Impact of heat treatments and some technological processing on immunoglobulins of Egyptian buffalo's milk

Abstract

The effects of heat treatments, ultrafiltration and manufacture of soft cheese on the gross composition and immunoglobulins (Igs) of Egyptian buffalos were investigated. Four Igs (IgG1, IgG2, IgM and IgA) were identified and determined by single radial immunodiffusion (SRID). High concentrations of Igs were found in colostrum which decreased rapidly within the first 72 h postpartum parallel to the transition from colostrum to normal milk. IgG (IgG1, IgG2) and IgM were not completely denatured by pasteurization temperature up to 80 °C/15 s, while IgA was completely denatured under these conditions. Ultrafiltration of milk resulted in retentate of high values for total IgG (IgG1, IgG2), but low in IgM and IgA content and permeate was free of Igs. Domiati cheese made from UF-milk retentate contained similar levels of Igs to the used retentate.