Detection of Remaining Antigenic Activeity of Major Antigen in the Process Foods

鸡蛋和牛奶是儿童的主要过敏性食物，被用于各种烹饪和加工食品中。但关于它们在添加鸡蛋或牛奶的食品中的抗原性的报道很少。在添加蛋清或脱脂牛奶的意大利面和面包制作过程中，主要的蛋清和牛奶蛋白的抗原性被检测出来。用兔抗卵粘蛋白(OM)血清竞争抑制法检测了面包制作过程中OM的抗原性。OM抗原性在烘焙面包中完全消失，而在捏合和发酵面团样品中未见。用兔抗-β-乳球蛋白(β-LG)竞争酶联免疫吸附试验(EL ISA)分析了脱脂牛奶面包样品中残留的β-乳球蛋白(β-LG)抗原性在面包制作的几个阶段中的抗原性，发现烘焙面包中的β-LG抗原性也消失了，但面团样品中没有。面包样品中的OM或β-LG可被含有十二烷基硫酸钠的溶液增溶，而不能被单独含有十二烷基硫酸钠的溶液增溶。这表明，面粉烘焙引起OM或β-LG的不可逆变性，并发生二硫键交换反应，导致其抗原性丧失，其抗原性是基于OM或β-LG分子中的九个或两个S-S键。蛋清意大利面的制备工艺为：捏合10~50min，烘干1h，煮沸15min。OM在搅拌30min或更长时间的煮过的意大利面和在煮过的盐溶液中都不消失，而在与搅拌20min或更短的意大利面一起煮的溶液中则不消失。

Chicken egg and milk which are major allergenic foods for children, are used in various cooked and processed foods. But there have been few reports on their antigenic activities in the foods supplemented with either egg or milk.The antigenic activities of major egg white and milk proteins were examined in the process of pasta-and bread-making with supplementing egg white or skim milk. Particularly, ovomucoid (OM) antigenicity was examined in the process of breadmaking using competitive inhibition ELISA with rabbit anti-OM serum. OM antigenicity was completely disappeared in the baked bread but not in the kneaded and fermentated dough samples. Antigenic activity of beta-lactoglobulin (beta-LG) antigenicity remaining in bread samples containing skim milk was analyzed during several stages of bread making by the competitive ELISA using rabbit ant-beta-LG.beta-LG antigenicity was also disappered in the baked bread but not in the dough samples. OM or beta-LG in the baked bread samples was solubilized with SDS/2-ME-containing solution but not with the solution containig SDS alone, suggesting that baking with wheat flour induced the irreversible denaturation of OM or beta-LG with a disulfide exchange reaction leading to the loss of their antigenic activity which is based on the nine or two S-S bonds in a OM or beta-LG molecule. The pasta containing egg white was prepared with the process of kneading for 10 to 50 min, benching for 1 hr and boiling for 15 min. OM was disappered both in the boiled pasta which was kneaded 30 min or more and in the boiled salt solution but not in the solution boiled with the pasta which was kneaded 20 min or less.