Abstract
The hypoallergenic egg will be a beneficial food source for patients with egg hypersensitivity. A novel method for removing ovomucoid (OM), which has high allergenic activity, from egg was developed to allow cooking with hypoallergenic egg. The allergenic activity was evaluated by ELISA competitive analysis using serum from patients allergic to egg. The procedures used in this method were as follows: 1) Egg white was boiled in 0.8% NaCl solution for 15min. 2) Heat-coagulated egg white without OM (-OM) was ground and rinsed with NaCl solution. 3) The egg yolk component was obtained using a syringe through a small opening in a sheet of paper covering the egg yolk to prevent contamination with egg white and egg yolk membrane. The mixture of coagulated egg white and egg yolk, free of OM, was heated at 98°C for 5min. Complete disappearance of OM from the heated egg (-OM) was confirmed by immunoblotting and ELISA inhibition analysis using mouse anti-OM serum. The allergenic activity of OM disappeared almost completely from egg white (-OM) but a small amount remained in the heated egg (-OM). It appeared that some minor nonspecific components binding to IgE were present in the egg yolk, since PBS extracted from the heated egg (-OM) slightly inhibited the binding between milk casein and human anti-casein IgE. The practical use of ovomucoid-depleted egg obtained by the above method may make it possible to produce hypoallergenic egg dishes for people with egg hypersensitivity.
