Antigenicity of Heated Milk Proteins

The denaturation of α-lactalbumin and β-lactoglobulin in heated milk

“…Salt fractionation of the milk proteins was carried out as described by Aschaffenburg & Drewry (1959) except that, for some of the heated samples, double the normal volumes of nitrates were taken for determination of N by Kjeldahl analysis. Larson & Twarog (1961) and Larson & Hageman (1963) showed that immunodiffusion methods could be used to measure the concentration of native /Mactoglobulin and a-lactalbumin in samples of heated milk, but the results obtained by Luz & Todd (1964), using several immunological methods, suggested that heat denatured protein may still react with antiserum to the native protein. This would invalidate the immunodiffusion methods, whose use in these experiments depends on the ability of the antisera to discriminate between native and heat-denatured protein.…”

Identification of the Atopic Allergen in Cow’s Milk

“…These patients did not have a higher incidence of milk precipitating antibodies than normal, non-allergic persons and atopic individuals not hypersensitive to milk. Of some significance in this respect is also the study of Luz [36]. He found that by heat treat ment (13 min, 245° F) the anaphylactogcnic activity of milk, as detect ed by passive cutaneous anaphylaxis in guinea pigs and Schultz-Dale tests, markedly diminished, whereas the Prausnitz-Kiistncr activity with reagin sera of milk atopic patients hardly showed a difference.…”

“…Actually it cannot be excluded that heating influences the allergenic potency and accordingly the skin reactivity of milk, either diminishing or increasing it. Pasteurization for example, has been shown to lead to modification of the proteins accounting for a loss or decrease of the antigenicity of some of these [29,36,44,46]. On the other hand some evidence has been presented to indicate that heating may give rise to an increase of the anaphylactogenic properties of milk [12,37].…”