, using rabbit polyclonal antibodies. The immunoreactivity decreased to 0.90 μg ml-1 α-la (which corresponded with 0.05%) and 0.14 μg ml-1 β-lg (which corresponded with 0.08% of the immunoreactivity observed in raw milk). The determination of allergenicity of modified whey proteins was carried out on a group of 10 allergic patients and it was insignificantly weaker than that of a control sample of milk allergens.