THE EFFECT OF ALPHA-LACTALBUMIN AND BETA-LACTOGLOBULIN ON THE TEXTURIZATION OF RENNET CASEIN

The effect of the addition of alpha-lactalbumin and beta-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 hydrophobici ty of each textured casein product was determined by using 1-anilino-8 -naphthalene-sulfonate (ANS) and hydrophobic gel chromatography. An ad dition of beta-lactoglobulin was found to be effective on decreasing t he hydrophobicity of the resultant textured product, whereas alpha-lac talbumin was not. A decrease of the hydrophobicity, which was shown wh en beta-lactoglobulin was added, was possibly associated with the form ation of beta-lactoglobulin-casein complex during cooking. The fibrous ness of the product blended with beta-lactoglobulin was superior to th at containing alpha-lactalbumin. It was indicated that beta-lactoglobu lin contained in WPI played a major role in improving the fibrousness of the resultant textured product.