Impact of alkaline electro-activation treatment on physicochemical and functional properties of sweet whey.

The impact of alkaline electro-activation (EA) on the protein solubility, foaming, and emulsifying characteristics of whey was investigated. EA caused protein aggregation and conjugation. At low electric current and holding time, proteins aggregation through disulfide bonds was observed, whereas increasing currents and holding times caused proteins to conjugate with sugars such as lactose, lactulose and galactose. The EA process improved the protein solubility at the pH range of 4.0-7.0. Compared to untreated whey, which produced micron-sized and unstable emulsions at pH 3, whey samples treated under 750 mA and 24-48 h holding time formed nano-sized and stable emulsions at this pH. Furthermore, although both untreated and EA-whey produced stable emulsions at pH 7, those emulsions prepared with EA-whey had smaller particle size and were more stable against droplet flocculation. EA-treated whey tended to generate foams with significantly higher overrun and stability. The present study demonstrated that EA can enhance the functionality of whey.