Modification of IgE binding during heat processing of the cow's milk allergen beta-lactoglobulin.
The effect of heat treatment on the IgE binding ability of beta-lactoglobulin, as pure protein or in whole milk, was studied by inhibition of IgE antibody binding using FEIA-CAP inhibition. A slight but significant decreased IgE binding was seen between unheated and heat-treated beta-lactoglobulin solution at 74 degrees C (IC(50) = 2.03 and 3.59 microg/mL, respectively, p = 0.032). A more pronounced decrease was found at 90 degrees C with an IC(50) of 8.45 microg/mL (p = 0.014). The inhibition of IgE binding of milk after heat treatment at 90 degrees C was also significantly decreased (p = 0.007). However, at all heat treatments, a similar total amount of IgE antibodies could be inhibited at a sufficiently high concentration of beta-lactoglobulin. The inhibiting ability of beta-lactoglobulin was significantly impaired in some fermented acidified milk products such as yogurt as compared to that in nonfermented milk (p < 0.001). There was only a small difference of IgE binding between the native forms of genetic variants A and B.
Ehn
Britt-Marie
BM
SIK-The Swedish Institute for Food and Biotechnology, Göteborg, Sweden. ben@sik.se
Ekstrand
Bo
B
Bengtsson
Ulf
U
Ahlstedt
Staffan
S
D000485:Allergens / Q000276:immunology*; D000818:Animals; D002417:Cattle; D005511:Food Handling; D006358:Hot Temperature; D007073:Immunoglobulin E / Q000378:metabolism*; D007782:Lactoglobulins / Q000276:immunology*; D008892:Milk / Q000737:chemistry*
D000485:Allergens; D007782:Lactoglobulins; D007073:Immunoglobulin E