Effect of ultraviolet irradiation on molecular properties and immunoglobulin production-regulating activity of β-lactoglobulin

To utilize ultraviolet (UV) irradiation as a means to prepare hypo-allergenic food, we investigated the molecular weight profile, secondary structure content, fluorescence spectrum, and immunoglobulin (Ig) production-regulating activity of β-lactoglobulin after UV-irradiation. UV-irradiation caused a change on the molecular size distribution, disruption of the ordered structure, and decrease of emission intensity of β-lactoglobulin. The alteration on Igs production regulating activity of β-lactoglobulin by UV-irradiation was observed in the mouse spleen lymphocytes system. These results suggest that UV-irradiation is effective for alteration of molecular properties and antigenicities of β-lactoglobulin and such treatment should be useful for the preparation of low allergenic foods.