The Effect ofα-Lactalbumin and β-Lactoglobulin on the Texturization of Rennet Casein

The effect of the addition of α-lactalbumin and β-lactoglobulin fractionated from whey protein isolate (WPI) on the texturization of rennet casein was investigated. Each whey protein component was added to rennet casein at a level of 5% on a dry basis. Surface hydrophobicity of each textured casein product was determined by using 1-anilino-8-naphthalene-sulfonate (ANS) and hydrophobic gel chromatography. An addition of β-lactoglobulin was found to be effective on decreasing the hydrophobicity of the resultant textured product, whereas α-lactalbumin was not. A decrease of the hydrophobicity, which was shown when β-lactoglobulin was added, was possibly associated with the formation of β-lactoglobulin-casein complex during cooking. The fibrousness of the product blended with β-lactoglobulin was superior to that containing α-lactalbumin. It was indicated that β-lactoglobulin contained in WPI played a major role in improving the fibrousness of the resultant textured product.