Changes in solubility, allergenicity, and digestibility of cow's milk proteins in baked milk

Abstract

It has been suggested that patients with cow's milk allergy can ingest baked milk without adverse reactions, although this has not been characterized sufficiently. Here, we investigated the solubility, allergenicity, and digestibility of αs1-casein and β-lactoglobulin when skim milk (SM) was mixed with food ingredients, starch and gluten, and then baked. Samples were analyzed using competitive ELISA, SDSPAGE, and immunoblot. The protein bands of cow's milk proteins (CMP) in baked SM with starch and gluten were shifted up. αs1-Casein and β-lactoglobulin in the PBS extract from the baked SM with gluten decreased compared with that in the baked SM with starch. αs1-Casein and β-lactoglobulin were detected as insoluble fractions. The allergenicity of CMP was significantly decreased by baking and when mixed with gluten. The digestibility of αs1-casein and β-lactoglobulin was unaffected by food ingredients, and insolubilized β-lactoglobulin was not digested and thus remained, especially in baked SM with gluten.