Effects of ohmic heating on the immunoreactivity of β-lactoglobulin - a relationship towards structural aspects.

β-Lactoglobulin (β-LG) encompasses important biological functions, but it is also a major milk allergen, being responsible for the high incidence of cow's milk allergy in childhood. Despite numerous studies addressing the effect of thermal processing on the immunoreactivity of β-LG, little is known about the impact of emergent food processing technologies, such as ohmic heating (OH), on its immunoreactivity. This study describes, for the first time, the effects of thermal and electric effects of OH on the immunoreactivity of β-LG. The influence of high-temperature short time (HTST; 72.5 °C for 15 and 90 °C for 1 s) and low-temperature long time (LTLT; 65 °C for 30 min) pasteurization binomials combined with different electrical variables (electric field intensity and electrical frequency) was evaluated and compared with that of conventional heating. HTST at 90 °C for 1 s extensively affects the protein secondary structure and increases the levels of reactive aggregates, resulting in increased total immunoreactivity (assessed by ELISA and immunoblotting). OH at 4 V cm